4.9.188-stable review

This is the start of the stable review cycle for the 4.9.188 release. There are 42 patches in this series, all will be posted as a response to this one. If anyone has any issues with these being applied, please let me know.

Responses should be made by Wed 07 Aug 2019 12:47:58 PM UTC. Anything received after that time might be too late.

The whole patch series can be found in one patch at:

	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.188-rc1.gz

or in the git tree and branch at:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <[email protected]>

    Linux 4.9.188-rc1

Vlastimil Babka <[email protected]>
x86, mm, gup: prevent get_page() race with munmap in paravirt guest

Josh Poimboeuf <[email protected]>
objtool: Support GCC 9 cold subfunction naming scheme

Miguel Ojeda <[email protected]>
include/linux/module.h: copy __init/__exit attrs to init/cleanup_module

Miguel Ojeda <[email protected]>
Backport minimal compiler_attributes.h to support GCC 9

Jean Delvare <[email protected]>
eeprom: at24: make spd world-readable again

Andrea Arcangeli <[email protected]>
coredump: fix race condition between collapse_huge_page() and core dumping

Ajay Kaher <[email protected]>
infiniband: fix race condition between infiniband mlx4, mlx5 driver and core dumping

Andrea Arcangeli <[email protected]>
coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping

Yishai Hadas <[email protected]>
IB/mlx5: Fix RSS Toeplitz setup to be aligned with the HW specification

Juergen Gross <[email protected]>
xen/swiotlb: fix condition for calling xen_destroy_contiguous_region()

Will Deacon <[email protected]>
drivers/perf: arm_pmu: Fix failure path in PM notifier

Stefan Haberland <[email protected]>
s390/dasd: fix endless loop after read unit address configuration

Ondrej Mosnacek <[email protected]>
selinux: fix memory leak in policydb_init()

Michael Wu <[email protected]>
gpiolib: fix incorrect IRQ requesting of an active-low lineevent

Douglas Anderson <[email protected]>
mmc: dw_mmc: Fix occasional hang after tuning on eMMC

Filipe Manana <[email protected]>
Btrfs: fix incremental send failure after deduplication

Masahiro Yamada <[email protected]>
kbuild: initialize CLANG_FLAGS correctly in the top Makefile

Zhenzhong Duan <[email protected]>
x86, boot: Remove multiple copy of static function sanitize_boot_params()

Josh Poimboeuf <[email protected]>
x86/kvm: Don't call kvm_spurious_fault() from .fixup

Kees Cook <[email protected]>
ipc/mqueue.c: only perform resource calculation if user valid

Dan Carpenter <[email protected]>
drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings

Mikko Rapeli <[email protected]>
uapi linux/coda_psdev.h: move upc_req definition from uapi to kernel side headers

Sam Protsenko <[email protected]>
coda: fix build using bare-metal toolchain

Zhouyang Jia <[email protected]>
coda: add error handling for fget

Doug Berger <[email protected]>
mm/cma.c: fail if fixed declaration can't be honored

Arnd Bergmann <[email protected]>
x86: math-emu: Hide clang warnings for 16-bit overflow

Qian Cai <[email protected]>
x86/apic: Silence -Wtype-limits compiler warnings

Benjamin Poirier <[email protected]>
be2net: Signal that the device cannot transmit during reconfiguration

Arnd Bergmann <[email protected]>
ACPI: fix false-positive -Wuninitialized warning

Benjamin Block <[email protected]>
scsi: zfcp: fix GCC compiler warning emitted with -Wmaybe-uninitialized

Jeff Layton <[email protected]>
ceph: return -ERANGE if virtual xattr value didn't fit in buffer

Andrea Parri <[email protected]>
ceph: fix improper use of smp_mb__before_atomic()

David Sterba <[email protected]>
btrfs: fix minimum number of chunk errors for DUP

Russell King <[email protected]>
fs/adfs: super: fix use-after-free bug

Geert Uytterhoeven <[email protected]>
dmaengine: rcar-dmac: Reject zero-length slave DMA requests

Petr Cvek <[email protected]>
MIPS: lantiq: Fix bitfield masking

Prarit Bhargava <[email protected]>
kernel/module.c: Only return -EEXIST for modules that have finished loading

Cheng Jian <[email protected]>
ftrace: Enable trampoline when rec count returns back to one

Douglas Anderson <[email protected]>
ARM: dts: rockchip: Mark that the rk3288 timer might stop in suspend

Douglas Anderson <[email protected]>
ARM: dts: rockchip: Make rk3288-veyron-mickey's emmc work again

Douglas Anderson <[email protected]>
ARM: dts: rockchip: Make rk3288-veyron-minnie run at hs200

Russell King <[email protected]>
ARM: riscpc: fix DMA

-------------

Diffstat:

 Makefile                                    |  7 +--
 arch/arm/boot/dts/rk3288-veyron-mickey.dts  |  4 --
 arch/arm/boot/dts/rk3288-veyron-minnie.dts  |  4 --
 arch/arm/boot/dts/rk3288.dtsi               |  1 +
 arch/arm/mach-rpc/dma.c                     |  5 +-
 arch/mips/lantiq/irq.c                      |  5 +-
 arch/x86/boot/compressed/misc.c             |  1 +
 arch/x86/boot/compressed/misc.h             |  1 -
 arch/x86/include/asm/apic.h                 |  2 +-
 arch/x86/include/asm/kvm_host.h             | 34 +++++++------
 arch/x86/kernel/apic/apic.c                 |  2 +-
 arch/x86/math-emu/fpu_emu.h                 |  2 +-
 arch/x86/math-emu/reg_constant.c            |  2 +-
 arch/x86/mm/gup.c                           | 32 +++++++++++-
 drivers/android/binder.c                    |  6 +++
 drivers/dma/sh/rcar-dmac.c                  |  2 +-
 drivers/gpio/gpiolib.c                      |  6 ++-
 drivers/infiniband/hw/mlx4/main.c           |  4 +-
 drivers/infiniband/hw/mlx5/main.c           |  3 ++
 drivers/infiniband/hw/mlx5/qp.c             |  1 -
 drivers/misc/eeprom/at24.c                  |  2 +-
 drivers/mmc/host/dw_mmc.c                   |  3 +-
 drivers/net/ethernet/emulex/benet/be_main.c |  6 ++-
 drivers/perf/arm_pmu.c                      |  2 +-
 drivers/rapidio/devices/rio_mport_cdev.c    |  2 +
 drivers/s390/block/dasd_alias.c             | 22 ++++++---
 drivers/s390/scsi/zfcp_erp.c                |  7 +++
 drivers/xen/swiotlb-xen.c                   |  4 +-
 fs/adfs/super.c                             |  5 +-
 fs/btrfs/send.c                             | 77 ++++++-----------------------
 fs/btrfs/volumes.c                          |  3 +-
 fs/ceph/super.h                             |  7 ++-
 fs/ceph/xattr.c                             | 14 +++---
 fs/coda/psdev.c                             |  5 +-
 fs/proc/task_mmu.c                          | 18 +++++++
 fs/userfaultfd.c                            |  9 ++++
 include/linux/acpi.h                        |  5 +-
 include/linux/coda.h                        |  3 +-
 include/linux/coda_psdev.h                  | 11 +++++
 include/linux/compiler.h                    | 16 ++++++
 include/linux/mm.h                          | 24 +++++++++
 include/linux/module.h                      |  4 +-
 include/uapi/linux/coda_psdev.h             | 13 -----
 ipc/mqueue.c                                | 19 +++----
 kernel/module.c                             |  6 +--
 kernel/trace/ftrace.c                       | 28 ++++++-----
 mm/cma.c                                    | 13 +++++
 mm/khugepaged.c                             |  3 ++
 mm/mmap.c                                   |  6 ++-
 security/selinux/ss/policydb.c              |  6 ++-
 tools/objtool/elf.c                         |  2 +-
 51 files changed, 294 insertions(+), 175 deletions(-)

[ Upstream commit ffd9a1ba9fdb7f2bd1d1ad9b9243d34e96756ba2 ]

DMA got broken a while back in two different ways:
1) a change in the behaviour of disable_irq() to wait for the interrupt to finish executing causes us to deadlock at the end of DMA.
2) a change to avoid modifying the scatterlist left the first transfer uninitialised.

DMA is only used with expansion cards, so has gone unnoticed.

---
 arch/arm/mach-rpc/dma.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

index 6d3517dc4772a..82aac38fa2cff 100644
@@ -131,7 +131,7 @@ static irqreturn_t iomd_dma_handle(int irq, void *dev_id)
 	} while (1);
 
 	idma->state = ~DMA_ST_AB;
-	disable_irq(irq);
+	disable_irq_nosync(irq);
 
 	return IRQ_HANDLED;
 }

@@ -174,6 +174,9 @@ static void iomd_enable_dma(unsigned int chan, dma_t *dma)
 				DMA_FROM_DEVICE : DMA_TO_DEVICE);
 		}
 
+		idma->dma_addr = idma->dma.sg->dma_address;
+		idma->dma_len = idma->dma.sg->length;
+
 		iomd_writeb(DMA_CR_C, dma_base + CR);
 		idma->state = DMA_ST_AB;
 	}

2.20.1

[ Upstream commit 1c0479023412ab7834f2e98b796eb0d8c627cd62 ]

As some point hs200 was failing on rk3288-veyron-minnie. See commit 984926781122 ("ARM: dts: rockchip: temporarily remove emmc hs200 speed from rk3288 minnie"). Although I didn't track down exactly when it started working, it seems to work OK now, so let's turn it back on.

To test this, I booted from SD card and then used this script to stress the enumeration process after fixing a memory leak [1]:
cd /sys/bus/platform/drivers/dwmmc_rockchip
for i in $(seq 1 3000); do
echo "========================" $i
echo ff0f0000.dwmmc > unbind
sleep .5
echo ff0f0000.dwmmc > bind
while true; do
if [ -e /dev/mmcblk2 ]; then
break;
fi
sleep .1
done
done

It worked fine.

[1] https://lkml.kernel.org/r/[email protected]

---
 arch/arm/boot/dts/rk3288-veyron-minnie.dts | 4 ----
 1 file changed, 4 deletions(-)

index f72d616d1bf8d..9647d9b6b299c 100644
@@ -125,10 +125,6 @@
 	power-supply = <&backlight_regulator>;
 };
 
-&emmc {
-	/delete-property/mmc-hs200-1_8v;
-};
-
 &gpio_keys {
 	pinctrl-0 = <&pwr_key_l &ap_lid_int_l &volum_down_l &volum_up_l>;
 

2.20.1

[ Upstream commit 99fa066710f75f18f4d9a5bc5f6a711968a581d5 ]

When I try to boot rk3288-veyron-mickey I totally fail to make the eMMC work. Specifically my logs (on Chrome OS 4.19):

mmc_host mmc1: card is non-removable.
mmc_host mmc1: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0) mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot req 52000000Hz, actual 50000000HZ div = 0)
mmc1: switch to bus width 8 failed
mmc1: switch to bus width 4 failed
mmc1: new high speed MMC card at address 0001
mmcblk1: mmc1:0001 HAG2e 14.7 GiB
mmcblk1boot0: mmc1:0001 HAG2e partition 1 4.00 MiB
mmcblk1boot1: mmc1:0001 HAG2e partition 2 4.00 MiB
mmcblk1rpmb: mmc1:0001 HAG2e partition 3 4.00 MiB, chardev (243:0)
mmc_host mmc1: Bus speed (slot 0) = 400000Hz (slot req 400000Hz, actual 400000HZ div = 0) mmc_host mmc1: Bus speed (slot 0) = 50000000Hz (slot req 52000000Hz, actual 50000000HZ div = 0)
mmc1: switch to bus width 8 failed
mmc1: switch to bus width 4 failed
mmc1: tried to HW reset card, got error -110
mmcblk1: error -110 requesting status
mmcblk1: recovery failed!
print_req_error: I/O error, dev mmcblk1, sector 0
...

When I remove the '/delete-property/mmc-hs200-1_8v' then everything is hunky dory.

That line comes from the original submission of the mickey dts upstream, so presumably at the time the HS200 was failing and just enumerating things as a high speed device was fine. ...or maybe it's just that some mickey devices work when enumerating at "high speed", just not mine?

In any case, hs200 seems good now. Let's turn it on.

---
 arch/arm/boot/dts/rk3288-veyron-mickey.dts | 4 ----
 1 file changed, 4 deletions(-)

index f36f6f4592257..365382ab9ebdb 100644
@@ -161,10 +161,6 @@
 	};
 };
 
-&emmc {
-	/delete-property/mmc-hs200-1_8v;
-};
-
 &i2c2 {
 	status = "disabled";
 };

2.20.1

[ Upstream commit 8ef1ba39a9fa53d2205e633bc9b21840a275908e ]

This is similar to commit e6186820a745 ("arm64: dts: rockchip: Arch counter doesn't tick in system suspend"). Specifically on the rk3288 it can be seen that the timer stops ticking in suspend if we end up running through the "osc_disable" path in rk3288_slp_mode_set(). In that path the 24 MHz clock will turn off and the timer stops.

To test this, I ran this on a Chrome OS filesystem:
before=$(date); \
suspend_stress_test -c1 --suspend_min=30 --suspend_max=31; \
echo ${before}; date

...and I found that unless I plug in a device that requests USB wakeup to be active that the two calls to "date" would show that fewer than 30 seconds passed.

NOTE: deep suspend (where the 24 MHz clock gets disabled) isn't supported yet on upstream Linux so this was tested on a downstream kernel.

---
 arch/arm/boot/dts/rk3288.dtsi | 1 +
 1 file changed, 1 insertion(+)

index 17ec2e2d7a60b..30f1384f619b3 100644
@@ -210,6 +210,7 @@
 			     <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>,
 			     <GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_HIGH)>;
 		clock-frequency = <24000000>;
+		arm,no-tick-in-suspend;
 	};
 
 	timer: timer@ff810000 {

2.20.1

[ Upstream commit a124692b698b00026a58d89831ceda2331b2e1d0 ]

Custom trampolines can only be enabled if there is only a single ops attached to it. If there's only a single callback registered to a function, and the ops has a trampoline registered for it, then we can call the trampoline directly. This is very useful for improving the performance of ftrace and livepatch.

If more than one callback is registered to a function, the general trampoline is used, and the custom trampoline is not restored back to the direct call even if all the other callbacks were unregistered and we are back to one callback for the function.

To fix this, set FTRACE_FL_TRAMP flag if rec count is decremented to one, and the ops that left has a trampoline.

Testing After this patch :

insmod livepatch_unshare_files.ko
cat /sys/kernel/debug/tracing/enabled_functions

	unshare_files (1) R I	tramp: 0xffffffffc0000000(klp_ftrace_handler+0x0/0xa0) ->ftrace_ops_assist_func+0x0/0xf0

echo unshare_files > /sys/kernel/debug/tracing/set_ftrace_filter echo function > /sys/kernel/debug/tracing/current_tracer cat /sys/kernel/debug/tracing/enabled_functions

	unshare_files (2) R I ->ftrace_ops_list_func+0x0/0x150

echo nop > /sys/kernel/debug/tracing/current_tracer cat /sys/kernel/debug/tracing/enabled_functions

	unshare_files (1) R I	tramp: 0xffffffffc0000000(klp_ftrace_handler+0x0/0xa0) ->ftrace_ops_assist_func+0x0/0xf0

---
 kernel/trace/ftrace.c | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

index 0043aef0ed8dc..77109b9cf7332 100644
@@ -1631,6 +1631,11 @@ static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
 	return  keep_regs;
 }
 
+static struct ftrace_ops *
+ftrace_find_tramp_ops_any(struct dyn_ftrace *rec);
+static struct ftrace_ops *
+ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops);
+
 static bool __ftrace_hash_rec_update(struct ftrace_ops *ops,
 				     int filter_hash,
 				     bool inc)

@@ -1759,15 +1764,17 @@ static bool __ftrace_hash_rec_update(struct ftrace_ops *ops,
 			}
 
 			/*
-			 * If the rec had TRAMP enabled, then it needs to
-			 * be cleared. As TRAMP can only be enabled iff
-			 * there is only a single ops attached to it.
-			 * In otherwords, always disable it on decrementing.
-			 * In the future, we may set it if rec count is
-			 * decremented to one, and the ops that is left
-			 * has a trampoline.
+			 * The TRAMP needs to be set only if rec count
+			 * is decremented to one, and the ops that is
+			 * left has a trampoline. As TRAMP can only be
+			 * enabled if there is only a single ops attached
+			 * to it.
 			 */
-			rec->flags &= ~FTRACE_FL_TRAMP;
+			if (ftrace_rec_count(rec) == 1 &&
+			    ftrace_find_tramp_ops_any(rec))
+				rec->flags |= FTRACE_FL_TRAMP;
+			else
+				rec->flags &= ~FTRACE_FL_TRAMP;
 
 			/*
 			 * flags will be cleared in ftrace_check_record()

@@ -1960,11 +1967,6 @@ static void print_ip_ins(const char *fmt, const unsigned char *p)
 		printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]);
 }
 
-static struct ftrace_ops *
-ftrace_find_tramp_ops_any(struct dyn_ftrace *rec);
-static struct ftrace_ops *
-ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops);
-
 enum ftrace_bug_type ftrace_bug_type;
 const void *ftrace_expected;
 

2.20.1

[ Upstream commit 6e6de3dee51a439f76eb73c22ae2ffd2c9384712 ]

Microsoft HyperV disables the X86_FEATURE_SMCA bit on AMD systems, and linux guests boot with repeated errors:

amd64_edac_mod: Unknown symbol amd_unregister_ecc_decoder (err -2)
amd64_edac_mod: Unknown symbol amd_register_ecc_decoder (err -2)
amd64_edac_mod: Unknown symbol amd_report_gart_errors (err -2)
amd64_edac_mod: Unknown symbol amd_unregister_ecc_decoder (err -2)
amd64_edac_mod: Unknown symbol amd_register_ecc_decoder (err -2)
amd64_edac_mod: Unknown symbol amd_report_gart_errors (err -2)

The warnings occur because the module code erroneously returns -EEXIST for modules that have failed to load and are in the process of being removed from the module list.

module amd64_edac_mod has a dependency on module edac_mce_amd. Using modules.dep, systemd will load edac_mce_amd for every request of amd64_edac_mod. When the edac_mce_amd module loads, the module has state MODULE_STATE_UNFORMED and once the module load fails and the state becomes MODULE_STATE_GOING. Another request for edac_mce_amd module executes and add_unformed_module() will erroneously return -EEXIST even though the previous instance of edac_mce_amd has MODULE_STATE_GOING. Upon receiving -EEXIST, systemd attempts to load amd64_edac_mod, which fails because of unknown symbols from edac_mce_amd.

add_unformed_module() must wait to return for any case other than MODULE_STATE_LIVE to prevent a race between multiple loads of dependent modules.

---
 kernel/module.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

index 2325c9821f2a1..fb9e07aec49e0 100644
@@ -3351,8 +3351,7 @@ static bool finished_loading(const char *name)
 	sched_annotate_sleep();
 	mutex_lock(&module_mutex);
 	mod = find_module_all(name, strlen(name), true);
-	ret = !mod || mod->state == MODULE_STATE_LIVE
-		|| mod->state == MODULE_STATE_GOING;
+	ret = !mod || mod->state == MODULE_STATE_LIVE;
 	mutex_unlock(&module_mutex);
 
 	return ret;

@@ -3515,8 +3514,7 @@ again:
 	mutex_lock(&module_mutex);
 	old = find_module_all(mod->name, strlen(mod->name), true);
 	if (old != NULL) {
-		if (old->state == MODULE_STATE_COMING
-		    || old->state == MODULE_STATE_UNFORMED) {
+		if (old->state != MODULE_STATE_LIVE) {
 			/* Wait in case it fails to load. */
 			mutex_unlock(&module_mutex);
 			err = wait_event_interruptible(module_wq,

2.20.1

[ Upstream commit ba1bc0fcdeaf3bf583c1517bd2e3e29cf223c969 ]

The modification of EXIN register doesn't clean the bitfield before the writing of a new value. After a few modifications the bitfield would accumulate only '1's.

---
 arch/mips/lantiq/irq.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

index 8ac0e5994ed29..7c6f75c2aa4df 100644
@@ -160,8 +160,9 @@ static int ltq_eiu_settype(struct irq_data *d, unsigned int type)
 			if (edge)
 				irq_set_handler(d->hwirq, handle_edge_irq);
 
-			ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_C) |
-				(val << (i * 4)), LTQ_EIU_EXIN_C);
+			ltq_eiu_w32((ltq_eiu_r32(LTQ_EIU_EXIN_C) &
+				    (~(7 << (i * 4)))) | (val << (i * 4)),
+				    LTQ_EIU_EXIN_C);
 		}
 	}
 

2.20.1

[ Upstream commit 78efb76ab4dfb8f74f290ae743f34162cd627f19 ]

While the .device_prep_slave_sg() callback rejects empty scatterlists, it still accepts single-entry scatterlists with a zero-length segment. These may happen if a driver calls dmaengine_prep_slave_single() with a zero len parameter. The corresponding DMA request will never complete, leading to messages like:

rcar-dmac e7300000.dma-controller: Channel Address Error happen

and DMA timeouts.

Although requesting a zero-length DMA request is a driver bug, rejecting it early eases debugging. Note that the .device_prep_dma_memcpy() callback already rejects requests to copy zero bytes.

---
 drivers/dma/sh/rcar-dmac.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index f37a6ef4f5441..e4fe24be3d7a4 100644
@@ -1111,7 +1111,7 @@ rcar_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
 	struct rcar_dmac_chan *rchan = to_rcar_dmac_chan(chan);
 
 	/* Someone calling slave DMA on a generic channel? */
-	if (rchan->mid_rid < 0 || !sg_len) {
+	if (rchan->mid_rid < 0 || !sg_len || !sg_dma_len(sgl)) {
 		dev_warn(chan->device->dev,
 			 "%s: bad parameter: len=%d, id=%d\n",
 			 __func__, sg_len, rchan->mid_rid);

2.20.1

[ Upstream commit 5808b14a1f52554de612fee85ef517199855e310 ]

Fix a use-after-free bug during filesystem initialisation, where we access the disc record (which is stored in a buffer) after we have released the buffer.

---
 fs/adfs/super.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

index c9fdfb1129335..e42c300015090 100644
@@ -368,6 +368,7 @@ static int adfs_fill_super(struct super_block *sb, void *data, int silent)
 	struct buffer_head *bh;
 	struct object_info root_obj;
 	unsigned char *b_data;
+	unsigned int blocksize;
 	struct adfs_sb_info *asb;
 	struct inode *root;
 	int ret = -EINVAL;

@@ -419,8 +420,10 @@ static int adfs_fill_super(struct super_block *sb, void *data, int silent)
 		goto error_free_bh;
 	}
 
+	blocksize = 1 << dr->log2secsize;
 	brelse(bh);
-	if (sb_set_blocksize(sb, 1 << dr->log2secsize)) {
+
+	if (sb_set_blocksize(sb, blocksize)) {
 		bh = sb_bread(sb, ADFS_DISCRECORD / sb->s_blocksize);
 		if (!bh) {
 			adfs_error(sb, "couldn't read superblock on "

2.20.1

[ Upstream commit 0ee5f8ae082e1f675a2fb6db601c31ac9958a134 ]

The list of profiles in btrfs_chunk_max_errors lists DUP as a profile DUP able to tolerate 1 device missing. Though this profile is special with 2 copies, it still needs the device, unlike the others.

Looking at the history of changes, thre's no clear reason why DUP is there, functions were refactored and blocks of code merged to one helper.

d20983b40e828 Btrfs: fix writing data into the seed filesystem
- factor code to a helper

de11cc12df173 Btrfs: don't pre-allocate btrfs bio
- unrelated change, DUP still in the list with max errors 1

a236aed14ccb0 Btrfs: Deal with failed writes in mirrored configurations
- introduced the max errors, leaves DUP and RAID1 in the same group

---
 fs/btrfs/volumes.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

index 94b61afe996c8..70aa22a8a9cce 100644
@@ -5072,8 +5072,7 @@ static inline int btrfs_chunk_max_errors(struct map_lookup *map)
 
 	if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
 			 BTRFS_BLOCK_GROUP_RAID10 |
-			 BTRFS_BLOCK_GROUP_RAID5 |
-			 BTRFS_BLOCK_GROUP_DUP)) {
+			 BTRFS_BLOCK_GROUP_RAID5)) {
 		max_errors = 1;
 	} else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
 		max_errors = 2;

2.20.1

[ Upstream commit 749607731e26dfb2558118038c40e9c0c80d23b5 ]

This barrier only applies to the read-modify-write operations; in particular, it does not apply to the atomic64_set() primitive.

Replace the barrier with an smp_mb().

---
 fs/ceph/super.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

index 622d5dd9f6169..9bd0d928057b7 100644
@@ -476,7 +476,12 @@ static inline void __ceph_dir_set_complete(struct ceph_inode_info *ci,
 					   long long release_count,
 					   long long ordered_count)
 {
-	smp_mb__before_atomic();
+	/*
+	 * Makes sure operations that setup readdir cache (update page
+	 * cache and i_size) are strongly ordered w.r.t. the following
+	 * atomic64_set() operations.
+	 */
+	smp_mb();
 	atomic64_set(&ci->i_complete_seq[0], release_count);
 	atomic64_set(&ci->i_complete_seq[1], ordered_count);
 }

2.20.1

[ Upstream commit 3b421018f48c482bdc9650f894aa1747cf90e51d ]

The getxattr manpage states that we should return ERANGE if the destination buffer size is too small to hold the value. ceph_vxattrcb_layout does this internally, but we should be doing this for all vxattrs.

Fix the only caller of getxattr_cb to check the returned size against the buffer length and return -ERANGE if it doesn't fit. Drop the same check in ceph_vxattrcb_layout and just rely on the caller to handle it.

---
 fs/ceph/xattr.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

index 75267cdd5dfd8..81144a8c09275 100644
@@ -74,7 +74,7 @@ static size_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
 	const char *ns_field = " pool_namespace=";
 	char buf[128];
 	size_t len, total_len = 0;
-	int ret;
+	ssize_t ret;
 
 	pool_ns = ceph_try_get_string(ci->i_layout.pool_ns);
 

@@ -98,11 +98,8 @@ static size_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
 	if (pool_ns)
 		total_len += strlen(ns_field) + pool_ns->len;
 
-	if (!size) {
-		ret = total_len;
-	} else if (total_len > size) {
-		ret = -ERANGE;
-	} else {
+	ret = total_len;
+	if (size >= total_len) {
 		memcpy(val, buf, len);
 		ret = len;
 		if (pool_name) {

@@ -757,8 +754,11 @@ ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 	vxattr = ceph_match_vxattr(inode, name);
 	if (vxattr) {
 		err = -ENODATA;
-		if (!(vxattr->exists_cb && !vxattr->exists_cb(ci)))
+		if (!(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
 			err = vxattr->getxattr_cb(ci, value, size);
+			if (size && size < err)
+				err = -ERANGE;
+		}
 		return err;
 	}
 

2.20.1

[ Upstream commit 484647088826f2f651acbda6bcf9536b8a466703 ]

GCC v9 emits this warning:
CC drivers/s390/scsi/zfcp_erp.o
drivers/s390/scsi/zfcp_erp.c: In function 'zfcp_erp_action_enqueue':
drivers/s390/scsi/zfcp_erp.c:217:26: warning: 'erp_action' may be used uninitialized in this function [-Wmaybe-uninitialized]
217 | struct zfcp_erp_action *erp_action;
| ^~~~~~~~~~

This is a possible false positive case, as also documented in the GCC documentations:
https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wmaybe-uninitialized

The actual code-sequence is like this:

    Various callers can invoke the function below with the argument "want"
    being one of:
    ZFCP_ERP_ACTION_REOPEN_ADAPTER,
    ZFCP_ERP_ACTION_REOPEN_PORT_FORCED,
    ZFCP_ERP_ACTION_REOPEN_PORT, or
    ZFCP_ERP_ACTION_REOPEN_LUN.

    zfcp_erp_action_enqueue(want, ...)
        ...
        need = zfcp_erp_required_act(want, ...)
            need = want
            ...
            maybe: need = ZFCP_ERP_ACTION_REOPEN_PORT
            maybe: need = ZFCP_ERP_ACTION_REOPEN_ADAPTER
            ...
            return need
        ...
        zfcp_erp_setup_act(need, ...)
            struct zfcp_erp_action *erp_action; // <== line 217
            ...
            switch(need) {
            case ZFCP_ERP_ACTION_REOPEN_LUN:
                    ...
                    erp_action = &zfcp_sdev->erp_action;
                    WARN_ON_ONCE(erp_action->port != port); // <== access
                    ...
                    break;
            case ZFCP_ERP_ACTION_REOPEN_PORT:
            case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
                    ...
                    erp_action = &port->erp_action;
                    WARN_ON_ONCE(erp_action->port != port); // <== access
                    ...
                    break;
            case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
                    ...
                    erp_action = &adapter->erp_action;
                    WARN_ON_ONCE(erp_action->port != NULL); // <== access
                    ...
                    break;
            }
            ...
            WARN_ON_ONCE(erp_action->adapter != adapter); // <== access

When zfcp_erp_setup_act() is called, 'need' will never be anything else than one of the 4 possible enumeration-names that are used in the switch-case, and 'erp_action' is initialized for every one of them, before it is used. Thus the warning is a false positive, as documented.

We introduce the extra if{} in the beginning to create an extra code-flow, so the compiler can be convinced that the switch-case will never see any other value.

BUG_ON()/BUG() is intentionally not used to not crash anything, should this ever happen anyway - right now it's impossible, as argued above; and it doesn't introduce a 'default:' switch-case to retain warnings should 'enum zfcp_erp_act_type' ever be extended and no explicit case be introduced. See also v5.0 commit 399b6c8bc9f7 ("scsi: zfcp: drop old default switch case which might paper over missing case").

---
 drivers/s390/scsi/zfcp_erp.c | 7 +++++++
 1 file changed, 7 insertions(+)

index abe460eac7126..cc62d8cc8cfdd 100644
@@ -10,6 +10,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kthread.h>
+#include <linux/bug.h>
 #include "zfcp_ext.h"
 #include "zfcp_reqlist.h"
 

@@ -244,6 +245,12 @@ static struct zfcp_erp_action *zfcp_erp_setup_act(int need, u32 act_status,
 	struct zfcp_erp_action *erp_action;
 	struct zfcp_scsi_dev *zfcp_sdev;
 
+	if (WARN_ON_ONCE(need != ZFCP_ERP_ACTION_REOPEN_LUN &&
+			 need != ZFCP_ERP_ACTION_REOPEN_PORT &&
+			 need != ZFCP_ERP_ACTION_REOPEN_PORT_FORCED &&
+			 need != ZFCP_ERP_ACTION_REOPEN_ADAPTER))
+		return NULL;
+
 	switch (need) {
 	case ZFCP_ERP_ACTION_REOPEN_LUN:
 		zfcp_sdev = sdev_to_zfcp(sdev);

2.20.1

[ Upstream commit dfd6f9ad36368b8dbd5f5a2b2f0a4705ae69a323 ]

clang gets confused by an uninitialized variable in what looks to it like a never executed code path:

arch/x86/kernel/acpi/boot.c:618:13: error: variable 'polarity' is uninitialized when used here [-Werror,-Wuninitialized]

        polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
                   ^~~~~~~~
arch/x86/kernel/acpi/boot.c:606:32: note: initialize the variable 'polarity' to silence this warning
        int rc, irq, trigger, polarity;
                                      ^
                                       = 0
arch/x86/kernel/acpi/boot.c:617:12: error: variable 'trigger' is uninitialized when used here [-Werror,-Wuninitialized]
        trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
                  ^~~~~~~
arch/x86/kernel/acpi/boot.c:606:22: note: initialize the variable 'trigger' to silence this warning
        int rc, irq, trigger, polarity;
                            ^
                             = 0

This is unfortunately a design decision in clang and won't be fixed.

Changing the acpi_get_override_irq() macro to an inline function reliably avoids the issue.

---
 include/linux/acpi.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

index ca2b4c4aec42c..719eb97217a3c 100644
@@ -309,7 +309,10 @@ void acpi_set_irq_model(enum acpi_irq_model_id model,
 #ifdef CONFIG_X86_IO_APIC
 extern int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity);
 #else
-#define acpi_get_override_irq(gsi, trigger, polarity) (-1)
+static inline int acpi_get_override_irq(u32 gsi, int *trigger, int *polarity)
+{
+	return -1;
+}
 #endif
 /*
  * This function undoes the effect of one call to acpi_register_gsi().

2.20.1

[ Upstream commit 7429c6c0d9cb086d8e79f0d2a48ae14851d2115e ]

While changing the number of interrupt channels, be2net stops adapter operation (including netif_tx_disable()) but it doesn't signal that it cannot transmit. This may lead dev_watchdog() to falsely trigger during that time.

Add the missing call to netif_carrier_off(), following the pattern used in many other drivers. netif_carrier_on() is already taken care of in be_open().

---
 drivers/net/ethernet/emulex/benet/be_main.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

index b2eeecb26939b..289560b0f6433 100644
@@ -4701,8 +4701,12 @@ int be_update_queues(struct be_adapter *adapter)
 	struct net_device *netdev = adapter->netdev;
 	int status;
 
-	if (netif_running(netdev))
+	if (netif_running(netdev)) {
+		/* device cannot transmit now, avoid dev_watchdog timeouts */
+		netif_carrier_off(netdev);
+
 		be_close(netdev);
+	}
 
 	be_cancel_worker(adapter);
 

2.20.1

[ Upstream commit ec6335586953b0df32f83ef696002063090c7aef ]

There are many compiler warnings like this,

In file included from ./arch/x86/include/asm/smp.h:13,

                 from ./arch/x86/include/asm/mmzone_64.h:11,
                 from ./arch/x86/include/asm/mmzone.h:5,
                 from ./include/linux/mmzone.h:969,
                 from ./include/linux/gfp.h:6,
                 from ./include/linux/mm.h:10,
                 from arch/x86/kernel/apic/io_apic.c:34:
arch/x86/kernel/apic/io_apic.c: In function 'check_timer':
./arch/x86/include/asm/apic.h:37:11: warning: comparison of unsigned
expression >= 0 is always true [-Wtype-limits]
   if ((v) <= apic_verbosity) \
           ^~

arch/x86/kernel/apic/io_apic.c:2160:2: note: in expansion of macro 'apic_printk'
apic_printk(APIC_QUIET, KERN_INFO "..TIMER: vector=0x%02X " ^~~~~~~~~~~
./arch/x86/include/asm/apic.h:37:11: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]

   if ((v) <= apic_verbosity) \
           ^~

arch/x86/kernel/apic/io_apic.c:2207:4: note: in expansion of macro 'apic_printk'
apic_printk(APIC_QUIET, KERN_ERR "..MP-BIOS bug: " ^~~~~~~~~~~

APIC_QUIET is 0, so silence them by making apic_verbosity type int.

---
 arch/x86/include/asm/apic.h | 2 +-
 arch/x86/kernel/apic/apic.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

index 2188b5af81676..f39fd349cef65 100644
@@ -50,7 +50,7 @@ static inline void generic_apic_probe(void)
 
 #ifdef CONFIG_X86_LOCAL_APIC
 
-extern unsigned int apic_verbosity;
+extern int apic_verbosity;
 extern int local_apic_timer_c2_ok;
 
 extern int disable_apic;

index 4f2af1ee09cbe..cc9a6f680225e 100644
@@ -183,7 +183,7 @@ int first_system_vector = FIRST_SYSTEM_VECTOR;
 /*
  * Debug level, exported for io_apic.c
  */
-unsigned int apic_verbosity;
+int apic_verbosity;
 
 int pic_mode;
 

2.20.1

[ Upstream commit 29e7e9664aec17b94a9c8c5a75f8d216a206aa3a ]

clang warns about a few parts of the math-emu implementation where a 16-bit integer becomes negative during assignment:

arch/x86/math-emu/poly_tan.c:88:35: error: implicit conversion from 'int' to 'short' changes value from 49216 to -16320 [-Werror,-Wconstant-conversion]

                                      (0x41 + EXTENDED_Ebias) | SIGN_Negative);
                                      ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~
arch/x86/math-emu/fpu_emu.h:180:58: note: expanded from macro 'setexponent16'
 #define setexponent16(x,y)  { (*(short *)&((x)->exp)) = (y); }
                                                      ~  ^
arch/x86/math-emu/reg_constant.c:37:32: error: implicit conversion from 'int' to 'short' changes value from 49085 to -16451 [-Werror,-Wconstant-conversion]
FPU_REG const CONST_PI2extra = MAKE_REG(NEG, -66,
                               ^~~~~~~~~~~~~~~~~~
arch/x86/math-emu/reg_constant.c:21:25: note: expanded from macro 'MAKE_REG'
                ((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) }
                 ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/math-emu/reg_constant.c:48:28: error: implicit conversion from 'int' to 'short' changes value from 65535 to -1 [-Werror,-Wconstant-conversion]
FPU_REG const CONST_QNaN = MAKE_REG(NEG, EXP_OVER, 0x00000000, 0xC0000000);
                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/math-emu/reg_constant.c:21:25: note: expanded from macro 'MAKE_REG'
                ((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) }
                 ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

The code is correct as is, so add a typecast to shut up the warnings.

---
 arch/x86/math-emu/fpu_emu.h      | 2 +-
 arch/x86/math-emu/reg_constant.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

index afbc4d805d66f..df5aee5402c44 100644
@@ -176,7 +176,7 @@ static inline void reg_copy(FPU_REG const *x, FPU_REG *y)
 #define setexponentpos(x,y) { (*(short *)&((x)->exp)) = \
   ((y) + EXTENDED_Ebias) & 0x7fff; }
 #define exponent16(x)         (*(short *)&((x)->exp))
-#define setexponent16(x,y)  { (*(short *)&((x)->exp)) = (y); }
+#define setexponent16(x,y)  { (*(short *)&((x)->exp)) = (u16)(y); }
 #define addexponent(x,y)    { (*(short *)&((x)->exp)) += (y); }
 #define stdexp(x)           { (*(short *)&((x)->exp)) += EXTENDED_Ebias; }
 

index 00548354912f4..382093c5072b0 100644
@@ -17,7 +17,7 @@
 #include "control_w.h"
 
 #define MAKE_REG(s, e, l, h) { l, h, \
-		((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) }
+		(u16)((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) }
 
 FPU_REG const CONST_1 = MAKE_REG(POS, 0, 0x00000000, 0x80000000);
 #if 0

2.20.1

[ Upstream commit c633324e311243586675e732249339685e5d6faa ]

The description of cma_declare_contiguous() indicates that if the 'fixed' argument is true the reserved contiguous area must be exactly at the address of the 'base' argument.

However, the function currently allows the 'base', 'size', and 'limit' arguments to be silently adjusted to meet alignment constraints. This commit enforces the documented behavior through explicit checks that return an error if the region does not fit within a specified region.

---
 mm/cma.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

index 4ea0f32761c1a..7cb569a188c48 100644
@@ -268,6 +268,12 @@ int __init cma_declare_contiguous(phys_addr_t base,
 	 */
 	alignment = max(alignment,  (phys_addr_t)PAGE_SIZE <<
 			  max_t(unsigned long, MAX_ORDER - 1, pageblock_order));
+	if (fixed && base & (alignment - 1)) {
+		ret = -EINVAL;
+		pr_err("Region at %pa must be aligned to %pa bytes\n",
+			&base, &alignment);
+		goto err;
+	}
 	base = ALIGN(base, alignment);
 	size = ALIGN(size, alignment);
 	limit &= ~(alignment - 1);

@@ -298,6 +304,13 @@ int __init cma_declare_contiguous(phys_addr_t base,
 	if (limit == 0 || limit > memblock_end)
 		limit = memblock_end;
 
+	if (base + size > limit) {
+		ret = -EINVAL;
+		pr_err("Size (%pa) of region at %pa exceeds limit (%pa)\n",
+			&size, &base, &limit);
+		goto err;
+	}
+
 	/* Reserve memory */
 	if (fixed) {
 		if (memblock_is_region_reserved(base, size) ||

2.20.1

[ Upstream commit 02551c23bcd85f0c68a8259c7b953d49d44f86af ]

When fget fails, the lack of error-handling code may cause unexpected results.

This patch adds error-handling code after calling fget.

---
 fs/coda/psdev.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

index 822629126e89f..ff9b5cf8ff016 100644
@@ -187,8 +187,11 @@ static ssize_t coda_psdev_write(struct file *file, const char __user *buf,
 	if (req->uc_opcode == CODA_OPEN_BY_FD) {
 		struct coda_open_by_fd_out *outp =
 			(struct coda_open_by_fd_out *)req->uc_data;
-		if (!outp->oh.result)
+		if (!outp->oh.result) {
 			outp->fh = fget(outp->fd);
+			if (!outp->fh)
+				return -EBADF;
+		}
 	}
 
         wake_up(&req->uc_sleep);

2.20.1

[ Upstream commit b2a57e334086602be56b74958d9f29b955cd157f ]

The kernel is self-contained project and can be built with bare-metal toolchain. But bare-metal toolchain doesn't define __linux__. Because of this u_quad_t type is not defined when using bare-metal toolchain and codafs build fails. This patch fixes it by defining u_quad_t type unconditionally.

---
 include/linux/coda.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

index d30209b9cef81..0ca0c83fdb1c4 100644
@@ -58,8 +58,7 @@ Mellon the rights to redistribute these changes without encumbrance.
 #ifndef _CODA_HEADER_
 #define _CODA_HEADER_
 
-#if defined(__linux__)
 typedef unsigned long long u_quad_t;
-#endif
+
 #include <uapi/linux/coda.h>
 #endif 

2.20.1

[ Upstream commit f90fb3c7e2c13ae829db2274b88b845a75038b8a ]

Only users of upc_req in kernel side fs/coda/psdev.c and fs/coda/upcall.c already include linux/coda_psdev.h.

Suggested by Jan Harkes <[email protected]> in
https://lore.kernel.org/lkml/[email protected]/

Fixes these include/uapi/linux/coda_psdev.h compilation errors in userspace:

linux/coda_psdev.h:12:19: error: field `uc_chain' has incomplete type

  struct list_head    uc_chain;
                   ^

linux/coda_psdev.h:13:2: error: unknown type name `caddr_t'
caddr_t uc_data;
^
linux/coda_psdev.h:14:2: error: unknown type name `u_short'
u_short uc_flags;
^
linux/coda_psdev.h:15:2: error: unknown type name `u_short'
u_short uc_inSize; /* Size is at most 5000 bytes */
^
linux/coda_psdev.h:16:2: error: unknown type name `u_short'
u_short uc_outSize;
^
linux/coda_psdev.h:17:2: error: unknown type name `u_short'
u_short uc_opcode; /* copied from data to save lookup */
^
linux/coda_psdev.h:19:2: error: unknown type name `wait_queue_head_t'
wait_queue_head_t uc_sleep; /* process' wait queue */
^

---
 include/linux/coda_psdev.h      | 11 +++++++++++
 include/uapi/linux/coda_psdev.h | 13 -------------
 2 files changed, 11 insertions(+), 13 deletions(-)

index 5b8721efa948e..fe1466daf2918 100644
@@ -19,6 +19,17 @@ struct venus_comm {
 	struct mutex	    vc_mutex;
 };
 
+/* messages between coda filesystem in kernel and Venus */
+struct upc_req {
+	struct list_head	uc_chain;
+	caddr_t			uc_data;
+	u_short			uc_flags;
+	u_short			uc_inSize;  /* Size is at most 5000 bytes */
+	u_short			uc_outSize;
+	u_short			uc_opcode;  /* copied from data to save lookup */
+	int			uc_unique;
+	wait_queue_head_t	uc_sleep;   /* process' wait queue */
+};
 
 static inline struct venus_comm *coda_vcp(struct super_block *sb)
 {

index 79d05981fc4b0..e2c44d2f7d5bd 100644
@@ -6,19 +6,6 @@
 #define CODA_PSDEV_MAJOR 67
 #define MAX_CODADEVS  5	   /* how many do we allow */
 
-
-/* messages between coda filesystem in kernel and Venus */
-struct upc_req {
-	struct list_head    uc_chain;
-	caddr_t	            uc_data;
-	u_short	            uc_flags;
-	u_short             uc_inSize;  /* Size is at most 5000 bytes */
-	u_short	            uc_outSize;
-	u_short	            uc_opcode;  /* copied from data to save lookup */
-	int		    uc_unique;
-	wait_queue_head_t   uc_sleep;   /* process' wait queue */
-};
-
 #define CODA_REQ_ASYNC  0x1
 #define CODA_REQ_READ   0x2
 #define CODA_REQ_WRITE  0x4

2.20.1

[ Upstream commit 156e0b1a8112b76e351684ac948c59757037ac36 ]

The dev_info.name[] array has space for RIO_MAX_DEVNAME_SZ + 1 characters. But the problem here is that we don't ensure that the user put a NUL terminator on the end of the string. It could lead to an out of bounds read.

---
 drivers/rapidio/devices/rio_mport_cdev.c | 2 ++
 1 file changed, 2 insertions(+)

index f32fc704cb7ed..28c45db45abad 100644
@@ -1743,6 +1743,7 @@ static int rio_mport_add_riodev(struct mport_cdev_priv *priv,
 
 	if (copy_from_user(&dev_info, arg, sizeof(dev_info)))
 		return -EFAULT;
+	dev_info.name[sizeof(dev_info.name) - 1] = '\0';
 
 	rmcd_debug(RDEV, "name:%s ct:0x%x did:0x%x hc:0x%x", dev_info.name,
 		   dev_info.comptag, dev_info.destid, dev_info.hopcount);

@@ -1874,6 +1875,7 @@ static int rio_mport_del_riodev(struct mport_cdev_priv *priv, void __user *arg)
 
 	if (copy_from_user(&dev_info, arg, sizeof(dev_info)))
 		return -EFAULT;
+	dev_info.name[sizeof(dev_info.name) - 1] = '\0';
 
 	mport = priv->md->mport;
 

2.20.1

[ Upstream commit a318f12ed8843cfac53198390c74a565c632f417 ]

Andreas Christoforou reported:

  UBSAN: Undefined behaviour in ipc/mqueue.c:414:49 signed integer overflow:
  9 * 2305843009213693951 cannot be represented in type 'long int'
  ...
  Call Trace:
    mqueue_evict_inode+0x8e7/0xa10 ipc/mqueue.c:414
    evict+0x472/0x8c0 fs/inode.c:558
    iput_final fs/inode.c:1547 [inline]
    iput+0x51d/0x8c0 fs/inode.c:1573
    mqueue_get_inode+0x8eb/0x1070 ipc/mqueue.c:320
    mqueue_create_attr+0x198/0x440 ipc/mqueue.c:459
    vfs_mkobj+0x39e/0x580 fs/namei.c:2892
    prepare_open ipc/mqueue.c:731 [inline]
    do_mq_open+0x6da/0x8e0 ipc/mqueue.c:771

Which could be triggered by:

        struct mq_attr attr = {
                .mq_flags = 0,
                .mq_maxmsg = 9,
                .mq_msgsize = 0x1fffffffffffffff,
                .mq_curmsgs = 0,
        };

        if (mq_open("/testing", 0x40, 3, &attr) == (mqd_t) -1)
                perror("mq_open");

mqueue_get_inode() was correctly rejecting the giant mq_msgsize, and preparing to return -EINVAL. During the cleanup, it calls mqueue_evict_inode() which performed resource usage tracking math for updating "user", before checking if there was a valid "user" at all (which would indicate that the calculations would be sane). Instead, delay this check to after seeing a valid "user".

The overflow was real, but the results went unused, so while the flaw is harmless, it's noisy for kernel fuzzers, so just fix it by moving the calculation under the non-NULL "user" where it actually gets used.

---
 ipc/mqueue.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

index d5491a8807515..3f7dc5f341f7e 100644
@@ -369,7 +369,6 @@ static void mqueue_evict_inode(struct inode *inode)
 {
 	struct mqueue_inode_info *info;
 	struct user_struct *user;
-	unsigned long mq_bytes, mq_treesize;
 	struct ipc_namespace *ipc_ns;
 	struct msg_msg *msg, *nmsg;
 	LIST_HEAD(tmp_msg);

@@ -392,16 +391,18 @@ static void mqueue_evict_inode(struct inode *inode)
 		free_msg(msg);
 	}
 
-	/* Total amount of bytes accounted for the mqueue */
-	mq_treesize = info->attr.mq_maxmsg * sizeof(struct msg_msg) +
-		min_t(unsigned int, info->attr.mq_maxmsg, MQ_PRIO_MAX) *
-		sizeof(struct posix_msg_tree_node);
-
-	mq_bytes = mq_treesize + (info->attr.mq_maxmsg *
-				  info->attr.mq_msgsize);
-
 	user = info->user;
 	if (user) {
+		unsigned long mq_bytes, mq_treesize;
+
+		/* Total amount of bytes accounted for the mqueue */
+		mq_treesize = info->attr.mq_maxmsg * sizeof(struct msg_msg) +
+			min_t(unsigned int, info->attr.mq_maxmsg, MQ_PRIO_MAX) *
+			sizeof(struct posix_msg_tree_node);
+
+		mq_bytes = mq_treesize + (info->attr.mq_maxmsg *
+					  info->attr.mq_msgsize);
+
 		spin_lock(&mq_lock);
 		user->mq_bytes -= mq_bytes;
 		/*

2.20.1

[ Upstream commit 3901336ed9887b075531bffaeef7742ba614058b ]

After making a change to improve objtool's sibling call detection, it started showing the following warning:

arch/x86/kvm/vmx/nested.o: warning: objtool: .fixup+0x15: sibling call from callable instruction with modified stack frame

The problem is the ____kvm_handle_fault_on_reboot() macro. It does a fake call by pushing a fake RIP and doing a jump. That tricks the unwinder into printing the function which triggered the exception, rather than the .fixup code.

Instead of the hack to make it look like the original function made the call, just change the macro so that the original function actually does make the call. This allows removal of the hack, and also makes objtool happy.

I triggered a vmx instruction exception and verified that the stack trace is still sane:

kernel BUG at arch/x86/kvm/x86.c:358!
invalid opcode: 0000 [#1] SMP PTI

  CPU: 28 PID: 4096 Comm: qemu-kvm Not tainted 5.2.0+ #16
  Hardware name: Lenovo THINKSYSTEM SD530 -[7X2106Z000]-/-[7X2106Z000]-, BIOS -[TEE113Z-1.00]- 07/17/2017
  RIP: 0010:kvm_spurious_fault+0x5/0x10
  Code: 00 00 00 00 00 8b 44 24 10 89 d2 45 89 c9 48 89 44 24 10 8b 44 24 08 48 89 44 24 08 e9 d4 40 22 00 0f 1f 40 00 0f 1f 44 00 00 <0f> 0b 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 55 49 89 fd 41
  RSP: 0018:ffffbf91c683bd00 EFLAGS: 00010246
  RAX: 000061f040000000 RBX: ffff9e159c77bba0 RCX: ffff9e15a5c87000
  RDX: 0000000665c87000 RSI: ffff9e15a5c87000 RDI: ffff9e159c77bba0
  RBP: 0000000000000000 R08: 0000000000000000 R09: ffff9e15a5c87000
  R10: 0000000000000000 R11: fffff8f2d99721c0 R12: ffff9e159c77bba0
  R13: ffffbf91c671d960 R14: ffff9e159c778000 R15: 0000000000000000
  FS:  00007fa341cbe700(0000) GS:ffff9e15b7400000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007fdd38356804 CR3: 00000006759de003 CR4: 00000000007606e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
   loaded_vmcs_init+0x4f/0xe0
   alloc_loaded_vmcs+0x38/0xd0
   vmx_create_vcpu+0xf7/0x600
   kvm_vm_ioctl+0x5e9/0x980
   ? __switch_to_asm+0x40/0x70
   ? __switch_to_asm+0x34/0x70
   ? __switch_to_asm+0x40/0x70
   ? __switch_to_asm+0x34/0x70
   ? free_one_page+0x13f/0x4e0
   do_vfs_ioctl+0xa4/0x630
   ksys_ioctl+0x60/0x90
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x55/0x1c0
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7fa349b1ee5b

---
 arch/x86/include/asm/kvm_host.h | 34 ++++++++++++++++++---------------
 1 file changed, 19 insertions(+), 15 deletions(-)

index 83b5b2990b49a..222cb69e1219d 100644
@@ -1309,25 +1309,29 @@ enum {
 #define kvm_arch_vcpu_memslots_id(vcpu) ((vcpu)->arch.hflags & HF_SMM_MASK ? 1 : 0)
 #define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, (role).smm)
 
+asmlinkage void __noreturn kvm_spurious_fault(void);
+
 /*
  * Hardware virtualization extension instructions may fault if a
  * reboot turns off virtualization while processes are running.
- * Trap the fault and ignore the instruction if that happens.
+ * Usually after catching the fault we just panic; during reboot
+ * instead the instruction is ignored.
  */
-asmlinkage void kvm_spurious_fault(void);
-
-#define ____kvm_handle_fault_on_reboot(insn, cleanup_insn)	\
-	"666: " insn "\n\t" \
-	"668: \n\t"                           \
-	".pushsection .fixup, \"ax\" \n" \
-	"667: \n\t" \
-	cleanup_insn "\n\t"		      \
-	"cmpb $0, kvm_rebooting \n\t"	      \
-	"jne 668b \n\t"      		      \
-	__ASM_SIZE(push) " $666b \n\t"	      \
-	"jmp kvm_spurious_fault \n\t"	      \
-	".popsection \n\t" \
-	_ASM_EXTABLE(666b, 667b)
+#define ____kvm_handle_fault_on_reboot(insn, cleanup_insn)		\
+	"666: \n\t"							\
+	insn "\n\t"							\
+	"jmp	668f \n\t"						\
+	"667: \n\t"							\
+	"call	kvm_spurious_fault \n\t"				\
+	"668: \n\t"							\
+	".pushsection .fixup, \"ax\" \n\t"				\
+	"700: \n\t"							\
+	cleanup_insn "\n\t"						\
+	"cmpb	$0, kvm_rebooting\n\t"					\
+	"je	667b \n\t"						\
+	"jmp	668b \n\t"						\
+	".popsection \n\t"						\
+	_ASM_EXTABLE(666b, 700b)
 
 #define __kvm_handle_fault_on_reboot(insn)		\
 	____kvm_handle_fault_on_reboot(insn, "")

2.20.1

[ Upstream commit 8c5477e8046ca139bac250386c08453da37ec1ae ]

Kernel build warns:
'sanitize_boot_params' defined but not used [-Wunused-function]

at below files:
arch/x86/boot/compressed/cmdline.c
arch/x86/boot/compressed/error.c
arch/x86/boot/compressed/early_serial_console.c
arch/x86/boot/compressed/acpi.c

That's becausethey each include misc.h which includes a definition of sanitize_boot_params() via bootparam_utils.h.

Remove the inclusion from misc.h and have the c file including bootparam_utils.h directly.

---
 arch/x86/boot/compressed/misc.c | 1 +
 arch/x86/boot/compressed/misc.h | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

index d86e68d3c794f..1912b2671f107 100644
@@ -15,6 +15,7 @@
 #include "error.h"
 #include "../string.h"
 #include "../voffset.h"
+#include <asm/bootparam_utils.h>
 
 /*
  * WARNING!!

index 2728e1b7e4a61..a8789aa647b47 100644
@@ -19,7 +19,6 @@
 #include <asm/page.h>
 #include <asm/boot.h>
 #include <asm/bootparam.h>
-#include <asm/bootparam_utils.h>
 
 #define BOOT_BOOT_H
 #include "../ctype.h"

2.20.1

From: Masahiro Yamada <[email protected]>

commit 5241ab4cf42d3a93b933b55d3d53f43049081fa1 upstream.

CLANG_FLAGS is initialized by the following line:

  CLANG_FLAGS     := --target=$(notdir $(CROSS_COMPILE:%-=%))

..., which is run only when CROSS_COMPILE is set.

Some build targets (bindeb-pkg etc.) recurse to the top Makefile.

When you build the kernel with Clang but without CROSS_COMPILE, the same compiler flags such as -no-integrated-as are accumulated into CLANG_FLAGS.

If you run 'make CC=clang' and then 'make CC=clang bindeb-pkg', Kbuild will recompile everything needlessly due to the build command change.

Fix this by correctly initializing CLANG_FLAGS.

---
 Makefile |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

@@ -400,6 +400,7 @@ KBUILD_AFLAGS_MODULE  := -DMODULE
 KBUILD_CFLAGS_MODULE  := -DMODULE
 KBUILD_LDFLAGS_MODULE := -T $(srctree)/scripts/module-common.lds
 GCC_PLUGINS_CFLAGS :=
+CLANG_FLAGS :=
 
 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)

@@ -506,7 +507,7 @@ endif
 
 ifeq ($(cc-name),clang)
 ifneq ($(CROSS_COMPILE),)
-CLANG_FLAGS	:= --target=$(notdir $(CROSS_COMPILE:%-=%))
+CLANG_FLAGS	+= --target=$(notdir $(CROSS_COMPILE:%-=%))
 GCC_TOOLCHAIN_DIR := $(dir $(shell which $(CROSS_COMPILE)elfedit))
 CLANG_FLAGS	+= --prefix=$(GCC_TOOLCHAIN_DIR)
 GCC_TOOLCHAIN	:= $(realpath $(GCC_TOOLCHAIN_DIR)/..)

From: Filipe Manana <[email protected]>

commit b4f9a1a87a48c255bb90d8a6c3d555a1abb88130 upstream.

When doing an incremental send operation we can fail if we previously did deduplication operations against a file that exists in both snapshots. In that case we will fail the send operation with -EIO and print a message to dmesg/syslog like the following:

  BTRFS error (device sdc): Send: inconsistent snapshot, found updated \
  extent for inode 257 without updated inode item, send root is 258, \
  parent root is 257

This requires that we deduplicate to the same file in both snapshots for the same amount of times on each snapshot. The issue happens because a deduplication only updates the iversion of an inode and does not update any other field of the inode, therefore if we deduplicate the file on each snapshot for the same amount of time, the inode will have the same iversion value (stored as the "sequence" field on the inode item) on both snapshots, therefore it will be seen as unchanged between in the send snapshot while there are new/updated/deleted extent items when comparing to the parent snapshot. This makes the send operation return -EIO and print an error message.

Example reproducer:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

# Create our first file. The first half of the file has several 64Kb

  # extents while the second half as a single 512Kb extent.
  $ xfs_io -f -s -c "pwrite -S 0xb8 -b 64K 0 512K" /mnt/foo
  $ xfs_io -c "pwrite -S 0xb8 512K 512K" /mnt/foo

# Create the base snapshot and the parent send stream from it.

  $ btrfs subvolume snapshot -r /mnt /mnt/mysnap1
  $ btrfs send -f /tmp/1.snap /mnt/mysnap1

# Create our second file, that has exactly the same data as the first

  # file.
  $ xfs_io -f -c "pwrite -S 0xb8 0 1M" /mnt/bar

# Create the second snapshot, used for the incremental send, before

  # doing the file deduplication.
  $ btrfs subvolume snapshot -r /mnt /mnt/mysnap2

# Now before creating the incremental send stream:
#
# 1) Deduplicate into a subrange of file foo in snapshot mysnap1. This

  #    will drop several extent items and add a new one, also updating
  #    the inode's iversion (sequence field in inode item) by 1, but not
  #    any other field of the inode;
  #
  # 2) Deduplicate into a different subrange of file foo in snapshot
  #    mysnap2. This will replace an extent item with a new one, also
  #    updating the inode's iversion by 1 but not any other field of the
  #    inode.
  #
  # After these two deduplication operations, the inode items, for file
  # foo, are identical in both snapshots, but we have different extent
  # items for this inode in both snapshots. We want to check this doesn't
  # cause send to fail with an error or produce an incorrect stream.

  $ xfs_io -r -c "dedupe /mnt/bar 0 0 512K" /mnt/mysnap1/foo
  $ xfs_io -r -c "dedupe /mnt/bar 512K 512K 512K" /mnt/mysnap2/foo

# Create the incremental send stream.

  $ btrfs send -p /mnt/mysnap1 -f /tmp/2.snap /mnt/mysnap2
  ERROR: send ioctl failed with -5: Input/output error

This issue started happening back in 2015 when deduplication was updated to not update the inode's ctime and mtime and update only the iversion. Back then we would hit a BUG_ON() in send, but later in 2016 send was updated to return -EIO and print the error message instead of doing the BUG_ON().

A test case for fstests follows soon.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203933

---
 fs/btrfs/send.c |   77 ++++++++++----------------------------------------------
 1 file changed, 15 insertions(+), 62 deletions(-)

@@ -5835,68 +5835,21 @@ static int changed_extent(struct send_ct
 {
 	int ret = 0;
 
-	if (sctx->cur_ino != sctx->cmp_key->objectid) {
-
-		if (result == BTRFS_COMPARE_TREE_CHANGED) {
-			struct extent_buffer *leaf_l;
-			struct extent_buffer *leaf_r;
-			struct btrfs_file_extent_item *ei_l;
-			struct btrfs_file_extent_item *ei_r;
-
-			leaf_l = sctx->left_path->nodes[0];
-			leaf_r = sctx->right_path->nodes[0];
-			ei_l = btrfs_item_ptr(leaf_l,
-					      sctx->left_path->slots[0],
-					      struct btrfs_file_extent_item);
-			ei_r = btrfs_item_ptr(leaf_r,
-					      sctx->right_path->slots[0],
-					      struct btrfs_file_extent_item);
-
-			/*
-			 * We may have found an extent item that has changed
-			 * only its disk_bytenr field and the corresponding
-			 * inode item was not updated. This case happens due to
-			 * very specific timings during relocation when a leaf
-			 * that contains file extent items is COWed while
-			 * relocation is ongoing and its in the stage where it
-			 * updates data pointers. So when this happens we can
-			 * safely ignore it since we know it's the same extent,
-			 * but just at different logical and physical locations
-			 * (when an extent is fully replaced with a new one, we
-			 * know the generation number must have changed too,
-			 * since snapshot creation implies committing the current
-			 * transaction, and the inode item must have been updated
-			 * as well).
-			 * This replacement of the disk_bytenr happens at
-			 * relocation.c:replace_file_extents() through
-			 * relocation.c:btrfs_reloc_cow_block().
-			 */
-			if (btrfs_file_extent_generation(leaf_l, ei_l) ==
-			    btrfs_file_extent_generation(leaf_r, ei_r) &&
-			    btrfs_file_extent_ram_bytes(leaf_l, ei_l) ==
-			    btrfs_file_extent_ram_bytes(leaf_r, ei_r) &&
-			    btrfs_file_extent_compression(leaf_l, ei_l) ==
-			    btrfs_file_extent_compression(leaf_r, ei_r) &&
-			    btrfs_file_extent_encryption(leaf_l, ei_l) ==
-			    btrfs_file_extent_encryption(leaf_r, ei_r) &&
-			    btrfs_file_extent_other_encoding(leaf_l, ei_l) ==
-			    btrfs_file_extent_other_encoding(leaf_r, ei_r) &&
-			    btrfs_file_extent_type(leaf_l, ei_l) ==
-			    btrfs_file_extent_type(leaf_r, ei_r) &&
-			    btrfs_file_extent_disk_bytenr(leaf_l, ei_l) !=
-			    btrfs_file_extent_disk_bytenr(leaf_r, ei_r) &&
-			    btrfs_file_extent_disk_num_bytes(leaf_l, ei_l) ==
-			    btrfs_file_extent_disk_num_bytes(leaf_r, ei_r) &&
-			    btrfs_file_extent_offset(leaf_l, ei_l) ==
-			    btrfs_file_extent_offset(leaf_r, ei_r) &&
-			    btrfs_file_extent_num_bytes(leaf_l, ei_l) ==
-			    btrfs_file_extent_num_bytes(leaf_r, ei_r))
-				return 0;
-		}
-
-		inconsistent_snapshot_error(sctx, result, "extent");
-		return -EIO;
-	}
+	/*
+	 * We have found an extent item that changed without the inode item
+	 * having changed. This can happen either after relocation (where the
+	 * disk_bytenr of an extent item is replaced at
+	 * relocation.c:replace_file_extents()) or after deduplication into a
+	 * file in both the parent and send snapshots (where an extent item can
+	 * get modified or replaced with a new one). Note that deduplication
+	 * updates the inode item, but it only changes the iversion (sequence
+	 * field in the inode item) of the inode, so if a file is deduplicated
+	 * the same amount of times in both the parent and send snapshots, its
+	 * iversion becames the same in both snapshots, whence the inode item is
+	 * the same on both snapshots.
+	 */
+	if (sctx->cur_ino != sctx->cmp_key->objectid)
+		return 0;
 
 	if (!sctx->cur_inode_new_gen && !sctx->cur_inode_deleted) {
 		if (result != BTRFS_COMPARE_TREE_DELETED)

From: Douglas Anderson <[email protected]>

commit ba2d139b02ba684c6c101de42fed782d6cd2b997 upstream.

In commit 46d179525a1f ("mmc: dw_mmc: Wait for data transfer after response errors.") we fixed a tuning-induced hang that I saw when stress testing tuning on certain SD cards. I won't re-hash that whole commit, but the summary is that as a normal part of tuning you need to deal with transfer errors and there were cases where these transfer errors was putting my system into a bad state causing all future transfers to fail. That commit fixed handling of the transfer errors for me.

In downstream Chrome OS my fix landed and had the same behavior for all SD/MMC commands. However, it looks like when the commit landed upstream we limited it to only SD tuning commands. Presumably this was to try to get around problems that Alim Akhtar reported on exynos [1].

Unfortunately while stress testing reboots (and suspend/resume) on some rk3288-based Chromebooks I found the same problem on the eMMC on some of my Chromebooks (the ones with Hynix eMMC). Since the eMMC tuning command is different (MMC_SEND_TUNING_BLOCK_HS200 vs. MMC_SEND_TUNING_BLOCK) we were basically getting back into the same situation.

I'm hoping that whatever problems exynos was having in the past are somehow magically fixed now and we can make the behavior the same for all commands.

[1] https://lkml.kernel.org/r/CAGOxZ53WfNbaMe0_AM0qBqU47kAfgmPBVZC8K8Y-_J3mDMqW4A@mail.gmail.com

---
 drivers/mmc/host/dw_mmc.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

@@ -1864,8 +1864,7 @@ static void dw_mci_tasklet_func(unsigned
 				 * delayed. Allowing the transfer to take place
 				 * avoids races and keeps things simple.
 				 */
-				if ((err != -ETIMEDOUT) &&
-				    (cmd->opcode == MMC_SEND_TUNING_BLOCK)) {
+				if (err != -ETIMEDOUT) {
 					state = STATE_SENDING_DATA;
 					continue;
 				}

From: Michael Wu <[email protected]>

commit 223ecaf140b1dd1c1d2a1a1d96281efc5c906984 upstream.

When a pin is active-low, logical trigger edge should be inverted to match the same interrupt opportunity.

For example, a button pushed triggers falling edge in ACTIVE_HIGH case; in ACTIVE_LOW case, the button pushed triggers rising edge. For user space the IRQ requesting doesn't need to do any modification except to configuring GPIOHANDLE_REQUEST_ACTIVE_LOW.

For example, we want to catch the event when the button is pushed. The button on the original board drives level to be low when it is pushed, and drives level to be high when it is released.

In user space we can do:

	req.handleflags = GPIOHANDLE_REQUEST_INPUT;
	req.eventflags = GPIOEVENT_REQUEST_FALLING_EDGE;

	while (1) {
		read(fd, &dat, sizeof(dat));
		if (dat.id == GPIOEVENT_EVENT_FALLING_EDGE)
			printf("button pushed\n");
	}

Run the same logic on another board which the polarity of the button is inverted; it drives level to be high when pushed, and level to be low when released. For this inversion we add flag GPIOHANDLE_REQUEST_ACTIVE_LOW:

	req.handleflags = GPIOHANDLE_REQUEST_INPUT |
		GPIOHANDLE_REQUEST_ACTIVE_LOW;
	req.eventflags = GPIOEVENT_REQUEST_FALLING_EDGE;

At the result, there are no any events caught when the button is pushed. By the way, button releasing will emit a "falling" event. The timing of "falling" catching is not expected.

---
 drivers/gpio/gpiolib.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

@@ -817,9 +817,11 @@ static int lineevent_create(struct gpio_
 	}
 
 	if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
-		irqflags |= IRQF_TRIGGER_RISING;
+		irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
+			IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
 	if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
-		irqflags |= IRQF_TRIGGER_FALLING;
+		irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
+			IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
 	irqflags |= IRQF_ONESHOT;
 	irqflags |= IRQF_SHARED;
 

From: Ondrej Mosnacek <[email protected]>

commit 45385237f65aeee73641f1ef737d7273905a233f upstream.

Since roles_init() adds some entries to the role hash table, we need to destroy also its keys/values on error, otherwise we get a memory leak in the error path.

---
 security/selinux/ss/policydb.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

@@ -266,6 +266,8 @@ static int rangetr_cmp(struct hashtab *h
 	return v;
 }
 
+static int (*destroy_f[SYM_NUM]) (void *key, void *datum, void *datap);
+
 /*
  * Initialize a policy database structure.
  */

@@ -313,8 +315,10 @@ static int policydb_init(struct policydb
 out:
 	hashtab_destroy(p->filename_trans);
 	hashtab_destroy(p->range_tr);
-	for (i = 0; i < SYM_NUM; i++)
+	for (i = 0; i < SYM_NUM; i++) {
+		hashtab_map(p->symtab[i].table, destroy_f[i], NULL);
 		hashtab_destroy(p->symtab[i].table);
+	}
 	return rc;
 }
 

From: Stefan Haberland <[email protected]>

commit 41995342b40c418a47603e1321256d2c4a2ed0fb upstream.

After getting a storage server event that causes the DASD device driver to update its unit address configuration during a device shutdown there is the possibility of an endless loop in the device driver.

In the system log there will be ongoing DASD error messages with RC: -19.

The reason is that the loop starting the ruac request only terminates when the retry counter is decreased to 0. But in the sleep_on function there are early exit paths that do not decrease the retry counter.

Prevent an endless loop by handling those cases separately.

Remove the unnecessary do..while loop since the sleep_on function takes care of retries by itself.

---
 drivers/s390/block/dasd_alias.c |   22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

@@ -382,6 +382,20 @@ suborder_not_supported(struct dasd_ccw_r
 	char msg_format;
 	char msg_no;
 
+	/*
+	 * intrc values ENODEV, ENOLINK and EPERM
+	 * will be optained from sleep_on to indicate that no
+	 * IO operation can be started
+	 */
+	if (cqr->intrc == -ENODEV)
+		return 1;
+
+	if (cqr->intrc == -ENOLINK)
+		return 1;
+
+	if (cqr->intrc == -EPERM)
+		return 1;
+
 	sense = dasd_get_sense(&cqr->irb);
 	if (!sense)
 		return 0;

@@ -446,12 +460,8 @@ static int read_unit_address_configurati
 	lcu->flags &= ~NEED_UAC_UPDATE;
 	spin_unlock_irqrestore(&lcu->lock, flags);
 
-	do {
-		rc = dasd_sleep_on(cqr);
-		if (rc && suborder_not_supported(cqr))
-			return -EOPNOTSUPP;
-	} while (rc && (cqr->retries > 0));
-	if (rc) {
+	rc = dasd_sleep_on(cqr);
+	if (rc && !suborder_not_supported(cqr)) {
 		spin_lock_irqsave(&lcu->lock, flags);
 		lcu->flags |= NEED_UAC_UPDATE;
 		spin_unlock_irqrestore(&lcu->lock, flags);

From: Will Deacon <[email protected]>

commit 0d7fd70f26039bd4b33444ca47f0e69ce3ae0354 upstream.

Handling of the CPU_PM_ENTER_FAILED transition in the Arm PMU PM notifier code incorrectly skips restoration of the counters. Fix the logic so that CPU_PM_ENTER_FAILED follows the same path as CPU_PM_EXIT.

---
 drivers/perf/arm_pmu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -804,8 +804,8 @@ static int cpu_pm_pmu_notify(struct noti
 		cpu_pm_pmu_setup(armpmu, cmd);
 		break;
 	case CPU_PM_EXIT:
-		cpu_pm_pmu_setup(armpmu, cmd);
 	case CPU_PM_ENTER_FAILED:
+		cpu_pm_pmu_setup(armpmu, cmd);
 		armpmu->start(armpmu);
 		break;
 	default:

From: Juergen Gross <[email protected]>

commit 50f6393f9654c561df4cdcf8e6cfba7260143601 upstream.

The condition in xen_swiotlb_free_coherent() for deciding whether to call xen_destroy_contiguous_region() is wrong: in case the region to be freed is not contiguous calling xen_destroy_contiguous_region() is the wrong thing to do: it would result in inconsistent mappings of multiple PFNs to the same MFN. This will lead to various strange crashes or data corruption.

Instead of calling xen_destroy_contiguous_region() in that case a warning should be issued as that situation should never occur.

---
 drivers/xen/swiotlb-xen.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -365,8 +365,8 @@ xen_swiotlb_free_coherent(struct device
 	/* Convert the size to actually allocated. */
 	size = 1UL << (order + XEN_PAGE_SHIFT);
 
-	if (((dev_addr + size - 1 <= dma_mask)) ||
-	    range_straddles_page_boundary(phys, size))
+	if (!WARN_ON((dev_addr + size - 1 > dma_mask) ||
+		     range_straddles_page_boundary(phys, size)))
 		xen_destroy_contiguous_region(phys, order);
 
 	xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs);

From: Yishai Hadas <[email protected]>

commit b7165bd0d6cbb93732559be6ea8774653b204480 upstream.

The specification for the Toeplitz function doesn't require to set the key explicitly to be symmetric. In case a symmetric functionality is required a symmetric key can be simply used.

Wrongly forcing the algorithm to symmetric causes the wrong packet distribution and a performance degradation.

---
 drivers/infiniband/hw/mlx5/qp.c |    1 -
 1 file changed, 1 deletion(-)

@@ -1421,7 +1421,6 @@ static int create_rss_raw_qp_tir(struct
 		}
 
 		MLX5_SET(tirc, tirc, rx_hash_fn, MLX5_RX_HASH_FN_TOEPLITZ);
-		MLX5_SET(tirc, tirc, rx_hash_symmetric, 1);
 		memcpy(rss_key, ucmd.rx_hash_key, len);
 		break;
 	}

From: Andrea Arcangeli <[email protected]>

commit 04f5866e41fb70690e28397487d8bd8eea7d712a upstream.

The core dumping code has always run without holding the mmap_sem for writing, despite that is the only way to ensure that the entire vma layout will not change from under it. Only using some signal serialization on the processes belonging to the mm is not nearly enough. This was pointed out earlier. For example in Hugh's post from Jul 2017:

https://lkml.kernel.org/r/[email protected]

"Not strictly relevant here, but a related note: I was very surprised
to discover, only quite recently, how handle_mm_fault() may be called without down_read(mmap_sem) - when core dumping. That seems a misguided optimization to me, which would also be nice to correct"

In particular because the growsdown and growsup can move the vm_start/vm_end the various loops the core dump does around the vma will not be consistent if page faults can happen concurrently.

Pretty much all users calling mmget_not_zero()/get_task_mm() and then taking the mmap_sem had the potential to introduce unexpected side effects in the core dumping code.

Adding mmap_sem for writing around the ->core_dump invocation is a viable long term fix, but it requires removing all copy user and page faults and to replace them with get_dump_page() for all binary formats which is not suitable as a short term fix.

For the time being this solution manually covers the places that can confuse the core dump either by altering the vma layout or the vma flags while it runs. Once ->core_dump runs under mmap_sem for writing the function mmget_still_valid() can be dropped.

Allowing mmap_sem protected sections to run in parallel with the coredump provides some minor parallelism advantage to the swapoff code (which seems to be safe enough by never mangling any vma field and can keep doing swapins in parallel to the core dumping) and to some other corner case.

In order to facilitate the backporting I added "Fixes: 86039bd3b4e6" however the side effect of this same race condition in /proc/pid/mem should be reproducible since before 2.6.12-rc2 so I couldn't add any other "Fixes:" because there's no hash beyond the git genesis commit.

Because find_extend_vma() is the only location outside of the process context that could modify the "mm" structures under mmap_sem for reading, by adding the mmget_still_valid() check to it, all other cases that take the mmap_sem for reading don't need the new check after mmget_not_zero()/get_task_mm(). The expand_stack() in page fault context also doesn't need the new check, because all tasks under core dumping are frozen.

[[email protected]: stable 4.9 backport
- handle binder_update_page_range - [email protected]]

---
 drivers/android/binder.c |    6 ++++++
 fs/proc/task_mmu.c       |   18 ++++++++++++++++++
 fs/userfaultfd.c         |    9 +++++++++
 include/linux/mm.h       |   20 ++++++++++++++++++++
 mm/mmap.c                |    6 +++++-
 5 files changed, 58 insertions(+), 1 deletion(-)

@@ -581,6 +581,12 @@ static int binder_update_page_range(stru
 
 	if (mm) {
 		down_write(&mm->mmap_sem);
+		if (!mmget_still_valid(mm)) {
+			if (allocate == 0)
+				goto free_range;
+			goto err_no_vma;
+		}
+
 		vma = proc->vma;
 		if (vma && mm != proc->vma_vm_mm) {
 			pr_err("%d: vma mm and task mm mismatch\n",

@@ -1057,6 +1057,24 @@ static ssize_t clear_refs_write(struct f
 					count = -EINTR;
 					goto out_mm;
 				}
+				/*
+				 * Avoid to modify vma->vm_flags
+				 * without locked ops while the
+				 * coredump reads the vm_flags.
+				 */
+				if (!mmget_still_valid(mm)) {
+					/*
+					 * Silently return "count"
+					 * like if get_task_mm()
+					 * failed. FIXME: should this
+					 * function have returned
+					 * -ESRCH if get_task_mm()
+					 * failed like if
+					 * get_proc_task() fails?
+					 */
+					up_write(&mm->mmap_sem);
+					goto out_mm;
+				}
 				for (vma = mm->mmap; vma; vma = vma->vm_next) {
 					vma->vm_flags &= ~VM_SOFTDIRTY;
 					vma_set_page_prot(vma);

@@ -479,6 +479,8 @@ static int userfaultfd_release(struct in
 	 * taking the mmap_sem for writing.
 	 */
 	down_write(&mm->mmap_sem);
+	if (!mmget_still_valid(mm))
+		goto skip_mm;
 	prev = NULL;
 	for (vma = mm->mmap; vma; vma = vma->vm_next) {
 		cond_resched();

@@ -501,6 +503,7 @@ static int userfaultfd_release(struct in
 		vma->vm_flags = new_flags;
 		vma->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
 	}
+skip_mm:
 	up_write(&mm->mmap_sem);
 	mmput(mm);
 wakeup:

@@ -802,6 +805,9 @@ static int userfaultfd_register(struct u
 		goto out;
 
 	down_write(&mm->mmap_sem);
+	if (!mmget_still_valid(mm))
+		goto out_unlock;
+
 	vma = find_vma_prev(mm, start, &prev);
 	if (!vma)
 		goto out_unlock;

@@ -947,6 +953,9 @@ static int userfaultfd_unregister(struct
 		goto out;
 
 	down_write(&mm->mmap_sem);
+	if (!mmget_still_valid(mm))
+		goto out_unlock;
+
 	vma = find_vma_prev(mm, start, &prev);
 	if (!vma)
 		goto out_unlock;

@@ -1192,6 +1192,26 @@ void zap_page_range(struct vm_area_struc
 		unsigned long size, struct zap_details *);
 void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma,
 		unsigned long start, unsigned long end);
+/*
+ * This has to be called after a get_task_mm()/mmget_not_zero()
+ * followed by taking the mmap_sem for writing before modifying the
+ * vmas or anything the coredump pretends not to change from under it.
+ *
+ * NOTE: find_extend_vma() called from GUP context is the only place
+ * that can modify the "mm" (notably the vm_start/end) under mmap_sem
+ * for reading and outside the context of the process, so it is also
+ * the only case that holds the mmap_sem for reading that must call
+ * this function. Generally if the mmap_sem is hold for reading
+ * there's no need of this check after get_task_mm()/mmget_not_zero().
+ *
+ * This function can be obsoleted and the check can be removed, after
+ * the coredump code will hold the mmap_sem for writing before
+ * invoking the ->core_dump methods.
+ */
+static inline bool mmget_still_valid(struct mm_struct *mm)
+{
+	return likely(!mm->core_state);
+}
 
 /**
  * mm_walk - callbacks for walk_page_range

@@ -2448,7 +2448,8 @@ find_extend_vma(struct mm_struct *mm, un
 	vma = find_vma_prev(mm, addr, &prev);
 	if (vma && (vma->vm_start <= addr))
 		return vma;
-	if (!prev || expand_stack(prev, addr))
+	/* don't alter vm_end if the coredump is running */
+	if (!prev || !mmget_still_valid(mm) || expand_stack(prev, addr))
 		return NULL;
 	if (prev->vm_flags & VM_LOCKED)
 		populate_vma_page_range(prev, addr, prev->vm_end, NULL);

@@ -2474,6 +2475,9 @@ find_extend_vma(struct mm_struct *mm, un
 		return vma;
 	if (!(vma->vm_flags & VM_GROWSDOWN))
 		return NULL;
+	/* don't alter vm_start if the coredump is running */
+	if (!mmget_still_valid(mm))
+		return NULL;
 	start = vma->vm_start;
 	if (expand_stack(vma, addr))
 		return NULL;

From: Ajay Kaher <[email protected]>

This patch is the extension of following upstream commit to fix the race condition between get_task_mm() and core dumping for IB->mlx4 and IB->mlx5 drivers:

commit 04f5866e41fb ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping")'

Thanks to Jason for pointing this.

---
 drivers/infiniband/hw/mlx4/main.c |    4 +++-
 drivers/infiniband/hw/mlx5/main.c |    3 +++
 2 files changed, 6 insertions(+), 1 deletion(-)

@@ -1172,6 +1172,8 @@ static void mlx4_ib_disassociate_ucontex
 	 * mlx4_ib_vma_close().
 	 */
 	down_write(&owning_mm->mmap_sem);
+	if (!mmget_still_valid(owning_mm))
+		goto skip_mm;
 	for (i = 0; i < HW_BAR_COUNT; i++) {
 		vma = context->hw_bar_info[i].vma;
 		if (!vma)

@@ -1190,7 +1192,7 @@ static void mlx4_ib_disassociate_ucontex
 		/* context going to be destroyed, should not access ops any more */
 		context->hw_bar_info[i].vma->vm_ops = NULL;
 	}
-
+skip_mm:
 	up_write(&owning_mm->mmap_sem);
 	mmput(owning_mm);
 	put_task_struct(owning_process);

@@ -1307,6 +1307,8 @@ static void mlx5_ib_disassociate_ucontex
 	 * mlx5_ib_vma_close.
 	 */
 	down_write(&owning_mm->mmap_sem);
+	if (!mmget_still_valid(owning_mm))
+		goto skip_mm;
 	list_for_each_entry_safe(vma_private, n, &context->vma_private_list,
 				 list) {
 		vma = vma_private->vma;

@@ -1321,6 +1323,7 @@ static void mlx5_ib_disassociate_ucontex
 		list_del(&vma_private->list);
 		kfree(vma_private);
 	}
+skip_mm:
 	up_write(&owning_mm->mmap_sem);
 	mmput(owning_mm);
 	put_task_struct(owning_process);

From: Andrea Arcangeli <[email protected]>

commit 59ea6d06cfa9247b586a695c21f94afa7183af74 upstream.

When fixing the race conditions between the coredump and the mmap_sem holders outside the context of the process, we focused on mmget_not_zero()/get_task_mm() callers in 04f5866e41fb70 ("coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping"), but those aren't the only cases where the mmap_sem can be taken outside of the context of the process as Michal Hocko noticed while backporting that commit to older -stable kernels.

If mmgrab() is called in the context of the process, but then the mm_count reference is transferred outside the context of the process, that can also be a problem if the mmap_sem has to be taken for writing through that mm_count reference.

khugepaged registration calls mmgrab() in the context of the process, but the mmap_sem for writing is taken later in the context of the khugepaged kernel thread.

collapse_huge_page() after taking the mmap_sem for writing doesn't modify any vma, so it's not obvious that it could cause a problem to the coredump, but it happens to modify the pmd in a way that breaks an invariant that pmd_trans_huge_lock() relies upon. collapse_huge_page() needs the mmap_sem for writing just to block concurrent page faults that call pmd_trans_huge_lock().

Specifically the invariant that "!pmd_trans_huge()" cannot become a "pmd_trans_huge()" doesn't hold while collapse_huge_page() runs.

The coredump will call __get_user_pages() without mmap_sem for reading, which eventually can invoke a lockless page fault which will need a functional pmd_trans_huge_lock().

So collapse_huge_page() needs to use mmget_still_valid() to check it's not running concurrently with the coredump... as long as the coredump can invoke page faults without holding the mmap_sem for reading.

This has "Fixes: khugepaged" to facilitate backporting, but in my view it's more a bug in the coredump code that will eventually have to be rewritten to stop invoking page faults without the mmap_sem for reading. So the long term plan is still to drop all mmget_still_valid().

---
 include/linux/mm.h |    4 ++++
 mm/khugepaged.c    |    3 +++
 2 files changed, 7 insertions(+)

@@ -1197,6 +1197,10 @@ void unmap_vmas(struct mmu_gather *tlb,
  * followed by taking the mmap_sem for writing before modifying the
  * vmas or anything the coredump pretends not to change from under it.
  *
+ * It also has to be called when mmgrab() is used in the context of
+ * the process, but then the mm_count refcount is transferred outside
+ * the context of the process to run down_write() on that pinned mm.
+ *
  * NOTE: find_extend_vma() called from GUP context is the only place
  * that can modify the "mm" (notably the vm_start/end) under mmap_sem
  * for reading and outside the context of the process, so it is also

@@ -1004,6 +1004,9 @@ static void collapse_huge_page(struct mm
 	 * handled by the anon_vma lock + PG_lock.
 	 */
 	down_write(&mm->mmap_sem);
+	result = SCAN_ANY_PROCESS;
+	if (!mmget_still_valid(mm))
+		goto out;
 	result = hugepage_vma_revalidate(mm, address, &vma);
 	if (result)
 		goto out;

From: Jean Delvare <[email protected]>

commit 25e5ef302c24a6fead369c0cfe88c073d7b97ca8 upstream.

The integration of the at24 driver into the nvmem framework broke the world-readability of spd EEPROMs. Fix it.

---
 drivers/misc/eeprom/at24.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -777,7 +777,7 @@ static int at24_probe(struct i2c_client
 	at24->nvmem_config.name = dev_name(&client->dev);
 	at24->nvmem_config.dev = &client->dev;
 	at24->nvmem_config.read_only = !writable;
-	at24->nvmem_config.root_only = true;
+	at24->nvmem_config.root_only = !(chip.flags & AT24_FLAG_IRUGO);
 	at24->nvmem_config.owner = THIS_MODULE;
 	at24->nvmem_config.compat = true;
 	at24->nvmem_config.base_dev = &client->dev;

From: Miguel Ojeda <[email protected]>

This adds support for __copy to v4.9.y so that we can use it in init/exit_module to avoid -Werror=missing-attributes errors on GCC 9.

---
 include/linux/compiler.h |   16 ++++++++++++++++
 1 file changed, 16 insertions(+)

@@ -54,6 +54,22 @@ extern void __chk_io_ptr(const volatile
 
 #ifdef __KERNEL__
 
+/*
+ * Minimal backport of compiler_attributes.h to add support for __copy
+ * to v4.9.y so that we can use it in init/exit_module to avoid
+ * -Werror=missing-attributes errors on GCC 9.
+ */
+#ifndef __has_attribute
+# define __has_attribute(x) __GCC4_has_attribute_##x
+# define __GCC4_has_attribute___copy__                0
+#endif
+
+#if __has_attribute(__copy__)
+# define __copy(symbol)                 __attribute__((__copy__(symbol)))
+#else
+# define __copy(symbol)
+#endif
+
 #ifdef __GNUC__
 #include <linux/compiler-gcc.h>
 #endif

From: Miguel Ojeda <[email protected]>

commit a6e60d84989fa0e91db7f236eda40453b0e44afa upstream.

The upcoming GCC 9 release extends the -Wmissing-attributes warnings (enabled by -Wall) to C and aliases: it warns when particular function attributes are missing in the aliases but not in their target.

In particular, it triggers for all the init/cleanup_module aliases in the kernel (defined by the module_init/exit macros), ending up being very noisy.

These aliases point to the __init/__exit functions of a module, which are defined as __cold (among other attributes). However, the aliases themselves do not have the __cold attribute.

Since the compiler behaves differently when compiling a __cold function as well as when compiling paths leading to calls to __cold functions, the warning is trying to point out the possibly-forgotten attribute in the alias.

In order to keep the warning enabled, we decided to silence this case. Ideally, we would mark the aliases directly as __init/__exit. However, there are currently around 132 modules in the kernel which are missing __init/__exit in their init/cleanup functions (either because they are missing, or for other reasons, e.g. the functions being called from somewhere else); and a section mismatch is a hard error.

A conservative alternative was to mark the aliases as __cold only. However, since we would like to eventually enforce __init/__exit to be always marked, we chose to use the new __copy function attribute (introduced by GCC 9 as well to deal with this). With it, we copy the attributes used by the target functions into the aliases. This way, functions that were not marked as __init/__exit won't have their aliases marked either, and therefore there won't be a section mismatch.

Note that the warning would go away marking either the extern declaration, the definition, or both. However, we only mark the definition of the alias, since we do not want callers (which only see the declaration) to be compiled as if the function was __cold (and therefore the paths leading to those calls would be assumed to be unlikely).

---
 include/linux/module.h |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -129,13 +129,13 @@ extern void cleanup_module(void);
 #define module_init(initfn)					\
 	static inline initcall_t __maybe_unused __inittest(void)		\
 	{ return initfn; }					\
-	int init_module(void) __attribute__((alias(#initfn)));
+	int init_module(void) __copy(initfn) __attribute__((alias(#initfn)));
 
 /* This is only required if you want to be unloadable. */
 #define module_exit(exitfn)					\
 	static inline exitcall_t __maybe_unused __exittest(void)		\
 	{ return exitfn; }					\
-	void cleanup_module(void) __attribute__((alias(#exitfn)));
+	void cleanup_module(void) __copy(exitfn) __attribute__((alias(#exitfn)));
 
 #endif
 

From: Josh Poimboeuf <[email protected]>

commit bcb6fb5da77c2a228adf07cc9cb1a0c2aa2001c6 upstream.

Starting with GCC 8, a lot of unlikely code was moved out of line to "cold" subfunctions in .text.unlikely.

For example, the unlikely bits of:

irq_do_set_affinity()

are moved out to the following subfunction:

irq_do_set_affinity.cold.49()

Starting with GCC 9, the numbered suffix has been removed. So in the above example, the cold subfunction is instead:

irq_do_set_affinity.cold()

Tweak the objtool subfunction detection logic so that it detects both GCC 8 and GCC 9 naming schemes.

---
 tools/objtool/elf.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -305,7 +305,7 @@ static int read_symbols(struct elf *elf)
 			if (sym->type != STT_FUNC)
 				continue;
 			sym->pfunc = sym->cfunc = sym;
-			coldstr = strstr(sym->name, ".cold.");
+			coldstr = strstr(sym->name, ".cold");
 			if (!coldstr)
 				continue;
 

From: Vlastimil Babka <[email protected]>

The x86 version of get_user_pages_fast() relies on disabled interrupts to synchronize gup_pte_range() between gup_get_pte(ptep); and get_page() against a parallel munmap. The munmap side nulls the pte, then flushes TLBs, then releases the page. As TLB flush is done synchronously via IPI disabling interrupts blocks the page release, and get_page(), which assumes existing reference on page, is thus safe.
However when TLB flush is done by a hypercall, e.g. in a Xen PV guest, there is no blocking thanks to disabled interrupts, and get_page() can succeed on a page that was already freed or even reused.

We have recently seen this happen with our 4.4 and 4.12 based kernels, with userspace (java) that exits a thread, where mm_release() performs a futex_wake() on tsk->clear_child_tid, and another thread in parallel unmaps the page where tsk->clear_child_tid points to. The spurious get_page() succeeds, but futex code immediately releases the page again, while it's already on a freelist. Symptoms include a bad page state warning, general protection faults acessing a poisoned list prev/next pointer in the freelist, or free page pcplists of two cpus joined together in a single list. Oscar has also reproduced this scenario, with a patch inserting delays before the get_page() to make the race window larger.

Fix this by removing the dependency on TLB flush interrupts the same way as the generic get_user_pages_fast() code by using page_cache_add_speculative() and revalidating the PTE contents after pinning the page. Mainline is safe since 4.13 where the x86 gup code was removed in favor of the common code. Accessing the page table itself safely also relies on disabled interrupts and TLB flush IPIs that don't happen with hypercalls, which was acknowledged in commit 9e52fc2b50de ("x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)"). That commit with follups should also be backported for full safety, although our reproducer didn't hit a problem without that backport.

---

---
 arch/x86/mm/gup.c |   32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

@@ -98,6 +98,20 @@ static inline int pte_allows_gup(unsigne
 }
 
 /*
+ * Return the compund head page with ref appropriately incremented,
+ * or NULL if that failed.
+ */
+static inline struct page *try_get_compound_head(struct page *page, int refs)
+{
+	struct page *head = compound_head(page);
+	if (WARN_ON_ONCE(page_ref_count(head) < 0))
+		return NULL;
+	if (unlikely(!page_cache_add_speculative(head, refs)))
+		return NULL;
+	return head;
+}
+
+/*
  * The performance critical leaf functions are made noinline otherwise gcc
  * inlines everything into a single function which results in too much
  * register pressure.

@@ -112,7 +126,7 @@ static noinline int gup_pte_range(pmd_t
 	ptep = pte_offset_map(&pmd, addr);
 	do {
 		pte_t pte = gup_get_pte(ptep);
-		struct page *page;
+		struct page *head, *page;
 
 		/* Similar to the PMD case, NUMA hinting must take slow path */
 		if (pte_protnone(pte)) {

@@ -138,7 +152,21 @@ static noinline int gup_pte_range(pmd_t
 		}
 		VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
 		page = pte_page(pte);
-		get_page(page);
+
+		head = try_get_compound_head(page, 1);
+		if (!head) {
+			put_dev_pagemap(pgmap);
+			pte_unmap(ptep);
+			return 0;
+		}
+
+		if (unlikely(pte_val(pte) != pte_val(*ptep))) {
+			put_page(head);
+			put_dev_pagemap(pgmap);
+			pte_unmap(ptep);
+			return 0;
+		}
+
 		put_dev_pagemap(pgmap);
 		SetPageReferenced(page);
 		pages[*nr] = page;

Peter Zijlstra's "x86/atomic: Fix smp_mb__{before,after}_atomic()" upstream commit 69d927bba39517d0980462efc051875b7f4db185 seems to be missing/lost from 4.9 and older stable kernels.

That patch has 10 hunks, first one of those does not apply cleanly to 4.9 kernel because it attempts to modify Documentation/atomic_t.txt file which does not exist in older kernels. Other 9 hunks apply with small offsets and fuzz, but modifications find their correct places anyway. Those other 9 hunks are the important ones, first hunk can be ignored.

Greg,
Please take Peter Zijlstra's original patch and "force" apply it like this to 4.9 kernels:

patch -p1 -f <ORIGINAL.patch

and for 4.4 kernels like this:

cat ORIGINAL.patch | sed -e 's/__smp_mb__/smp_mb__/' | patch -p1 -f -l

Jari Ruusu  4096R/8132F189 12D6 4C3A DCDA 0AA4 27BD  ACDF F073 3C80 8132 F189

Can you send properly backported and tested patches?

thanks,

greg k-h

linux-4.9 backport of "x86/atomic: Fix smp_mb__{before,after}_atomic()". Tested.

@@ -49,7 +49,7 @@
 {
 	asm volatile(LOCK_PREFIX "addl %1,%0"
 		     : "+m" (v->counter)
-		     : "ir" (i));
+		     : "ir" (i) : "memory");
 }
 
 /**

@@ -63,7 +63,7 @@
 {
 	asm volatile(LOCK_PREFIX "subl %1,%0"
 		     : "+m" (v->counter)
-		     : "ir" (i));
+		     : "ir" (i) : "memory");
 }
 
 /**

@@ -89,7 +89,7 @@
 static __always_inline void atomic_inc(atomic_t *v)
 {
 	asm volatile(LOCK_PREFIX "incl %0"
-		     : "+m" (v->counter));
+		     : "+m" (v->counter) :: "memory");
 }
 
 /**

@@ -101,7 +101,7 @@
 static __always_inline void atomic_dec(atomic_t *v)
 {
 	asm volatile(LOCK_PREFIX "decl %0"
-		     : "+m" (v->counter));
+		     : "+m" (v->counter) :: "memory");
 }
 
 /**

@@ -44,7 +44,7 @@
 {
 	asm volatile(LOCK_PREFIX "addq %1,%0"
 		     : "=m" (v->counter)
-		     : "er" (i), "m" (v->counter));
+		     : "er" (i), "m" (v->counter) : "memory");
 }
 
 /**

@@ -58,7 +58,7 @@
 {
 	asm volatile(LOCK_PREFIX "subq %1,%0"
 		     : "=m" (v->counter)
-		     : "er" (i), "m" (v->counter));
+		     : "er" (i), "m" (v->counter) : "memory");
 }
 
 /**

@@ -85,7 +85,7 @@
 {
 	asm volatile(LOCK_PREFIX "incq %0"
 		     : "=m" (v->counter)
-		     : "m" (v->counter));
+		     : "m" (v->counter) : "memory");
 }
 
 /**

@@ -98,7 +98,7 @@
 {
 	asm volatile(LOCK_PREFIX "decq %0"
 		     : "=m" (v->counter)
-		     : "m" (v->counter));
+		     : "m" (v->counter) : "memory");
 }
 
 /**

@@ -105,8 +105,8 @@
 #endif
 
 /* Atomic operations are already serializing on x86 */
-#define __smp_mb__before_atomic()	barrier()
-#define __smp_mb__after_atomic()	barrier()
+#define __smp_mb__before_atomic()	do { } while (0)
+#define __smp_mb__after_atomic()	do { } while (0)
 
 #include <asm-generic/barrier.h>
 

Jari Ruusu  4096R/8132F189 12D6 4C3A DCDA 0AA4 27BD  ACDF F073 3C80 8132 F189

linux-4.4 backport of "x86/atomic: Fix smp_mb__{before,after}_atomic()". Tested.

@@ -49,7 +49,7 @@
 {
 	asm volatile(LOCK_PREFIX "addl %1,%0"
 		     : "+m" (v->counter)
-		     : "ir" (i));
+		     : "ir" (i) : "memory");
 }
 
 /**

@@ -63,7 +63,7 @@
 {
 	asm volatile(LOCK_PREFIX "subl %1,%0"
 		     : "+m" (v->counter)
-		     : "ir" (i));
+		     : "ir" (i) : "memory");
 }
 
 /**

@@ -89,7 +89,7 @@
 static __always_inline void atomic_inc(atomic_t *v)
 {
 	asm volatile(LOCK_PREFIX "incl %0"
-		     : "+m" (v->counter));
+		     : "+m" (v->counter) :: "memory");
 }
 
 /**

@@ -101,7 +101,7 @@
 static __always_inline void atomic_dec(atomic_t *v)
 {
 	asm volatile(LOCK_PREFIX "decl %0"
-		     : "+m" (v->counter));
+		     : "+m" (v->counter) :: "memory");
 }
 
 /**

@@ -44,7 +44,7 @@
 {
 	asm volatile(LOCK_PREFIX "addq %1,%0"
 		     : "=m" (v->counter)
-		     : "er" (i), "m" (v->counter));
+		     : "er" (i), "m" (v->counter) : "memory");
 }
 
 /**

@@ -58,7 +58,7 @@
 {
 	asm volatile(LOCK_PREFIX "subq %1,%0"
 		     : "=m" (v->counter)
-		     : "er" (i), "m" (v->counter));
+		     : "er" (i), "m" (v->counter) : "memory");
 }
 
 /**

@@ -85,7 +85,7 @@
 {
 	asm volatile(LOCK_PREFIX "incq %0"
 		     : "=m" (v->counter)
-		     : "m" (v->counter));
+		     : "m" (v->counter) : "memory");
 }
 
 /**

@@ -98,7 +98,7 @@
 {
 	asm volatile(LOCK_PREFIX "decq %0"
 		     : "=m" (v->counter)
-		     : "m" (v->counter));
+		     : "m" (v->counter) : "memory");
 }
 
 /**

@@ -116,7 +116,7 @@
 #endif
 
 /* Atomic operations are already serializing on x86 */
-#define smp_mb__before_atomic()	barrier()
-#define smp_mb__after_atomic()	barrier()
+#define smp_mb__before_atomic()	do { } while (0)
+#define smp_mb__after_atomic()	do { } while (0)
 
 #endif /* _ASM_X86_BARRIER_H */

Jari Ruusu  4096R/8132F189 12D6 4C3A DCDA 0AA4 27BD  ACDF F073 3C80 8132 F189

Thanks for these, I'll review them after the next releases happen in a day or so.

thanks,

greg k-h

Well that took a lot longer than expected, sorry, now both queued up.

greg k-h

Compiled and booted on my test system. No dmesg regressions.

thanks,
-- Shuah

Results from Linaro’s test farm.
No regressions on arm64, arm, x86_64, and i386.

Summary
------------------------------------------------------------------------

kernel: 4.9.188-rc1
git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
git branch: linux-4.9.y
git commit: 228fba508ff1bf754e9bc4b3e72a327620ffacf2
git describe: v4.9.187-43-g228fba508ff1
Test details: https://qa-reports.linaro.org/lkft/linux-stable-rc-4.9-oe/build/v4.9.187-43-g228fba508ff1

No regressions (compared to build v4.9.187)

No fixes (compared to build v4.9.187)

Ran 23616 total tests in the following environments and test suites.

Environments
--------------
- dragonboard-410c - arm64
- hi6220-hikey - arm64
- i386
- juno-r2 - arm64
- qemu_arm
- qemu_arm64
- qemu_i386
- qemu_x86_64
- x15 - arm
- x86_64

Test Suites
-----------
* build
* install-android-platform-tools-r2600
* kselftest
* libhugetlbfs
* ltp-cap_bounds-tests
* ltp-commands-tests
* ltp-containers-tests
* ltp-cpuhotplug-tests
* ltp-cve-tests
* ltp-dio-tests
* ltp-fcntl-locktests-tests
* ltp-filecaps-tests
* ltp-fs-tests
* ltp-fs_bind-tests
* ltp-fs_perms_simple-tests
* ltp-fsx-tests
* ltp-hugetlb-tests
* ltp-io-tests
* ltp-ipc-tests
* ltp-math-tests
* ltp-mm-tests
* ltp-nptl-tests
* ltp-pty-tests
* ltp-sched-tests
* ltp-securebits-tests
* ltp-syscalls-tests
* ltp-timers-tests
* perf
* spectre-meltdown-checker-test
* v4l2-compliance
* network-basic-tests
* ltp-open-posix-tests
* prep-tmp-disk
* kvm-unit-tests
* kselftest-vsyscall-mode-native
* kselftest-vsyscall-mode-none

Linaro LKFT
https://lkft.linaro.org

Build results:

	total: 172 pass: 172 fail: 0
Qemu test results:
	total: 333 pass: 333 fail: 0

Guenter

All tests passing for Tegra ...

Test results for stable-v4.9:

    8 builds:	8 pass, 0 fail
    16 boots:	16 pass, 0 fail
    24 tests:	24 pass, 0 fail

Linux version: 4.9.188-rc1-g228fba508ff1
Boards tested: tegra124-jetson-tk1, tegra20-ventana,

                tegra210-p2371-2180, tegra30-cardhu-a04

Cheers
Jon

nvpublic