3.12.9-stable review

This is the start of the stable review cycle for the 3.12.9 release. There are 27 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 Sat Jan 25 19:06:36 UTC 2014. Anything received after that time might be too late.

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

	kernel.org/pub/linux/kernel/v3.0/stable-review/patch-3.12.9-rc1.gz

and the diffstat can be found below.

thanks,

greg k-h

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

Greg Kroah-Hartman <[email protected]>

    Linux 3.12.9-rc1

Taras Kondratiuk <[email protected]>
ARM: 7938/1: OMAP4/highbank: Flush L2 cache before disabling

Ville Syrjälä <[email protected]>
drm/i915: Don't grab crtc mutexes in intel_modeset_gem_init()

Sudeep Holla <[email protected]>
ARM: 7934/1: DT/kernel: fix arch_match_cpu_phys_id to avoid erroneous match

Jon Medhurst <[email protected]>
serial: amba-pl011: use port lock to guard control register access

Geert Uytterhoeven <[email protected]>
mm: Make {,set}page_address() static inline if WANT_PAGE_VIRTUAL

NeilBrown <[email protected]>
md/raid5: Fix possible confusion when multiple write errors occur.

NeilBrown <[email protected]>
md/raid10: fix two bugs in handling of known-bad-blocks.

NeilBrown <[email protected]>
md/raid10: fix bug when raid10 recovery fails to recover a block.

NeilBrown <[email protected]>
md: fix problem when adding device to read-only array with bitmap.

Paulo Zanoni <[email protected]>
drm/i915: fix DDI PLLs HW state readout code

Andreas Rohner <[email protected]>
nilfs2: fix segctor bug that causes file system corruption

Mikulas Patocka <[email protected]>
mm: fix crash when using XFS on loopback

Qais Yousef <[email protected]>
crash_dump: fix compilation error (on MIPS at least)

Steven Rostedt <[email protected]>
ftrace/x86: Load ftrace_ops in parameter not the variable holding it

Hugh Dickins <[email protected]>
thp: fix copy_page_rep GPF by testing is_huge_zero_pmd once only

Steven Rostedt <[email protected]>
SELinux: Fix possible NULL pointer dereference in selinux_inode_permission()

Jan Kara <[email protected]>
writeback: Fix data corruption on NFS

Jean Delvare <[email protected]>
hwmon: (coretemp) Fix truncated name of alarm attributes

Stephen Warren <[email protected]>
i2c: Re-instate body of i2c_parent_is_i2c_adapter()

Eric W. Biederman <[email protected]>
fork: Allow CLONE_PARENT after setns(CLONE_NEWPID)

Eric W. Biederman <[email protected]>
vfs: Fix a regression in mounting proc

Eric W. Biederman <[email protected]>
vfs: In d_path don't call d_dname on a mount point

H Hartley Sweeten <[email protected]>
staging: comedi: adl_pci9111: fix incorrect irq passed to request_irq()

H Hartley Sweeten <[email protected]>
staging: comedi: addi_apci_1032: fix subdevice type/flags bug

Bob Peterson <[email protected]>
GFS2: Increase i_writecount during gfs2_setattr_chown

Robert Richter <[email protected]>
perf/x86/amd/ibs: Fix waking up from S3 for AMD family 10h

Rafael J. Wysocki <[email protected]>
Revert "ACPI: Add BayTrail SoC GPIO and LPSS ACPI IDs"

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

Diffstat:

 Makefile                                        |  4 +-
 arch/arm/kernel/devtree.c                       |  2 +-
 arch/arm/mach-highbank/highbank.c               |  1 +
 arch/arm/mach-omap2/omap4-common.c              |  1 +
 arch/x86/kernel/cpu/perf_event_amd_ibs.c        | 53 +++++++++++++++++++++----
 arch/x86/kernel/entry_32.S                      |  4 +-
 arch/x86/kernel/entry_64.S                      |  2 +-
 drivers/acpi/acpi_lpss.c                        |  1 -
 drivers/gpu/drm/i915/intel_ddi.c                |  8 +++-
 drivers/gpu/drm/i915/intel_display.c            |  4 +-
 drivers/hwmon/coretemp.c                        |  2 +-
 drivers/md/md.c                                 | 18 +++++++--
 drivers/md/md.h                                 |  3 ++
 drivers/md/raid10.c                             | 12 +++---
 drivers/md/raid5.c                              |  4 +-
 drivers/pinctrl/pinctrl-baytrail.c              |  1 -
 drivers/staging/comedi/drivers/addi_apci_1032.c |  4 +-
 drivers/staging/comedi/drivers/adl_pci9111.c    |  2 +-
 drivers/tty/serial/amba-pl011.c                 |  6 +++
 fs/dcache.c                                     |  7 +++-
 fs/fs-writeback.c                               | 15 ++++---
 fs/gfs2/inode.c                                 | 16 +++++++-
 fs/namespace.c                                  |  2 +-
 fs/nilfs2/segment.c                             | 10 +++--
 include/linux/crash_dump.h                      |  2 +
 include/linux/i2c.h                             |  2 +-
 include/linux/mm.h                              | 13 +++---
 kernel/fork.c                                   |  2 +-
 mm/huge_memory.c                                |  6 +--
 mm/util.c                                       |  5 ++-
 security/selinux/hooks.c                        | 20 +++++++++-
 security/selinux/include/objsec.h               |  5 ++-
 32 files changed, 176 insertions(+), 61 deletions(-)

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: "Rafael J. Wysocki" <[email protected]>

commit 2b844ba79f4a114bd228ad6fee040ffd99a0963d upstream.

This reverts commit f6308b36c411 (ACPI: Add BayTrail SoC GPIO and LPSS ACPI IDs), because it causes the Alan Cox' ASUS T100TA to "crash and burn" during boot if the Baytrail pinctrl driver is compiled in.

---
 drivers/acpi/acpi_lpss.c           |    1 -
 drivers/pinctrl/pinctrl-baytrail.c |    1 -
 2 files changed, 2 deletions(-)

@@ -156,7 +156,6 @@ static const struct acpi_device_id acpi_
 	{ "80860F14", (unsigned long)&byt_sdio_dev_desc },
 	{ "80860F41", (unsigned long)&byt_i2c_dev_desc },
 	{ "INT33B2", },
-	{ "INT33FC", },
 
 	{ }
 };

@@ -512,7 +512,6 @@ static const struct dev_pm_ops byt_gpio_
 
 static const struct acpi_device_id byt_gpio_acpi_match[] = {
 	{ "INT33B2", 0 },
-	{ "INT33FC", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, byt_gpio_acpi_match);

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Robert Richter <[email protected]>

commit bee09ed91cacdbffdbcd3b05de8409c77ec9fcd6 upstream.

On AMD family 10h we see following error messages while waking up from S3 for all non-boot CPUs leading to a failed IBS initialization:

Enabling non-boot CPUs ...
smpboot: Booting Node 0 Processor 1 APIC 0x1
[Firmware Bug]: cpu 1, try to use APIC500 (LVT offset 0) for vector 0x400, but the register is already in use for vector 0xf9 on another cpu
perf: IBS APIC setup failed on cpu #1
process: Switch to broadcast mode on CPU1
CPU1 is up
...
ACPI: Waking up from system sleep state S3

Reason for this is that during suspend the LVT offset for the IBS vector gets lost and needs to be reinialized while resuming.

The offset is read from the IBSCTL msr. On family 10h the offset needs to be 1 as offset 0 is used for the MCE threshold interrupt, but firmware assings it for IBS to 0 too. The kernel needs to reprogram the vector. The msr is a readonly node msr, but a new value can be written via pci config space access. The reinitialization is implemented for family 10h in setup_ibs_ctl() which is forced during IBS setup.

This patch fixes IBS setup after waking up from S3 by adding resume/supend hooks for the boot cpu which does the offset reinitialization.

Marking it as stable to let distros pick up this fix.

---
 arch/x86/kernel/cpu/perf_event_amd_ibs.c |   53 ++++++++++++++++++++++++++-----
 1 file changed, 45 insertions(+), 8 deletions(-)

@@ -10,6 +10,7 @@
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/ptrace.h>
+#include <linux/syscore_ops.h>
 
 #include <asm/apic.h>
 

@@ -816,6 +817,18 @@ out:
 	return ret;
 }
 
+static void ibs_eilvt_setup(void)
+{
+	/*
+	 * Force LVT offset assignment for family 10h: The offsets are
+	 * not assigned by the BIOS for this family, so the OS is
+	 * responsible for doing it. If the OS assignment fails, fall
+	 * back to BIOS settings and try to setup this.
+	 */
+	if (boot_cpu_data.x86 == 0x10)
+		force_ibs_eilvt_setup();
+}
+
 static inline int get_ibs_lvt_offset(void)
 {
 	u64 val;

@@ -851,6 +864,36 @@ static void clear_APIC_ibs(void *dummy)
 		setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_FIX, 1);
 }
 
+#ifdef CONFIG_PM
+
+static int perf_ibs_suspend(void)
+{
+	clear_APIC_ibs(NULL);
+	return 0;
+}
+
+static void perf_ibs_resume(void)
+{
+	ibs_eilvt_setup();
+	setup_APIC_ibs(NULL);
+}
+
+static struct syscore_ops perf_ibs_syscore_ops = {
+	.resume		= perf_ibs_resume,
+	.suspend	= perf_ibs_suspend,
+};
+
+static void perf_ibs_pm_init(void)
+{
+	register_syscore_ops(&perf_ibs_syscore_ops);
+}
+
+#else
+
+static inline void perf_ibs_pm_init(void) { }
+
+#endif
+
 static int
 perf_ibs_cpu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)
 {

@@ -877,18 +920,12 @@ static __init int amd_ibs_init(void)
 	if (!caps)
 		return -ENODEV;	/* ibs not supported by the cpu */
 
-	/*
-	 * Force LVT offset assignment for family 10h: The offsets are
-	 * not assigned by the BIOS for this family, so the OS is
-	 * responsible for doing it. If the OS assignment fails, fall
-	 * back to BIOS settings and try to setup this.
-	 */
-	if (boot_cpu_data.x86 == 0x10)
-		force_ibs_eilvt_setup();
+	ibs_eilvt_setup();
 
 	if (!ibs_eilvt_valid())
 		goto out;
 
+	perf_ibs_pm_init();
 	get_online_cpus();
 	ibs_caps = caps;
 	/* make ibs_caps visible to other cpus: */

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Bob Peterson <[email protected]>

commit 62e96cf81988101fe9e086b2877307b6adda5197 upstream.

This patch calls get_write_access in function gfs2_setattr_chown, which merely increases inode->i_writecount for the duration of the function. That will ensure that any file closes won't delete the inode's multi-block reservation while the function is running. It also ensures that a multi-block reservation exists when needed for quota change operations during the chown.

---
 fs/gfs2/inode.c |   16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

@@ -1610,10 +1610,22 @@ static int setattr_chown(struct inode *i
 	if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
 		ogid = ngid = NO_GID_QUOTA_CHANGE;
 
-	error = gfs2_quota_lock(ip, nuid, ngid);
+	error = get_write_access(inode);
 	if (error)
 		return error;
 
+	error = gfs2_rs_alloc(ip);
+	if (error)
+		goto out;
+
+	error = gfs2_rindex_update(sdp);
+	if (error)
+		goto out;
+
+	error = gfs2_quota_lock(ip, nuid, ngid);
+	if (error)
+		goto out;
+
 	if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
 	    !gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
 		error = gfs2_quota_check(ip, nuid, ngid);

@@ -1640,6 +1652,8 @@ out_end_trans:
 	gfs2_trans_end(sdp);
 out_gunlock_q:
 	gfs2_quota_unlock(ip);
+out:
+	put_write_access(inode);
 	return error;
 }
 

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: H Hartley Sweeten <[email protected]>

commit 90daf69a7a3f1d1a41018c799968a0bb896d65e0 upstream.

The SDF_CMD_READ should be one of the s->subdev_flags not part of the s->type.

---
 drivers/staging/comedi/drivers/addi_apci_1032.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -325,8 +325,8 @@ static int apci1032_auto_attach(struct c
 	s = &dev->subdevices[1];
 	if (dev->irq) {
 		dev->read_subdev = s;
-		s->type		= COMEDI_SUBD_DI | SDF_CMD_READ;
-		s->subdev_flags	= SDF_READABLE;
+		s->type		= COMEDI_SUBD_DI;
+		s->subdev_flags	= SDF_READABLE | SDF_CMD_READ;
 		s->n_chan	= 1;
 		s->maxdata	= 1;
 		s->range_table	= &range_digital;

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: H Hartley Sweeten <[email protected]>

commit 48108fe3daa0d142f9b97178fdb23704ea3a407b upstream.

The dev->irq passed to request_irq() will always be 0 when the auto_attach function is called. The pcidev->irq should be used instead to get the correct irq number.

---
 drivers/staging/comedi/drivers/adl_pci9111.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -869,7 +869,7 @@ static int pci9111_auto_attach(struct co
 	pci9111_reset(dev);
 
 	if (pcidev->irq > 0) {
-		ret = request_irq(dev->irq, pci9111_interrupt,
+		ret = request_irq(pcidev->irq, pci9111_interrupt,
 				  IRQF_SHARED, dev->board_name, dev);
 		if (ret)
 			return ret;

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: "Eric W. Biederman" <[email protected]>

commit f48cfddc6729ef133933062320039808bafa6f45 upstream.

The symlink /proc/<pid>/ns/{ipc,mnt,net,pid,user,uts} point to dentries allocated with d_alloc_pseudo that we can mount, and that have interesting names printed out with d_dname.

When these files are bind mounted /proc/mounts is not currently displaying the mount point correctly because d_dname is called instead of just displaying the path where the file is mounted.

Solve this by adding an explicit check to distinguish mounted pseudo inodes and unmounted pseudo inodes. Unmounted pseudo inodes always use mount of their filesstem as the mnt_root in their path making these two cases easy to distinguish.

---
 fs/dcache.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

@@ -3064,8 +3064,13 @@ char *d_path(const struct path *path, ch
 	 * thus don't need to be hashed.  They also don't need a name until a
 	 * user wants to identify the object in /proc/pid/fd/.  The little hack
 	 * below allows us to generate a name for these objects on demand:
+	 *
+	 * Some pseudo inodes are mountable.  When they are mounted
+	 * path->dentry == path->mnt->mnt_root.  In that case don't call d_dname
+	 * and instead have d_path return the mounted path.
 	 */
-	if (path->dentry->d_op && path->dentry->d_op->d_dname)
+	if (path->dentry->d_op && path->dentry->d_op->d_dname &&
+	    (!IS_ROOT(path->dentry) || path->dentry != path->mnt->mnt_root))
 		return path->dentry->d_op->d_dname(path->dentry, buf, buflen);
 
 	rcu_read_lock();

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: "Eric W. Biederman" <[email protected]>

commit 41301ae78a99ead04ea42672a1ab72c6f44cc81d upstream.

Gao feng <[email protected]> reported that commit e51db73532955dc5eaba4235e62b74b460709d5b
userns: Better restrictions on when proc and sysfs can be mounted caused a regression on mounting a new instance of proc in a mount namespace created with user namespace privileges, when binfmt_misc is mounted on /proc/sys/fs/binfmt_misc.

This is an unintended regression caused by the absolutely bogus empty directory check in fs_fully_visible. The check fs_fully_visible replaced didn't even bother to attempt to verify proc was fully visible and hiding proc files with any kind of mount is rare. So for now fix the userspace regression by allowing directory with nlink == 1 as /proc/sys/fs/binfmt_misc has.

I will have a better patch but it is not stable material, or last minute kernel material. So it will have to wait.

---
 fs/namespace.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -2888,7 +2888,7 @@ bool fs_fully_visible(struct file_system
 			struct inode *inode = child->mnt_mountpoint->d_inode;
 			if (!S_ISDIR(inode->i_mode))
 				goto next;
-			if (inode->i_nlink != 2)
+			if (inode->i_nlink > 2)
 				goto next;
 		}
 		visible = true;

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: "Eric W. Biederman" <[email protected]>

commit 1f7f4dde5c945f41a7abc2285be43d918029ecc5 upstream.

The two fundamental things I know we can not allow are:
- A shared signal queue aka CLONE_THREAD. Because we compute the pid and uid of the signal when we place it in the queue.

- Changing the pid and by extention pid_namespace of an existing process.

namespace, to deny CLONE_PARENT, because the parent simply won't know or care.

queues.

User mode threading with CLONE_PARENT|CLONE_VM|CLONE_SIGHAND and tasks in different pid namespaces is almost certainly going to break because it is complicated. But shared signal handlers can look at per thread information to know which pid namespace a process is in, so I don't know of any reason not to support CLONE_PARENT|CLONE_VM|CLONE_SIGHAND threads at the kernel level. It would be absolutely stupid to implement but that is a different thing.

So hmm.

Because it can do no harm, and because it is a regression let's remove the CLONE_PARENT check and send it stable.

---
 kernel/fork.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -1175,7 +1175,7 @@ static struct task_struct *copy_process(
 	 * do not allow it to share a thread group or signal handlers or
 	 * parent with the forking task.
 	 */
-	if (clone_flags & (CLONE_SIGHAND | CLONE_PARENT)) {
+	if (clone_flags & CLONE_SIGHAND) {
 		if ((clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) ||
 		    (task_active_pid_ns(current) !=
 				current->nsproxy->pid_ns_for_children))

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Stephen Warren <[email protected]>

commit 2fac2b891f287691c27ee8d2eeecf39571b27fea upstream.

The body of i2c_parent_is_i2c_adapter() is currently guarded by I2C_MUX. It should be CONFIG_I2C_MUX instead.

Among potentially other problems, this resulted in i2c_lock_adapter() only locking I2C mux child adapters, and not the parent adapter. In turn, this could allow inter-mingling of mux child selection and I2C transactions, which could result in I2C transactions being directed to the wrong I2C bus, and possibly even switching between busses in the middle of a transaction.

One concrete issue caused by this bug was corrupted HDMI EDID reads during boot on the NVIDIA Tegra Seaboard system, although this only became apparent in recent linux-next, when the boot timing was changed just enough to trigger the race condition.

---
 include/linux/i2c.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -447,7 +447,7 @@ static inline void i2c_set_adapdata(stru
 static inline struct i2c_adapter *
 i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
 {
-#if IS_ENABLED(I2C_MUX)
+#if IS_ENABLED(CONFIG_I2C_MUX)
 	struct device *parent = adapter->dev.parent;
 
 	if (parent != NULL && parent->type == &i2c_adapter_type)

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Jean Delvare <[email protected]>

commit 3f9aec7610b39521c7c69d754de7265f6994c194 upstream.

When the core number exceeds 9, the size of the buffer storing the alarm attribute name is insufficient and the attribute name is truncated. This causes libsensors to skip these attributes as the truncated name is not recognized.

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

@@ -52,7 +52,7 @@ MODULE_PARM_DESC(tjmax, "TjMax value in
 
 #define BASE_SYSFS_ATTR_NO	2	/* Sysfs Base attr no for coretemp */
 #define NUM_REAL_CORES		32	/* Number of Real cores per cpu */
-#define CORETEMP_NAME_LENGTH	17	/* String Length of attrs */
+#define CORETEMP_NAME_LENGTH	19	/* String Length of attrs */
 #define MAX_CORE_ATTRS		4	/* Maximum no of basic attrs */
 #define TOTAL_ATTRS		(MAX_CORE_ATTRS + 1)
 #define MAX_CORE_DATA		(NUM_REAL_CORES + BASE_SYSFS_ATTR_NO)

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Jan Kara <[email protected]>

commit f9b0e058cbd04ada76b13afffa7e1df830543c24 upstream.

Commit 4f8ad655dbc8 "writeback: Refactor writeback_single_inode()" added a condition to skip clean inode. However this is wrong in WB_SYNC_ALL mode because there we also want to wait for outstanding writeback on possibly clean inode. This was causing occasional data corruption issues on NFS because it uses sync_inode() to make sure all outstanding writes are flushed to the server before truncating the inode and with sync_inode() returning prematurely file was sometimes extended back by an outstanding write after it was truncated.

So modify the test to also check for pages under writeback in WB_SYNC_ALL mode.

---
 fs/fs-writeback.c |   15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

@@ -510,13 +510,16 @@ writeback_single_inode(struct inode *ino
 	}
 	WARN_ON(inode->i_state & I_SYNC);
 	/*
-	 * Skip inode if it is clean. We don't want to mess with writeback
-	 * lists in this function since flusher thread may be doing for example
-	 * sync in parallel and if we move the inode, it could get skipped. So
-	 * here we make sure inode is on some writeback list and leave it there
-	 * unless we have completely cleaned the inode.
+	 * Skip inode if it is clean and we have no outstanding writeback in
+	 * WB_SYNC_ALL mode. We don't want to mess with writeback lists in this
+	 * function since flusher thread may be doing for example sync in
+	 * parallel and if we move the inode, it could get skipped. So here we
+	 * make sure inode is on some writeback list and leave it there unless
+	 * we have completely cleaned the inode.
 	 */
-	if (!(inode->i_state & I_DIRTY))
+	if (!(inode->i_state & I_DIRTY) &&
+	    (wbc->sync_mode != WB_SYNC_ALL ||
+	     !mapping_tagged(inode->i_mapping, PAGECACHE_TAG_WRITEBACK)))
 		goto out;
 	inode->i_state |= I_SYNC;
 	spin_unlock(&inode->i_lock);

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Steven Rostedt <[email protected]>

commit 3dc91d4338d698ce77832985f9cb183d8eeaf6be upstream.

While running stress tests on adding and deleting ftrace instances I hit this bug:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
  IP: selinux_inode_permission+0x85/0x160
  PGD 63681067 PUD 7ddbe067 PMD 0
  Oops: 0000 [#1] PREEMPT
  CPU: 0 PID: 5634 Comm: ftrace-test-mki Not tainted 3.13.0-rc4-test-00033-gd2a6dde-dirty #20
  Hardware name:                  /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006
  task: ffff880078375800 ti: ffff88007ddb0000 task.ti: ffff88007ddb0000
  RIP: 0010:[<ffffffff812d8bc5>]  [<ffffffff812d8bc5>] selinux_inode_permission+0x85/0x160
  RSP: 0018:ffff88007ddb1c48  EFLAGS: 00010246
  RAX: 0000000000000000 RBX: 0000000000800000 RCX: ffff88006dd43840
  RDX: 0000000000000001 RSI: 0000000000000081 RDI: ffff88006ee46000
  RBP: ffff88007ddb1c88 R08: 0000000000000000 R09: ffff88007ddb1c54
  R10: 6e6576652f6f6f66 R11: 0000000000000003 R12: 0000000000000000
  R13: 0000000000000081 R14: ffff88006ee46000 R15: 0000000000000000
  FS:  00007f217b5b6700(0000) GS:ffffffff81e21000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033^M
  CR2: 0000000000000020 CR3: 000000006a0fe000 CR4: 00000000000007f0
  Call Trace:
    security_inode_permission+0x1c/0x30
    __inode_permission+0x41/0xa0
    inode_permission+0x18/0x50
    link_path_walk+0x66/0x920
    path_openat+0xa6/0x6c0
    do_filp_open+0x43/0xa0
    do_sys_open+0x146/0x240
    SyS_open+0x1e/0x20
    system_call_fastpath+0x16/0x1b
  Code: 84 a1 00 00 00 81 e3 00 20 00 00 89 d8 83 c8 02 40 f6 c6 04 0f 45 d8 40 f6 c6 08 74 71 80 cf 02 49 8b 46 38 4c 8d 4d cc 45 31 c0 <0f> b7 50 20 8b 70 1c 48 8b 41 70 89 d9 8b 78 04 e8 36 cf ff ff
  RIP  selinux_inode_permission+0x85/0x160
  CR2: 0000000000000020

Investigating, I found that the inode->i_security was NULL, and the dereference of it caused the oops.

in selinux_inode_permission():

	isec = inode->i_security;

	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);

Note, the crash came from stressing the deletion and reading of debugfs files. I was not able to recreate this via normal files. But I'm not sure they are safe. It may just be that the race window is much harder to hit.

What seems to have happened (and what I have traced), is the file is being opened at the same time the file or directory is being deleted. As the dentry and inode locks are not held during the path walk, nor is the inodes ref counts being incremented, there is nothing saving these structures from being discarded except for an rcu_read_lock().

The rcu_read_lock() protects against freeing of the inode, but it does not protect freeing of the inode_security_struct. Now if the freeing of the i_security happens with a call_rcu(), and the i_security field of the inode is not changed (it gets freed as the inode gets freed) then there will be no issue here. (Linus Torvalds suggested not setting the field to NULL such that we do not need to check if it is NULL in the permission check).

Note, this is a hack, but it fixes the problem at hand. A real fix is to restructure the destroy_inode() to call all the destructor handlers from the RCU callback. But that is a major job to do, and requires a lot of work. For now, we just band-aid this bug with this fix (it works), and work on a more maintainable solution in the future.

---
 security/selinux/hooks.c          |   20 ++++++++++++++++++--
 security/selinux/include/objsec.h |    5 ++++-
 2 files changed, 22 insertions(+), 3 deletions(-)

@@ -220,6 +220,14 @@ static int inode_alloc_security(struct i
 	return 0;
 }
 
+static void inode_free_rcu(struct rcu_head *head)
+{
+	struct inode_security_struct *isec;
+
+	isec = container_of(head, struct inode_security_struct, rcu);
+	kmem_cache_free(sel_inode_cache, isec);
+}
+
 static void inode_free_security(struct inode *inode)
 {
 	struct inode_security_struct *isec = inode->i_security;

@@ -230,8 +238,16 @@ static void inode_free_security(struct i
 		list_del_init(&isec->list);
 	spin_unlock(&sbsec->isec_lock);
 
-	inode->i_security = NULL;
-	kmem_cache_free(sel_inode_cache, isec);
+	/*
+	 * The inode may still be referenced in a path walk and
+	 * a call to selinux_inode_permission() can be made
+	 * after inode_free_security() is called. Ideally, the VFS
+	 * wouldn't do this, but fixing that is a much harder
+	 * job. For now, simply free the i_security via RCU, and
+	 * leave the current inode->i_security pointer intact.
+	 * The inode will be freed after the RCU grace period too.
+	 */
+	call_rcu(&isec->rcu, inode_free_rcu);
 }
 
 static int file_alloc_security(struct file *file)

@@ -38,7 +38,10 @@ struct task_security_struct {
 
 struct inode_security_struct {
 	struct inode *inode;	/* back pointer to inode object */
-	struct list_head list;	/* list of inode_security_struct */
+	union {
+		struct list_head list;	/* list of inode_security_struct */
+		struct rcu_head rcu;	/* for freeing the inode_security_struct */
+	};
 	u32 task_sid;		/* SID of creating task */
 	u32 sid;		/* SID of this object */
 	u16 sclass;		/* security class of this object */

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Hugh Dickins <[email protected]>

commit eecc1e426d681351a6026a7d3e7d225f38955b6c upstream.

We see General Protection Fault on RSI in copy_page_rep: that RSI is what you get from a NULL struct page pointer.

  RIP: 0010:[<ffffffff81154955>]  [<ffffffff81154955>] copy_page_rep+0x5/0x10
  RSP: 0000:ffff880136e15c00  EFLAGS: 00010286
  RAX: ffff880000000000 RBX: ffff880136e14000 RCX: 0000000000000200
  RDX: 6db6db6db6db6db7 RSI: db73880000000000 RDI: ffff880dd0c00000
  RBP: ffff880136e15c18 R08: 0000000000000200 R09: 000000000005987c
  R10: 000000000005987c R11: 0000000000000200 R12: 0000000000000001
  R13: ffffea00305aa000 R14: 0000000000000000 R15: 0000000000000000
  FS:  00007f195752f700(0000) GS:ffff880c7fc20000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000093010000 CR3: 00000001458e1000 CR4: 00000000000027e0
  Call Trace:
    copy_user_huge_page+0x93/0xab
    do_huge_pmd_wp_page+0x710/0x815
    handle_mm_fault+0x15d8/0x1d70
    __do_page_fault+0x14d/0x840
    do_page_fault+0x2f/0x90
    page_fault+0x22/0x30

do_huge_pmd_wp_page() tests is_huge_zero_pmd(orig_pmd) four times: but since shrink_huge_zero_page() can free the huge_zero_page, and we have no hold of our own on it here (except where the fourth test holds page_table_lock and has checked pmd_same), it's possible for it to answer yes the first time, but no to the second or third test. Change all those last three to tests for NULL page.

(Note: this is not the same issue as trinity's DEBUG_PAGEALLOC BUG in copy_page_rep with RSI: ffff88009c422000, reported by Sasha Levin in https://lkml.org/lkml/2013/3/29/103. I believe that one is due to the source page being split, and a tail page freed, while copy is in progress; and not a problem without DEBUG_PAGEALLOC, since the pmd_same check will prevent a miscopy from being made visible.)

---
 mm/huge_memory.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

@@ -1154,7 +1154,7 @@ alloc:
 		new_page = NULL;
 
 	if (unlikely(!new_page)) {
-		if (is_huge_zero_pmd(orig_pmd)) {
+		if (!page) {
 			ret = do_huge_pmd_wp_zero_page_fallback(mm, vma,
 					address, pmd, orig_pmd, haddr);
 		} else {

@@ -1181,7 +1181,7 @@ alloc:
 
 	count_vm_event(THP_FAULT_ALLOC);
 
-	if (is_huge_zero_pmd(orig_pmd))
+	if (!page)
 		clear_huge_page(new_page, haddr, HPAGE_PMD_NR);
 	else
 		copy_user_huge_page(new_page, page, haddr, vma, HPAGE_PMD_NR);

@@ -1207,7 +1207,7 @@ alloc:
 		page_add_new_anon_rmap(new_page, vma, haddr);
 		set_pmd_at(mm, haddr, pmd, entry);
 		update_mmu_cache_pmd(vma, address, pmd);
-		if (is_huge_zero_pmd(orig_pmd)) {
+		if (!page) {
 			add_mm_counter(mm, MM_ANONPAGES, HPAGE_PMD_NR);
 			put_huge_zero_page();
 		} else {

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Steven Rostedt <[email protected]>

commit 1739f09e33d8f66bf48ddbc3eca615574da6c4f6 upstream.

Function tracing callbacks expect to have the ftrace_ops that registered it passed to them, not the address of the variable that holds the ftrace_ops that registered it.

Use a mov instead of a lea to store the ftrace_ops into the parameter of the function tracing callback.

---
 arch/x86/kernel/entry_32.S |    4 ++--
 arch/x86/kernel/entry_64.S |    2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

@@ -1085,7 +1085,7 @@ ENTRY(ftrace_caller)
 	pushl $0	/* Pass NULL as regs pointer */
 	movl 4*4(%esp), %eax
 	movl 0x4(%ebp), %edx
-	leal function_trace_op, %ecx
+	movl function_trace_op, %ecx
 	subl $MCOUNT_INSN_SIZE, %eax
 
 .globl ftrace_call

@@ -1143,7 +1143,7 @@ ENTRY(ftrace_regs_caller)
 	movl 12*4(%esp), %eax	/* Load ip (1st parameter) */
 	subl $MCOUNT_INSN_SIZE, %eax	/* Adjust ip */
 	movl 0x4(%ebp), %edx	/* Load parent ip (2nd parameter) */
-	leal function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */
+	movl function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */
 	pushl %esp		/* Save pt_regs as 4th parameter */
 
 GLOBAL(ftrace_regs_call)

@@ -88,7 +88,7 @@ END(function_hook)
 	MCOUNT_SAVE_FRAME \skip
 
 	/* Load the ftrace_ops into the 3rd parameter */
-	leaq function_trace_op, %rdx
+	movq function_trace_op(%rip), %rdx
 
 	/* Load ip into the first parameter */
 	movq RIP(%rsp), %rdi

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Qais Yousef <[email protected]>

commit 5a610fcc7390ee60308deaf09426ada87a1eeec2 upstream.

In file included from kernel/crash_dump.c:2:0:
include/linux/crash_dump.h:22:27: error: unknown type name `pgprot_t'

when CONFIG_CRASH_DUMP=y

The error was traced back to commit 9cb218131de1 ("vmcore: introduce remap_oldmem_pfn_range()")

include <asm/pgtable.h> to get the missing definition

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

@@ -6,6 +6,8 @@
 #include <linux/proc_fs.h>
 #include <linux/elf.h>
 
+#include <asm/pgtable.h> /* for pgprot_t */
+
 #define ELFCORE_ADDR_MAX	(-1ULL)
 #define ELFCORE_ADDR_ERR	(-2ULL)
 

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Mikulas Patocka <[email protected]>

commit 03e5ac2fc3bf6f4140db0371e8bb4243b24e3e02 upstream.

Commit 8456a648cf44 ("slab: use struct page for slab management") causes a crash in the LVM2 testsuite on PA-RISC (the crashing test is fsadm.sh). The testsuite doesn't crash on 3.12, crashes on 3.13-rc1 and later.

Bad Address (null pointer deref?): Code=15 regs=000000413edd89a0 (Addr=000006202224647d)

 CPU: 3 PID: 24008 Comm: loop0 Not tainted 3.13.0-rc6 #5
 task: 00000001bf3c0048 ti: 000000413edd8000 task.ti: 000000413edd8000

YZrvWESTHLNXBCVMcbcbcbcbOGFRQPDI
PSW: 00001000000001101111100100001110 Not tainted

 r00-03  000000ff0806f90e 00000000405c8de0 000000004013e6c0 000000413edd83f0
 r04-07  00000000405a95e0 0000000000000200 00000001414735f0 00000001bf349e40
 r08-11  0000000010fe3d10 0000000000000001 00000040829c7778 000000413efd9000
 r12-15  0000000000000000 000000004060d800 0000000010fe3000 0000000010fe3000
 r16-19  000000413edd82a0 00000041078ddbc0 0000000000000010 0000000000000001
 r20-23  0008f3d0d83a8000 0000000000000000 00000040829c7778 0000000000000080
 r24-27  00000001bf349e40 00000001bf349e40 202d66202224640d 00000000405a95e0
 r28-31  202d662022246465 000000413edd88f0 000000413edd89a0 0000000000000001

sr00-03 000000000532c000 0000000000000000 0000000000000000 000000000532c000 sr04-07 0000000000000000 0000000000000000 0000000000000000 0000000000000000

IASQ: 0000000000000000 0000000000000000 IAOQ: 00000000401fe42c 00000000401fe430
IIR: 539c0030 ISR: 00000000202d6000 IOR: 000006202224647d
CPU: 3 CR30: 000000413edd8000 CR31: 0000000000000000
ORIG_R28: 00000000405a95e0
IAOQ[0]: vma_interval_tree_iter_first+0x14/0x48
IAOQ[1]: vma_interval_tree_iter_first+0x18/0x48
RP(r2): flush_dcache_page+0x128/0x388

 Backtrace:
   flush_dcache_page+0x128/0x388
   lo_splice_actor+0x90/0x148 [loop]
   splice_from_pipe_feed+0xc0/0x1d0
   __splice_from_pipe+0xac/0xc0
   lo_direct_splice_actor+0x1c/0x70 [loop]
   splice_direct_to_actor+0xec/0x228
   lo_receive+0xe4/0x298 [loop]
   loop_thread+0x478/0x640 [loop]
   kthread+0x134/0x168
   end_fault_vector+0x20/0x28
   xfs_setsize_buftarg+0x0/0x90 [xfs]

 Kernel panic - not syncing: Bad Address (null pointer deref?)

Commit 8456a648cf44 changes the page structure so that the slab subsystem reuses the page->mapping field.

The crash happens in the following way:
* XFS allocates some memory from slab and issues a bio to read data into it.
* the bio is sent to the loopback device.
* lo_receive creates an actor and calls splice_direct_to_actor.
* lo_splice_actor copies data to the target page.
* lo_splice_actor calls flush_dcache_page because the page may be mapped by userspace. In that case we need to flush the kernel cache.
* flush_dcache_page asks for the list of userspace mappings, however that page->mapping field is reused by the slab subsystem for a different purpose. This causes the crash.

Note that other architectures without coherent caches (sparc, arm, mips) also call page_mapping from flush_dcache_page, so they may crash in the same way.

This patch fixes this bug by testing if the page is a slab page in page_mapping and returning NULL if it is.

The patch also fixes VM_BUG_ON(PageSlab(page)) that could happen in earlier kernels in the same scenario on architectures without cache coherence when CONFIG_DEBUG_VM is enabled - so it should be backported to stable kernels.

In the old kernels, the function page_mapping is placed in include/linux/mm.h, so you should modify the patch accordingly when backporting it.

---
 mm/util.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

@@ -387,7 +387,10 @@ struct address_space *page_mapping(struc
 {
 	struct address_space *mapping = page->mapping;
 
-	VM_BUG_ON(PageSlab(page));
+	/* This happens if someone calls flush_dcache_page on slab page */
+	if (unlikely(PageSlab(page)))
+		return NULL;
+
 	if (unlikely(PageSwapCache(page))) {
 		swp_entry_t entry;
 

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Andreas Rohner <[email protected]>

commit 70f2fe3a26248724d8a5019681a869abdaf3e89a upstream.

There is a bug in the function nilfs_segctor_collect, which results in active data being written to a segment, that is marked as clean. It is possible, that this segment is selected for a later segment construction, whereby the old data is overwritten.

The problem shows itself with the following kernel log message:

nilfs_sufile_do_cancel_free: segment 6533 must be clean

Usually a few hours later the file system gets corrupted:

NILFS: bad btree node (blocknr=8748107): level = 0, flags = 0x0, nchildren = 0 NILFS error (device sdc1): nilfs_bmap_last_key: broken bmap (inode number=114660)

The issue can be reproduced with a file system that is nearly full and with the cleaner running, while some IO intensive task is running. Although it is quite hard to reproduce.

This is what happens:

1. The cleaner starts the segment construction
2. nilfs_segctor_collect is called
3. sc_stage is on NILFS_ST_SUFILE and segments are freed
4. sc_stage is on NILFS_ST_DAT current segment is full
5. nilfs_segctor_extend_segments is called, which allocates a new segment
6. The new segment is one of the segments freed in step 3
7. nilfs_sufile_cancel_freev is called and produces an error message
8. Loop around and the collection starts again
9. sc_stage is on NILFS_ST_SUFILE and segments are freed including the newly allocated segment, which will contain active data and can be allocated at a later time
10. A few hours later another segment construction allocates the segment and causes file system corruption

This can be prevented by simply reordering the statements. If nilfs_sufile_cancel_freev is called before nilfs_segctor_extend_segments the freed segments are marked as dirty and cannot be allocated any more.

---
 fs/nilfs2/segment.c |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

@@ -1440,17 +1440,19 @@ static int nilfs_segctor_collect(struct
 
 		nilfs_clear_logs(&sci->sc_segbufs);
 
-		err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
-		if (unlikely(err))
-			return err;
-
 		if (sci->sc_stage.flags & NILFS_CF_SUFREED) {
 			err = nilfs_sufile_cancel_freev(nilfs->ns_sufile,
 							sci->sc_freesegs,
 							sci->sc_nfreesegs,
 							NULL);
 			WARN_ON(err); /* do not happen */
+			sci->sc_stage.flags &= ~NILFS_CF_SUFREED;
 		}
+
+		err = nilfs_segctor_extend_segments(sci, nilfs, nadd);
+		if (unlikely(err))
+			return err;
+
 		nadd = min_t(int, nadd << 1, SC_MAX_SEGDELTA);
 		sci->sc_stage = prev_stage;
 	}

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Paulo Zanoni <[email protected]>

commit 0882dae983707455e97479e5e904e37673517ebc upstream.

Properly zero the refcounts and crtc->ddi_pll_set so the previous HW state doesn't affect the result of reading the current HW state.

This fixes WARNs about WRPLL refcount if we have an HDMI monitor on HSW and then suspend/resume.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=64379

---
 drivers/gpu/drm/i915/intel_ddi.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

@@ -961,12 +961,18 @@ void intel_ddi_setup_hw_pll_state(struct
 	enum pipe pipe;
 	struct intel_crtc *intel_crtc;
 
+	dev_priv->ddi_plls.spll_refcount = 0;
+	dev_priv->ddi_plls.wrpll1_refcount = 0;
+	dev_priv->ddi_plls.wrpll2_refcount = 0;
+
 	for_each_pipe(pipe) {
 		intel_crtc =
 			to_intel_crtc(dev_priv->pipe_to_crtc_mapping[pipe]);
 
-		if (!intel_crtc->active)
+		if (!intel_crtc->active) {
+			intel_crtc->ddi_pll_sel = PORT_CLK_SEL_NONE;
 			continue;
+		}
 
 		intel_crtc->ddi_pll_sel = intel_ddi_get_crtc_pll(dev_priv,
 								 pipe);

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: NeilBrown <[email protected]>

commit 8313b8e57f55b15e5b7f7fc5d1630bbf686a9a97 upstream.

If an array is started degraded, and then the missing device is found it can be re-added and a minimal bitmap-based recovery will bring it fully up-to-date.

If the array is read-only a recovery would not be allowed. But also if the array is read-only and the missing device was present very recently, then there could be no need for any recovery at all, so we simply include the device in the read-only array without any recovery.

However... if the missing device was removed a little longer ago it could be missing some updates, but if a bitmap is present it will be conditionally accepted pending a bitmap-based update. We don't currently detect this case properly and will include that old device into the read-only array with no recovery even though it really needs a recovery.

This patch keeps track of whether a bitmap-based-recovery is really needed or not in the new Bitmap_sync rdev flag. If that is set, then the device will not be added to a read-only array.

---
 drivers/md/md.c |   18 +++++++++++++++---
 drivers/md/md.h |    3 +++
 2 files changed, 18 insertions(+), 3 deletions(-)

@@ -1119,6 +1119,7 @@ static int super_90_validate(struct mdde
 	rdev->raid_disk = -1;
 	clear_bit(Faulty, &rdev->flags);
 	clear_bit(In_sync, &rdev->flags);
+	clear_bit(Bitmap_sync, &rdev->flags);
 	clear_bit(WriteMostly, &rdev->flags);
 
 	if (mddev->raid_disks == 0) {

@@ -1197,6 +1198,8 @@ static int super_90_validate(struct mdde
 		 */
 		if (ev1 < mddev->bitmap->events_cleared)
 			return 0;
+		if (ev1 < mddev->events)
+			set_bit(Bitmap_sync, &rdev->flags);
 	} else {
 		if (ev1 < mddev->events)
 			/* just a hot-add of a new device, leave raid_disk at -1 */

@@ -1605,6 +1608,7 @@ static int super_1_validate(struct mddev
 	rdev->raid_disk = -1;
 	clear_bit(Faulty, &rdev->flags);
 	clear_bit(In_sync, &rdev->flags);
+	clear_bit(Bitmap_sync, &rdev->flags);
 	clear_bit(WriteMostly, &rdev->flags);
 
 	if (mddev->raid_disks == 0) {

@@ -1687,6 +1691,8 @@ static int super_1_validate(struct mddev
 		 */
 		if (ev1 < mddev->bitmap->events_cleared)
 			return 0;
+		if (ev1 < mddev->events)
+			set_bit(Bitmap_sync, &rdev->flags);
 	} else {
 		if (ev1 < mddev->events)
 			/* just a hot-add of a new device, leave raid_disk at -1 */

@@ -2830,6 +2836,7 @@ slot_store(struct md_rdev *rdev, const c
 		else
 			rdev->saved_raid_disk = -1;
 		clear_bit(In_sync, &rdev->flags);
+		clear_bit(Bitmap_sync, &rdev->flags);
 		err = rdev->mddev->pers->
 			hot_add_disk(rdev->mddev, rdev);
 		if (err) {

@@ -5773,6 +5780,7 @@ static int add_new_disk(struct mddev * m
 			    info->raid_disk < mddev->raid_disks) {
 				rdev->raid_disk = info->raid_disk;
 				set_bit(In_sync, &rdev->flags);
+				clear_bit(Bitmap_sync, &rdev->flags);
 			} else
 				rdev->raid_disk = -1;
 		} else

@@ -7731,7 +7739,8 @@ static int remove_and_add_spares(struct
 		if (test_bit(Faulty, &rdev->flags))
 			continue;
 		if (mddev->ro &&
-		    rdev->saved_raid_disk < 0)
+		    ! (rdev->saved_raid_disk >= 0 &&
+		       !test_bit(Bitmap_sync, &rdev->flags)))
 			continue;
 
 		rdev->recovery_offset = 0;

@@ -7812,9 +7821,12 @@ void md_check_recovery(struct mddev *mdd
 			 * As we only add devices that are already in-sync,
 			 * we can activate the spares immediately.
 			 */
-			clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 			remove_and_add_spares(mddev, NULL);
-			mddev->pers->spare_active(mddev);
+			/* There is no thread, but we need to call
+			 * ->spare_active and clear saved_raid_disk
+			 */
+			md_reap_sync_thread(mddev);
+			clear_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
 			goto unlock;
 		}
 

@@ -129,6 +129,9 @@ struct md_rdev {
 enum flag_bits {
 	Faulty,			/* device is known to have a fault */
 	In_sync,		/* device is in_sync with rest of array */
+	Bitmap_sync,		/* ..actually, not quite In_sync.  Need a
+				 * bitmap-based recovery to get fully in sync
+				 */
 	Unmerged,		/* device is being added to array and should
 				 * be considerred for bvec_merge_fn but not
 				 * yet for actual IO

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: NeilBrown <[email protected]>

commit e8b849158508565e0cd6bc80061124afc5879160 upstream.

commit e875ecea266a543e643b19e44cf472f1412708f9
md/raid10 record bad blocks as needed during recovery.

added code to the "cannot recover this block" path to record a bad block rather than fail the whole recovery.
Unfortunately this new case was placed *after* r10bio was freed rather than *before*, yet it still uses r10bio.
This is will crash with a null dereference.

So move the freeing of r10bio down where it is safe.

URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181

---
 drivers/md/raid10.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

@@ -3220,10 +3220,6 @@ static sector_t sync_request(struct mdde
 			if (j == conf->copies) {
 				/* Cannot recover, so abort the recovery or
 				 * record a bad block */
-				put_buf(r10_bio);
-				if (rb2)
-					atomic_dec(&rb2->remaining);
-				r10_bio = rb2;
 				if (any_working) {
 					/* problem is that there are bad blocks
 					 * on other device(s)

@@ -3255,6 +3251,10 @@ static sector_t sync_request(struct mdde
 					mirror->recovery_disabled
 						= mddev->recovery_disabled;
 				}
+				put_buf(r10_bio);
+				if (rb2)
+					atomic_dec(&rb2->remaining);
+				r10_bio = rb2;
 				break;
 			}
 		}

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: NeilBrown <[email protected]>

commit b50c259e25d9260b9108dc0c2964c26e5ecbe1c1 upstream.

If we discover a bad block when reading we split the request and potentially read some of it from a different device.

The code path of this has two bugs in RAID10.
1/ we get a spin_lock with _irq, but unlock without _irq!! 2/ The calculation of 'sectors_handled' is wrong, as can be clearly
seen by comparison with raid1.c

This leads to at least 2 warnings and a probable crash is a RAID10 ever had known bad blocks.

URL: https://bugzilla.kernel.org/show_bug.cgi?id=68181

---
 drivers/md/raid10.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -1319,7 +1319,7 @@ read_again:
 			/* Could not read all from this device, so we will
 			 * need another r10_bio.
 			 */
-			sectors_handled = (r10_bio->sectors + max_sectors
+			sectors_handled = (r10_bio->sector + max_sectors
 					   - bio->bi_sector);
 			r10_bio->sectors = max_sectors;
 			spin_lock_irq(&conf->device_lock);

@@ -1327,7 +1327,7 @@ read_again:
 				bio->bi_phys_segments = 2;
 			else
 				bio->bi_phys_segments++;
-			spin_unlock(&conf->device_lock);
+			spin_unlock_irq(&conf->device_lock);
 			/* Cannot call generic_make_request directly
 			 * as that will be queued in __generic_make_request
 			 * and subsequent mempool_alloc might block

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: NeilBrown <[email protected]>

commit 1cc03eb93245e63b0b7a7832165efdc52e25b4e6 upstream.

commit 5d8c71f9e5fbdd95650be00294d238e27a363b5c
md: raid5 crash during degradation

Fixed a crash in an overly simplistic way which could leave R5_WriteError or R5_MadeGood set in the stripe cache for devices for which it is no longer relevant.
When those devices are removed and spares added the flags are still set and can cause incorrect behaviour.

commit 14a75d3e07c784c004b4b44b34af996b8e4ac453
md/raid5: preferentially read from replacement device if possible.

Fixed the same bug if a more effective way, so we can now revert the original commit.

---
 drivers/md/raid5.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -3502,7 +3502,7 @@ static void analyse_stripe(struct stripe
 			 */
 			set_bit(R5_Insync, &dev->flags);
 
-		if (rdev && test_bit(R5_WriteError, &dev->flags)) {
+		if (test_bit(R5_WriteError, &dev->flags)) {
 			/* This flag does not apply to '.replacement'
 			 * only to .rdev, so make sure to check that*/
 			struct md_rdev *rdev2 = rcu_dereference(

@@ -3515,7 +3515,7 @@ static void analyse_stripe(struct stripe
 			} else
 				clear_bit(R5_WriteError, &dev->flags);
 		}
-		if (rdev && test_bit(R5_MadeGood, &dev->flags)) {
+		if (test_bit(R5_MadeGood, &dev->flags)) {
 			/* This flag does not apply to '.replacement'
 			 * only to .rdev, so make sure to check that*/
 			struct md_rdev *rdev2 = rcu_dereference(

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Geert Uytterhoeven <[email protected]>

commit f92f455f67fef27929e6043499414605b0c94872 upstream.

{,set}page_address() are macros if WANT_PAGE_VIRTUAL. If !WANT_PAGE_VIRTUAL, they're plain C functions.

If someone calls them with a void *, this pointer is auto-converted to struct page * if !WANT_PAGE_VIRTUAL, but causes a build failure on architectures using WANT_PAGE_VIRTUAL (arc, m68k and sparc64):

drivers/md/bcache/bset.c: In function `__btree_sort':
drivers/md/bcache/bset.c:1190: warning: dereferencing void *' pointer drivers/md/bcache/bset.c:1190: error: request for member virtual' in something not a structure or union

Convert them to static inline functions to fix this. There are already plenty of users of struct page members inside <linux/mm.h>, so there's no reason to keep them as macros.

---
 include/linux/mm.h |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

@@ -762,11 +762,14 @@ static __always_inline void *lowmem_page
 #endif
 
 #if defined(WANT_PAGE_VIRTUAL)
-#define page_address(page) ((page)->virtual)
-#define set_page_address(page, address)			\
-	do {						\
-		(page)->virtual = (address);		\
-	} while(0)
+static inline void *page_address(const struct page *page)
+{
+	return page->virtual;
+}
+static inline void set_page_address(struct page *page, void *address)
+{
+	page->virtual = address;
+}
 #define page_address_init()  do { } while(0)
 #endif
 

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Jon Medhurst <[email protected]>

commit fe43390702a1b5741fdf217063b05c7612b38303 upstream.

When the pl011 is being used for a console, pl011_console_write forces the control register (CR) to enable the UART for transmission and then restores this to the original value afterwards. It does this while holding the port lock.

Unfortunately, when the uart is started or shutdown - say in response to userland using the serial device for a terminal - then this updates the control register without any locking.

This means we can have

  pl011_console_write   Save CR
  pl011_startup         Initialise CR, e.g. enable receive
  pl011_console_write   Restore old CR with receive not enabled

this result is a serial port which doesn't respond to any input.

A similar race in reverse could happen when the device is shutdown.

We can fix these problems by taking the port lock when updating CR.

---
 drivers/tty/serial/amba-pl011.c |    6 ++++++
 1 file changed, 6 insertions(+)

@@ -1537,6 +1537,8 @@ static int pl011_startup(struct uart_por
 	/*
 	 * Provoke TX FIFO interrupt into asserting.
 	 */
+	spin_lock_irq(&uap->port.lock);
+
 	cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
 	writew(cr, uap->port.membase + UART011_CR);
 	writew(0, uap->port.membase + UART011_FBRD);

@@ -1561,6 +1563,8 @@ static int pl011_startup(struct uart_por
 	cr |= UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
 	writew(cr, uap->port.membase + UART011_CR);
 
+	spin_unlock_irq(&uap->port.lock);
+
 	/*
 	 * initialise the old status of the modem signals
 	 */

@@ -1629,11 +1633,13 @@ static void pl011_shutdown(struct uart_p
 	 * it during startup().
 	 */
 	uap->autorts = false;
+	spin_lock_irq(&uap->port.lock);
 	cr = readw(uap->port.membase + UART011_CR);
 	uap->old_cr = cr;
 	cr &= UART011_CR_RTS | UART011_CR_DTR;
 	cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
 	writew(cr, uap->port.membase + UART011_CR);
+	spin_unlock_irq(&uap->port.lock);
 
 	/*
 	 * disable break condition and fifos

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Sudeep Holla <[email protected]>

commit e44ef891e9e68b6ce7d3fd3bac73b7d5433050ae upstream.

The MPIDR contains specific bitfields(MPIDR.Aff{2..0}) which uniquely identify a CPU, in addition to some non-identifying information and reserved bits. The ARM cpu binding defines the 'reg' property to only contain the affinity bits, and any cpu nodes with other bits set in their 'reg' entry are skipped.

As such it is not necessary to mask the phys_id with MPIDR_HWID_BITMASK, and doing so could lead to matching erroneous CPU nodes in the device tree. This patch removes the masking of the physical identifier.

---
 arch/arm/kernel/devtree.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -171,7 +171,7 @@ void __init arm_dt_init_cpu_maps(void)
 
 bool arch_match_cpu_phys_id(int cpu, u64 phys_id)
 {
-	return (phys_id & MPIDR_HWID_BITMASK) == cpu_logical_map(cpu);
+	return phys_id == cpu_logical_map(cpu);
 }
 
 /**

3.12-stable review patch. If anyone has any objections, please let me know.

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

From: Taras Kondratiuk <[email protected]>

commit b25f3e1c358434bf850220e04f28eebfc45eb634 upstream.

Kexec disables outer cache before jumping to reboot code, but it doesn't flush it explicitly. Flush is done implicitly inside of l2x0_disable(). But some SoC's override default .disable handler and don't flush cache. This may lead to a corrupted memory during Kexec reboot on these platforms.

This patch adds cache flush inside of OMAP4 and Highbank outer_cache.disable() handlers to make it consistent with default l2x0_disable().

---
 arch/arm/mach-highbank/highbank.c  |    1 +
 arch/arm/mach-omap2/omap4-common.c |    1 +
 2 files changed, 2 insertions(+)

@@ -66,6 +66,7 @@ void highbank_set_cpu_jump(int cpu, void
 
 static void highbank_l2x0_disable(void)
 {
+	outer_flush_all();
 	/* Disable PL310 L2 Cache controller */
 	highbank_smc1(0x102, 0x0);
 }

@@ -163,6 +163,7 @@ void __iomem *omap4_get_l2cache_base(voi
 
 static void omap4_l2x0_disable(void)
 {
+	outer_flush_all();
 	/* Disable PL310 L2 Cache controller */
 	omap_smc1(0x102, 0x0);
 }

Build test looks good:

	total: 126 pass: 121 skipped: 5 fail: 0

Note that I added several individual build tests for arm but dropped arm:allmodconfig. Background is that arm:allmodconfig is quite notoriously broken nowadays, and it doesn't make much sense to keep testing it.

qemu tests all passed.

Details are available at http://server.roeck-us.net:8010/builders.

Thanks,
Guenter

It's broken? I thought it had been building fine for a while now?

Anyway, thanks for testing, whatever ARM build tests you enable is fine with me.

greg k-h

In mainline, yes. Or at least it was when I dropped it, and I gave up on it.

Guenter

Patch testing - passed
Compile testing - passed
Boot testing - passed
dmesg regression testing - passed - no regressions in emerg, crit, alert, err are clean. No regressions in warn.

-- Shuah

Shuah Khan
Senior Linux Kernel Developer - Open Source Group
Samsung Research America(Silicon Valley)
[email protected] | (970) 672-0658

Hello,

could 3.12.9 and 3.10.28 include
0dce7cd kvm: x86: fix apic_base enable check
? It fixes a regression applied to 3.10.26 and 3.12.7.

Stable was mentioned on kvm-list[1], but it might have been forgotten. More information is in bugzilla[2].

Thanks.

---
1: http://www.spinics.net/lists/kvm/msg99343.html
2: https://bugzilla.redhat.com/show_bug.cgi?id=1055872

I'll queue it up for the next round of stable kernels, thanks.

Yes, no one marked it for the stable tree :(

thanks,

greg k-h

I am also queuing this for the 3.11 kernel. Thanks!

Cheers,
--
Luis

At Thu, 23 Jan 2014 11:06:37 -0800,

I reviewed the following patches and they look good to me.

...

This kernel also passed my test.

- Test Cases:
- Build this kernel.
- Boot this kernel.
- Build the latest mainline kernel with this kernel.

- Test Tool:
https://github.com/satoru-takeuchi/test-linux-stable

- Test Result (kernel .config, ktest config and test log):
http://satoru-takeuchi.org/test-linux-stable/results/<version>-<test datetime>.xz

- Build Environment:
- OS: Debian Jessy x86_64
- CPU: Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz x 4
- memory: 8GB

- Test Target Environment:
- Debian Jessy x86_64 (KVM guest on the Build Environment)
- # of vCPU: 2
- memory: 2GB

Thanks,
Satoru