4.4.275-rc1 review

This is the start of the stable review cycle for the 4.4.275 release. There are 4 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 Sun, 11 Jul 2021 13:14:09 +0000. 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-4.4.275-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-4.4.y
and the diffstat can be found below.

thanks,

greg k-h

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

Greg Kroah-Hartman <[email protected]>

    Linux 4.4.275-rc1

Masami Hiramatsu <[email protected]>
arm: kprobes: Allow to handle reentered kprobe on single-stepping

Juergen Gross <[email protected]>
xen/events: reset active flag for lateeoi events later

Christian König <[email protected]>
drm/nouveau: fix dma_address check for CPU/GPU sync

ManYi Li <[email protected]>
scsi: sr: Return appropriate error code when disk is ejected

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

Diffstat:

 Makefile                             |  4 ++--
 arch/arm/probes/kprobes/core.c       |  6 ++++++
 drivers/gpu/drm/nouveau/nouveau_bo.c |  4 ++--
 drivers/scsi/sr.c                    |  2 ++
 drivers/xen/events/events_base.c     | 23 +++++++++++++++++++----
 5 files changed, 31 insertions(+), 8 deletions(-)

From: ManYi Li <[email protected]>

[ Upstream commit 7dd753ca59d6c8cc09aa1ed24f7657524803c7f3 ]

Handle a reported media event code of 3. This indicates that the media has been removed from the drive and user intervention is required to proceed. Return DISK_EVENT_EJECT_REQUEST in that case.

---
 drivers/scsi/sr.c | 2 ++
 1 file changed, 2 insertions(+)

index 7dd4d9ded249..6e31cedf0b6c 100644
@@ -216,6 +216,8 @@ static unsigned int sr_get_events(struct scsi_device *sdev)
 		return DISK_EVENT_EJECT_REQUEST;
 	else if (med->media_event_code == 2)
 		return DISK_EVENT_MEDIA_CHANGE;
+	else if (med->media_event_code == 3)
+		return DISK_EVENT_EJECT_REQUEST;
 	return 0;
 }
 

2.30.2

From: Christian König <[email protected]>

[ Upstream commit d330099115597bbc238d6758a4930e72b49ea9ba ]

AGP for example doesn't have a dma_address array.

---
 drivers/gpu/drm/nouveau/nouveau_bo.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

index 78f520d05de9..58c310930bf2 100644
@@ -458,7 +458,7 @@ nouveau_bo_sync_for_device(struct nouveau_bo *nvbo)
 	struct ttm_dma_tt *ttm_dma = (struct ttm_dma_tt *)nvbo->bo.ttm;
 	int i;
 
-	if (!ttm_dma)
+	if (!ttm_dma || !ttm_dma->dma_address)
 		return;
 
 	/* Don't waste time looping if the object is coherent */

@@ -478,7 +478,7 @@ nouveau_bo_sync_for_cpu(struct nouveau_bo *nvbo)
 	struct ttm_dma_tt *ttm_dma = (struct ttm_dma_tt *)nvbo->bo.ttm;
 	int i;
 
-	if (!ttm_dma)
+	if (!ttm_dma || !ttm_dma->dma_address)
 		return;
 
 	/* Don't waste time looping if the object is coherent */

2.30.2

From: Juergen Gross <[email protected]>

commit 3de218ff39b9e3f0d453fe3154f12a174de44b25 upstream.

In order to avoid a race condition for user events when changing cpu affinity reset the active flag only when EOI-ing the event.

This is working fine as all user events are lateeoi events. Note that lateeoi_ack_mask_dynirq() is not modified as there is no explicit call to xen_irq_lateeoi() expected later.

---
 drivers/xen/events/events_base.c |   23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

@@ -533,6 +533,9 @@ static void xen_irq_lateeoi_locked(struc
 	}
 
 	info->eoi_time = 0;
+
+	/* is_active hasn't been reset yet, do it now. */
+	smp_store_release(&info->is_active, 0);
 	do_unmask(info, EVT_MASK_REASON_EOI_PENDING);
 }
 

@@ -1777,10 +1780,22 @@ static void lateeoi_ack_dynirq(struct ir
 	struct irq_info *info = info_for_irq(data->irq);
 	evtchn_port_t evtchn = info ? info->evtchn : 0;
 
-	if (VALID_EVTCHN(evtchn)) {
-		do_mask(info, EVT_MASK_REASON_EOI_PENDING);
-		ack_dynirq(data);
-	}
+	if (!VALID_EVTCHN(evtchn))
+		return;
+
+	do_mask(info, EVT_MASK_REASON_EOI_PENDING);
+
+	if (unlikely(irqd_is_setaffinity_pending(data)) &&
+	    likely(!irqd_irq_disabled(data))) {
+		do_mask(info, EVT_MASK_REASON_TEMPORARY);
+
+		clear_evtchn(evtchn);
+
+		irq_move_masked_irq(data);
+
+		do_unmask(info, EVT_MASK_REASON_TEMPORARY);
+	} else
+		clear_evtchn(evtchn);
 }
 
 static void lateeoi_mask_ack_dynirq(struct irq_data *data)

From: Masami Hiramatsu <[email protected]>

commit f3fbd7ec62dec1528fb8044034e2885f2b257941 upstream.

This is arm port of commit 6a5022a56ac3 ("kprobes/x86: Allow to handle reentered kprobe on single-stepping")

Since the FIQ handlers can interrupt in the single stepping (or preparing the single stepping, do_debug etc.), we should consider a kprobe is hit in the NMI handler. Even in that case, the kprobe is allowed to be reentered as same as the kprobes hit in kprobe handlers
(KPROBE_HIT_ACTIVE or KPROBE_HIT_SSDONE).

The real issue will happen when a kprobe hit while another reentered kprobe is processing (KPROBE_REENTER), because we already consumed a saved-area for the previous kprobe.

---
 arch/arm/probes/kprobes/core.c |    6 ++++++
 1 file changed, 6 insertions(+)

@@ -270,6 +270,7 @@ void __kprobes kprobe_handler(struct pt_
 			switch (kcb->kprobe_status) {
 			case KPROBE_HIT_ACTIVE:
 			case KPROBE_HIT_SSDONE:
+			case KPROBE_HIT_SS:
 				/* A pre- or post-handler probe got us here. */
 				kprobes_inc_nmissed_count(p);
 				save_previous_kprobe(kcb);

@@ -278,6 +279,11 @@ void __kprobes kprobe_handler(struct pt_
 				singlestep(p, regs, kcb);
 				restore_previous_kprobe(kcb);
 				break;
+			case KPROBE_REENTER:
+				/* A nested probe was hit in FIQ, it is a BUG */
+				pr_warn("Unrecoverable kprobe detected at %p.\n",
+					p->addr);
+				/* fall through */
 			default:
 				/* impossible cases */
 				BUG();

Hi!

CIP testing did not find any problems here:

https://gitlab.com/cip-project/cip-testing/linux-stable-rc-ci/-/tree/linux-4.4.y

Best regards,
Pavel

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

All tests passing for Tegra ...

Test results for stable-v4.4:

    6 builds:	6 pass, 0 fail
    12 boots:	12 pass, 0 fail
    30 tests:	30 pass, 0 fail

Linux version: 4.4.275-rc1-gaaf5d64b8bc0
Boards tested: tegra124-jetson-tk1, tegra20-ventana,

                tegra30-cardhu-a04

Jon

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

thanks,
-- Shuah

Build results:

	total: 160 pass: 160 fail: 0
Qemu test results:
	total: 326 pass: 326 fail: 0

Guenter

Results from Linaro’s test farm.
Regressions on arm64 noticed.

GOOD: v4.4.273
BAD: v4.4.274

Regressions found on arm64 juno-r2 and qemu_arm64 device. ltp-containers-tests failed:
- netns_comm_ip_ipv6_ioctl
- netns_comm_ns_exec_ipv6_ioctl
- netns_comm_ip_ipv6_netlink
- netns_breakns_ns_exec_ipv6_netlink
- netns_breakns_ns_exec_ipv4_ioctl
- netns_netlink
- netns_comm_ip_ipv4_netlink
- netns_breakns_ns_exec_ipv4_netlink
- netns_breakns_ip_ipv6_netlink
- netns_breakns_ip_ipv4_ioctl
- netns_comm_ns_exec_ipv4_netlink
- netns_comm_ip_ipv4_ioctl
- netns_comm_ns_exec_ipv4_ioctl
- netns_comm_ns_exec_ipv6_netlink
- netns_breakns_ip_ipv6_ioctl
- netns_breakns_ip_ipv4_netlink
- netns_breakns_ns_exec_ipv6_ioctl

Test output log:
-----------------
module tun: overflow in relocation type 261 val fffffdfffc000654
open: No such device
netns_netlink.c:103: TBROK: adding interface failed

netns_breakns 1 TINFO: timeout per run is 0h 15m 0s module veth: overflow in relocation type 261 val fffffdfffc040000 module veth: overflow in relocation type 261 val fffffdfffc080000 RTNETLINK answers: Operation not supported netns_breakns 1 TBROK: unable to create veth pair devices Cannot find device \"veth0\"

step to reproduce:
-------------------------

 # boot qemu arm64 and run ltp netns_netlink test.

- cd /opt/ltp
- ./runltp -s netns_netlink

We have started the git bisection script to find the first bad commit causing these LTP netns test failures.

--
Linaro LKFT
https://lkft.linaro.org