Re: [PATCH 6.4 0/6] 6.4.3-rc2 review

Re: [PATCH 6.4 0/6] 6.4.3-rc2 review

[Naresh Kamboju]

On Mon, 10 Jul 2023 at 02:15, Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> This is the start of the stable review cycle for the 6.4.3 release.
> There are 6 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 Tue, 11 Jul 2023 20:38:10 +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/v6.x/stable-review/patch-6.4.3-rc2.gz
> or in the git tree and branch at:
>         git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-6.4.y
> and the diffstat can be found below.
>
> thanks,
>
> greg k-h



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

Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>


NOTE:
Following two issues are not specific to this round of review,
We have been noticing on stable-rc 6.4.1-rc1 release with
kselftest merge configs builds testing selftests: net tests.

1)
While running selftests: net: pmtu.sh on arm64 ARM juno-r2, qemu-arm64
and Raspberry Pi 4 Model B following kernel crash reported.

# selftests: net: pmtu.sh
# TEST: ipv4: PMTU exceptions                                         [ OK ]
# TEST: ipv4: PMTU exceptions - nexthop objects                       [ OK ]
# TEST: ipv6: PMTU exceptions                                         [FAIL]
#   PMTU exception wasn't created after exceeding MTU
# TEST: ipv6: PMTU exceptions - nexthop objects                       [FAIL]
#   PMTU exception wasn't created after exceeding MTU
# TEST: ICMPv4 with DSCP and ECN: PMTU exceptions                     [ OK ]
# TEST: ICMPv4 with DSCP and ECN: PMTU exceptions - nexthop objects   [ OK ]
# TEST: UDPv4 with DSCP and ECN: PMTU exceptions                      [ OK ]
# TEST: UDPv4 with DSCP and ECN: PMTU exceptions - nexthop objects    [ OK ]
# TEST: IPv4 over vxlan4: PMTU exceptions                             [ OK ]
# TEST: IPv4 over vxlan4: PMTU exceptions - nexthop objects           [ OK ]
# TEST: IPv6 over vxlan4: PMTU exceptions                             [FAIL]
#   PMTU exception wasn't created after exceeding link layer MTU on
vxlan interface
# TEST: IPv6 over vxlan4: PMTU exceptions - nexthop objects           [FAIL]
#   PMTU exception wasn't created after exceeding link layer MTU on
vxlan interface
# TEST: IPv4 over vxlan6: PMTU exceptions                             [ OK ]
[  226.478625] Unable to handle kernel paging request at virtual
address ffff800974529000
[  226.486721] Mem abort info:
[  226.489534]   ESR = 0x0000000096000005
[  226.493304]   EC = 0x25: DABT (current EL), IL = 32 bits
[  226.498643]   SET = 0, FnV = 0
[  226.501716]   EA = 0, S1PTW = 0
[  226.504876]   FSC = 0x05: level 1 translation fault
[  226.509778] Data abort info:
[  226.512675]   ISV = 0, ISS = 0x00000005
[  226.516531]   CM = 0, WnR = 0
[  226.519518] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000082721000
[  226.526249] [ffff800974529000] pgd=10000009fffff003,
p4d=10000009fffff003, pud=0000000000000000
[  226.535343] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
[  226.541633] Modules linked in: act_csum libcrc32c act_pedit
cls_flower sch_prio bpfilter ip_tables x_tables veth macvtap tap tun
cfg80211 bluetooth rfkill tda998x hdlcd cec drm_dma_helper
onboard_usb_hub drm_kms_helper crct10dif_ce sch_fq_codel fuse drm
[last unloaded: test_blackhole_dev]
[  226.567412] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.3-rc2 #1
[  226.573614] Hardware name: ARM Juno development board (r2) (DT)
[  226.579549] pstate: 000000c5 (nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[  226.586534] pc : percpu_counter_add_batch+0x40/0x148
[  226.591529] lr : percpu_counter_add_batch+0x124/0x148
[  226.596603] sp : ffff800008003dc0
[  226.599926] x29: ffff800008003dc0 x28: ffff80000b282040 x27: ffff800008199b00
[  226.607101] x26: ffff800008199ab4 x25: 0000000000000000 x24: ffff80000b318888
[  226.614275] x23: ffff80000b274b80 x22: 0000000000000020 x21: 0000000000000000
[  226.621449] x20: ffffffffffffffff x19: ffff00082892d740 x18: 0000000000000000
[  226.628623] x17: ffff800974529000 x16: 0000000000000000 x15: 00000000000001da
[  226.635796] x14: 0000000000000400 x13: ffff8009745ce000 x12: 0000000000000000
[  226.642969] x11: ffff80000a7cac24 x10: 0000000000000000 x9 : ffff8000094984cc
[  226.650143] x8 : ffff800008003cd8 x7 : 0000000000000000 x6 : 0000000000000101
[  226.657317] x5 : 0000000000000000 x4 : ffff800008003da0 x3 : 0000000000000000
[  226.664489] x2 : 0000000100000101 x1 : ffff800974529000 x0 : 0000000000000000
[  226.671663] Call trace:
[  226.674116]  percpu_counter_add_batch+0x40/0x148
[  226.678756]  dst_destroy+0x18c/0x240
[  226.682351]  dst_destroy_rcu+0x24/0x40
[  226.686118]  rcu_core+0x464/0xe80
[  226.689453]  rcu_core_si+0x18/0x30
[  226.692872]  __do_softirq+0x130/0x4f4
[  226.696549]  ____do_softirq+0x18/0x30
[  226.700228]  call_on_irq_stack+0x24/0x58
[  226.704167]  do_softirq_own_stack+0x24/0x38
[  226.708367]  __irq_exit_rcu+0x17c/0x1b0
[  226.712220]  irq_exit_rcu+0x18/0x48
[  226.715723]  el1_interrupt+0x38/0x68
[  226.719314]  el1h_64_irq_handler+0x18/0x28
[  226.723426]  el1h_64_irq+0x64/0x68
[  226.726841]  cpuidle_enter_state+0x148/0x5b0
[  226.731129]  cpuidle_enter+0x40/0x60
[  226.734723]  do_idle+0x22c/0x2b8
[  226.737970]  cpu_startup_entry+0x30/0x40
[  226.741912]  rest_init+0x114/0x1c0
[  226.745329]  arch_call_rest_init+0x18/0x20
[  226.749444]  start_kernel+0x5e0/0x6f8
[  226.753121]  __primary_switched+0xbc/0xd0
[  226.757152] Code: 927902b9 36380775 d538d081 f9402e60 (b8616817)
[  226.763268] ---[ end trace 0000000000000000 ]---
[  226.767898] Kernel panic - not syncing: Oops: Fatal exception in interrupt
[  226.774790] SMP: stopping secondary CPUs
[  226.778932] Kernel Offset: disabled
[  226.782428] CPU features: 0x800004,18780800,0000421b
[  226.787408] Memory Limit: none
[  226.790479] ---[ end Kernel panic - not syncing: Oops: Fatal
exception in interrupt ]---


Links:
 - https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-6.4.y/build/v6.4.1-22-g3e37df3ffd9a/testrun/18251735/suite/log-parser-test/test/check-kernel-oops/log
 - https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-6.4.y/build/v6.4.1-22-g3e37df3ffd9a/testrun/18251735/suite/log-parser-test/tests/
 - https://lkft.validation.linaro.org/scheduler/job/6578667#L4613
 - https://storage.tuxsuite.com/public/linaro/lkft/builds/2SLr5Fizk6DFnf66nxHoLw4mw5n/

And

2)
While running selftests: net: vrf-xfrm-tests.sh on arm64 Raspberry Pi 4 Model B
and arm64 Qualcomm Technologies APQ 8016 SBC devices.

# selftests: net: vrf-xfrm-tests.sh

#
# No qdisc on VRF device
# TEST: IPv6 no xfrm policy                                           [ OK ]
# Cannot open netlink socket: Protocol not supported
[ 3310.312970] audit: type=1334 audit(1651171022.511:197): prog-id=59 op=LOAD
# TEST: IPv4 xfrm policy based on address                             [ OK ]
# TEST: IPv6 xfrm policy based on address                             [ OK ]
# Cannot open netlink socket: Protocol not supported
# TEST: IPv6 xfrm policy with VRF in selector                         [ OK ]
# TEST: IPv4 xfrm policy with xfrm device                             [FAIL]
# TEST: IPv6 xfrm policy with xfrm device                             [FAIL]
#
# netem qdisc on VRF device
# Cannot open netlink socket: Protocol not supported
...
[ 3326.099841]
[ 3326.108605] =============================
[ 3326.117159] WARNING: suspicious RCU usage
[ 3326.125672] 6.4.3-rc2 #1 Not tainted
[ 3326.134070] -----------------------------
[ 3326.142459] include/net/neighbour.h:302 suspicious
rcu_dereference_check() usage!
[ 3326.150984]
[ 3326.150984] other info that might help us debug this:
[ 3326.150984]
[ 3326.175738]
[ 3326.175738] rcu_scheduler_active = 2, debug_locks = 1
[ 3326.192048] 2 locks held by ping/19436:
[ 3326.200354]  #0: ffff00000bce3570 (sk_lock-AF_INET){+.+.}-{0:0},
at: raw_sendmsg+0x25c/0xf18
[ 3326.208962]  #1: ffff80000b397b98 (rcu_read_lock_bh){....}-{1:2},
at: vrf_finish_output+0x70/0x8d0
[ 3326.217663]
[ 3326.217663] stack backtrace:
[ 3326.234476] CPU: 1 PID: 19436 Comm: ping Not tainted 6.4.3-rc2 #1
[ 3326.243032] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
[ 3326.251626] Call trace:
[ 3326.260137]  dump_backtrace+0xa0/0x128
[ 3326.268713]  show_stack+0x30/0x48
[ 3326.277235]  dump_stack_lvl+0x90/0xb0
[ 3326.285718]  dump_stack+0x18/0x28
[ 3326.294123]  lockdep_rcu_suspicious+0x16c/0x230
[ 3326.302589]  vrf_finish_output+0x664/0x8d0
[ 3326.311049]  vrf_output+0x104/0x410
[ 3326.319488]  ip_send_skb+0x60/0x128
[ 3326.327928]  ip_push_pending_frames+0x44/0x70
[ 3326.336395]  raw_sendmsg+0x584/0xf18
[ 3326.344815]  inet_sendmsg+0x50/0x88
[ 3326.353251]  __sys_sendto+0xfc/0x198
[ 3326.361650]  __arm64_sys_sendto+0x34/0x50
[ 3326.369890]  invoke_syscall+0x8c/0x120
[ 3326.377899]  el0_svc_common.constprop.0+0x104/0x130
[ 3326.385824]  do_el0_svc+0x44/0xb8
[ 3326.393644]  el0_svc+0x40/0xa8
[ 3326.401277]  el0t_64_sync_handler+0xbc/0x138
[ 3326.408721]  el0t_64_sync+0x190/0x198
[ 3326.416111]
[ 3326.423395] =============================
[ 3326.430605] WARNING: suspicious RCU usage
[ 3326.437613] 6.4.3-rc2 #1 Not tainted
[ 3326.444481] -----------------------------
[ 3326.451275] include/net/neighbour.h:307 suspicious
rcu_dereference_check() usage!
[ 3326.458148]
[ 3326.458148] other info that might help us debug this:
[ 3326.458148]
[ 3326.477416]
[ 3326.477416] rcu_scheduler_active = 2, debug_locks = 1
[ 3326.489637] 2 locks held by ping/19436:
[ 3326.495704]  #0: ffff00000bce3570 (sk_lock-AF_INET){+.+.}-{0:0},
at: raw_sendmsg+0x25c/0xf18
[ 3326.501817]  #1: ffff80000b397b98 (rcu_read_lock_bh){....}-{1:2},
at: vrf_finish_output+0x70/0x8d0
[ 3326.509274]
[ 3326.509274] stack backtrace:
[ 3326.523226] CPU: 1 PID: 19436 Comm: ping Not tainted 6.4.3-rc2 #1
[ 3326.528565] Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
[ 3326.533774] Call trace:
[ 3326.540093]  dump_backtrace+0xa0/0x128
[ 3326.545130]  show_stack+0x30/0x48
[ 3326.550107]  dump_stack_lvl+0x90/0xb0
[ 3326.554925]  dump_stack+0x18/0x28
[ 3326.559493]  lockdep_rcu_suspicious+0x16c/0x230
[ 3326.563974]  vrf_finish_output+0x618/0x8d0
[ 3326.568383]  vrf_output+0x104/0x410
[ 3326.572598]  ip_send_skb+0x60/0x128
[ 3326.576589]  ip_push_pending_frames+0x44/0x70
[ 3326.580477]  raw_sendmsg+0x584/0xf18
[ 3326.584239]  inet_sendmsg+0x50/0x88
[ 3326.587983]  __sys_sendto+0xfc/0x198
[ 3326.591723]  __arm64_sys_sendto+0x34/0x50
[ 3326.595464]  invoke_syscall+0x8c/0x120
[ 3326.599199]  el0_svc_common.constprop.0+0x104/0x130
[ 3326.602929]  do_el0_svc+0x44/0xb8
[ 3326.606753]  el0_svc+0x40/0xa8
[ 3326.610378]  el0t_64_sync_handler+0xbc/0x138
[ 3326.614029]  el0t_64_sync+0x190/0x198
# TEST: IPv4 no xfrm policy                                           [ OK ]

Links:
 - https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-6.4.y/build/v6.4.1-22-g3e37df3ffd9a/testrun/18251800/suite/log-parser-test/test/check-kernel-warning/log
 - https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-6.4.y/build/v6.4.1-22-g3e37df3ffd9a/testrun/18251800/suite/log-parser-test/tests/
 - https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-6.4.y/build/v6.4.1-22-g3e37df3ffd9a/testrun/18251384/suite/log-parser-test/tests/


 metadata:
  git_ref: linux-6.4.y
  git_repo: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
  git_sha: 3e37df3ffd9a648c9f88f6bbca158e43d5077bef
  git_describe: v6.4.1-22-g3e37df3ffd9a
  kernel_version: 6.4.3-rc2
  kernel-config:
    https://storage.tuxsuite.com/public/linaro/lkft/builds/2SLr5Fizk6DFnf66nxHoLw4mw5n/config
  artifact-location:
    https://storage.tuxsuite.com/public/linaro/lkft/builds/2SLr5Fizk6DFnf66nxHoLw4mw5n/
  toolchain: gcc-11


## Build
* kernel: 6.4.3-rc2
* git: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
* git branch: linux-6.4.y
* git commit: 3e37df3ffd9a648c9f88f6bbca158e43d5077bef
* git describe: v6.4.1-22-g3e37df3ffd9a
* test details:
https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-6.4.y/build/v6.4.1-22-g3e37df3ffd9a

## Test Regressions (compared to v6.4.1)

## Metric Regressions (compared to v6.4.1)

## Test Fixes (compared to v6.4.1)

## Metric Fixes (compared to v6.4.1)

## Test result summary
total: 173253, pass: 148435, fail: 2272, skip: 22546, xfail: 0

## Build Summary
* arc: 5 total, 5 passed, 0 failed
* arm: 145 total, 145 passed, 0 failed
* arm64: 54 total, 53 passed, 1 failed
* i386: 41 total, 41 passed, 0 failed
* mips: 30 total, 28 passed, 2 failed
* parisc: 4 total, 4 passed, 0 failed
* powerpc: 38 total, 36 passed, 2 failed
* riscv: 26 total, 25 passed, 1 failed
* s390: 16 total, 14 passed, 2 failed
* sh: 14 total, 12 passed, 2 failed
* sparc: 8 total, 8 passed, 0 failed
* x86_64: 46 total, 46 passed, 0 failed

## Test suites summary
* boot
* fwts
* kselftest-android
* kselftest-arm64
* kselftest-breakpoints
* kselftest-capabilities
* kselftest-cgroup
* kselftest-clone3
* kselftest-core
* kselftest-cpu-hotplug
* kselftest-cpufreq
* kselftest-drivers-dma-buf
* kselftest-efivarfs
* kselftest-exec
* kselftest-filesystems
* kselftest-filesystems-binderfs
* kselftest-firmware
* kselftest-fpu
* kselftest-ftrace
* kselftest-futex
* kselftest-gpio
* kselftest-intel_pstate
* kselftest-ipc
* kselftest-ir
* kselftest-kcmp
* kselftest-kexec
* kselftest-kvm
* kselftest-lib
* kselftest-livepatch
* kselftest-membarrier
* kselftest-memfd
* kselftest-memory-hotplug
* kselftest-mincore
* kselftest-mount
* kselftest-mqueue
* kselftest-net
* kselftest-net-forwarding
* kselftest-net-mptcp
* kselftest-netfilter
* kselftest-nsfs
* kselftest-openat2
* kselftest-pid_namespace
* kselftest-pidfd
* kselftest-proc
* kselftest-pstore
* kselftest-ptrace
* kselftest-rseq
* kselftest-rtc
* kselftest-seccomp
* kselftest-sigaltstack
* kselftest-size
* kselftest-splice
* kselftest-static_keys
* kselftest-sync
* kselftest-sysctl
* kselftest-tc-testing
* kselftest-timens
* kselftest-timers
* kselftest-tmpfs
* kselftest-tpm2
* kselftest-user
* kselftest-user_events
* kselftest-vDSO
* kselftest-watchdog
* kselftest-x86
* kselftest-zram
* kunit
* kvm-unit-tests
* libgpiod
* libhugetlbfs
* log-parser-boot
* log-parser-test
* ltp-cap_bounds
* ltp-commands
* ltp-containers
* ltp-controllers
* ltp-cpuhotplug
* ltp-crypto
* ltp-cve
* ltp-dio
* ltp-fcntl-locktests
* ltp-filecaps
* ltp-fs
* ltp-fs_bind
* ltp-fs_perms_simple
* ltp-fsx
* ltp-hugetlb
* ltp-io
* ltp-ipc
* ltp-math
* ltp-mm
* ltp-nptl
* ltp-pty
* ltp-sched
* ltp-securebits
* ltp-smoke
* ltp-syscalls
* ltp-tracing
* network-basic-tests
* perf
* rcutorture
* v4l2-compliance
* vdso

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

Re: [PATCH 6.4 0/6] 6.4.3-rc2 review

[Jakub Kicinski]

On Mon, 10 Jul 2023 17:11:18 +0530 Naresh Kamboju wrote:
>   git_repo: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
>   git_sha: 3e37df3ffd9a648c9f88f6bbca158e43d5077bef

I can't find this sha :( Please report back if you can still repro this
and how we get get the relevant code

Re: [PATCH 6.4 0/6] 6.4.3-rc2 review

[Pavel Machek]

[-- Attachment #1: Type: text/plain, Size: 636 bytes --]

Hi!

> >   git_repo: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
> >   git_sha: 3e37df3ffd9a648c9f88f6bbca158e43d5077bef
> 
> I can't find this sha :( Please report back if you can still repro this
> and how we get get the relevant code

That sha seems to be:

commit 3e37df3ffd9a648c9f88f6bbca158e43d5077bef
Author: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date:   Sun Jul 9 22:38:22 2023 +0200

    Linux 6.4.3-rc2

Best regards,
								Pavel
-- 
DENX Software Engineering GmbH,        Managing Director: Erika Unter
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 195 bytes --]

Re: [PATCH 6.4 0/6] 6.4.3-rc2 review

[Naresh Kamboju]

On Wed, 12 Jul 2023 at 14:01, Pavel Machek <pavel@denx.de> wrote:
>
> Hi!
>
> > >   git_repo: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
> > >   git_sha: 3e37df3ffd9a648c9f88f6bbca158e43d5077bef
> >
> > I can't find this sha :( Please report back if you can still repro this
> > and how we get get the relevant code
>
> That sha seems to be:
>
> commit 3e37df3ffd9a648c9f88f6bbca158e43d5077bef
> Author: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Date:   Sun Jul 9 22:38:22 2023 +0200
>
>     Linux 6.4.3-rc2

That is the commit id from stable-rc tree.

I have re-tested the reported issues multiple times and
it seems that it is intermittently reproducible.
Following list of links shows kernel crashes while testing
selftest net pmtu.sh

1)
Unable to handle kernel paging request at virtual address
https://lkft.validation.linaro.org/scheduler/job/6579624#L4648


2)
include/net/neighbour.h:302 suspicious rcu_dereference_check() usage!

https://lkft.validation.linaro.org/scheduler/job/6579625#L7500
https://lkft.validation.linaro.org/scheduler/job/6579626#L7509
https://lkft.validation.linaro.org/scheduler/job/6579622#L7537
https://lkft.validation.linaro.org/scheduler/job/6579623#L7469

- Naresh

Re: [PATCH 6.4 0/6] 6.4.3-rc2 review

[Jakub Kicinski]

On Wed, 12 Jul 2023 18:41:46 +0530 Naresh Kamboju wrote:
> That is the commit id from stable-rc tree.
> 
> I have re-tested the reported issues multiple times and
> it seems that it is intermittently reproducible.
> Following list of links shows kernel crashes while testing
> selftest net pmtu.sh
> 
> 1)
> Unable to handle kernel paging request at virtual address
> https://lkft.validation.linaro.org/scheduler/job/6579624#L4648
> 
> 
> 2)
> include/net/neighbour.h:302 suspicious rcu_dereference_check() usage!
> 
> https://lkft.validation.linaro.org/scheduler/job/6579625#L7500
> https://lkft.validation.linaro.org/scheduler/job/6579626#L7509
> https://lkft.validation.linaro.org/scheduler/job/6579622#L7537
> https://lkft.validation.linaro.org/scheduler/job/6579623#L7469

Nothing jumps out at me.

David, any ideas?

Re: [PATCH 6.4 0/6] 6.4.3-rc2 review

[David Ahern]

On 7/12/23 12:02 PM, Jakub Kicinski wrote:
> On Wed, 12 Jul 2023 18:41:46 +0530 Naresh Kamboju wrote:
>> That is the commit id from stable-rc tree.
>>
>> I have re-tested the reported issues multiple times and
>> it seems that it is intermittently reproducible.
>> Following list of links shows kernel crashes while testing
>> selftest net pmtu.sh
>>
>> 1)
>> Unable to handle kernel paging request at virtual address
>> https://lkft.validation.linaro.org/scheduler/job/6579624#L4648
>>
>>
>> 2)
>> include/net/neighbour.h:302 suspicious rcu_dereference_check() usage!
>>
>> https://lkft.validation.linaro.org/scheduler/job/6579625#L7500
>> https://lkft.validation.linaro.org/scheduler/job/6579626#L7509
>> https://lkft.validation.linaro.org/scheduler/job/6579622#L7537
>> https://lkft.validation.linaro.org/scheduler/job/6579623#L7469
> 
> Nothing jumps out at me.
> 
> David, any ideas?

No. Since it is a selftest in the linux repo, any chance for a git
bisect based on that one test?