[Kernel-packages] [Bug 1987287] Comment bridged from LTC Bugzilla
--- Comment From niklas.schne...@ibm.com 2022-11-14 10:41 EDT---
*** Bug 200496 has been marked as a duplicate of this bug. ***
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https://bugs.launchpad.net/bugs/1987287
Title:
[UBUNTU 20.04] mlx5 driver crashes on accessing device attributes
during recovery
Status in Ubuntu on IBM z Systems:
Fix Released
Status in linux package in Ubuntu:
Invalid
Status in linux source package in Focal:
Fix Released
Bug description:
SRU Justification:
--
[Impact]
* If the mlx5 driver is reloading while the recovery flow is happening,
and if it receives new commands before the command interface is up
again, this can lead to null pointer that tries to access non-
initialized command structures.
* So it's required to avoid processing commands before the command
interface is up again.
* This is accomplished by a new cmdif state that helps to avoid
processing commands while cmdif is not ready.
[Fix]
* backport of f7936ddd35d8 f7936ddd35d8b849daf0372770c7c9dbe7910fca
"net/mlx5: Avoid processing commands before cmdif is ready"
[Test Plan]
* An Ubuntu Server for s390x 18.04 or 20.04 LPAR or z/VM installation
is needed that has Mellanox cards (RoCE Express 2.1) assigned,
configured and enabled and that runs a 5.4 kernel (on bionic hwe-5.4).
* Now trigger a recovery (guess that can be done at the Support Element)
and reload the driver at the same time.
* Make sure the module/driver mlx5 is loaded and in use
(otherwise it can't be removed/unloaded).
* Now remove/unload the module with:
sudo modprobe -r mlx5
and (re-)load it again with:
sudo modprobe mlx5
* Due to the lack of RoCE Express 2.1 hardware,
IBM needs to do the verification.
[Where problems could occur]
* In case there is an issue with 'cmdif' it might not have the correct
interface state, which:
- either might lead to the fact that commands are not properly blocked
and the situation is similar like before
- or the commands may get always blocked,
which render the hardware useless
- or might block in wrong situation,
which will cause unexpected issues and broken behavior.
* Since the patch got upstream accepted with v5.7-rc7 it's
not new to the kernel, was already part of groovy (and above)
and is therefor already in use by newer Ubuntu releases.
[Other Info]
* Since the patch is upstream since v5.7-rc7,
it's already included in jammy and kinetic.
* Since the upstream patch incl. the line:
Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox
Connect-IB adapters") it looks to me that it was forgotten
to mark the patch for upstream stable updates.
* Such SRUs for focal's 5.4 will automatically land in bionic's
hwe-5.4, too. But since this was especially requested for
bionic's hwe-5.4, I wanted to mention this here.
__
We recently got a bug report for systems running Ubuntu 20.04 that were
crashing with backtraces pointing at the mlx5 driver's handling of
mlx5_ethtool_get_link_ksettings()
when this is called through the sysfs (going through ethtool might have
different checks).
I managed to find a reliable way to reproduce the issue that I believe isn't
tied to IBM Z at all.
The procedure to reproduce is as follows. I created a script to read
the sysfs attributes for the link's speed and duplex mode in a loop:
#!/usr/bin/env bash
if [ $# -lt 1 ]; then
echo "Usage: $0 "
exit 1
fi
while true; do
cat /sys/class/net/$1/duplex > /dev/null
cat /sys/class/net/$1/speed > /dev/null
done
Executed with:
# ./script.sh enP10p0s0
I ran this in one bash session and then in another one I triggered a PCI
reset with
the follwoing command where one needs to replace with the PCI address
of the NIC:
echo 1 > /sys/bus/pci/devices//reset
Then first I got a lot of the following messages:
mlx5_core 0010:00:00.0 enP16p0s0: mlx5e_ethtool_get_link_ksettings:
query port ptys failed: -5
And then as the mlx5 driver's recovery kicks in the oops as below:
[ 659.103947] mlx5_core 0010:00:00.0: wait vital counter value 0x7b399f
after 1 iterations
[ 659.103947] mlx5_core 0010:00:00.0: mlx5_pci_resume was called
[ 659.103966] mlx5_core 0010:00:00.0: firmware version: 14.32.1010
[ 659.104169] Unable to handle kernel pointer dereference in virtual kernel
address space
[ 659.104171] Failing address: TEID: 0483
[ 659.104172] Fault in home space mode while using kernel ASCE.
[ 659.104173] AS:3d29c007 R3:fffd0007 S:fffd5800
P:003d
[ 659.104200] Oops: 0004 ilc:2 [#1] SMP
[ 659.104202] Modules linked in: s390_trng ism smc pnet chsc_sch eadm_sch
[Kernel-packages] [Bug 1987287] Comment bridged from LTC Bugzilla
--- Comment From niklas.schne...@ibm.com 2022-09-26 05:58 EDT---
(In reply to comment #23)
> Thx for testing!
> The further process is already in place and on a high level (just dates)
> described here:
> https://kernel.ubuntu.com/
> So this fix is now incl. in the kernel SRU cycle "2022.09.19".
> Means the updated kernel that incl. the fix will soon (ideally today) land
> in the '-proposed' pocket of the archive (and will be installable by
> everyone who has '-proposed' enabled.
> And if no significant issues arise during the "Bug verification & Regression
> testing" phase, it will be released on '10-Oct'.
> That is the currently plan (however, highly severe and critical fixes and
> CVE have the power to overrule this planned schedule, but this fortunately
> does not happen very often).
I confirmed this works as expected now on 5.4.0-128-generic from
proposed.
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https://bugs.launchpad.net/bugs/1987287
Title:
[UBUNTU 20.04] mlx5 driver crashes on accessing device attributes
during recovery
Status in Ubuntu on IBM z Systems:
Fix Committed
Status in linux package in Ubuntu:
Invalid
Status in linux source package in Focal:
Fix Committed
Bug description:
SRU Justification:
--
[Impact]
* If the mlx5 driver is reloading while the recovery flow is happening,
and if it receives new commands before the command interface is up
again, this can lead to null pointer that tries to access non-
initialized command structures.
* So it's required to avoid processing commands before the command
interface is up again.
* This is accomplished by a new cmdif state that helps to avoid
processing commands while cmdif is not ready.
[Fix]
* backport of f7936ddd35d8 f7936ddd35d8b849daf0372770c7c9dbe7910fca
"net/mlx5: Avoid processing commands before cmdif is ready"
[Test Plan]
* An Ubuntu Server for s390x 18.04 or 20.04 LPAR or z/VM installation
is needed that has Mellanox cards (RoCE Express 2.1) assigned,
configured and enabled and that runs a 5.4 kernel (on bionic hwe-5.4).
* Now trigger a recovery (guess that can be done at the Support Element)
and reload the driver at the same time.
* Make sure the module/driver mlx5 is loaded and in use
(otherwise it can't be removed/unloaded).
* Now remove/unload the module with:
sudo modprobe -r mlx5
and (re-)load it again with:
sudo modprobe mlx5
* Due to the lack of RoCE Express 2.1 hardware,
IBM needs to do the verification.
[Where problems could occur]
* In case there is an issue with 'cmdif' it might not have the correct
interface state, which:
- either might lead to the fact that commands are not properly blocked
and the situation is similar like before
- or the commands may get always blocked,
which render the hardware useless
- or might block in wrong situation,
which will cause unexpected issues and broken behavior.
* Since the patch got upstream accepted with v5.7-rc7 it's
not new to the kernel, was already part of groovy (and above)
and is therefor already in use by newer Ubuntu releases.
[Other Info]
* Since the patch is upstream since v5.7-rc7,
it's already included in jammy and kinetic.
* Since the upstream patch incl. the line:
Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox
Connect-IB adapters") it looks to me that it was forgotten
to mark the patch for upstream stable updates.
* Such SRUs for focal's 5.4 will automatically land in bionic's
hwe-5.4, too. But since this was especially requested for
bionic's hwe-5.4, I wanted to mention this here.
__
We recently got a bug report for systems running Ubuntu 20.04 that were
crashing with backtraces pointing at the mlx5 driver's handling of
mlx5_ethtool_get_link_ksettings()
when this is called through the sysfs (going through ethtool might have
different checks).
I managed to find a reliable way to reproduce the issue that I believe isn't
tied to IBM Z at all.
The procedure to reproduce is as follows. I created a script to read
the sysfs attributes for the link's speed and duplex mode in a loop:
#!/usr/bin/env bash
if [ $# -lt 1 ]; then
echo "Usage: $0 "
exit 1
fi
while true; do
cat /sys/class/net/$1/duplex > /dev/null
cat /sys/class/net/$1/speed > /dev/null
done
Executed with:
# ./script.sh enP10p0s0
I ran this in one bash session and then in another one I triggered a PCI
reset with
the follwoing command where one needs to replace with the PCI address
of the NIC:
echo 1 > /sys/bus/pci/devices//reset
Then first I got a lot of the following messages:
mlx5_core 0010:00:00.0 enP16p0s0: mlx5e_ethtool_get_link_ksettings:
query port ptys failed: -5
An
[Kernel-packages] [Bug 1987287] Comment bridged from LTC Bugzilla
--- Comment From naf...@cn.ibm.com 2022-09-26 04:01 EDT---
@(In reply to comment #21)
> This bug is awaiting verification that the linux/5.4.0-128.144 kernel in
> -proposed solves the problem. Please test the kernel and update this bug
> with the results. If the problem is solved, change the tag
> 'verification-needed-focal' to 'verification-done-focal'. If the problem
> still exists, change the tag 'verification-needed-focal' to
> 'verification-failed-focal'.
>
> If verification is not done by 5 working days from today, this fix will be
> dropped from the source code, and this bug will be closed.
>
> See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to
> enable and use -proposed. Thank you!
@Niklas Schnelle , I also tested this fix on our development mzone, it
works. So please go ahead to next step. Thanks.
root@dal1-qz2-sr3-rk196-s12:/home/sysop# uname -a
Linux dal1-qz2-sr3-rk196-s12 5.4.0-125-generic #141~18.04.1~lp1987287-Ubuntu
SMP Wed Aug 31 08:38:45 UTC 2022 s390x s390x s390x GNU/Linux
It works after we include this lp1987287 fix.
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https://bugs.launchpad.net/bugs/1987287
Title:
[UBUNTU 20.04] mlx5 driver crashes on accessing device attributes
during recovery
Status in Ubuntu on IBM z Systems:
Fix Committed
Status in linux package in Ubuntu:
Invalid
Status in linux source package in Focal:
Fix Committed
Bug description:
SRU Justification:
--
[Impact]
* If the mlx5 driver is reloading while the recovery flow is happening,
and if it receives new commands before the command interface is up
again, this can lead to null pointer that tries to access non-
initialized command structures.
* So it's required to avoid processing commands before the command
interface is up again.
* This is accomplished by a new cmdif state that helps to avoid
processing commands while cmdif is not ready.
[Fix]
* backport of f7936ddd35d8 f7936ddd35d8b849daf0372770c7c9dbe7910fca
"net/mlx5: Avoid processing commands before cmdif is ready"
[Test Plan]
* An Ubuntu Server for s390x 18.04 or 20.04 LPAR or z/VM installation
is needed that has Mellanox cards (RoCE Express 2.1) assigned,
configured and enabled and that runs a 5.4 kernel (on bionic hwe-5.4).
* Now trigger a recovery (guess that can be done at the Support Element)
and reload the driver at the same time.
* Make sure the module/driver mlx5 is loaded and in use
(otherwise it can't be removed/unloaded).
* Now remove/unload the module with:
sudo modprobe -r mlx5
and (re-)load it again with:
sudo modprobe mlx5
* Due to the lack of RoCE Express 2.1 hardware,
IBM needs to do the verification.
[Where problems could occur]
* In case there is an issue with 'cmdif' it might not have the correct
interface state, which:
- either might lead to the fact that commands are not properly blocked
and the situation is similar like before
- or the commands may get always blocked,
which render the hardware useless
- or might block in wrong situation,
which will cause unexpected issues and broken behavior.
* Since the patch got upstream accepted with v5.7-rc7 it's
not new to the kernel, was already part of groovy (and above)
and is therefor already in use by newer Ubuntu releases.
[Other Info]
* Since the patch is upstream since v5.7-rc7,
it's already included in jammy and kinetic.
* Since the upstream patch incl. the line:
Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox
Connect-IB adapters") it looks to me that it was forgotten
to mark the patch for upstream stable updates.
* Such SRUs for focal's 5.4 will automatically land in bionic's
hwe-5.4, too. But since this was especially requested for
bionic's hwe-5.4, I wanted to mention this here.
__
We recently got a bug report for systems running Ubuntu 20.04 that were
crashing with backtraces pointing at the mlx5 driver's handling of
mlx5_ethtool_get_link_ksettings()
when this is called through the sysfs (going through ethtool might have
different checks).
I managed to find a reliable way to reproduce the issue that I believe isn't
tied to IBM Z at all.
The procedure to reproduce is as follows. I created a script to read
the sysfs attributes for the link's speed and duplex mode in a loop:
#!/usr/bin/env bash
if [ $# -lt 1 ]; then
echo "Usage: $0 "
exit 1
fi
while true; do
cat /sys/class/net/$1/duplex > /dev/null
cat /sys/class/net/$1/speed > /dev/null
done
Executed with:
# ./script.sh enP10p0s0
I ran this in one bash session and then in another one I triggered a PCI
reset with
the follwoing command where one needs to replace with the PCI address
of th
[Kernel-packages] [Bug 1987287] Comment bridged from LTC Bugzilla
--- Comment From niklas.schne...@ibm.com 2022-09-05 08:55 EDT---
(In reply to comment #16)
> Hello 'nafeiy', we indeed wanted to pick this up in the next days.
> Just notice that this is a development bug, opened at the Launchpad bug
> tracking system, that is mainly used for development.
>
> We will usually produce a patched 20.04/focal/5.4 test kernel, that we make
> a available via a so called PPA (a special repository).
> It will take then some steps in our SRU cycle until this patched kernel gets
> released.
> These are the upcoming kernel Service Release Cycles (SRUs):
> https://kernel.ubuntu.com/
>
> This 5.4 kernel will then be migrated by our kernel team to
> 18.04/bionic/hwe-5.4.
> But in this case we may also create a dedicated hwe-5.4 test kernel for
> bionic for you, to save you some time.
>
> The process for hotfixes is a different.
Hi Frank, I tested the provided PPA kernel "5.4.0-126-generic
#142~lp1987287-Ubuntu" with the reset while reading duplex/speed test from the
original report.
It worked as expected no crash and a clean recovery. Thanks!
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https://bugs.launchpad.net/bugs/1987287
Title:
[UBUNTU 20.04] mlx5 driver crashes on accessing device attributes
during recovery
Status in Ubuntu on IBM z Systems:
In Progress
Status in linux package in Ubuntu:
Invalid
Status in linux source package in Focal:
In Progress
Bug description:
SRU Justification:
--
[Impact]
* If the mlx5 driver is reloading while the recovery flow is happening,
and if it receives new commands before the command interface is up
again, this can lead to null pointer that tries to access non-
initialized command structures.
* So it's required to avoid processing commands before the command
interface is up again.
* This is accomplished by a new cmdif state that helps to avoid
processing commands while cmdif is not ready.
[Fix]
* backport of f7936ddd35d8 f7936ddd35d8b849daf0372770c7c9dbe7910fca
"net/mlx5: Avoid processing commands before cmdif is ready"
[Test Plan]
* An Ubuntu Server for s390x 18.04 or 20.04 LPAR or z/VM installation
is needed that has Mellanox cards (RoCE Express 2.1) assigned,
configured and enabled and that runs a 5.4 kernel (on bionic hwe-5.4).
* Now trigger a recovery (guess that can be done at the Support Element)
and reload the driver at the same time.
* Make sure the module/driver mlx5 is loaded and in use
(otherwise it can't be removed/unloaded).
* Now remove/unload the module with:
sudo modprobe -r mlx5
and (re-)load it again with:
sudo modprobe mlx5
* Due to the lack of RoCE Express 2.1 hardware,
IBM needs to do the verification.
[Where problems could occur]
* In case there is an issue with 'cmdif' it might not have the correct
interface state, which:
- either might lead to the fact that commands are not properly blocked
and the situation is similar like before
- or the commands may get always blocked,
which render the hardware useless
- or might block in wrong situation,
which will cause unexpected issues and broken behavior.
* Since the patch got upstream accepted with v5.7-rc7 it's
not new to the kernel, was already part of groovy (and above)
and is therefor already in use by newer Ubuntu releases.
[Other Info]
* Since the patch is upstream since v5.7-rc7,
it's already included in jammy and kinetic.
* Since the upstream patch incl. the line:
Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox
Connect-IB adapters") it looks to me that it was forgotten
to mark the patch for upstream stable updates.
* Such SRUs for focal's 5.4 will automatically land in bionic's
hwe-5.4, too. But since this was especially requested for
bionic's hwe-5.4, I wanted to mention this here.
__
We recently got a bug report for systems running Ubuntu 20.04 that were
crashing with backtraces pointing at the mlx5 driver's handling of
mlx5_ethtool_get_link_ksettings()
when this is called through the sysfs (going through ethtool might have
different checks).
I managed to find a reliable way to reproduce the issue that I believe isn't
tied to IBM Z at all.
The procedure to reproduce is as follows. I created a script to read
the sysfs attributes for the link's speed and duplex mode in a loop:
#!/usr/bin/env bash
if [ $# -lt 1 ]; then
echo "Usage: $0 "
exit 1
fi
while true; do
cat /sys/class/net/$1/duplex > /dev/null
cat /sys/class/net/$1/speed > /dev/null
done
Executed with:
# ./script.sh enP10p0s0
I ran this in one bash session and then in another one I triggered a PCI
reset with
the follwoing command where one needs to replace with the PCI address
of the NI
[Kernel-packages] [Bug 1987287] Comment bridged from LTC Bugzilla
--- Comment From naf...@cn.ibm.com 2022-08-30 12:28 EDT--- @Canonical, I'd like to know that when will the fix be back ported to hwe-5.4 kernel? Will it be a new hotpatch like this one ? https://launchpad.net/~canonical-support-eng/+archive/ubuntu/sf334332 or something else. Thanks so much. Sorry I am not familiar with the process, and just like to know how can I include the fix in our cloud environment. Thanks. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1987287 Title: [UBUNTU 20.04] mlx5 driver crashes on accessing device attributes during recovery Status in Ubuntu on IBM z Systems: New Status in linux package in Ubuntu: Invalid Status in linux source package in Focal: New Bug description: We recently got a bug report for systems running Ubuntu 20.04 that were crashing with backtraces pointing at the mlx5 driver's handling of mlx5_ethtool_get_link_ksettings() when this is called through the sysfs (going through ethtool might have different checks). I managed to find a reliable way to reproduce the issue that I believe isn't tied to IBM Z at all. The procedure to reproduce is as follows. I created a script to read the sysfs attributes for the link's speed and duplex mode in a loop: #!/usr/bin/env bash if [ $# -lt 1 ]; then echo "Usage: $0 " exit 1 fi while true; do cat /sys/class/net/$1/duplex > /dev/null cat /sys/class/net/$1/speed > /dev/null done Executed with: # ./script.sh enP10p0s0 I ran this in one bash session and then in another one I triggered a PCI reset with the follwoing command where one needs to replace with the PCI address of the NIC: echo 1 > /sys/bus/pci/devices//reset Then first I got a lot of the following messages: mlx5_core 0010:00:00.0 enP16p0s0: mlx5e_ethtool_get_link_ksettings: query port ptys failed: -5 And then as the mlx5 driver's recovery kicks in the oops as below: [ 659.103947] mlx5_core 0010:00:00.0: wait vital counter value 0x7b399f after 1 iterations [ 659.103947] mlx5_core 0010:00:00.0: mlx5_pci_resume was called [ 659.103966] mlx5_core 0010:00:00.0: firmware version: 14.32.1010 [ 659.104169] Unable to handle kernel pointer dereference in virtual kernel address space [ 659.104171] Failing address: TEID: 0483 [ 659.104172] Fault in home space mode while using kernel ASCE. [ 659.104173] AS:3d29c007 R3:fffd0007 S:fffd5800 P:003d [ 659.104200] Oops: 0004 ilc:2 [#1] SMP [ 659.104202] Modules linked in: s390_trng ism smc pnet chsc_sch eadm_sch vfio_ccw vfio_mdev mdev vfio_iommu_type1 vfio sch_fq_codel drm drm_panel_orientation_quirks i2c_core ip_tables x_tables btrfs zstd_compress zlib_deflate raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 linear mlx5_ib dm_service_time pkey zcrypt crc32_vx_s390 ib_uverbs ghash_s390 ib_core qeth_l2 prng aes_s390 des_s390 nvme libdes sha3_512_s390 sha3_256_s390 sha512_s390 sha256_s390 sha1_s390 sha_common mlx5_core tls mlxfw ptp nvme_core pps_core dasd_eckd_mod dasd_mod zfcp scsi_transport_fc qeth qdio ccwgroup scsi_dh_emc scsi_dh_rdac scsi_dh_alua dm_multipath [ 659.104232] CPU: 6 PID: 438216 Comm: cat Not tainted 5.4.0-124-generic #140-Ubuntu [ 659.104233] Hardware name: IBM 3931 XYZ (LPAR) [ 659.104234] Krnl PSW : 0404c0018000 3bfa661e (__queue_work+0xfe/0x520) [ 659.104241]R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 [ 659.104242] Krnl GPRS: 3c291570 0007 7fff [ 659.104243]e2fe46e0 000fffe0 0006 3d039588 [ 659.104244] e2fe46e0 bfb3e000 [ 659.104245]e194c400 03e007d6fb78 3bfa6602 03e007d6f860 [ 659.104251] Krnl Code: 3bfa6612: a77400e5brc 7,3bfa67dc 3bfa6616: 582003acl %r2,940 #3bfa661a: a718lhi %r1,0 >3bfa661e: ba129000cs %r1,%r2,0(%r9) 3bfa6622: a77401a7brc 7,3bfa6970 3bfa6626: e310b0180012lt %r1,24(%r11) 3bfa662c: a78400ffbrc 8,3bfa682a 3bfa6630: c004004bbrcl 0,3bfa66c6 [ 659.104261] Call Trace: [ 659.104263] ([<>] 0x0) [ 659.104265] [<3bfa6aa2>] queue_work_on+0x62/0x70 [ 659.104329] [<03ff80a2920a>] cmd_exec+0x4e
[Kernel-packages] [Bug 1987287] Comment bridged from LTC Bugzilla
--- Comment From boris.m...@de.ibm.com 2022-08-22 11:48 EDT--- @Canonical: As the problem occurred in the Cloud environment running on a 18.04 HWE kernel, we need to make sure that the fix will also be included there. With adding to focal, will the patch land in 18.04 HWE kernel as well or do we need to open an additional separate bug / launchpad entry for the 18.04 HWE kernel? -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1987287 Title: [UBUNTU 20.04] mlx5 driver crashes on accessing device attributes during recovery Status in Ubuntu on IBM z Systems: New Status in linux package in Ubuntu: Invalid Status in linux source package in Focal: New Bug description: We recently got a bug report for systems running Ubuntu 20.04 that were crashing with backtraces pointing at the mlx5 driver's handling of mlx5_ethtool_get_link_ksettings() when this is called through the sysfs (going through ethtool might have different checks). I managed to find a reliable way to reproduce the issue that I believe isn't tied to IBM Z at all. The procedure to reproduce is as follows. I created a script to read the sysfs attributes for the link's speed and duplex mode in a loop: #!/usr/bin/env bash if [ $# -lt 1 ]; then echo "Usage: $0 " exit 1 fi while true; do cat /sys/class/net/$1/duplex > /dev/null cat /sys/class/net/$1/speed > /dev/null done Executed with: # ./script.sh enP10p0s0 I ran this in one bash session and then in another one I triggered a PCI reset with the follwoing command where one needs to replace with the PCI address of the NIC: echo 1 > /sys/bus/pci/devices//reset Then first I got a lot of the following messages: mlx5_core 0010:00:00.0 enP16p0s0: mlx5e_ethtool_get_link_ksettings: query port ptys failed: -5 And then as the mlx5 driver's recovery kicks in the oops as below: [ 659.103947] mlx5_core 0010:00:00.0: wait vital counter value 0x7b399f after 1 iterations [ 659.103947] mlx5_core 0010:00:00.0: mlx5_pci_resume was called [ 659.103966] mlx5_core 0010:00:00.0: firmware version: 14.32.1010 [ 659.104169] Unable to handle kernel pointer dereference in virtual kernel address space [ 659.104171] Failing address: TEID: 0483 [ 659.104172] Fault in home space mode while using kernel ASCE. [ 659.104173] AS:3d29c007 R3:fffd0007 S:fffd5800 P:003d [ 659.104200] Oops: 0004 ilc:2 [#1] SMP [ 659.104202] Modules linked in: s390_trng ism smc pnet chsc_sch eadm_sch vfio_ccw vfio_mdev mdev vfio_iommu_type1 vfio sch_fq_codel drm drm_panel_orientation_quirks i2c_core ip_tables x_tables btrfs zstd_compress zlib_deflate raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 linear mlx5_ib dm_service_time pkey zcrypt crc32_vx_s390 ib_uverbs ghash_s390 ib_core qeth_l2 prng aes_s390 des_s390 nvme libdes sha3_512_s390 sha3_256_s390 sha512_s390 sha256_s390 sha1_s390 sha_common mlx5_core tls mlxfw ptp nvme_core pps_core dasd_eckd_mod dasd_mod zfcp scsi_transport_fc qeth qdio ccwgroup scsi_dh_emc scsi_dh_rdac scsi_dh_alua dm_multipath [ 659.104232] CPU: 6 PID: 438216 Comm: cat Not tainted 5.4.0-124-generic #140-Ubuntu [ 659.104233] Hardware name: IBM 3931 XYZ (LPAR) [ 659.104234] Krnl PSW : 0404c0018000 3bfa661e (__queue_work+0xfe/0x520) [ 659.104241]R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 RI:0 EA:3 [ 659.104242] Krnl GPRS: 3c291570 0007 7fff [ 659.104243]e2fe46e0 000fffe0 0006 3d039588 [ 659.104244] e2fe46e0 bfb3e000 [ 659.104245]e194c400 03e007d6fb78 3bfa6602 03e007d6f860 [ 659.104251] Krnl Code: 3bfa6612: a77400e5brc 7,3bfa67dc 3bfa6616: 582003acl %r2,940 #3bfa661a: a718lhi %r1,0 >3bfa661e: ba129000cs %r1,%r2,0(%r9) 3bfa6622: a77401a7brc 7,3bfa6970 3bfa6626: e310b0180012lt %r1,24(%r11) 3bfa662c: a78400ffbrc 8,3bfa682a 3bfa6630: c004004bbrcl 0,3bfa66c6 [ 659.104261] Call Trace: [ 659.104263] ([<>] 0x0) [ 659.104265] [<3bfa6aa2>] queue_work_on+0x62/0x70 [ 659.104329] [<03ff80a2920a>] cmd_exec+0x4ea/0x840 [mlx5_core] [ 659.104349]
