APPLIED [J,L]: [PATCH 0/1][SRU][J][L][M] A deadlock issue in scsi rescan task while resuming from S3

[Roxana Nicolescu]

On 20/06/2023 05:36, AceLan Kao wrote:
> From: "Chia-Lin Kao (AceLan)" <acelan.kao at canonical.com>
>
> BugLink: https://launchpad.net/bugs/2018566
>
> [Impact]
> During the S3 stress test, the system sometimes hangs when resuming. This
> is due to the SCSI rescan task being unable to acquire the mutex lock
> during the resumption from S3. The mutex lock has already been acquired by
> EH and is waiting for the device to be ready for a rescan. Unfortunately,
> the mutex lock is never released by either party, leading to a deadlock.
>
> [Fix]
> Kaiheng submitted a patch to fix this issue which defers the rescan if the
> disk is still suspended so the resume process of the disk device can proceed.
> https://patchwork.ozlabs.org/project/linux-ide/patch/20230502150435.423770-2-kai.heng.feng@canonical.com/
>
> Since the patch has not been accepted by the upstream yet, so submit it to the OEM kernel for now.
>
> The similiar patch has been included in v6.4-rc7, backport this to
> generic ubuntu kernels.
> 6aa0365a3c85 ata: libata-scsi: Avoid deadlock on rescan after device resume
>
> [Test]
> Verified on the machines by me and ODM.
>
> [Where problems could occur]
> It only defers the rescan task, and should not have any impact to current systems.
>
> Damien Le Moal (1):
>    ata: libata-scsi: Avoid deadlock on rescan after device resume
>
>   drivers/ata/libata-core.c |  3 ++-
>   drivers/ata/libata-eh.c   |  2 +-
>   drivers/ata/libata-scsi.c | 22 +++++++++++++++++++++-
>   include/linux/libata.h    |  2 +-
>   4 files changed, 25 insertions(+), 4 deletions(-)
>
Applied to lunar/jammy:master-next. I adjusted the buglink accordingly. 
Thanks.

Roxana