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

[Andrei Gherzan]

On 23/06/20 09:53AM, Stefan Bader wrote:
> On 20.06.23 05:36, AceLan Kao wrote:
> > From: "Chia-Lin Kao (AceLan)" <acelan.kao at canonical.com>
> > 
> > BugLink: https://launchpad.net/bugs/2018566
>                                    ^ bugs.launchpad.net
> > 
> > [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.
> 
> This is no longer true. The submitted patch is upstream as of v6.4-rc7.
> Updating old justifications might help to convince others to look at this
> more favorably.

As Stefan mentioned, this is already in :

v6.4
v6.4-rc7

> > 
> > 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(-)
> > 
> 
> Anyhow, the submitted patch appears to be identical to upstream.
> 
> Acked-by: Stefan Bader <stefan.bader at canonical.com>
> 

Acked-by: Andrei Gherzan <andrei.gherzan at canonical.com>

-- 
Andrei Gherzan
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