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Date: Sun, 7 Apr 2024 18:50:13 +0800
From: Pengfei Xu <pengfei.xu@intel.com>
To: Alexander Wetzel <alexander@wetzel-home.de>
CC: syzbot <syzbot+93cdc797590ffc710918@syzkaller.appspotmail.com>,
	<dgilbert@interlog.com>, <jejb@linux.ibm.com>,
	<linux-kernel@vger.kernel.org>, <linux-scsi@vger.kernel.org>,
	<martin.petersen@oracle.com>, <syzkaller-bugs@googlegroups.com>
Subject: Re: [syzbot] [scsi?] WARNING in sg_remove_sfp_usercontext
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Hi Alexander,

On 2024-04-04 at 14:05:12 +0200, Alexander Wetzel wrote:
> On 04.04.24 12:57, Pengfei Xu wrote:
> > cc Alexander Wetzel,
> > 
> > I used syzkaller and found the similar problem.
> > 
> > And bisected and found the related commit:
> > 27f58c04a8f4 scsi: sg: Avoid sg device teardown race
> > Reverted the commit on top of v6.9-rc2, this issue was gone.
> 
> There were now multiple reports about the issue. The first (main) discussion
> and fix is here:
> https://lore.kernel.org/all/20240401191038.18359-1-Alexander@wetzel-home.de/
> 
> In a nutshell:
> The new WARN_ON_ONCE() was a (very) stupid idea and must be undone.
> It's ok to just drop the line with the WARN_ON_ONCE(). The rest of the
> proposed patch fixes a much less urgent issue.

  Got it, thanks for your description!

> 
> Of course I can also break the fix into two patches, when this speeds up the
> merge...

Thank you, if it makes sense and accelerates the merge process.

Best Regards,
Thanks1

> 
> Alexander