Re: [MAINTAINERS SUMMIT] [4/4] Discuss how to better prevent backports of commits that turn out to cause regressions

Vlastimil Babka
2024-06-17T10:59:44Z

On 6/14/24 8:47 PM, Sasha Levin wrote:
> On Thu, Jun 13, 2024 at 11:11:54AM -0400, James Bottomley wrote:
>>On Thu, 2024-06-13 at 16:02 +0200, Greg KH wrote:
>>> On Thu, Jun 13, 2024 at 09:56:56AM -0400, James Bottomley wrote:
>>> > On Thu, 2024-06-13 at 09:06 -0400, Sasha Levin wrote:
>>[...]
>>> > > Could you provide a concrete example? This shouldn't happen.
>>> >
>>> > This one has no fixes or cc stable:
>>> >
>>> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=37f1663c91934f664fb850306708094a324c227c
>>> >
>>> > Yet here it is backported:
>>> >
>>> > Message-id: 20240603121056.1837607-1-sashal@kernel.org
>>> >
>>> > (I can't give a lore reference because conveniently it was a
>>> > personal cc with no tracked mailing list).
>>> >
>>> > I picked that one because we discovered a bug with the strlcpy to
>>> > strscpy conversions in SCSI which it looks like this backport has.
>>>
>>> It says, in the commit message:
>>>          Stable-dep-of: c3408c4ae041 ("scsi: qla2xxx: Avoid possible
>>> run-time warning with long model_num")
>>>
>>> That is why it was backported.
>>
>>Well, that still tracks back to a patch which wasn't tagged:
>>c3408c4ae041 is actually fixing a bug in 527e9b704c3d which is another
>>of the strlcpy to strscpy patches which also has no cc:stable or fixes
>>tag:
>>
>>https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=527e9b704c3d
>
> Nor was it ever backported to any stable tree... What am I missing?

What I'm missing is why 37f1663c919 was backported with "Stable-dep-of:
c3408c4ae041" while c3408c4ae041 was not backported?