Re: [PATCH 2/6] ipc: reorganize initialization of kern_ipc_perm.seq

From: Manfred Spraul
Date: Thu Jul 05 2018 - 11:12:43 EST


Hi Dmitry,

On 07/05/2018 10:36 AM, Dmitry Vyukov wrote:
[...]
Hi Manfred,

The series looks like a significant improvement to me. Thanks!

I feel that this code can be further simplified (unless I am missing
something here). Please take a look at this version:

https://github.com/dvyukov/linux/commit/f77aeaf80f3c4ab524db92184d874b03063fea3a?diff=split

This is on top of your patches. It basically does the same as your
code, but consolidates all id/seq assignment and dealing with next_id,
and deduplicates code re CONFIG_CHECKPOINT_RESTORE. Currently it's a
bit tricky to follow e.g. where exactly next_id is consumed and where
it needs to be left intact.
The only difference is that my code assigns new->id earlier. Not sure
if it can lead to anything bad. But if yes, then it seems that
currently uninitialized new->id is exposed. If necessary (?) we could
reset new->id in the same place where we set new->deleted.
Everything looks correct for me, it is better than the current code.
Except that you didn't sign off your last patch.

As next step: Who can merge the patches towards linux-next?
The only open point that I see are stress tests of the error codepaths.

And:
I don't think that the patches are relevant for linux-stable, correct?

--
ÂÂÂ Manfred