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From: Harry Yoo <harry@kernel.org>
To: Vitaly Wool <vitaly.wool@konsulko.se>
Cc: akpm@linux-foundation.org, cl@gentwo.org, hao.li@linux.dev,
	hch@lst.de,  linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	nickolai@csail.mit.edu, rientjes@google.com,
	 roman.gushchin@linux.dev, vbabka@kernel.org,
	vitaly.vul@partner.samsung.com
Subject: Re: [PATCH v1] mempool: fix min_nr exceeding the elements array after concurrent resizes
Date: Mon, 19 Oct 2026 14:27:01 +0100	[thread overview]
Message-ID: <atYZnuRTTG7iweuK@thinkstation> (raw)
In-Reply-To: <F846CE95-6D2A-4D53-9C09-5C8630E2C8A7@konsulko.se>

On Mon, Oct 19, 2026 at 08:45:55AM +0200, Vitaly Wool wrote:
> 
> 
> > On Oct 18, 2026, at 6:15 PM, Harry Yoo <harry@kernel.org> wrote:
> > 
> > On Sun, Oct 18, 2026 at 06:03:15PM +0200, Vitaly Wool wrote:
> >>>> How about we take my patch [1] instead since
> >>>> it isn't prone to this bug and is a nice optimization to the existing
> >>>> mempool_resize() at the same time?
> >>> 
> >>> It is not a good idea to squeeze a bug fix and an optimization
> >>> into one patch.
> >> 
> >> Generally speaking, yes. But that patch had been submitted before the fix
> >> popped up, so there was no sqeezing per se.
> > 
> > I mean the patch you've submitted does two things (wihch is not good).
> > 
> > It should be split into two patches that 1) fixes the bug and 2)
> > optimizes it.
> 
> I don’t think this is a fair statement. I would say that the patch
> I’ve submitted improves mempool_resize() to be rid of unnecessary
> reallocations and data copying, and that (improved) implementation is
> *not* prone to the race found in the previous version of this function.

We backport bugfixes to -stable, but don't want to backport
performance optimizations to -stable in general.

-- 
Cheers,
Harry / Hyeonggon


  reply	other threads:[~2026-10-19 13:27 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-10-16 13:25 [PATCH v1] mempool: fix min_nr exceeding the elements array after concurrent resizes Nickolai Zeldovich
2026-10-16 15:46 ` Harry Yoo
2026-10-16 16:33   ` Nickolai Zeldovich
2026-10-18 15:01   ` Vitaly Wool
2026-10-18 15:15     ` Harry Yoo
2026-10-18 16:03       ` Vitaly Wool
2026-10-18 16:15         ` Harry Yoo
2026-10-19  6:45           ` Vitaly Wool
2026-10-19 13:27             ` Harry Yoo [this message]
2026-10-20  8:27             ` Vlastimil Babka (SUSE)
2026-10-20 10:50               ` Vitaly Wool
2026-10-20 10:57                 ` Harry Yoo
2026-10-20  8:42   ` Vlastimil Babka (SUSE)

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