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Date:   Tue, 28 Mar 2023 09:02:30 -0400
From:   "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        maple-tree@lists.infradead.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Matthew Wilcox <willy@infradead.org>,
        Suren Baghdasaryan <surenb@google.com>
Subject: Re: [PATCH 0/8] Fix VMA tree modification under mmap read lock
Message-ID: <20230328130230.gdmychfid3aggikd@revolver>
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* Vlastimil Babka <vbabka@suse.cz> [230328 05:11]:
> On 3/27/23 21:48, Liam R. Howlett wrote:
> > * Andrew Morton <akpm@linux-foundation.org> [230327 15:35]:
> >> On Mon, 27 Mar 2023 14:55:24 -0400 "Liam R. Howlett" <Liam.Howlett@oracle.com> wrote:
> >> 
> >> > These patches have been in -next since next-20230301, and have received
> >> > intensive testing in Android as part of the RCU page fault patchset.
> >> > They were also sent as part of the "Per-VMA locks" v4 patch series.
> >> > Patches 1 to 7 are bug fixes for RCU mode of the tree and patch 8 enables
> >> > RCU mode for the tree.
> >> 
> >> What's happening here?  I assume you've decided that the first 8
> >> patches of the "Per-VMA locks v4" series should be fast-tracked into
> >> 6.3-rcX and backported?  And we retain the rest of that series for
> >> 6.4-rc1?
> > 
> > Yes, they need to be backported and fast tracked to fix the issue syzbot
> > found.
> 
> Stable usually wants the "mainline first" which means fast tracking first,
> then once it's in mainline, they pick it and annotate with mainline commit id.

Right.  I meant these patches won't cleanly apply to 6.1/6.2 and will
need more than just a cherry-pick due to the vma iterator changes.  I
have those modified patches ready to go as well.

> 
> One question is how Linus would feel about this now for rc5.
> 
> Another question is if we should really deviate in the patch 8/8 backport
> just because it's not necessary for stable. Generally they would also prefer
> not to deviate, unless there's a strong reason.

Just to clarify, the change is to remove something that isn't necessary
at all.

> 
> >> 
> >> Patch [3/8] hasn't come through to me, to linux-mm or to linux-kernel.
> > 
> > Should arrive shortly, I received it from one of the ML.
> > 
> > 
> 
> 
> -- 
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