From: Andrew Morton <akpm@linux-foundation.org>
To: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Yu Zhao <yuzhao@google.com>,
peterz@infradead.org, tglx@linutronix.de, david@redhat.com,
jannh@google.com, hughd@google.com, willy@infradead.org,
muchun.song@linux.dev, vbabka@kernel.org,
lorenzo.stoakes@oracle.com, rientjes@google.com,
linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 01/12] Revert "mm: pgtable: make ptlock be freed by RCU"
Date: Sun, 15 Dec 2024 22:35:42 -0800 [thread overview]
Message-ID: <20241215223542.2b8e45a7d68f6ebc71b5ce3a@linux-foundation.org> (raw)
In-Reply-To: <eef6abd4-327b-4f7c-8b3f-b2552fa78952@bytedance.com>
On Mon, 16 Dec 2024 14:15:35 +0800 Qi Zheng <zhengqi.arch@bytedance.com> wrote:
> Hi Andrew,
>
> On 2024/12/16 14:10, Andrew Morton wrote:
> > On Sun, 15 Dec 2024 14:29:38 +0800 Qi Zheng <zhengqi.arch@bytedance.com> wrote:
> >
> >>>
> >>> Acked-by: Yu Zhao <yuzhao@google.com>
> >>
> >> Thanks! Once the review of this patch series is completed, we can simply
> >> drop "mm: pgtable: make ptlock be freed by RCU" from mm tree.
> >
> > Can we drop it now and does the remainder of the series "synchronously
> > scan and reclaim empty user PTE pages v4" remain valid and useful?
>
> The "mm: pgtable: make ptlock be freed by RCU" fixes the UAF issue [1]
> reported by syzbot. If it is dropped now and this patch series is not
> merged, the UAF issue will reappear.
>
> [1].
> https://lore.kernel.org/lkml/67548279.050a0220.a30f1.015b.GAE@google.com/
OK, so as I understand it,
- the series "synchronously scan and reclaim empty user PTE pages v4"
exposes a use-after-free bug, and fixes that bug with the patch "mm:
pgtable: make ptlock be freed by RCU".
- The series "move pagetable_*_dtor() to __tlb_remove_table()" fixes
that bug in a more desirable way.
- So when the series "move pagetable_*_dtor() to
__tlb_remove_table()" is merged into mm-unstable, I drop the patch
"mm: pgtable: make ptlock be freed by RCU".
Correct?
next prev parent reply other threads:[~2024-12-16 6:35 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-12-14 9:02 [PATCH 00/12] move pagetable_*_dtor() to __tlb_remove_table() Qi Zheng
2024-12-14 9:02 ` [PATCH 01/12] Revert "mm: pgtable: make ptlock be freed by RCU" Qi Zheng
2024-12-14 18:29 ` Yu Zhao
2024-12-15 6:29 ` Qi Zheng
2024-12-16 6:10 ` Andrew Morton
2024-12-16 6:15 ` Qi Zheng
2024-12-16 6:35 ` Andrew Morton [this message]
2024-12-16 6:39 ` Qi Zheng
2024-12-14 9:02 ` [PATCH 02/12] mm: pgtable: introduce generic p4d_alloc_one() and p4d_free() Qi Zheng
2024-12-18 14:26 ` Klara Modin
2024-12-18 14:42 ` Qi Zheng
2024-12-14 9:02 ` [PATCH 03/12] arm64: pgtable: use mmu gather to free p4d level page table Qi Zheng
2024-12-14 9:02 ` [PATCH 04/12] s390: pgtable: add statistics for PUD and P4D " Qi Zheng
2024-12-14 9:02 ` [PATCH 05/12] mm: pgtable: introduce pagetable_dtor() Qi Zheng
2024-12-14 9:02 ` [PATCH 06/12] arm: pgtable: move pagetable_dtor() to __tlb_remove_table() Qi Zheng
2024-12-14 9:02 ` [PATCH 07/12] arm64: " Qi Zheng
2024-12-14 9:02 ` [PATCH 08/12] riscv: " Qi Zheng
2024-12-14 9:02 ` [PATCH 09/12] x86: " Qi Zheng
2024-12-14 9:02 ` [PATCH 10/12] s390: pgtable: also move pagetable_dtor() of PxD " Qi Zheng
2024-12-14 9:02 ` [PATCH 11/12] mm: pgtable: introduce generic __tlb_remove_table() Qi Zheng
2024-12-16 12:00 ` Peter Zijlstra
2024-12-16 12:03 ` Peter Zijlstra
2024-12-16 12:05 ` Peter Zijlstra
2024-12-16 13:53 ` Qi Zheng
2024-12-16 12:52 ` Qi Zheng
2024-12-16 18:12 ` Peter Zijlstra
2024-12-17 3:42 ` Qi Zheng
2024-12-17 9:02 ` Peter Zijlstra
2024-12-17 9:10 ` Qi Zheng
2024-12-14 9:02 ` [PATCH 12/12] mm: pgtable: move __tlb_remove_table_one() in x86 to generic file Qi Zheng
2024-12-14 18:55 ` [PATCH 00/12] move pagetable_*_dtor() to __tlb_remove_table() Peter Zijlstra
2024-12-15 6:23 ` Qi Zheng
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20241215223542.2b8e45a7d68f6ebc71b5ce3a@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=david@redhat.com \
--cc=hughd@google.com \
--cc=jannh@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=lorenzo.stoakes@oracle.com \
--cc=muchun.song@linux.dev \
--cc=peterz@infradead.org \
--cc=rientjes@google.com \
--cc=tglx@linutronix.de \
--cc=vbabka@kernel.org \
--cc=willy@infradead.org \
--cc=yuzhao@google.com \
--cc=zhengqi.arch@bytedance.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox