From: Ignacio Encinas Rubio <ignacio@iencinas.com>
To: syzbot+419c4b42acc36c420ad3@syzkaller.appspotmail.com
Cc: akpm@linux-foundation.org, hughd@google.com,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
syzkaller-bugs@googlegroups.com,
linux-kernel-mentees@lists.linux.dev, skhan@linuxfoundation.org
Subject: Re: [syzbot] [mm?] KCSAN: data-race in try_to_migrate_one / zap_page_range_single
Date: Sat, 15 Mar 2025 12:52:55 +0100 [thread overview]
Message-ID: <4a061ceb-8504-43ae-b1eb-a5ab43811de7@iencinas.com> (raw)
In-Reply-To: <67b44eb7.050a0220.173698.004a.GAE@google.com>
Hello!
This seems like a recurrent complaint from KCSAN (other examples are
[1], [2]).
From what I understand looking at the source code, imprecise reporting
of the maximum resident set size is considered to be acceptable.
Annotating `hiwater_rss` as `__data_racy` [3] should make KCSAN happy.
Would this be an acceptable change? Another possibility would be making
the update from `update_hiwater_rss` atomic, but it doesn't seem worth
the potential slowdown.
Let me know if my proposal works for you.
Thanks!
[1] https://syzkaller.appspot.com/bug?extid=73d65fc86d6338db5990
[2] https://syzkaller.appspot.com/bug?extid=31cd52ba68feee156393
[3] https://docs.kernel.org/dev-tools/kcsan.html#selective-analysis
prev parent reply other threads:[~2025-03-15 11:53 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-18 9:11 syzbot
2025-03-15 11:52 ` Ignacio Encinas Rubio [this message]
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