Re: [PATCH 1/4] mm: kmemleak: confirm suspected leaks with a second scan
Geert Uytterhoeven <[email protected]> Mon, 13 Jul 2026 14:36:30 +0200
| Newsgroups | org.kernel.vger.workflows,org.kernel.vger.linux-doc,org.kernel.vger.linux-kernel,org.kernel.vger.linux-kselftest,org.kvack.linux-mm |
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| Message-ID | <CAMuHMdWBQ-Vn4XzbrfV31adY7cEjLvmGuwu5_x7rn1NBkEC5mA@mail.gmail.com> |
Hi Breno, On Mon, 13 Jul 2026 at 13:48, Breno Leitao <[email protected]> wrote: > From: Catalin Marinas <[email protected]> > > The kmemleak marking phase is not atomic. While the object graph is > traversed, the kernel can modify pointers, free objects or allocate new > ones. If a reference to an object is moved from one location to another, > kmemleak scanning may miss it. We have explicit annotations like > kmemleak_transient_leak() but identifying and maintaining them is not > trivial. > > Given that such transient leaks are short-lived, rather than just > reporting such objects as leaks, do another scan to confirm the > suspected objects. If no new leaks are found during the first scan, skip > the confirmation one. > > Signed-off-by: Catalin Marinas <[email protected]> > Assisted-by: Claude:claude-opus-4-8 > Signed-off-by: Breno Leitao <[email protected]> > Cc: Andrew Morton <[email protected]> Thanks for your patch! For how long does this postpone the reporting of a real leak? I am asking, because I have a few known leaks in my local tree, and it already takes a while before they are reported. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected] In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds