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    SubjectRe: [PATCH v2 0/6] wchan: Fix ORC support and leaky fallback
    On Wed, Sep 29, 2021 at 03:02:12PM -0700, Kees Cook wrote:
    > Hi,
    >
    > This attempts to solve the issues from the discussion here[1]. Specifically:
    >
    > 1) wchan leaking raw addresses since 152c432b128c (v5.12).
    >
    > patch 1 fixes this with a revert.
    >
    > 2) wchan has been broken under ORC, seen as a failure to stack walk
    > resulting in _usually_ a 0 value, since ee9f8fce9964 (v4.14).
    >
    > patches 2-5 fixes this with Qi Zheng's new get_wchan() and changes to
    > the /proc code to use the new helper suggested by Peter to do the stack
    > walk only if the process can be kept blocked:
    > https://lore.kernel.org/lkml/20210929194026.GA4323@worktop.programming.kicks-ass.net/
    >
    > Peter, can you take this via -tip?

    It all looks sane to me. Thanks for cleaning up this mess.

    - Should we use a similar sched wrapper for /proc/$pid/stack to make its
    raciness go away?

    - At the risk of triggering a much larger patch set, I suspect
    get_wchan() can be made generic ;-) It's just a glorified wrapper
    around stack_trace_save_tsk().

    Regardless:

    Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>

    --
    Josh

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