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SubjectRe: [PATCH v2 0/9] thread_info: use helpers to snapshot thread flags
On Mon, Jun 21, 2021 at 10:05:52AM +0100, Mark Rutland wrote:
> As thread_info::flags scan be manipulated by remote threads, it is
> necessary to use atomics or READ_ONCE() to ensure that code manipulates
> a consistent snapshot, but we open-code plain accesses to
> thread_info::flags across the kernel tree.
>
> Generally we get away with this, but tools like KCSAN legitimately warn
> that there is a data-race, and this is potentially fragile with compiler
> optimizations, LTO, etc.
>
> These patches introduce new helpers to snahpshot the thread flags, with
> the intent being that these should replace all plain accesses.
>
> Since v1 [1]:
> * Drop RFC
> * Make read_ti_thread_flags() __always_inline
> * Clarify commit messages
> * Fix typo in arm64 patch
> * Accumulate Reviewed-by / Acked-by tags
> * Drop powerpc patch to avoid potential conflicts (per [2])
>
> [1] https://lore.kernel.org/r/20210609122001.18277-1-mark.rutland@arm.com
> [2] https://lore.kernel.org/r/87k0mvtgeb.fsf@mpe.ellerman.id.au
>
> Thanks,
> Mark.
>
> Mark Rutland (9):
> thread_info: add helpers to snapshot thread flags
> entry: snapshot thread flags
> sched: snapshot thread flags
> alpha: snapshot thread flags
> arm: snapshot thread flags
> arm64: snapshot thread flags

FWIW, you have two identical arm64 patches in this series, just with a
different subject. For the one you decide to keep:

Acked-by: Will Deacon <will@kernel.org>

Will

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