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    Subject[PATCH v5 39/44] x86: fs: kmsan: disable CONFIG_DCACHE_WORD_ACCESS
    From
    dentry_string_cmp() calls read_word_at_a_time(), which might read
    uninitialized bytes to optimize string comparisons.
    Disabling CONFIG_DCACHE_WORD_ACCESS should prohibit this optimization,
    as well as (probably) similar ones.

    Suggested-by: Andrey Konovalov <andreyknvl@gmail.com>
    Signed-off-by: Alexander Potapenko <glider@google.com>
    ---
    Link: https://linux-review.googlesource.com/id/I4c0073224ac2897cafb8c037362c49dda9cfa133
    ---
    arch/x86/Kconfig | 4 +++-
    1 file changed, 3 insertions(+), 1 deletion(-)

    diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
    index 33f4d4baba079..697da8dae1418 100644
    --- a/arch/x86/Kconfig
    +++ b/arch/x86/Kconfig
    @@ -128,7 +128,9 @@ config X86
    select CLKEVT_I8253
    select CLOCKSOURCE_VALIDATE_LAST_CYCLE
    select CLOCKSOURCE_WATCHDOG
    - select DCACHE_WORD_ACCESS
    + # Word-size accesses may read uninitialized data past the trailing \0
    + # in strings and cause false KMSAN reports.
    + select DCACHE_WORD_ACCESS if !KMSAN
    select DYNAMIC_SIGFRAME
    select EDAC_ATOMIC_SCRUB
    select EDAC_SUPPORT
    --
    2.37.2.672.g94769d06f0-goog
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