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    SubjectRe: [PATCH AUTOSEL 5.19 05/58] arm64: kernel: drop unnecessary PoC cache clean+invalidate
    On Mon, Aug 08, 2022 at 11:05:29AM +0200, Ard Biesheuvel wrote:
    >On Mon, 8 Aug 2022 at 03:31, Sasha Levin <sashal@kernel.org> wrote:
    >>
    >> From: Ard Biesheuvel <ardb@kernel.org>
    >>
    >> [ Upstream commit 2e945851e26836c0f2d34be3763ddf55870e49fe ]
    >>
    >> Some early boot code runs before the virtual placement of the kernel is
    >> finalized, and we used to go back to the very start and recreate the ID
    >> map along with the page tables describing the virtual kernel mapping,
    >> and this involved setting some global variables with the caches off.
    >>
    >> In order to ensure that global state created by the KASLR code is not
    >> corrupted by the cache invalidation that occurs in that case, we needed
    >> to clean those global variables to the PoC explicitly.
    >>
    >> This is no longer needed now that the ID map is created only once (and
    >> the associated global variable updates are no longer repeated). So drop
    >> the cache maintenance that is no longer necessary.
    >>
    >> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
    >> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
    >> Link: https://lore.kernel.org/r/20220624150651.1358849-9-ardb@kernel.org
    >> Signed-off-by: Will Deacon <will@kernel.org>
    >> Signed-off-by: Sasha Levin <sashal@kernel.org>
    >
    >NAK
    >
    >This patch *must* *not* be backported. It will break the boot.

    Appologies for this one, this was a technical issue on my end and I owe
    a beer for yourself and few other folks that should have been filtered
    out.

    I'll drop all your patches from the AUTOSEL queue.

    --
    Thanks,
    Sasha

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