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From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Kostya Serebryany <kcc@google.com>,
        Peter Collingbourne <pcc@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        Dave Martin <Dave.Martin@arm.com>,
        Evgenii Stepanov <eugenis@google.com>,
        Will Deacon <will@kernel.org>
Cc:     linux-api@vger.kernel.org,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Andrey Konovalov <andreyknvl@google.com>
Subject: Re: [PATCH 1/2] kasan: arm64: set TCR_EL1.TBID1 when enabled
Date:   Wed, 25 Nov 2020 18:54:52 +0000
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On Sat, 21 Nov 2020 01:59:02 -0800, Peter Collingbourne wrote:
> On hardware supporting pointer authentication, we previously ended up
> enabling TBI on instruction accesses when tag-based ASAN was enabled,
> but this was costing us 8 bits of PAC entropy, which was unnecessary
> since tag-based ASAN does not require TBI on instruction accesses. Get
> them back by setting TCR_EL1.TBID1.

Applied to arm64 (for-next/misc), thanks!

[1/2] kasan: arm64: set TCR_EL1.TBID1 when enabled
      https://git.kernel.org/arm64/c/49b3cf035edc

This patch looks safe. Patch 2/2 needs more discussions.

-- 
Catalin