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Date: Tue, 19 Jun 2018 16:24:36 +0100
From: Catalin Marinas <catalin.marinas@arm.com>
To: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org, will.deacon@arm.com,
        marc.zyngier@arm.com, linux@dominikbrodowski.net,
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Subject: Re: [PATCHv3 12/19] arm64: zero GPRs upon entry from EL0
Message-ID: <20180619152436.7lvsmiq2wseo4u6e@armageddon.cambridge.arm.com>
References: <20180618120310.39527-1-mark.rutland@arm.com>
 <20180618120310.39527-13-mark.rutland@arm.com>
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On Mon, Jun 18, 2018 at 01:03:03PM +0100, Mark Rutland wrote:
> We can zero GPRs x0 - x29 upon entry from EL0 to make it harder for
> userspace to control values consumed by speculative gadgets.
> 
> We don't blat x30, since this is stashed much later, and we'll blat it
> before invoking C code.
> 
> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will.deacon@arm.com>

Acked-by: Catalin Marinas <catalin.marinas@arm.com>