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Subject: Re: [PATCH 2/2] arm64: Clear the stack
From:   Laura Abbott <labbott@redhat.com>
To:     Mark Rutland <mark.rutland@arm.com>
Cc:     Alexander Popov <alex.popov@linux.com>,
        Kees Cook <keescook@chromium.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        kernel-hardening@lists.openwall.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20180221011303.20392-1-labbott@redhat.com>
 <20180221011303.20392-3-labbott@redhat.com>
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Message-ID: <572af610-c20f-e826-f124-8df47680795b@redhat.com>
Date:   Wed, 21 Feb 2018 17:35:24 -0800
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On 02/21/2018 03:53 PM, Laura Abbott wrote:
>> I *think* this should happen in finish_ret_to_user a few lines down, since we
>> can call C code if we branch to work_pending, dirtying the stack.
>>
> 
> I think you're right but this didn't immediately work when I tried it.
> I'll have to dig into this some more.

Okay I figured this out. Not corrupting registers works wonders.