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Subject: Re: [RFC PATCH v3 00/22] arm64: livepatch: Use ORC for dynamic frame
 pointer validation
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To:     Dylan Hatch <dylanbhatch@google.com>, misono.tomohiro@fujitsu.com
Cc:     broonie@kernel.org, catalin.marinas@arm.com,
        chenzhongjin@huawei.com, jamorris@linux.microsoft.com,
        jpoimboe@redhat.com, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, live-patching@vger.kernel.org,
        mark.rutland@arm.com, nobuta.keiya@fujitsu.com,
        peterz@infradead.org, pmladek@suse.com, sjitindarsingh@gmail.com,
        will@kernel.org
References: <CADBMgpxQ+oM_TrtKRiREcZoZSk=AfenV_bqOk_Vt-Ov5FPHMvw@mail.gmail.com>
From:   "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com>
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Sorry for the delay. Someone else also pointed out the same thing. I just have not
had the chance to look at this. I plan to soon.

Thanks.

Madhavan

On 4/3/23 17:26, Dylan Hatch wrote:
>> Then, I noticed that invoke_syscall generates instructions to add random offset
>> in sp when RANDOMIZE_KSTACK_OFFSET=y, which is true in the above case.
> 
> I'm also seeing this behavior when compiling with
> RANDOMIZE_KSTACK_OFFSET=y. I wonder if a special hint type
> could/should be added to allow for skipping the reliability check for
> stack frames with this randomized offset? Forgive me if this is a
> naive suggestion.
> 
> Thanks,
> Dylan