linux-kernel - Re: [RFC PATCH v3 4/4] arm64: Handle funtion graph tracer better in the unwinder

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <f6616a1a-1291-b9b1-17d6-aed40f4a2b55@linux.microsoft.com>
Date:   Thu, 6 May 2021 10:20:35 -0500
From:   "Madhavan T. Venkataraman" <madvenka@...ux.microsoft.com>
To:     Mark Brown <broonie@...nel.org>
Cc:     jpoimboe@...hat.com, mark.rutland@....com, jthierry@...hat.com,
        catalin.marinas@....com, will@...nel.org, jmorris@...ei.org,
        pasha.tatashin@...een.com, linux-arm-kernel@...ts.infradead.org,
        live-patching@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH v3 4/4] arm64: Handle funtion graph tracer better in
 the unwinder



On 5/6/21 9:43 AM, Mark Brown wrote:
> On Mon, May 03, 2021 at 12:36:15PM -0500, madvenka@...ux.microsoft.com wrote:
>> From: "Madhavan T. Venkataraman" <madvenka@...ux.microsoft.com>
>>
>> The Function Graph Tracer modifies the return address of a traced function
>> to a return trampoline (return_to_handler()) to gather tracing data on
>> function return. When the unwinder encounters return_to_handler(), it calls
>> ftrace_graph_get_ret_stack() to lookup the original return address in the
>> return address stack.
> 
> This makes sense to me, I'll need to re-review properly with the changes
> earlier on in the series but should be fine.
> 

I will make changes based on the comments I have received so far and send
out version 4 so everything is current for the next round of review.

Thanks!

Madhavan