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SubjectRe: [PATCH v2]: perf/x86: store user space frame-pointer value on a sample
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Hi Peter,

On 10.05.2018 13:14, Peter Zijlstra wrote:
> On Thu, May 10, 2018 at 12:42:38PM +0300, Alexey Budankov wrote:
>>> The Changelog needs to state that user_regs->bp is in fact valid and
>>
>> That actually was tested on binaries compiled without and with BP exposed
>> and in the latter case proved the value of that change.
>
> Mostly works is not the same as 'always initialized', if there are entry
> paths that do not store that register, then using the value might leak
> values from the kernel stack, which would be bad.
>
> But like said, I think much of the kernel entry code was sanitized with
> the PTI effort and I suspect things are in fact fine now, but lets wait
> for Andy to confirm.
>

It looks like Andy confirmed on the questions above.

Is the patch ready to be up streamed now?

Thanks,
Alexey

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