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Subject: Re: [PATCH v3 00/20] Speculative page faults
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
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From: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Date: Wed, 4 Oct 2017 08:50:49 +0200
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On 25/09/2017 18:27, Alexei Starovoitov wrote:
> On Mon, Sep 18, 2017 at 12:15 AM, Laurent Dufour
> <ldufour@linux.vnet.ibm.com> wrote:
>> Despite the unprovable lockdep warning raised by Sergey, I didn't get any
>> feedback on this series.
>>
>> Is there a chance to get it moved upstream ?
> 
> what is the status ?
> We're eagerly looking forward for this set to land,
> since we have several use cases for tracing that
> will build on top of this set as discussed at Plumbers.

Hi Alexei,

Based on Plumber's note [1], it sounds that the use case is tied to the BPF
tracing where a call tp find_vma() call will be made on a process's context
to fetch user space's symbols.

Am I right ?
Is the find_vma() call made in the context of the process owning the mm
struct ?

Thanks,
Laurent.

[1] https://etherpad.openstack.org/p/LPC2017_Tracing)