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Date: Thu, 14 Sep 2017 17:37:20 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: John Ogness <john.ogness@linutronix.de>
cc: Andy Lutomirski <luto@kernel.org>, Al Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: [PATCH] fs/proc: report eip/esp in /prod/PID/stat for
 coredumping
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On Thu, 14 Sep 2017, John Ogness wrote:

> Commit 0a1eb2d474ed ("fs/proc: Stop reporting eip and esp in
> /proc/PID/stat") stopped reporting eip/esp because it is
> racey and dangerous for executing tasks. The comment adds:
> 
>     As far as I know, there are no use programs that make any
>     material use of these fields, so just get rid of them.
> 
> However, existing userspace core-dump-handler applications (for
> example, minicoredumper) are using these fields since they
> provide an excellent cross-platform interface to these valuable
> pointers. So that commit introduced a user space visible
> regression.
> 
> Partially revert the change and make the readout possible for
> tasks with the proper permissions and only if the target task
> has the PF_DUMPCORE flag set.

Duh, I completely forgot about mini core dumper when I acked that commit.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>