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Date:   Fri, 2 Mar 2018 10:10:49 +0100
From:   Joerg Roedel <joro@8bytes.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Brian Gerst <brgerst@gmail.com>, Joerg Roedel <jroedel@suse.de>,
        Waiman Long <longman@redhat.com>,
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Subject: Re: [PATCH 12/31] x86/entry/32: Add PTI cr3 switch to non-NMI
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On Thu, Mar 01, 2018 at 10:38:21AM -0800, Linus Torvalds wrote:
> Note that debug traps can happen regardless of TF, Think kgdb etc.
> Arguably kgdb users get what they deserve, but still.. I think root
> can set kernel breakpoints too.

But that seems to be broken right now at least wrt. to the espfix code
where there is no handling for in the #DB handler. Can userspace really
set arbitrary kernel breakpoints?


	Joerg