From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <jroedel@suse.de>
Subject: Re: [PATCH v4 63/75] x86/sev-es: Handle #DB Events
Date: Wed, 15 Jul 2020 12:31:20 +0200
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To: Peter Zijlstra <peterz@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>, x86@kernel.org, hpa@zytor.com, Andy Lutomirski <luto@kernel.org>, Dave Hansen <dave.hansen@linux.intel.com>, Jiri Slaby <jslaby@suse.cz>, Dan Williams <dan.j.williams@intel.com>, Tom Lendacky <thomas.lendacky@amd.com>, Juergen Gross <jgross@suse.com>, Kees Cook <keescook@chromium.org>, David Rientjes <rientjes@google.com>, Cfir Cohen <cfir@google.com>, Erdem Aktas <erdemaktas@google.com>, Masami Hiramatsu <mhiramat@kernel.org>, Mike Stunes <mstunes@vmware.com>, Sean Christopherson <sean.j.christopherson@intel.com>, Martin Radev <martin.b.radev@gmail.com>, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org
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On Wed, Jul 15, 2020 at 12:13:10PM +0200, Peter Zijlstra wrote:
> On Wed, Jul 15, 2020 at 12:08:08PM +0200, Joerg Roedel wrote:
> > Right, but the handler calls into various other functions. I actually
> > started to annotate them all with noinstr, but that was a can of worms
> > when calling into generic kernel functions. And the only problem with
> > intrumentation in the #VC handler is the #VC-for-#DB exit-code, so I
> > decided to only handle this one with instrumentation forbidden and allow
> > it for the rest of the handler.
> 
> OK, then maybe change the comment to something like:
> 
>  /*
>   * Handle #DB before calling any !noinstr code to avoid
>   * recursive #DB.
>   */

Sounds good, will do.

Thanks,

	Joerg