From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [PATCH v4 2/5] x86/msr: Carry on after a non-"safe" MSR access fails without !panic_on_oops Date: Mon, 14 Mar 2016 10:11:39 -0700 Message-ID: References: <20160314120202.GD15800@pd.tnic> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============3026936938807382291==" Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" To: Andy Lutomirski Cc: KVM list , Peter Zijlstra , X86 ML , "linux-kernel@vger.kernel.org" , xen-devel , Borislav Petkov , Andy Lutomirski , Paolo Bonzini , Andrew Morton , Arjan van de Ven List-Id: xen-devel@lists.xenproject.org --===============3026936938807382291== Content-Type: multipart/alternative; boundary=001a113fb632bf5dfb052e055fcc --001a113fb632bf5dfb052e055fcc Content-Type: text/plain; charset=UTF-8 On Mar 14, 2016 10:05 AM, "Andy Lutomirski" wrote: > > We could probably remove that check and let custom fixups run early. > I don't see any compelling reason to keep them disabled. That should > probably be a separate change, though. Or we could just use the existing wrmsr_safe() code and not add this new special code at all. Look, why are you doing this? We should get rid of the difference between wrmsr and wrmsr_safe(), not make it bigger. Just make everything safe. There has never in the history of anything been an advantage to making things oops and to making things more complicated. Why is rd/wrmsr() so magically important? Linus --001a113fb632bf5dfb052e055fcc Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


On Mar 14, 2016 10:05 AM, "Andy Lutomirski" <luto@amacapital.net> wrote:
>
> We could probably remove that check and let custom fixups run early. > I don't see any compelling reason to keep them disabled.=C2=A0 Tha= t should
> probably be a separate change, though.

Or we could just use the existing wrmsr_safe() code and not = add this new special code at all.

Look, why are you doing this? We should get rid of the diffe= rence between wrmsr and wrmsr_safe(), not make it bigger.

Just make everything safe. There has never in the history of= anything been an advantage to making things oops and to making things more= complicated.

Why is rd/wrmsr() so magically important?

=C2=A0=C2=A0=C2=A0 Linus

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