linux-kernel - Re: [PATCH] x86/kernel/cpu/amd.c: don't apply the lahf

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Message-ID: <alpine.LRH.2.02.1707210730210.13570@file01.intranet.prod.int.rdu2.redhat.com>
Date:   Fri, 21 Jul 2017 07:34:59 -0400 (EDT)
From:   Mikulas Patocka <mpatocka@...hat.com>
To:     Borislav Petkov <bp@...en8.de>
cc:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H. Peter Anvin" <hpa@...or.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org, kvm-ML <kvm@...r.kernel.org>
Subject: Re: [PATCH] x86/kernel/cpu/amd.c: don't apply the lahf_lm workaround
 in a hypervisor



On Thu, 13 Jul 2017, Borislav Petkov wrote:

> On Wed, Jul 12, 2017 at 10:27:44PM -0400, Mikulas Patocka wrote:
> > It is not strictly needed, but it is annoying. I work in the console and 
> > it is annoying to see these "unhandled rdmsr" messages printed over the 
> > screen every time I reboot a virtual machine.
> 
> Those messages are already pr_debug_ratelimited(). Fix your loglevel to
> not see them.

The message 'unhandled rdmsr' is printed with "pr_err_ratelimited" in the 
kernels up to and including 4.9. So it can't be easily silenced, silencing 
it silences any errors.

(and I can't use kernels newer that 4.4 on the host machine because of 
broken hibernation)

Mikulas

> -- 
> Regards/Gruss,
>     Boris.
> 
> ECO tip #101: Trim your mails when you reply.
> --