Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1625325 > unrolled thread

Re: [PATCH V4] x86: call smp vmxoff in smp stop

Started byPaolo Bonzini <pbonzini@redhat.com>
First post2017-04-18 15:40 +0200
Last post2017-04-19 12:00 +0200
Articles 4 — 2 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.


Contents

  Re: [PATCH V4] x86: call smp vmxoff in smp stop Paolo Bonzini <pbonzini@redhat.com> - 2017-04-18 15:40 +0200
    Re: [PATCH V4] x86: call smp vmxoff in smp stop Ingo Molnar <mingo@kernel.org> - 2017-04-19 10:10 +0200
      Re: [PATCH V4] x86: call smp vmxoff in smp stop Paolo Bonzini <pbonzini@redhat.com> - 2017-04-19 10:30 +0200
        Re: [PATCH V4] x86: call smp vmxoff in smp stop Ingo Molnar <mingo@kernel.org> - 2017-04-19 12:00 +0200

#1625325 — Re: [PATCH V4] x86: call smp vmxoff in smp stop

FromPaolo Bonzini <pbonzini@redhat.com>
Date2017-04-18 15:40 +0200
SubjectRe: [PATCH V4] x86: call smp vmxoff in smp stop
Message-ID<txBwl-6Is-1@gated-at.bofh.it>
Ingo, can you put this in tip?

Thanks,

Paolo

On 18/01/2017 12:32, Xishi Qiu wrote:
> From: Tiantian Feng <fengtiantian@huawei.com>
> 
> We need to disable VMX on all CPUs before stop cpu when OS panic,
> otherwisewe risk hanging up the machine, because the CPU ignore INIT
> signals when VMX is enabled. In kernel mainline this issue existence.
> 
> Signed-off-by: Tiantian Feng <fengtiantian@huawei.com>
> Signed-off-by: Xishi Qiu <qiuxishi@huawei.com>
> ---
>  arch/x86/kernel/smp.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
> index 68f8cc2..b574d55 100644
> --- a/arch/x86/kernel/smp.c
> +++ b/arch/x86/kernel/smp.c
> @@ -33,6 +33,7 @@
>  #include <asm/mce.h>
>  #include <asm/trace/irq_vectors.h>
>  #include <asm/kexec.h>
> +#include <asm/virtext.h>
>  
>  /*
>   *	Some notes on x86 processor bugs affecting SMP operation:
> @@ -162,6 +163,7 @@ static int smp_stop_nmi_callback(unsigned int val, struct pt_regs *regs)
>  	if (raw_smp_processor_id() == atomic_read(&stopping_cpu))
>  		return NMI_HANDLED;
>  
> +	cpu_emergency_vmxoff();
>  	stop_this_cpu(NULL);
>  
>  	return NMI_HANDLED;
> @@ -174,6 +176,7 @@ static int smp_stop_nmi_callback(unsigned int val, struct pt_regs *regs)
>  asmlinkage __visible void smp_reboot_interrupt(void)
>  {
>  	ipi_entering_ack_irq();
> +	cpu_emergency_vmxoff();
>  	stop_this_cpu(NULL);
>  	irq_exit();
>  }
> 

[toc] | [next] | [standalone]


#1625908

FromIngo Molnar <mingo@kernel.org>
Date2017-04-19 10:10 +0200
Message-ID<txSQy-YG-31@gated-at.bofh.it>
In reply to#1625325
* Paolo Bonzini <pbonzini@redhat.com> wrote:

> Ingo, can you put this in tip?
> 
> Thanks,
> 
> Paolo
> 
> On 18/01/2017 12:32, Xishi Qiu wrote:
> > From: Tiantian Feng <fengtiantian@huawei.com>
> > 
> > We need to disable VMX on all CPUs before stop cpu when OS panic,
> > otherwisewe risk hanging up the machine, because the CPU ignore INIT
> > signals when VMX is enabled. In kernel mainline this issue existence.

Yes, but the changelog is atrcious:

 - title should describe the purpose, not the implementation

 - CPU is spelled 'CPU' once, then 'cpu' _in the same sentence_!

 - typos

 - spelling

 - the last sentence doesn't even parse ...

Still it's already at V4 and comes with two signoffs and what amounts to a 
maintainer Ack??

Thanks,

	Ingo

[toc] | [prev] | [next] | [standalone]


#1625922

FromPaolo Bonzini <pbonzini@redhat.com>
Date2017-04-19 10:30 +0200
Message-ID<txT9U-15G-9@gated-at.bofh.it>
In reply to#1625908
> > On 18/01/2017 12:32, Xishi Qiu wrote:
> > > From: Tiantian Feng <fengtiantian@huawei.com>
> > > 
> > > We need to disable VMX on all CPUs before stop cpu when OS panic,
> > > otherwisewe risk hanging up the machine, because the CPU ignore INIT
> > > signals when VMX is enabled. In kernel mainline this issue existence.
> 
> Yes, but the changelog is atrcious:
> 
>  - title should describe the purpose, not the implementation
> 
>  - CPU is spelled 'CPU' once, then 'cpu' _in the same sentence_!
> 
>  - typos
> 
>  - spelling
> 
>  - the last sentence doesn't even parse ...
> 
> Still it's already at V4 and comes with two signoffs and what amounts to a
> maintainer Ack??

Well, the v2-v4 were really just about getting the signoffs right.  At some
point you just get desensitized about the changelog. :(

I'll post v5 with a rewritten commit message.

Paolo

[toc] | [prev] | [next] | [standalone]


#1625981

FromIngo Molnar <mingo@kernel.org>
Date2017-04-19 12:00 +0200
Message-ID<txUz1-1Rj-25@gated-at.bofh.it>
In reply to#1625922
* Paolo Bonzini <pbonzini@redhat.com> wrote:

> 
> > > On 18/01/2017 12:32, Xishi Qiu wrote:
> > > > From: Tiantian Feng <fengtiantian@huawei.com>
> > > > 
> > > > We need to disable VMX on all CPUs before stop cpu when OS panic,
> > > > otherwisewe risk hanging up the machine, because the CPU ignore INIT
> > > > signals when VMX is enabled. In kernel mainline this issue existence.
> > 
> > Yes, but the changelog is atrcious:
> > 
> >  - title should describe the purpose, not the implementation
> > 
> >  - CPU is spelled 'CPU' once, then 'cpu' _in the same sentence_!
> > 
> >  - typos
> > 
> >  - spelling
> > 
> >  - the last sentence doesn't even parse ...
> > 
> > Still it's already at V4 and comes with two signoffs and what amounts to a
> > maintainer Ack??
> 
> Well, the v2-v4 were really just about getting the signoffs right.  At some
> point you just get desensitized about the changelog. :(
> 
> I'll post v5 with a rewritten commit message.

Thanks!

	Ingo

[toc] | [prev] | [standalone]


Back to top | Article view | linux.kernel


csiph-web