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* [PATCH 2/2] kvm, MCE, Send SRAR SIGBUS directly
@ 2010-10-08  8:24 Huang Ying
  2010-10-08 20:25 ` Marcelo Tosatti
  0 siblings, 1 reply; 4+ messages in thread
From: Huang Ying @ 2010-10-08  8:24 UTC (permalink / raw)
  To: Avi Kivity, Marcelo Tosatti
  Cc: kvm@vger.kernel.org, Andi Kleen, linux-kernel@vger.kernel.org,
	Dean Nelson

Originally, SRAR SIGBUS is sent to QEMU-KVM via touching the poisoned
page. But commit 96054569190bdec375fe824e48ca1f4e3b53dd36 prevents the
signal from being sent. So now the signal is sent via
force_sig_info_fault directly.

Reported-by: Dean Nelson <dnelson@redhat.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
---
 arch/x86/include/asm/signal.h |    3 +++
 arch/x86/kvm/mmu.c            |   15 +++------------
 arch/x86/mm/fault.c           |    6 +++---
 3 files changed, 9 insertions(+), 15 deletions(-)

--- a/arch/x86/include/asm/signal.h
+++ b/arch/x86/include/asm/signal.h
@@ -258,6 +258,9 @@ struct pt_regs;
 
 #define ptrace_signal_deliver(regs, cookie) do { } while (0)
 
+void force_sig_info_fault(int si_signo, int si_code, unsigned long address,
+			  struct task_struct *tsk);
+
 #endif /* __KERNEL__ */
 #endif /* __ASSEMBLY__ */
 
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -158,9 +158,8 @@ is_prefetch(struct pt_regs *regs, unsign
 	return prefetch;
 }
 
-static void
-force_sig_info_fault(int si_signo, int si_code, unsigned long address,
-		     struct task_struct *tsk)
+void force_sig_info_fault(int si_signo, int si_code, unsigned long address,
+			  struct task_struct *tsk)
 {
 	siginfo_t info;
 
@@ -172,6 +171,7 @@ force_sig_info_fault(int si_signo, int s
 
 	force_sig_info(si_signo, &info, tsk);
 }
+EXPORT_SYMBOL_GPL(force_sig_info_fault);
 
 DEFINE_SPINLOCK(pgd_lock);
 LIST_HEAD(pgd_list);
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -39,6 +39,7 @@
 #include <asm/cmpxchg.h>
 #include <asm/io.h>
 #include <asm/vmx.h>
+#include <asm/signal.h>
 
 /*
  * When setting this variable to true it enables Two-Dimensional-Paging
@@ -2104,22 +2105,12 @@ static int __direct_map(struct kvm_vcpu
 	return pt_write;
 }
 
-static void kvm_send_hwpoison_signal(struct kvm *kvm, gfn_t gfn)
-{
-	char buf[1];
-	void __user *hva;
-	int r;
-
-	/* Touch the page, so send SIGBUS */
-	hva = (void __user *)gfn_to_hva(kvm, gfn);
-	r = copy_from_user(buf, hva, 1);
-}
-
 static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
 {
 	kvm_release_pfn_clean(pfn);
 	if (is_hwpoison_pfn(pfn)) {
-		kvm_send_hwpoison_signal(kvm, gfn);
+		force_sig_info_fault(SIGBUS, BUS_MCEERR_AR,
+				     gfn_to_hva(kvm, gfn), current);
 		return 0;
 	} else if (is_fault_pfn(pfn))
 		return -EFAULT;



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH 2/2] kvm, MCE, Send SRAR SIGBUS directly
  2010-10-08  8:24 [PATCH 2/2] kvm, MCE, Send SRAR SIGBUS directly Huang Ying
@ 2010-10-08 20:25 ` Marcelo Tosatti
  2010-10-09  0:37   ` Marcelo Tosatti
  2010-10-09  0:48   ` Huang Ying
  0 siblings, 2 replies; 4+ messages in thread
From: Marcelo Tosatti @ 2010-10-08 20:25 UTC (permalink / raw)
  To: Huang Ying
  Cc: Avi Kivity, kvm@vger.kernel.org, Andi Kleen,
	linux-kernel@vger.kernel.org, Dean Nelson

On Fri, Oct 08, 2010 at 04:24:15PM +0800, Huang Ying wrote:
> Originally, SRAR SIGBUS is sent to QEMU-KVM via touching the poisoned
> page. But commit 96054569190bdec375fe824e48ca1f4e3b53dd36 prevents the
> signal from being sent. So now the signal is sent via
> force_sig_info_fault directly.
> 
> Reported-by: Dean Nelson <dnelson@redhat.com>
> Signed-off-by: Huang Ying <ying.huang@intel.com>
> ---
>  arch/x86/include/asm/signal.h |    3 +++
>  arch/x86/kvm/mmu.c            |   15 +++------------
>  arch/x86/mm/fault.c           |    6 +++---
>  3 files changed, 9 insertions(+), 15 deletions(-)
> 
> --- a/arch/x86/include/asm/signal.h
> +++ b/arch/x86/include/asm/signal.h
> @@ -258,6 +258,9 @@ struct pt_regs;
>  
>  #define ptrace_signal_deliver(regs, cookie) do { } while (0)
>  
> +void force_sig_info_fault(int si_signo, int si_code, unsigned long address,
> +			  struct task_struct *tsk);
> +
>  #endif /* __KERNEL__ */
>  #endif /* __ASSEMBLY__ */
>  
> --- a/arch/x86/mm/fault.c
> +++ b/arch/x86/mm/fault.c
> @@ -158,9 +158,8 @@ is_prefetch(struct pt_regs *regs, unsign
>  	return prefetch;
>  }
>  
> -static void
> -force_sig_info_fault(int si_signo, int si_code, unsigned long address,
> -		     struct task_struct *tsk)
> +void force_sig_info_fault(int si_signo, int si_code, unsigned long address,
> +			  struct task_struct *tsk)
>  {
>  	siginfo_t info;
>  
> @@ -172,6 +171,7 @@ force_sig_info_fault(int si_signo, int s
>  
>  	force_sig_info(si_signo, &info, tsk);
>  }
> +EXPORT_SYMBOL_GPL(force_sig_info_fault);
>  
>  DEFINE_SPINLOCK(pgd_lock);
>  LIST_HEAD(pgd_list);
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -39,6 +39,7 @@
>  #include <asm/cmpxchg.h>
>  #include <asm/io.h>
>  #include <asm/vmx.h>
> +#include <asm/signal.h>
>  
>  /*
>   * When setting this variable to true it enables Two-Dimensional-Paging
> @@ -2104,22 +2105,12 @@ static int __direct_map(struct kvm_vcpu
>  	return pt_write;
>  }
>  
> -static void kvm_send_hwpoison_signal(struct kvm *kvm, gfn_t gfn)
> -{
> -	char buf[1];
> -	void __user *hva;
> -	int r;
> -
> -	/* Touch the page, so send SIGBUS */
> -	hva = (void __user *)gfn_to_hva(kvm, gfn);
> -	r = copy_from_user(buf, hva, 1);
> -}
> -
>  static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
>  {
>  	kvm_release_pfn_clean(pfn);
>  	if (is_hwpoison_pfn(pfn)) {
> -		kvm_send_hwpoison_signal(kvm, gfn);
> +		force_sig_info_fault(SIGBUS, BUS_MCEERR_AR,
> +				     gfn_to_hva(kvm, gfn), current);
>  		return 0;
>  	} else if (is_fault_pfn(pfn))
>  		return -EFAULT;

Better fill siginfo and use force_sig_info, which is already exported.

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH 2/2] kvm, MCE, Send SRAR SIGBUS directly
  2010-10-08 20:25 ` Marcelo Tosatti
@ 2010-10-09  0:37   ` Marcelo Tosatti
  2010-10-09  0:48   ` Huang Ying
  1 sibling, 0 replies; 4+ messages in thread
From: Marcelo Tosatti @ 2010-10-09  0:37 UTC (permalink / raw)
  To: Huang Ying
  Cc: Avi Kivity, kvm@vger.kernel.org, Andi Kleen,
	linux-kernel@vger.kernel.org, Dean Nelson

On Fri, Oct 08, 2010 at 05:25:01PM -0300, Marcelo Tosatti wrote:
> On Fri, Oct 08, 2010 at 04:24:15PM +0800, Huang Ying wrote:
> > Originally, SRAR SIGBUS is sent to QEMU-KVM via touching the poisoned
> > page. But commit 96054569190bdec375fe824e48ca1f4e3b53dd36 prevents the
> > signal from being sent. So now the signal is sent via
> > force_sig_info_fault directly.
> > 
> > Reported-by: Dean Nelson <dnelson@redhat.com>
> > Signed-off-by: Huang Ying <ying.huang@intel.com>
> > ---
> >  arch/x86/include/asm/signal.h |    3 +++
> >  arch/x86/kvm/mmu.c            |   15 +++------------
> >  arch/x86/mm/fault.c           |    6 +++---
> >  3 files changed, 9 insertions(+), 15 deletions(-)
> > 
> >  static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
> >  {
> >  	kvm_release_pfn_clean(pfn);
> >  	if (is_hwpoison_pfn(pfn)) {
> > -		kvm_send_hwpoison_signal(kvm, gfn);
> > +		force_sig_info_fault(SIGBUS, BUS_MCEERR_AR,
> > +				     gfn_to_hva(kvm, gfn), current);
> >  		return 0;
> >  	} else if (is_fault_pfn(pfn))
> >  		return -EFAULT;
> 
> Better fill siginfo and use force_sig_info, which is already exported.

Thats wrong, its not exported. But there is no need to force delivery,
so i've changed it to use send_sig_info.

Applied the other patches, thanks.


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH 2/2] kvm, MCE, Send SRAR SIGBUS directly
  2010-10-08 20:25 ` Marcelo Tosatti
  2010-10-09  0:37   ` Marcelo Tosatti
@ 2010-10-09  0:48   ` Huang Ying
  1 sibling, 0 replies; 4+ messages in thread
From: Huang Ying @ 2010-10-09  0:48 UTC (permalink / raw)
  To: Marcelo Tosatti
  Cc: Avi Kivity, kvm@vger.kernel.org, Andi Kleen,
	linux-kernel@vger.kernel.org, Dean Nelson

On Sat, 2010-10-09 at 04:25 +0800, Marcelo Tosatti wrote:
> On Fri, Oct 08, 2010 at 04:24:15PM +0800, Huang Ying wrote:
> > Originally, SRAR SIGBUS is sent to QEMU-KVM via touching the poisoned
> > page. But commit 96054569190bdec375fe824e48ca1f4e3b53dd36 prevents the
> > signal from being sent. So now the signal is sent via
> > force_sig_info_fault directly.
> > 
> > Reported-by: Dean Nelson <dnelson@redhat.com>
> > Signed-off-by: Huang Ying <ying.huang@intel.com>
> > ---
> >  arch/x86/include/asm/signal.h |    3 +++
> >  arch/x86/kvm/mmu.c            |   15 +++------------
> >  arch/x86/mm/fault.c           |    6 +++---
> >  3 files changed, 9 insertions(+), 15 deletions(-)
> > 
> > --- a/arch/x86/include/asm/signal.h
> > +++ b/arch/x86/include/asm/signal.h
> > @@ -258,6 +258,9 @@ struct pt_regs;
> >  
> >  #define ptrace_signal_deliver(regs, cookie) do { } while (0)
> >  
> > +void force_sig_info_fault(int si_signo, int si_code, unsigned long address,
> > +			  struct task_struct *tsk);
> > +
> >  #endif /* __KERNEL__ */
> >  #endif /* __ASSEMBLY__ */
> >  
> > --- a/arch/x86/mm/fault.c
> > +++ b/arch/x86/mm/fault.c
> > @@ -158,9 +158,8 @@ is_prefetch(struct pt_regs *regs, unsign
> >  	return prefetch;
> >  }
> >  
> > -static void
> > -force_sig_info_fault(int si_signo, int si_code, unsigned long address,
> > -		     struct task_struct *tsk)
> > +void force_sig_info_fault(int si_signo, int si_code, unsigned long address,
> > +			  struct task_struct *tsk)
> >  {
> >  	siginfo_t info;
> >  
> > @@ -172,6 +171,7 @@ force_sig_info_fault(int si_signo, int s
> >  
> >  	force_sig_info(si_signo, &info, tsk);
> >  }
> > +EXPORT_SYMBOL_GPL(force_sig_info_fault);
> >  
> >  DEFINE_SPINLOCK(pgd_lock);
> >  LIST_HEAD(pgd_list);
> > --- a/arch/x86/kvm/mmu.c
> > +++ b/arch/x86/kvm/mmu.c
> > @@ -39,6 +39,7 @@
> >  #include <asm/cmpxchg.h>
> >  #include <asm/io.h>
> >  #include <asm/vmx.h>
> > +#include <asm/signal.h>
> >  
> >  /*
> >   * When setting this variable to true it enables Two-Dimensional-Paging
> > @@ -2104,22 +2105,12 @@ static int __direct_map(struct kvm_vcpu
> >  	return pt_write;
> >  }
> >  
> > -static void kvm_send_hwpoison_signal(struct kvm *kvm, gfn_t gfn)
> > -{
> > -	char buf[1];
> > -	void __user *hva;
> > -	int r;
> > -
> > -	/* Touch the page, so send SIGBUS */
> > -	hva = (void __user *)gfn_to_hva(kvm, gfn);
> > -	r = copy_from_user(buf, hva, 1);
> > -}
> > -
> >  static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
> >  {
> >  	kvm_release_pfn_clean(pfn);
> >  	if (is_hwpoison_pfn(pfn)) {
> > -		kvm_send_hwpoison_signal(kvm, gfn);
> > +		force_sig_info_fault(SIGBUS, BUS_MCEERR_AR,
> > +				     gfn_to_hva(kvm, gfn), current);
> >  		return 0;
> >  	} else if (is_fault_pfn(pfn))
> >  		return -EFAULT;
> 
> Better fill siginfo and use force_sig_info, which is already exported.

It seems that force_sig_info is not exported for now.

Best Regards,
Huang Ying



^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2010-10-09  1:05 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2010-10-08  8:24 [PATCH 2/2] kvm, MCE, Send SRAR SIGBUS directly Huang Ying
2010-10-08 20:25 ` Marcelo Tosatti
2010-10-09  0:37   ` Marcelo Tosatti
2010-10-09  0:48   ` Huang Ying

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