diff mbox series

[Part2,RFC,v4,31/40] KVM: X86: update page-fault trace to log the 64-bit error code

Message ID 20210707183616.5620-32-brijesh.singh@amd.com (mailing list archive)
State New
Headers show
Series Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support | expand

Commit Message

Brijesh Singh July 7, 2021, 6:36 p.m. UTC 
The page-fault error code is a 64-bit value, but the trace prints only
the lower 32-bits. Some of the SEV-SNP RMP fault error codes are
available in the upper 32-bits.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
 arch/x86/kvm/trace.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Sean Christopherson July 16, 2021, 8:25 p.m. UTC | #1 
On Wed, Jul 07, 2021, Brijesh Singh wrote:
> The page-fault error code is a 64-bit value, but the trace prints only

It's worth clarifying that #NPT has a 64-bit error code, and so KVM also passes
around a 64-bit PFEC.  E.g. the above statement is wrong for legacy #PF.

> the lower 32-bits. Some of the SEV-SNP RMP fault error codes are
> available in the upper 32-bits.

Can you send this separately with Cc: stable@?  And I guess tweak the changelog
to replace "SEV-SNP RMP" with a reference to e.g. PFERR_GUEST_FINAL_MASK.  KVM
already has error codes that can set the upper bits.
Brijesh Singh July 17, 2021, 12:35 a.m. UTC | #2 
On 7/16/21 3:25 PM, Sean Christopherson wrote:
> On Wed, Jul 07, 2021, Brijesh Singh wrote:
>> The page-fault error code is a 64-bit value, but the trace prints only
> It's worth clarifying that #NPT has a 64-bit error code, and so KVM also passes
> around a 64-bit PFEC.  E.g. the above statement is wrong for legacy #PF.
>
>> the lower 32-bits. Some of the SEV-SNP RMP fault error codes are
>> available in the upper 32-bits.
> Can you send this separately with Cc: stable@?  And I guess tweak the changelog
> to replace "SEV-SNP RMP" with a reference to e.g. PFERR_GUEST_FINAL_MASK.  KVM
> already has error codes that can set the upper bits.

Will do.
diff mbox series

Patch

diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index a61c015870e3..78cbf53bf412 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -365,12 +365,12 @@  TRACE_EVENT(kvm_inj_exception,
  * Tracepoint for page fault.
  */
 TRACE_EVENT(kvm_page_fault,
-	TP_PROTO(unsigned long fault_address, unsigned int error_code),
+	TP_PROTO(unsigned long fault_address, u64 error_code),
 	TP_ARGS(fault_address, error_code),
 
 	TP_STRUCT__entry(
 		__field(	unsigned long,	fault_address	)
-		__field(	unsigned int,	error_code	)
+		__field(	u64,		error_code	)
 	),
 
 	TP_fast_assign(
@@ -378,7 +378,7 @@  TRACE_EVENT(kvm_page_fault,
 		__entry->error_code	= error_code;
 	),
 
-	TP_printk("address %lx error_code %x",
+	TP_printk("address %lx error_code %llx",
 		  __entry->fault_address, __entry->error_code)
 );