Re: [PATCH Part2 v6 33/49] KVM: x86: Update page-fault trace to log full 64-bit error code

From: Vlastimil Babka
Date: Mon Jul 25 2022 - 07:19:35 EST


On 6/21/22 01:10, Ashish Kalra wrote:
> From: Brijesh Singh <brijesh.singh@xxxxxxx>
>
> The #NPT error code is a 64-bit value but the trace prints only the
> lower 32-bits. Some of the fault error code (e.g PFERR_GUEST_FINAL_MASK)
> are available in the upper 32-bits.
>
> Cc: <stable@xxxxxxxxxx>

Why stable?

> Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
> ---
> arch/x86/kvm/trace.h | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
> index e3a24b8f04be..9b9bc5468103 100644
> --- a/arch/x86/kvm/trace.h
> +++ b/arch/x86/kvm/trace.h
> @@ -383,12 +383,12 @@ 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(
> @@ -396,7 +396,7 @@ 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)
> );
>