Re: [PATCH] KVM: SVM: Only dump VSMA to klog for debugging

[Peter Gonda]

On Thu, Nov 3, 2022 at 4:25 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote:
>
> On Thu, Nov 03, 2022, Peter Gonda wrote:
> > The KERN_CONT documentation says it defaults back to KERNL_DEFAULT if the
>
> State what actually happens.  Documentation is sometimes wrong, and just saying
> "the docs say XYZ" makes it sound like this is a fix based on code inspection,
> whereas you encountered a real problem.  E.g.
>
>   Explicitly print the VMSA dump at KERN_DEBUG log level, KERN_CONT uses
>   KERNEL_DEFAULT if the previous log line has a newline, i.e. if there's
>   nothing to continuing, and as a result the VMSA gets dumped when it
>   shouldn't.
>
> > previous log line has a newline. So switch from KERN_CONT to
> > print_hex_dump_debug().
>
> Jarkko pointed this out in the original submission, but the buggy patch got queued
> without the fixup.  This is a good opportunity to throw in a link so that it's
> clear that the change is aligned with the original intent.
>
>   Link: https://lore.kernel.org/all/YuPMeWX4uuR1Tz3M@xxxxxxxxxx

Thanks. I've expanded on the description based on your feedback.

>
> > Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
> > Cc: Harald Hoyer <harald@xxxxxxxxxxx>
> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> > Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: Borislav Petkov <bp@xxxxxxxxx>
> > Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> > Cc: x86@xxxxxxxxxx
> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> > Cc: kvm@xxxxxxxxxxxxxxx
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
> > Signed-off-by: Peter Gonda <pgonda@xxxxxxxxxx>
> >
> > Fixes: 6fac42f127b8 ("KVM: SVM: Dump Virtual Machine Save Area (VMSA) to klog")
>
> Fixes: usually goes before everything else, and this should probably Cc stable@
> as well.
>
> With the above tweaks,
>
> Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>

Done. Sent a V2 with your review tag.