On Sat, Jul 4, 2020 at 1:38 PM David P. Reed <dpr...@deepplum.com> wrote: > > Fix: Mask undefined operation fault during emergency VMXOFF that must be > attempted to force cpu exit from VMX root operation. > Explanation: When a cpu may be in VMX root operation (only possible when > CR4.VMXE is set), crash or panic reboot tries to exit VMX root operation > using VMXOFF. This is necessary, because any INIT will be masked while cpu > is in VMX root operation, but that state cannot be reliably > discerned by the state of the cpu. > VMXOFF faults if the cpu is not actually in VMX root operation, signalling > undefined operation. > Discovered while debugging an out-of-tree x-visor with a race. Can happen > due to certain kinds of bugs in KVM.
Can you re-wrap lines to 68 characters? Also, the Fix: and Explanation: is probably unnecessary. You could say: Ignore a potential #UD failut during emergency VMXOFF ... When a cpu may be in VMX ... > > Fixes: 208067 <https://bugzilla.kernel.org/show_bug.cgi?id=208067> > Reported-by: David P. Reed <dpr...@deepplum.com> It's not really necessary to say that you, the author, reported the problem, but I guess it's harmless. > Suggested-by: Thomas Gleixner <t...@linutronix.de> > Suggested-by: Sean Christopherson <sean.j.christopher...@intel.com> > Suggested-by: Andy Lutomirski <l...@kernel.org> > Signed-off-by: David P. Reed <dpr...@deepplum.com> > --- > arch/x86/include/asm/virtext.h | 20 ++++++++++++++------ > 1 file changed, 14 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h > index 0ede8d04535a..0e0900eacb9c 100644 > --- a/arch/x86/include/asm/virtext.h > +++ b/arch/x86/include/asm/virtext.h > @@ -30,11 +30,11 @@ static inline int cpu_has_vmx(void) > } > > > -/* Disable VMX on the current CPU > +/* Exit VMX root mode and isable VMX on the current CPU. s/isable/disable/ > /* Disable VMX if it is supported and enabled on the current CPU > -- > 2.26.2 > Other than that: Reviewed-by: Andy Lutomirski <l...@kernel.org> --Andy
