RE: [PATCH V3 3/6] x86/Hyper-V: Trigger crash enlightenment only once during system crash.

[Michael Kelley]

From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx> Sent: Tuesday, March 24, 2020 12:57 AM
> 
> When a guest VM panics, Hyper-V should be notified only once via the
> crash synthetic MSRs.  Current Linux code might write these crash MSRs
> twice during a system panic:
> 1) hyperv_panic/die_event() calling hyperv_report_panic()
> 2) hv_kmsg_dump() calling hyperv_report_panic_msg()
> 
> Fix this by not calling hyperv_report_panic() if a kmsg dump has been
> successfully registered.  The notification will happen later via
> hyperv_report_panic_msg().
> 
> Signed-off-by: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
> ---
> Change since v1:
> 	- Update commit log
> 
> Change since v2:
>         - Update comment
> ---
>  drivers/hv/vmbus_drv.c | 16 ++++++++++++++--
>  1 file changed, 14 insertions(+), 2 deletions(-)
> 

Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>