Re: [PATCH 0/2] xen: fix two issues in Xen pv qspinlock handling

[Juergen Gross]

On 09/10/2018 16:40, David Woodhouse wrote:
> On Mon, 2018-10-01 at 09:16 +0200, Juergen Gross wrote:
>> The Xen specific queue spinlock wait function has two issues which
>> could result in a hanging system.
>>
>> They have a similar root cause of clearing a pending wakeup of a
>> waiting vcpu and later going to sleep waiting for the just cleared
>> wakeup event, which of course won't ever happen.
>>
>> Juergen Gross (2):
>>   xen: fix race in xen_qlock_wait()
>>   xen: make xen_qlock_wait() nestable
>>
>>  arch/x86/xen/spinlock.c | 33 ++++++++++++---------------------
>>  1 file changed, 12 insertions(+), 21 deletions(-)
>>
>> Cc: Waiman.Long@xxxxxx
>> Cc: peterz@xxxxxxxxxxxxx
> 
> LGTM. Both these should be Cc:stable@xxxxxxxxxxxxxxx, yes?

Yes, they are.

I have them already queued in the Xen tree. As the bug is rather
old I didn't want to rush the patches in so late in the rc phase of
4.19.


Juergen