lkml.org 
[lkml]   [2018]   [Aug]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH net] vhost: correctly check the iova range when waking virtqueue
On Fri, Aug 24, 2018 at 04:53:13PM +0800, Jason Wang wrote:
> We don't wakeup the virtqueue if the first byte of pending iova range
> is the last byte of the range we just got updated. This will lead a
> virtqueue to wait for IOTLB updating forever. Fixing by correct the
> check and wake up the virtqueue in this case.
>
> Fixes: 6b1e6cc7855b ("vhost: new device IOTLB API")
> Reported-by: Peter Xu <peterx@redhat.com>
> Signed-off-by: Jason Wang <jasowang@redhat.com>

Without this patch, this command will trigger the IO hang merely every
time from host to guest:

netperf -H 1.2.3.4 -l 5 -t TCP_RR -- -b 100

After applying, I can run it 10 times continuously without a problem.

Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>

Thanks,

--
Peter Xu

\
 
 \ /
  Last update: 2018-08-24 11:37    [W:0.036 / U:0.884 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site