Re: [Libguestfs] [PATCH libnbd] ublk: Add new nbdublk program

On Wed, Aug 31, 2022 at 06:33:25PM +0800, Ming Lei wrote: > On Wed, Aug 31, 2022 at 11:22:04AM +0100, Richard W.M. Jones wrote: > > > > After running those tests for an hour or two I got a nasty kernel > > memory corruption issue in the test VM, see attached. > > >From the dmesg log, the direct issue is from zram. > > The userspace ublksrv shouldn't trigger this kind of issue, and the only > related code is to discard IO pages if they are idle for enough time via > madvise(MADV_DONTNEED). > > In the ublk driver side, we just pin and unpin pages, and it shouldn't > be hard to verify if they work correctly . I will trace in that area. > Except for pin & unpin pages, ublk driver doesn't play any other mm > game. In case it's an unrelated bug in the very new RC2 kernel I've started another test which just uses a local (virtio-scsi) disk, to see if I observe the same thing or not.