Richard W.M. Jones
2022-Aug-31 10:22 UTC
[Libguestfs] [PATCH libnbd] ublk: Add new nbdublk program
After running those tests for an hour or two I got a nasty kernel memory corruption issue in the test VM, see attached. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com libguestfs lets you edit virtual machines. Supports shell scripting, bindings from many languages. http://libguestfs.org -------------- next part -------------- A non-text attachment was scrubbed... Name: dmesg.txt.gz Type: application/gzip Size: 11410 bytes Desc: not available URL: <http://listman.redhat.com/archives/libguestfs/attachments/20220831/8c464a81/attachment.gz>
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. thanks, Ming