Re: LTP rwtest01 blocks on DAX mountpoint

From: Xiong Zhou
Date: Tue Jan 03 2017 - 20:21:48 EST


On Tue, Jan 03, 2017 at 09:57:10AM -0700, Ross Zwisler wrote:
> On Tue, Jan 03, 2017 at 02:49:22PM +0800, Xiong Zhou wrote:
> > On Mon, Jan 02, 2017 at 02:49:41PM -0700, Ross Zwisler wrote:
> > > On Mon, Jan 02, 2017 at 06:16:17PM +0100, Jan Kara wrote:
> > > > On Fri 30-12-16 17:33:53, Xiong Zhou wrote:
> > > > > On Sat, Dec 24, 2016 at 07:07:14PM +0800, Xiong Zhou wrote:
> > > > > > Hi lists,
> > snip
> > > > I was trying to reproduce this but for me rwtest01 completes just fine on
> > > > dax mountpoint (I've used your reproducer). So can you sample several
> > > > kernel stack traces to get a rough idea where the kernel is running?
> > > > Thanks!
> > > >
> > > > Honza
> > >
> > > I'm also unable to reproduce this issue. I've tried with both the blamed
> > > commit:
> > > 4b4bb46 (HEAD) dax: clear dirty entry tags on cache flush
> > > and with v4.9-rc2. Both pass the test in my setup.
> > > Perhaps the variable is the size of your PMEM partitions?
> > > # fdisk -l /dev/pmem0
> > > Disk /dev/pmem0: 16 GiB, 17179869184 bytes, 33554432 sectors
> > > Units: sectors of 1 * 512 = 512 bytes
> > > Sector size (logical/physical): 512 bytes / 4096 bytes
> > > I/O size (minimum/optimal): 4096 bytes / 4096 bytes
> > > Disklabel type: dos
> > > Disk identifier: 0xfe50c900
> > > Device Boot Start End Sectors Size Id Type
> > > /dev/pmem0p1 4096 25165823 25161728 12G 83 Linux
> > > /dev/pmem0p2 25165824 33550335 8384512 4G 83 Linux
> > >
> > > What does your setup look like?
> > > I'm using the current tip of the LTP tree:
> > > 8cc4165 waitid02: define _XOPEN_SOURCE 500
> > > Thanks,
> > > - Ross
> >
> > Thanks all for looking into it.
> >
> > Turns out the rc2 relative updates fix this issue, so does
> > an old issue i reported a while ago:
> > multi-threads libvmmalloc fork test hang
> > https://lists.01.org/pipermail/linux-nvdimm/2016-October/007602.html
> >
> > I'm able to reproduce these issues before rc2, now it
> > passes on current Linus tree:
> > c8b4ec8 Merge tag 'fscrypt-for-stable'
>
> Hmm...I'm able to reproduce the other libvmmalloc issue with both v4.10-rc2
> and with "c8b4ec8 Merge tag 'fscrypt-for-stable'". I'm debugging that issue
> today.
>
> It's interesting that both tests started passing for you. Did you change
> something in your test setup?

Nope.