在 2022/10/24 13:31, Dave Chinner 写道: > On Mon, Oct 24, 2022 at 03:17:52AM +0000, ruansy.fnst@xxxxxxxxxxx wrote: >> 在 2022/10/24 6:00, Dave Chinner 写道: >>> On Fri, Oct 21, 2022 at 07:11:02PM -0700, Darrick J. Wong wrote: >>>> On Thu, Oct 20, 2022 at 10:17:45PM +0800, Yang, Xiao/杨 晓 wrote: >>>>> In addition, I don't like your idea about the test change because it will >>>>> make generic/470 become the special test for XFS. Do you know if we can fix >>>>> the issue by changing the test in another way? blkdiscard -z can fix the >>>>> issue because it does zero-fill rather than discard on the block device. >>>>> However, blkdiscard -z will take a lot of time when the block device is >>>>> large. >>>> >>>> Well we /could/ just do that too, but that will suck if you have 2TB of >>>> pmem. ;) >>>> >>>> Maybe as an alternative path we could just create a very small >>>> filesystem on the pmem and then blkdiscard -z it? >>>> >>>> That said -- does persistent memory actually have a future? Intel >>>> scuttled the entire Optane product, cxl.mem sounds like expansion >>>> chassis full of DRAM, and fsdax is horribly broken in 6.0 (weird kernel >>>> asserts everywhere) and 6.1 (every time I run fstests now I see massive >>>> data corruption). >>> >>> Yup, I see the same thing. fsdax was a train wreck in 6.0 - broken >>> on both ext4 and XFS. Now that I run a quick check on 6.1-rc1, I >>> don't think that has changed at all - I still see lots of kernel >>> warnings, data corruption and "XFS_IOC_CLONE_RANGE: Invalid >>> argument" errors. >> >> Firstly, I think the "XFS_IOC_CLONE_RANGE: Invalid argument" error is >> caused by the restrictions which prevent reflink work together with DAX: >> >> a. fs/xfs/xfs_ioctl.c:1141 >> /* Don't allow us to set DAX mode for a reflinked file for now. */ >> if ((fa->fsx_xflags & FS_XFLAG_DAX) && xfs_is_reflink_inode(ip)) >> return -EINVAL; >> >> b. fs/xfs/xfs_iops.c:1174 >> /* Only supported on non-reflinked files. */ >> if (xfs_is_reflink_inode(ip)) >> return false; >> >> These restrictions were removed in "drop experimental warning" patch[1]. >> I think they should be separated from that patch. >> >> [1] >> https://lore.kernel.org/linux-xfs/1663234002-17-1-git-send-email-ruansy.fnst@xxxxxxxxxxx/ >> >> >> Secondly, how the data corruption happened? > > No idea - i"m just reporting that lots of fsx tests failed with data > corruptions. I haven't had time to look at why, I'm still trying to > sort out the fix for a different data corruption... > >> Or which case failed? > > *lots* of them failed with kernel warnings with reflink turned off: > > SECTION -- xfs_dax_noreflink > ========================= > Failures: generic/051 generic/068 generic/075 generic/083 > generic/112 generic/127 generic/198 generic/231 generic/247 > generic/269 generic/270 generic/340 generic/344 generic/388 > generic/461 generic/471 generic/476 generic/519 generic/561 xfs/011 > xfs/013 xfs/073 xfs/297 xfs/305 xfs/517 xfs/538 > Failed 26 of 1079 tests > > All of those except xfs/073 and generic/471 are failures due to > warnings found in dmesg. > > With reflink enabled, I terminated the run after g/075, g/091, g/112 > and generic/127 reported fsx data corruptions and g/051, g/068, > g/075 and g/083 had reported kernel warnings in dmesg. > >> Could >> you give me more info (such as mkfs options, xfstests configs)? > > They are exactly the same as last time I reported these problems. > > For the "no reflink" test issues: > > mkfs options are "-m reflink=0,rmapbt=1", mount options "-o > dax=always" for both filesytems. Config output at start of test > run: > > SECTION -- xfs_dax_noreflink > FSTYP -- xfs (debug) > PLATFORM -- Linux/x86_64 test3 6.1.0-rc1-dgc+ #1615 SMP PREEMPT_DYNAMIC Wed Oct 19 12:24:16 AEDT 2022 > MKFS_OPTIONS -- -f -m reflink=0,rmapbt=1 /dev/pmem1 > MOUNT_OPTIONS -- -o dax=always -o context=system_u:object_r:root_t:s0 /dev/pmem1 /mnt/scratch > > pmem devices are a pair of fake 8GB pmem regions set up by kernel > CLI via "memmap=8G!15G,8G!24G". I don't have anything special set up > - the kernel config is kept minimal for these VMs - and the only > kernel debug option I have turned on for these specific test runs is > CONFIG_XFS_DEBUG=y. Thanks for the detailed info. But, in my environment (and my colleagues', and our real server with DCPMM) these failure cases (you mentioned above, in dax+non_reflink mode, with same test options) cannot reproduce. Here's our test environment info: - Ruan's env: fedora 36(v6.0-rc1) on kvm,pmem 2x4G:file backended - Yang's env: fedora 35(v6.1-rc1) on kvm,pmem 2x1G:memmap=1G!1G,1G!2G - Server's : Ubuntu 20.04(v6.0-rc1) real machine,pmem 2x4G:real DCPMM (To quickly confirm the difference, I just ran the failed 26 cases you mentioned above.) Except for generic/471 and generic/519, which failed even when dax is off, the rest passed. We don't want fsdax to be truned off. Right now, I think the most important thing is solving the failed cases in dax+non_reflink mode. So, firstly, I have to reproduce those failures. Is there any thing wrong with my test environments? I konw you are using 'memmap=XXG!YYG' to simulate pmem. So, (to Darrick) could you show me your config of dev environment and the 'testcloud'(I am guessing it's a server with real nvdimm just like ours)? (I just found I only tested on 4G and smaller pmem device. I'll try the test on 8G pmem) > > THe only difference between the noreflink and reflink runs is that I > drop the "-m reflink=0" mkfs parameter. Otherwise they are identical > and the errors I reported are from back-to-back fstests runs without > rebooting the VM.... > > -Dave. -- Thanks, Ruan.
