On 2/24/23 3:48 PM, Heming Zhao via Ocfs2-devel wrote:> On 2/24/23 2:54 PM, Joseph Qi wrote: >> I can reproduce this in my local VM. >> I've traced ocfs2_dismount_volume and found that it hasn't been called. >> So EBUSY is returned in VFS layer. I guess something wrong when doing >> a copy with linked SQEs (normal copy seems no problem). >> > > I am inclined to agree with you. I also test liburing examples apps > on ext4 partition, everything looks fine. > > I used below bpftrace method, the retval is '3'. > ?bpftrace -e 'kr:mnt_get_count{printf("%d\n", retval);}' > > It responds to flow: path_umount() => do_umount => mnt_get_count (gets '3') >Yes, that's the place return EBUSY. So the problem seems to be getmnt/putmnt not match in this case. Thanks, Joseph> >> >> On 2/24/23 8:32 AM, Heming Zhao wrote: >>> Hello List, >>> >>> I found a weird bug on ocfs2. I am busying with other jobs, if anyone have time >>> he/she could fix it. This bug is blocking fstest generic/013 test case, and also >>> blocking fstest to do later test cases. >>> >>> How to trigger: >>> ``` >>> git clone git://git.kernel.dk/liburing.git >>> cd liburing >>> make >>> cd examples >>> mount -t ocfs2 /dev/sda /mnt >>> cp /etc/hosts /mnt/a >>> ./link-cp /mnt/a /mnt/b >>> umount /mnt >>> ``` >>> >>> umount trigger error message: >>> ``` >>> # umount /mnt >>> umount: /mnt: target is busy. >>> ``` >>> >>> The umount error can only be triggered by liburing write operation. >>> >>> Thanks, >>> Heming > > > _______________________________________________ > Ocfs2-devel mailing list > Ocfs2-devel at oss.oracle.com > https://oss.oracle.com/mailman/listinfo/ocfs2-devel
Heming Zhao
2023-Feb-24 08:03 UTC
[Ocfs2-devel] report BUG: io_uring triggers umount error
On 2/24/23 3:52 PM, Joseph Qi wrote:> > > On 2/24/23 3:48 PM, Heming Zhao via Ocfs2-devel wrote: >> On 2/24/23 2:54 PM, Joseph Qi wrote: >>> I can reproduce this in my local VM. >>> I've traced ocfs2_dismount_volume and found that it hasn't been called. >>> So EBUSY is returned in VFS layer. I guess something wrong when doing >>> a copy with linked SQEs (normal copy seems no problem). >>> >> >> I am inclined to agree with you. I also test liburing examples apps >> on ext4 partition, everything looks fine. >> >> I used below bpftrace method, the retval is '3'. >> ?bpftrace -e 'kr:mnt_get_count{printf("%d\n", retval);}' >> >> It responds to flow: path_umount() => do_umount => mnt_get_count (gets '3') >> > Yes, that's the place return EBUSY. > So the problem seems to be getmnt/putmnt not match in this case. >I didn't familiar with setting up kernel bi-search env. I used one last year openSUSE tumblweed (with kernel 5.16.2), this umount issue doesn't exist. So there is a possibility one ocfs2 commit introduced this issue. Thanks, Heming> >> >>> >>> On 2/24/23 8:32 AM, Heming Zhao wrote: >>>> Hello List, >>>> >>>> I found a weird bug on ocfs2. I am busying with other jobs, if anyone have time >>>> he/she could fix it. This bug is blocking fstest generic/013 test case, and also >>>> blocking fstest to do later test cases. >>>> >>>> How to trigger: >>>> ``` >>>> git clone git://git.kernel.dk/liburing.git >>>> cd liburing >>>> make >>>> cd examples >>>> mount -t ocfs2 /dev/sda /mnt >>>> cp /etc/hosts /mnt/a >>>> ./link-cp /mnt/a /mnt/b >>>> umount /mnt >>>> ``` >>>> >>>> umount trigger error message: >>>> ``` >>>> # umount /mnt >>>> umount: /mnt: target is busy. >>>> ``` >>>> >>>> The umount error can only be triggered by liburing write operation. >>>> >>>> Thanks, >>>> Heming >> >> >> _______________________________________________ >> Ocfs2-devel mailing list >> Ocfs2-devel at oss.oracle.com >> https://oss.oracle.com/mailman/listinfo/ocfs2-devel