| Message ID | 20200409112900.15341-1-amir73il@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | overlay/029: fix test failure with index feature enabled | expand |
On Thu, Apr 09, 2020 at 02:29:00PM +0300, Amir Goldstein wrote: > When overlayfs index feature is enabled by default in either kernel > config or module parameters, this test fails: > > mount: /tmp/8751/mnt: mount(2) system call failed: Stale file handle. > cat: /tmp/8751/mnt/bar: No such file or directory > > The reason is that with index feature enabled, an upper/work dirs cannot > be reused for mounting with a different lower layer. I re-built my test kernel with CONFIG_OVERLAY_FS_INDEX=y, and confirmed /sys/module/overlay/parameters/index is 'Y', but test still passes for me. And I do notice the following info in dmesg: [ 598.663923] overlayfs: fs on '/mnt/scratch/ovl-mnt/up' does not support file handles, falling back to index=off,nfs_export=off. [ 598.674299] overlayfs: fs on '/mnt/scratch/ovl-mnt/low' does not support file handles, falling back to index=off,nfs_export=off. [ 598.684594] overlayfs: fs on '/mnt/scratch/ovl-mnt/' does not support file handles, falling back to index=off,nfs_export=off. Seems it has something to do with nfs_export feature? I have it disabled by default. # CONFIG_OVERLAY_FS_NFS_EXPORT is not set Could you please help confirm? Thanks, Eryu > > Reported-by: Chengguang Xu <cgxu519@mykernel.net> > Signed-off-by: Amir Goldstein <amir73il@gmail.com> > --- > tests/overlay/029 | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/tests/overlay/029 b/tests/overlay/029 > index 1d2d2092..17f58de7 100755 > --- a/tests/overlay/029 > +++ b/tests/overlay/029 > @@ -68,12 +68,18 @@ _overlay_mount_dirs $SCRATCH_MNT/up $tmp/{upper,work} \ > cat $tmp/mnt/foo > $UMOUNT_PROG $tmp/mnt > > +# re-create upper/work to avoid ovl_verify_origin() mount failure > +# when index is enabled > +rm -rf $tmp/{upper,work} > +mkdir -p $tmp/{upper,work} > # mount overlay again using lower dir from SCRATCH_MNT dir > _overlay_mount_dirs $SCRATCH_MNT/low $tmp/{upper,work} \ > overlay $tmp/mnt > cat $tmp/mnt/bar > $UMOUNT_PROG $tmp/mnt > > +rm -rf $tmp/{upper,work} > +mkdir -p $tmp/{upper,work} > # mount overlay again using SCRATCH_MNT dir > _overlay_mount_dirs $SCRATCH_MNT/ $tmp/{upper,work} \ > overlay $tmp/mnt > -- > 2.17.1 >
On Sun, Apr 19, 2020 at 7:05 PM Eryu Guan <guan@eryu.me> wrote: > > On Thu, Apr 09, 2020 at 02:29:00PM +0300, Amir Goldstein wrote: > > When overlayfs index feature is enabled by default in either kernel > > config or module parameters, this test fails: > > > > mount: /tmp/8751/mnt: mount(2) system call failed: Stale file handle. > > cat: /tmp/8751/mnt/bar: No such file or directory > > > > The reason is that with index feature enabled, an upper/work dirs cannot > > be reused for mounting with a different lower layer. > > I re-built my test kernel with CONFIG_OVERLAY_FS_INDEX=y, and confirmed > /sys/module/overlay/parameters/index is 'Y', but test still passes for > me. And I do notice the following info in dmesg: > > [ 598.663923] overlayfs: fs on '/mnt/scratch/ovl-mnt/up' does not support file handles, falling back to index=off,nfs_export=off. > [ 598.674299] overlayfs: fs on '/mnt/scratch/ovl-mnt/low' does not support file handles, falling back to index=off,nfs_export=off. > [ 598.684594] overlayfs: fs on '/mnt/scratch/ovl-mnt/' does not support file handles, falling back to index=off,nfs_export=off. > > Seems it has something to do with nfs_export feature? I have it disabled > by default. > > # CONFIG_OVERLAY_FS_NFS_EXPORT is not set > > Could you please help confirm? > I confirm. enabling index on nested overlay requires that the lower overlay has nfs_export enabled. Missed that, but in the bug report, CONFIG_OVERLAY_FS_NFS_EXPORT was indeed set. You do not need to rebuild the kernel. You can reproduce the failure by setting overlay module parameter before running the tests. echo Y > /sys/module/overlay/parameters/index echo Y > /sys/module/overlay/parameters/nfs_export Thanks, Amir.
On Sun, Apr 19, 2020 at 07:12:33PM +0300, Amir Goldstein wrote: > On Sun, Apr 19, 2020 at 7:05 PM Eryu Guan <guan@eryu.me> wrote: > > > > On Thu, Apr 09, 2020 at 02:29:00PM +0300, Amir Goldstein wrote: > > > When overlayfs index feature is enabled by default in either kernel > > > config or module parameters, this test fails: > > > > > > mount: /tmp/8751/mnt: mount(2) system call failed: Stale file handle. > > > cat: /tmp/8751/mnt/bar: No such file or directory > > > > > > The reason is that with index feature enabled, an upper/work dirs cannot > > > be reused for mounting with a different lower layer. > > > > I re-built my test kernel with CONFIG_OVERLAY_FS_INDEX=y, and confirmed > > /sys/module/overlay/parameters/index is 'Y', but test still passes for > > me. And I do notice the following info in dmesg: > > > > [ 598.663923] overlayfs: fs on '/mnt/scratch/ovl-mnt/up' does not support file handles, falling back to index=off,nfs_export=off. > > [ 598.674299] overlayfs: fs on '/mnt/scratch/ovl-mnt/low' does not support file handles, falling back to index=off,nfs_export=off. > > [ 598.684594] overlayfs: fs on '/mnt/scratch/ovl-mnt/' does not support file handles, falling back to index=off,nfs_export=off. > > > > Seems it has something to do with nfs_export feature? I have it disabled > > by default. > > > > # CONFIG_OVERLAY_FS_NFS_EXPORT is not set > > > > Could you please help confirm? > > > > I confirm. enabling index on nested overlay requires that > the lower overlay has nfs_export enabled. Thanks! > > Missed that, but in the bug report, CONFIG_OVERLAY_FS_NFS_EXPORT > was indeed set. Would you please update the commit log accordingly as well? > > You do not need to rebuild the kernel. > You can reproduce the failure by setting overlay module parameter before > running the tests. > > echo Y > /sys/module/overlay/parameters/index > echo Y > /sys/module/overlay/parameters/nfs_export Ah, forgot about that.. it's easier now :) Thanks, Eryu
On Sun, Apr 19, 2020 at 8:00 PM Eryu Guan <guan@eryu.me> wrote: > > On Sun, Apr 19, 2020 at 07:12:33PM +0300, Amir Goldstein wrote: > > On Sun, Apr 19, 2020 at 7:05 PM Eryu Guan <guan@eryu.me> wrote: > > > > > > On Thu, Apr 09, 2020 at 02:29:00PM +0300, Amir Goldstein wrote: > > > > When overlayfs index feature is enabled by default in either kernel > > > > config or module parameters, this test fails: > > > > > > > > mount: /tmp/8751/mnt: mount(2) system call failed: Stale file handle. > > > > cat: /tmp/8751/mnt/bar: No such file or directory > > > > > > > > The reason is that with index feature enabled, an upper/work dirs cannot > > > > be reused for mounting with a different lower layer. > > > > > > I re-built my test kernel with CONFIG_OVERLAY_FS_INDEX=y, and confirmed > > > /sys/module/overlay/parameters/index is 'Y', but test still passes for > > > me. And I do notice the following info in dmesg: > > > > > > [ 598.663923] overlayfs: fs on '/mnt/scratch/ovl-mnt/up' does not support file handles, falling back to index=off,nfs_export=off. > > > [ 598.674299] overlayfs: fs on '/mnt/scratch/ovl-mnt/low' does not support file handles, falling back to index=off,nfs_export=off. > > > [ 598.684594] overlayfs: fs on '/mnt/scratch/ovl-mnt/' does not support file handles, falling back to index=off,nfs_export=off. > > > > > > Seems it has something to do with nfs_export feature? I have it disabled > > > by default. > > > > > > # CONFIG_OVERLAY_FS_NFS_EXPORT is not set > > > > > > Could you please help confirm? > > > > > > > I confirm. enabling index on nested overlay requires that > > the lower overlay has nfs_export enabled. > > Thanks! > > > > > Missed that, but in the bug report, CONFIG_OVERLAY_FS_NFS_EXPORT > > was indeed set. > > Would you please update the commit log accordingly as well? > OK. Thanks, Amir.
diff --git a/tests/overlay/029 b/tests/overlay/029 index 1d2d2092..17f58de7 100755 --- a/tests/overlay/029 +++ b/tests/overlay/029 @@ -68,12 +68,18 @@ _overlay_mount_dirs $SCRATCH_MNT/up $tmp/{upper,work} \ cat $tmp/mnt/foo $UMOUNT_PROG $tmp/mnt +# re-create upper/work to avoid ovl_verify_origin() mount failure +# when index is enabled +rm -rf $tmp/{upper,work} +mkdir -p $tmp/{upper,work} # mount overlay again using lower dir from SCRATCH_MNT dir _overlay_mount_dirs $SCRATCH_MNT/low $tmp/{upper,work} \ overlay $tmp/mnt cat $tmp/mnt/bar $UMOUNT_PROG $tmp/mnt +rm -rf $tmp/{upper,work} +mkdir -p $tmp/{upper,work} # mount overlay again using SCRATCH_MNT dir _overlay_mount_dirs $SCRATCH_MNT/ $tmp/{upper,work} \ overlay $tmp/mnt
When overlayfs index feature is enabled by default in either kernel config or module parameters, this test fails: mount: /tmp/8751/mnt: mount(2) system call failed: Stale file handle. cat: /tmp/8751/mnt/bar: No such file or directory The reason is that with index feature enabled, an upper/work dirs cannot be reused for mounting with a different lower layer. Reported-by: Chengguang Xu <cgxu519@mykernel.net> Signed-off-by: Amir Goldstein <amir73il@gmail.com> --- tests/overlay/029 | 6 ++++++ 1 file changed, 6 insertions(+)