Re: Linux 6.1.56

["poester" <poester@internetbrands.com>]

Since rolling out 6.1.56 we have been experiencing file corruption
over NFSv3.  We bisected it down to

 f16fd0b11f0f NFS: Fix error handling for O_DIRECT write scheduling

But that doesn't cleanly revert so we ended up reverting all NFS
changes from 6.1.56 and the corruption no longer occurs.  Namely:

 edd1f0614510 NFS: More fixes for nfs_direct_write_reschedule_io()
 d4729af1c73c NFS: Use the correct commit info in nfs_join_page_group()
 1f49386d6779 NFS: More O_DIRECT accounting fixes for error paths
 4d98038e5bd9 NFS: Fix O_DIRECT locking issues
 f16fd0b11f0f NFS: Fix error handling for O_DIRECT write scheduling

The test case is fairly easily reproduced for us:

 dd if=testfile of=testfile2 oflag=direct; md5sum testfile*

shows a different md5sum between the two files on 6.1.56+ kernels.
Interestingly, on 6.5.7 this problem does not occur even though it
contains the same O_DIRECT patch as f16fd0b11f0f.

We opened a bugzilla on this:

 https://bugzilla.kernel.org/show_bug.cgi?id=217999

But this seems like a critical issue to us which should likely be
addressed in 6.1.58.

Thanks,
Phil