On Sat, 2022-03-05 at 20:46 +0800, ChenXiaoSong wrote: > filemap_sample_wb_err() will return 0 if nobody has seen the error > yet, > then filemap_check_wb_err() will return the unchanged writeback > error. > > Reproducer: > nfs server | nfs client > --------------------------------|----------------------------------- > ------------ > # No space left on server | > fallocate -l 100G /server/file1 | > | mount -t nfs $nfs_server_ip:/ /mnt > | # Expected error: No space left on > device > | dd if=/dev/zero of=/mnt/file2 > count=1 ibs=100K > # Release space on server | > rm /server/file1 | > | # Unexpected error: No space left > on device > | dd if=/dev/zero of=/mnt/file2 > count=1 ibs=100K > 'rm' doesn't open any files or do any I/O, so it shouldn't be returning any errors from the page cache. IOW: The problem here is not that we're failing to clear an error from the page cache. It is that something in 'rm' is checking the page cache and returning any errors that it finds there. Is 'rm' perhaps doing a stat() on the file it is deleting? If so, does this patch fix the bug? https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/comm it/?id=d19e0183a883 -- Trond Myklebust Linux NFS client maintainer, Hammerspace trond.myklebust@xxxxxxxxxxxxxxx
