On Mon, Jun 02, 2014 at 02:22:15PM +0300, Martin Papik wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA512 > > > >> How can I detect this situation? I mean I didn't see anything in > >> /proc/mounts or references to the mount point from /proc/<pid>/*, > >> so I only managed to correct it (chdir elsewhere) by chance on a > >> hunch. Would it not be desirable to know that there's a phantom > >> FS referenced by a number of processes? > > > > lsof. > > No good. lsof reports such things as belonging to / because it can't find the correct path for them. Indeed, you can't find them by filtering on mount point, file or anything else. But they are there. e.g: $ sudo mount /dev/vdc /mnt/scratch $ cd /mnt/scratch $ sudo umount -l /mnt/scratch $ sleep 300 $ cd ~ $ ps -ef |grep [s]leep dave 16341 7432 0 09:27 pts/1 00:00:00 sleep 300 $ sudo lsof |grep sleep sleep 16341 dave cwd DIR 253,32 6 96 / sleep 16341 dave rtd DIR 8,1 4096 2 / sleep 16341 dave txt REG 8,1 31208 32607 /bin/sleep sleep 16341 dave mem REG 8,1 1742520 245384 /lib/x86_64-linux-gnu/libc-2.17.so sleep 16341 dave mem REG 8,1 145160 245381 /lib/x86_64-linux-gnu/ld-2.17.so sleep 16341 dave mem REG 8,1 1607584 98063 /usr/lib/locale/locale-archive sleep 16341 dave 0u CHR 136,1 0t0 4 /dev/pts/1 sleep 16341 dave 1u CHR 136,1 0t0 4 /dev/pts/1 sleep 16341 dave 2u CHR 136,1 0t0 4 /dev/pts/1 See the first two DIR lines? They have different devices but the same path (/). That's what you need to look for - the non-root device with a root path - in this case 253,32: $ ls -l /dev/vdc brw-rw---- 1 root disk 253, 32 Jun 3 09:01 /dev/vdc $ With this knowledge, the simple way: $ sudo lsof |grep "253,32" bash 7432 dave cwd DIR 253,32 6 96 / sleep 16341 dave cwd DIR 253,32 6 96 / There's the two processes holding references to the unmounted filesystem. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
