On Mon, Jan 30, 2017 at 08:05:52AM +0100, Hannes Reinecke wrote: > On 01/29/2017 05:58 AM, Dan Williams wrote: > > Warnings of the following form occur because scsi reuses a devt number > > while the block layer still has it referenced as the name of the bdi > > [1]: > > > > WARNING: CPU: 1 PID: 93 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80 > > sysfs: cannot create duplicate filename '/devices/virtual/bdi/8:192' > > [..] > > Call Trace: > > dump_stack+0x86/0xc3 > > __warn+0xcb/0xf0 > > warn_slowpath_fmt+0x5f/0x80 > > ? kernfs_path_from_node+0x4f/0x60 > > sysfs_warn_dup+0x62/0x80 > > sysfs_create_dir_ns+0x77/0x90 > > kobject_add_internal+0xb2/0x350 > > kobject_add+0x75/0xd0 > > device_add+0x15a/0x650 > > device_create_groups_vargs+0xe0/0xf0 > > device_create_vargs+0x1c/0x20 > > bdi_register+0x90/0x240 > > ? lockdep_init_map+0x57/0x200 > > bdi_register_owner+0x36/0x60 > > device_add_disk+0x1bb/0x4e0 > > ? __pm_runtime_use_autosuspend+0x5c/0x70 > > sd_probe_async+0x10d/0x1c0 > > async_run_entry_fn+0x39/0x170 > > > > This is a brute-force fix to pass the devt release information from > > sd_probe() to the locations where we register the bdi, > > device_add_disk(), and unregister the bdi, blk_cleanup_queue(). > > > > Thanks to Omar for the quick reproducer script [2]. This patch survives > > where an unmodified kernel fails in a few seconds. > > > > [1]: https://marc.info/?l=linux-scsi&m=147116857810716&w=4 > > [2]: http://marc.info/?l=linux-block&m=148554717109098&w=2 > > > > Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> > > Cc: Bart Van Assche <bart.vanassche@xxxxxxxxxxx> > > Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx> > > Cc: Christoph Hellwig <hch@xxxxxx> > > Cc: Jens Axboe <axboe@xxxxxxxxx> > > Reported-by: Omar Sandoval <osandov@xxxxxxxxxxx> > > Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> > > --- > > block/blk-core.c | 1 + > > block/genhd.c | 7 +++++++ > > drivers/scsi/sd.c | 41 +++++++++++++++++++++++++++++++++-------- > > include/linux/blkdev.h | 1 + > > include/linux/genhd.h | 17 +++++++++++++++++ > > 5 files changed, 59 insertions(+), 8 deletions(-) > > > Please check the patchset from Jan Kara (cf 'BDI lifetime fix' on > linux-block), which attempts to solve the same problem. Hi, Hannes, It's not the same problem. Jan's series fixes a bdi vs. inode lifetime issue, this patch is for a bdi vs devt lifetime issue. Jan's series doesn't fix the crashes caused by my reproducer script. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
