| Message ID | 55FCAB0E.3020707@sandisk.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 09/19/2015 02:23 AM, Bart Van Assche wrote: > Unregister and reregister BDI devices in the proper order. This patch > avoids that the following kernel warning can get triggered: > > WARNING: CPU: 7 PID: 203 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x68/0x80() > sysfs: cannot create duplicate filename '/devices/virtual/bdi/8:32' > Workqueue: events_unbound async_run_entry_fn > Call Trace: > [<ffffffff814ff5a4>] dump_stack+0x4c/0x65 > [<ffffffff810746ba>] warn_slowpath_common+0x8a/0xc0 > [<ffffffff81074736>] warn_slowpath_fmt+0x46/0x50 > [<ffffffff81237ca8>] sysfs_warn_dup+0x68/0x80 > [<ffffffff81237d8e>] sysfs_create_dir_ns+0x7e/0x90 > [<ffffffff81291f58>] kobject_add_internal+0xa8/0x320 > [<ffffffff812923a0>] kobject_add+0x60/0xb0 > [<ffffffff8138c937>] device_add+0x107/0x5e0 > [<ffffffff8138d018>] device_create_groups_vargs+0xd8/0x100 > [<ffffffff8138d05c>] device_create_vargs+0x1c/0x20 > [<ffffffff8117f233>] bdi_register+0x63/0x2a0 > [<ffffffff8117f497>] bdi_register_dev+0x27/0x30 > [<ffffffff81281549>] add_disk+0x1a9/0x4e0 > [<ffffffffa00c5739>] sd_probe_async+0x119/0x1d0 [sd_mod] > [<ffffffff8109a81a>] async_run_entry_fn+0x4a/0x140 > [<ffffffff81091078>] process_one_work+0x1d8/0x7c0 > [<ffffffff81091774>] worker_thread+0x114/0x460 > [<ffffffff81097878>] kthread+0xf8/0x110 > [<ffffffff8150801f>] ret_from_fork+0x3f/0x70 > > See also patch "block: destroy bdi before blockdev is unregistered" > (commit ID 6cd18e711dd8). > > Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> > Cc: Hannes Reinecke <hare@suse.de> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Martin K. Petersen <martin.petersen@oracle.com> > Cc: <stable@vger.kernel.org> > --- > drivers/scsi/scsi_sysfs.c | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c > index b333389..5e085d4 100644 > --- a/drivers/scsi/scsi_sysfs.c > +++ b/drivers/scsi/scsi_sysfs.c > @@ -1084,9 +1084,7 @@ void __scsi_remove_device(struct scsi_device *sdev) > device_unregister(&sdev->sdev_dev); > transport_remove_device(dev); > scsi_dh_remove_device(sdev); > - device_del(dev); > - } else > - put_device(&sdev->sdev_dev); > + } > > /* > * Stop accepting new requests and wait until all queuecommand() and > @@ -1097,6 +1095,16 @@ void __scsi_remove_device(struct scsi_device *sdev) > blk_cleanup_queue(sdev->request_queue); > cancel_work_sync(&sdev->requeue_work); > > + /* > + * Remove the device after blk_cleanup_queue() has been called such > + * a possible bdi_register() call with the same name occurs after > + * blk_cleanup_queue() has called bdi_destroy(). > + */ > + if (sdev->is_visible) > + device_del(dev); > + else > + put_device(&sdev->sdev_dev); > + > if (sdev->host->hostt->slave_destroy) > sdev->host->hostt->slave_destroy(sdev); > transport_destroy_device(dev); > Reviewed-by: Hannes Reinecke <hare@suse.com> Cheers, Hannes
On 9/19/2015 3:23 AM, Bart Van Assche wrote: > Unregister and reregister BDI devices in the proper order. This patch > avoids that the following kernel warning can get triggered: Hi Bart, Can you share the scenario that reproduced this? I think I might have seen this before. Thanks, Sagi. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/20/15 02:57, Sagi Grimberg wrote: > On 9/19/2015 3:23 AM, Bart Van Assche wrote: >> Unregister and reregister BDI devices in the proper order. This patch >> avoids that the following kernel warning can get triggered: > > Can you share the scenario that reproduced this? I think I might > have seen this before. Hello Sagi, The details of the setup on which I can reproduce the reported behavior easily are as follows: * Several kernel debugging options were enabled on the initiator system (PROVE_LOCKING, SLUB_DEBUG, KMEMLEAK, ...). * srp_daemon and multipathd were running on the initiator system. * Four IB ports were present the initiator system. * Eight IB ports were present the target system. * 100 LUNs were defined on the target system. * As a result, 3200 /dev/sd* device nodes were created on the initiator system by the SRP initiator driver. * The following command was run on the initiator system: for p in /sys/class/srp_remote_ports/*; do echo 1 >$p/delete & done; wait; dmsetup remove_all Bart. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index b333389..5e085d4 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -1084,9 +1084,7 @@ void __scsi_remove_device(struct scsi_device *sdev) device_unregister(&sdev->sdev_dev); transport_remove_device(dev); scsi_dh_remove_device(sdev); - device_del(dev); - } else - put_device(&sdev->sdev_dev); + } /* * Stop accepting new requests and wait until all queuecommand() and @@ -1097,6 +1095,16 @@ void __scsi_remove_device(struct scsi_device *sdev) blk_cleanup_queue(sdev->request_queue); cancel_work_sync(&sdev->requeue_work); + /* + * Remove the device after blk_cleanup_queue() has been called such + * a possible bdi_register() call with the same name occurs after + * blk_cleanup_queue() has called bdi_destroy(). + */ + if (sdev->is_visible) + device_del(dev); + else + put_device(&sdev->sdev_dev); + if (sdev->host->hostt->slave_destroy) sdev->host->hostt->slave_destroy(sdev); transport_destroy_device(dev);
Unregister and reregister BDI devices in the proper order. This patch avoids that the following kernel warning can get triggered: WARNING: CPU: 7 PID: 203 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x68/0x80() sysfs: cannot create duplicate filename '/devices/virtual/bdi/8:32' Workqueue: events_unbound async_run_entry_fn Call Trace: [<ffffffff814ff5a4>] dump_stack+0x4c/0x65 [<ffffffff810746ba>] warn_slowpath_common+0x8a/0xc0 [<ffffffff81074736>] warn_slowpath_fmt+0x46/0x50 [<ffffffff81237ca8>] sysfs_warn_dup+0x68/0x80 [<ffffffff81237d8e>] sysfs_create_dir_ns+0x7e/0x90 [<ffffffff81291f58>] kobject_add_internal+0xa8/0x320 [<ffffffff812923a0>] kobject_add+0x60/0xb0 [<ffffffff8138c937>] device_add+0x107/0x5e0 [<ffffffff8138d018>] device_create_groups_vargs+0xd8/0x100 [<ffffffff8138d05c>] device_create_vargs+0x1c/0x20 [<ffffffff8117f233>] bdi_register+0x63/0x2a0 [<ffffffff8117f497>] bdi_register_dev+0x27/0x30 [<ffffffff81281549>] add_disk+0x1a9/0x4e0 [<ffffffffa00c5739>] sd_probe_async+0x119/0x1d0 [sd_mod] [<ffffffff8109a81a>] async_run_entry_fn+0x4a/0x140 [<ffffffff81091078>] process_one_work+0x1d8/0x7c0 [<ffffffff81091774>] worker_thread+0x114/0x460 [<ffffffff81097878>] kthread+0xf8/0x110 [<ffffffff8150801f>] ret_from_fork+0x3f/0x70 See also patch "block: destroy bdi before blockdev is unregistered" (commit ID 6cd18e711dd8). Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: <stable@vger.kernel.org> --- drivers/scsi/scsi_sysfs.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)