On 22/11/2017 9:14 PM, Stefan Priebe - Profihost AG wrote:

Am 22.11.2017 um 13:57 schrieb Coly Li:

quoted

On 22/11/2017 8:26 PM, Stefan Priebe - Profihost AG wrote:

quoted

Am 22.11.2017 um 13:16 schrieb Coly Li:

quoted

On 22/11/2017 7:23 PM, Stefan Priebe - Profihost AG wrote:

quoted

Hello,

i've 6 bcache blk devices attached to 3 caching ssds (2 each). One fails
to register automatically at boot time.

After reboot i always need to execute:
echo /dev/sdf1 >/sys/fs/bcache/register

to bring up the bcache device.

Any idea?

Hi Stefan,

Is there any clue from kernel message ?

Sadly not.

Working one:
]# dmesg | grep sdi
[    1.060377] sd 5:0:0:0: [sdi] 1953525168 512-byte logical blocks:
(1.00 TB/932 GiB)
[    1.060393] sd 5:0:0:0: [sdi] Write Protect is off
[    1.060396] sd 5:0:0:0: [sdi] Mode Sense: 00 3a 00 00
[    1.060425] sd 5:0:0:0: [sdi] Write cache: enabled, read cache:
enabled, doesn't support DPO or FUA
[    1.104341]  sdi: sdi1
[    1.104644] sd 5:0:0:0: [sdi] Attached SCSI disk
[    2.005452] bcache: register_bdev() registered backing device sdi1
[    2.045211] bcache: bch_cached_dev_attach() Caching sdi1 as bcache0
on set 76b95bf8-9cc7-407f-9f9e-a42b6d1bcb27


not working one:
# dmesg | grep sdf
[    0.946107] sd 0:0:5:0: [sdf] 1953525168 512-byte logical blocks:
(1.00 TB/932 GiB)
[    1.400267] sd 0:0:5:0: [sdf] Write Protect is off
[    1.400267] sd 0:0:5:0: [sdf] Mode Sense: 00 00 00 00
[    1.401347] sd 0:0:5:0: [sdf] Write cache: enabled, read cache:
enabled, supports DPO and FUA
[    1.902910]  sdf: sdf1
[    2.341289] sd 0:0:5:0: [sdf] Attached SCSI disk
[  295.458804] bcache: register_bdev() registered backing device sdf1
[  295.506656] bcache: bch_cached_dev_attach() Caching sdf1 as bcache5
on set 76b95bf8-9cc7-407f-9f9e-a42b6d1bcb27

At 295s i registeeed it manually.

Hi Stefan,

Hmm, I don't have idea here. Anyway, is the cache mode set as writeback?
Recently I post a patch to fix a potential deadlock between writeback
rate update kworker and register code, I am not sure whether it is
relative to your issue, but at least we can have a try. the patch title is:
 [RFC] bcache: fix a circular dead locking with dc->writeback_lock and
bch_register_lock

Just for your information.

i can try that one - can you please resend? I can't find that mail and
don't know how to grab that one our of the web html archives to apply
correctly.

Hi Stefan,

Can you download the patch from following URL:
https://git.kernel.org/pub/scm/linux/kernel/git/colyli/bcache-patches.git/plain/for-test/0001-bcache-fix-a-circular-dead-locking-with-dc-writeback.patch

Coly Li