On Mon, Jan 14 2013 at 5:53pm -0500, Mike Snitzer <snitzer@xxxxxxxxxx> wrote: > On Mon, Jan 14 2013 at 5:37pm -0500, > Kent Overstreet <koverstreet@xxxxxxxxxx> wrote: > > > Want to try again with the latest bcache-for-upstream branch? I fixed > > all that sysfs stuff, but I wasn't seeing the original build error so > > I'd appreciate if you verify I did in fact fix that issue. > > Will do, thanks Kent. I hit the crash below if I do this in a script: echo 1 > /sys/block/bcache0/bcache/cache/unregister echo 1 > /sys/block/bcache0/bcache/stop I have a workaround for this issue (just wait a few seconds between commands). I'm still carrying on testing and will share some preliminary performance results vs dm-cache soon. ------------[ cut here ]------------ bcache: bcache0 stopped WARNING: at fs/sysfs/inode.c:324 sysfs_hash_and_remove+0xa4/0xb0() Hardware name: PRIMERGY RX300 S6 sysfs: can not remove 'cache', no directory Modules linked in: dm_cache_cleaner(O) dm_cache_mq(O) dm_cache_basic(O) dm_cache(O) dm_thin_pool(O) dm_bio_prison dm_persistent_data(O) dm_bufio libcrc32c dm_mod(O) bc ache ebtable_nat ebtables xt_CHECKSUM iptable_mangle bridge autofs4 target_core_iblock target_core_file target_core_pscsi target_core_mod configfs bnx2fc fcoe libfcoe 8021q libfc garp stp llc scsi_transport_fc scsi_tgt sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip _tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables bnx2i cnic uio ipv6 cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi vhost_net macvtap macvlan tun iTCO_wdt iTCO_vendor_support kvm_intel kvm microcode i2c_i801 i2c_core lpc_ich mfd_core igb i7 core_edac edac_core iomemory_vsl(O) skd(O) ixgbe dca ptp pps_core mdio sg ses enclosure ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix megaraid_sas [last unloaded: dm_cache_basic] Pid: 81, comm: kworker/8:1 Tainted: G W O 3.8.0-rc3.snitm+ #37 Call Trace: [<ffffffff810423bf>] warn_slowpath_common+0x7f/0xc0 [<ffffffff810424b6>] warn_slowpath_fmt+0x46/0x50 [<ffffffff811db784>] sysfs_hash_and_remove+0xa4/0xb0 [<ffffffff811de476>] sysfs_remove_link+0x26/0x30 [<ffffffffa0719e26>] cached_dev_detach_finish+0x86/0x150 [bcache] [<ffffffff81236507>] ? ioc_release_fn+0x87/0xc0 [<ffffffff8105f307>] process_one_work+0x177/0x430 [<ffffffffa0719da0>] ? flash_dev_free+0x30/0x30 [bcache] [<ffffffff8106129e>] worker_thread+0x12e/0x380 [<ffffffff81061170>] ? manage_workers+0x180/0x180 [<ffffffff8106650e>] kthread+0xce/0xe0 [<ffffffff81066440>] ? kthread_freezable_should_stop+0x70/0x70 [<ffffffff814ff06c>] ret_from_fork+0x7c/0xb0 [<ffffffff81066440>] ? kthread_freezable_should_stop+0x70/0x70 ---[ end trace 50d16ffe964021b2 ]--- bcache: Cache set 4e51cb30-a889-48b2-88cd-a61bd788eac0 unregistered BUG: unable to handle kernel NULL pointer dereference at 0000000000000cc8 IP: [<ffffffffa0719bc7>] bcache_device_detach+0x77/0xb0 [bcache] PGD 0 Oops: 0000 [#1] SMP Modules linked in: dm_cache_cleaner(O) dm_cache_mq(O) dm_cache_basic(O) dm_cache(O) dm_thin_pool(O) dm_bio_prison dm_persistent_data(O) dm_bufio libcrc32c dm_mod(O) bc ache ebtable_nat ebtables xt_CHECKSUM iptable_mangle bridge autofs4 target_core_iblock target_core_file target_core_pscsi target_core_mod configfs bnx2fc fcoe libfcoe 8021q libfc garp stp llc scsi_transport_fc scsi_tgt sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip _tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables bnx2i cnic uio ipv6 cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi vhost_net macvtap macvlan tun iTCO_wdt iTCO_vendor_support kvm_intel kvm microcode i2c_i801 i2c_core lpc_ich mfd_core igb i7 core_edac edac_core iomemory_vsl(O) skd(O) ixgbe dca ptp pps_core mdio sg ses enclosure ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix megaraid_sas [last unloaded: dm_cache_basic] CPU 8 Pid: 81, comm: kworker/8:1 Tainted: G W O 3.8.0-rc3.snitm+ #37 FUJITSU PRIMERGY RX300 S6 /D2619 RIP: 0010:[<ffffffffa0719bc7>] [<ffffffffa0719bc7>] bcache_device_detach+0x77/0xb0 [bcache] RSP: 0018:ffff88032dc69d38 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88031c950010 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff880331a2a0c0 RDI: ffff88031c950010 RBP: ffff88032dc69d48 R08: ffff88032dc68000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88031c950aa8 R13: ffff88032dc69d58 R14: 0000000000000000 R15: ffff88033fd15c05 FS: 0000000000000000(0000) GS:ffff88033fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000cc8 CR3: 0000000001a0c000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process kworker/8:1 (pid: 81, threadinfo ffff88032dc68000, task ffff880331a2a0c0) Stack: ffff88031c950000 ffff88031c950aa8 ffff88032dc69dd8 ffffffffa0719e76 0000000000000000 ffff880331a2a0c0 0000000000000000 0000000000000000 0000000000000000 00000000a0200001 ffff88032c22d5d8 0000000000000292 Call Trace: [<ffffffffa0719e76>] cached_dev_detach_finish+0xd6/0x150 [bcache] [<ffffffff81236507>] ? ioc_release_fn+0x87/0xc0 [<ffffffff8105f307>] process_one_work+0x177/0x430 [<ffffffffa0719da0>] ? flash_dev_free+0x30/0x30 [bcache] [<ffffffff8106129e>] worker_thread+0x12e/0x380 [<ffffffff81061170>] ? manage_workers+0x180/0x180 [<ffffffff8106650e>] kthread+0xce/0xe0 [<ffffffff81066440>] ? kthread_freezable_should_stop+0x70/0x70 [<ffffffff814ff06c>] ret_from_fork+0x7c/0xb0 [<ffffffff81066440>] ? kthread_freezable_should_stop+0x70/0x70 Code: 00 00 49 89 44 24 08 e8 f8 ae 97 e0 41 89 44 24 38 48 8b 7b 70 e8 5a ff ff ff c7 83 94 00 00 00 00 00 00 00 48 8b 43 70 8b 53 78 <48> 8b 80 c8 0c 00 00 48 c7 04 d0 00 00 00 00 48 8b 7b 70 48 81 RIP [<ffffffffa0719bc7>] bcache_device_detach+0x77/0xb0 [bcache] RSP <ffff88032dc69d38> CR2: 0000000000000cc8 ---[ end trace 50d16ffe964021b3 ]--- BUG: unable to handle kernel paging request at ffffffffffffffd8 IP: [<ffffffff81065e40>] kthread_data+0x10/0x20 PGD 1a0e067 PUD 1a0f067 PMD 0 Oops: 0000 [#2] SMP Modules linked in: dm_cache_cleaner(O) dm_cache_mq(O) dm_cache_basic(O) dm_cache(O) dm_thin_pool(O) dm_bio_prison dm_persistent_data(O) dm_bufio libcrc32c dm_mod(O) bc ache ebtable_nat ebtables xt_CHECKSUM iptable_mangle bridge autofs4 target_core_iblock target_core_file target_core_pscsi target_core_mod configfs bnx2fc fcoe libfcoe 8021q libfc garp stp llc scsi_transport_fc scsi_tgt sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip _tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables bnx2i cnic uio ipv6 cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi vhost_net macvtap macvlan tun iTCO_wdt iTCO_vendor_support kvm_intel kvm microcode i2c_i801 i2c_core lpc_ich mfd_core igb i7 core_edac edac_core iomemory_vsl(O) skd(O) ixgbe dca ptp pps_core mdio sg ses enclosure ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix megaraid_sas [last unloaded: dm_cache_basic] CPU 8 Pid: 81, comm: kworker/8:1 Tainted: G D W O 3.8.0-rc3.snitm+ #37 FUJITSU PRIMERGY RX300 S6 /D2619 RIP: 0010:[<ffffffff81065e40>] [<ffffffff81065e40>] kthread_data+0x10/0x20 RSP: 0018:ffff88032dc69968 EFLAGS: 00010086 RAX: 0000000000000000 RBX: ffff88033fd12980 RCX: ffffffff81d8e3a0 RDX: 000000000000000d RSI: 0000000000000008 RDI: ffff880331a2a0c0 RBP: ffff88032dc69968 R08: ffff880331a2a130 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000008 R13: 0000000000000008 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88033fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffffffffffffffd8 CR3: 0000000001a0c000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process kworker/8:1 (pid: 81, threadinfo ffff88032dc68000, task ffff880331a2a0c0) Stack: ffff88032dc69998 ffffffff8105e571 0000000000000008 ffff88033fd12980 0000000000000008 ffff880331a2a690 ffff88032dc69a28 ffffffff814f55f3 ffff88032dc69fd8 0000000000012980 ffff88032dc68010 0000000000012980 Call Trace: [<ffffffff8105e571>] wq_worker_sleeping+0x21/0xa0 [<ffffffff814f55f3>] __schedule+0x5a3/0x710 [<ffffffff814f5a99>] schedule+0x29/0x70 [<ffffffff81048515>] do_exit+0x2c5/0x470 [<ffffffff814f790c>] oops_end+0xac/0xf0 [<ffffffff81035e0e>] no_context+0x11e/0x1f0 [<ffffffff8103601d>] __bad_area_nosemaphore+0x13d/0x220 [<ffffffff81081d98>] ? load_balance+0x128/0x670 [<ffffffff81036113>] bad_area_nosemaphore+0x13/0x20 [<ffffffff814fa65a>] __do_page_fault+0x27a/0x490 [<ffffffff810018d7>] ? __switch_to+0x157/0x4f0 [<ffffffff810827f0>] ? idle_balance+0x1c0/0x320 [<ffffffff814fa87e>] do_page_fault+0xe/0x10 [<ffffffff814f6d48>] page_fault+0x28/0x30 [<ffffffffa0719bc7>] ? bcache_device_detach+0x77/0xb0 [bcache] [<ffffffffa0719e76>] cached_dev_detach_finish+0xd6/0x150 [bcache] [<ffffffff81236507>] ? ioc_release_fn+0x87/0xc0 [<ffffffff8105f307>] process_one_work+0x177/0x430 [<ffffffffa0719da0>] ? flash_dev_free+0x30/0x30 [bcache] [<ffffffff8106129e>] worker_thread+0x12e/0x380 [<ffffffff81061170>] ? manage_workers+0x180/0x180 [<ffffffff8106650e>] kthread+0xce/0xe0 [<ffffffff81066440>] ? kthread_freezable_should_stop+0x70/0x70 [<ffffffff814ff06c>] ret_from_fork+0x7c/0xb0 [<ffffffff81066440>] ? kthread_freezable_should_stop+0x70/0x70 Code: 78 05 00 00 48 8b 40 c8 c9 48 c1 e8 02 83 e0 01 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 66 66 66 66 90 48 8b 87 78 05 00 00 <48> 8b 40 d8 c9 c3 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 66 RIP [<ffffffff81065e40>] kthread_data+0x10/0x20 RSP <ffff88032dc69968> CR2: ffffffffffffffd8 ---[ end trace 50d16ffe964021b4 ]--- Fixing recursive fault but reboot is needed! -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel