zfs/module/zfs
jdike 4c98586daf Fix lockdep recursive locking false positive in dbuf_destroy
lockdep reports a possible recursive lock in dbuf_destroy.

It is true that dbuf_destroy is acquiring the dn_dbufs_mtx
on one dnode while holding it on another dnode.  However,
it is impossible for these to be the same dnode because,
among other things,dbuf_destroy checks MUTEX_HELD before
acquiring the mutex.

This fix defines a class NESTED_SINGLE == 1 and changes
that lock to call mutex_enter_nested with a subclass of
NESTED_SINGLE.

In order to make the userspace code compile,
include/sys/zfs_context.h now defines mutex_enter_nested and
NESTED_SINGLE.

This is the lockdep report:

[  122.950921] ============================================
[  122.950921] WARNING: possible recursive locking detected
[  122.950921] 4.19.29-4.19.0-debug-d69edad5368c1166 #1 Tainted: G           O
[  122.950921] --------------------------------------------
[  122.950921] dbu_evict/1457 is trying to acquire lock:
[  122.950921] 0000000083e9cbcf (&dn->dn_dbufs_mtx){+.+.}, at: dbuf_destroy+0x3c0/0xdb0 [zfs]
[  122.950921]
               but task is already holding lock:
[  122.950921] 0000000055523987 (&dn->dn_dbufs_mtx){+.+.}, at: dnode_evict_dbufs+0x90/0x740 [zfs]
[  122.950921]
               other info that might help us debug this:
[  122.950921]  Possible unsafe locking scenario:

[  122.950921]        CPU0
[  122.950921]        ----
[  122.950921]   lock(&dn->dn_dbufs_mtx);
[  122.950921]   lock(&dn->dn_dbufs_mtx);
[  122.950921]
                *** DEADLOCK ***

[  122.950921]  May be due to missing lock nesting notation

[  122.950921] 1 lock held by dbu_evict/1457:
[  122.950921]  #0: 0000000055523987 (&dn->dn_dbufs_mtx){+.+.}, at: dnode_evict_dbufs+0x90/0x740 [zfs]
[  122.950921]
               stack backtrace:
[  122.950921] CPU: 0 PID: 1457 Comm: dbu_evict Tainted: G           O      4.19.29-4.19.0-debug-d69edad5368c1166 #1
[  122.950921] Hardware name: Supermicro H8SSL-I2/H8SSL-I2, BIOS 080011  03/13/2009
[  122.950921] Call Trace:
[  122.950921]  dump_stack+0x91/0xeb
[  122.950921]  __lock_acquire+0x2ca7/0x4f10
[  122.950921]  lock_acquire+0x153/0x330
[  122.950921]  dbuf_destroy+0x3c0/0xdb0 [zfs]
[  122.950921]  dbuf_evict_one+0x1cc/0x3d0 [zfs]
[  122.950921]  dbuf_rele_and_unlock+0xb84/0xd60 [zfs]
[  122.950921]  dnode_evict_dbufs+0x3a6/0x740 [zfs]
[  122.950921]  dmu_objset_evict+0x7a/0x500 [zfs]
[  122.950921]  dsl_dataset_evict_async+0x70/0x480 [zfs]
[  122.950921]  taskq_thread+0x979/0x1480 [spl]
[  122.950921]  kthread+0x2e7/0x3e0
[  122.950921]  ret_from_fork+0x27/0x50

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jeff Dike <jdike@akamai.com>
Closes #8984
2019-09-25 11:27:49 -07:00
..
Makefile.in Add TRIM support 2019-03-29 09:13:20 -07:00
THIRDPARTYLICENSE.cityhash OpenZFS 8484 - Implement aggregate sum and use for arc counters 2018-06-06 09:35:59 -07:00
THIRDPARTYLICENSE.cityhash.descrip OpenZFS 8484 - Implement aggregate sum and use for arc counters 2018-06-06 09:35:59 -07:00
abd.c abd_alloc should use scatter for >1K allocations 2019-02-28 17:52:55 -08:00
aggsum.c OpenZFS 9688 - aggsum_fini leaks memory 2018-10-19 12:08:03 -07:00
arc.c Check b_freeze_cksum under ZFS_DEBUG_MODIFY conditional 2019-09-25 11:27:49 -07:00
blkptr.c Undo c89 workarounds to match with upstream 2017-11-04 13:25:13 -07:00
bplist.c Change KM_PUSHPAGE -> KM_SLEEP 2015-01-16 14:41:26 -08:00
bpobj.c Stack overflow in recursive bpobj_iterate_impl 2019-03-06 09:50:55 -08:00
bptree.c Native Encryption for ZFS on Linux 2017-08-14 10:36:48 -07:00
bqueue.c Wait in 'S' state when send/recv pipe is blocking 2019-06-07 12:45:40 -07:00
cityhash.c OpenZFS 8484 - Implement aggregate sum and use for arc counters 2018-06-06 09:35:59 -07:00
dataset_kstats.c port async unlinked drain from illumos-nexenta 2019-02-12 10:41:15 -08:00
dbuf.c Fix lockdep recursive locking false positive in dbuf_destroy 2019-09-25 11:27:49 -07:00
dbuf_stats.c Prefix all refcount functions with zfs_ 2018-10-01 10:42:05 -07:00
ddt.c ztest: scrub ddt repair 2019-01-17 15:25:00 -08:00
ddt_zap.c fat zap should prefetch when iterating 2019-09-25 11:27:47 -07:00
dmu.c fat zap should prefetch when iterating 2019-09-25 11:27:47 -07:00
dmu_diff.c Fix issues found with zfs diff 2018-05-01 11:24:20 -07:00
dmu_object.c Fix send/recv lost spill block 2019-05-07 15:18:44 -07:00
dmu_objset.c Avoid extra taskq_dispatch() calls by DMU 2019-09-25 11:27:48 -07:00
dmu_recv.c Allow unencrypted children of encrypted datasets 2019-09-25 11:27:48 -07:00
dmu_send.c Fix send/recv lost spill block 2019-05-07 15:18:44 -07:00
dmu_traverse.c Fix traverse_impl() kmem leak 2018-08-15 09:53:44 -07:00
dmu_tx.c dn_struct_rwlock can not be held in dmu_tx_try_assign() 2019-09-25 11:27:48 -07:00
dmu_zfetch.c Linux 5.2 compat: rw_tryupgrade() 2019-05-23 13:46:33 -07:00
dnode.c Export dnode symbols 2019-09-25 11:27:49 -07:00
dnode_sync.c Reinstate raw receive check when truncating 2019-06-07 12:45:40 -07:00
dsl_bookmark.c Detect and prevent mixed raw and non-raw sends 2019-03-13 11:00:43 -07:00
dsl_crypt.c Remove VERIFY from dsl_dataset_crypt_stats() 2019-09-25 11:27:49 -07:00
dsl_dataset.c Mutex leak in dsl_dataset_hold_obj() 2019-03-21 10:36:58 -07:00
dsl_deadlist.c OpenZFS 7614, 9064 - zfs device evacuation/removal 2018-04-14 12:16:17 -07:00
dsl_deleg.c Update build system and packaging 2018-05-29 16:00:33 -07:00
dsl_destroy.c Ensure dsl_destroy_head() decrypts objsets 2019-09-25 11:27:49 -07:00
dsl_dir.c Fix TXG_MASK cstyle 2019-04-12 11:30:59 -07:00
dsl_pool.c port async unlinked drain from illumos-nexenta 2019-02-12 10:41:15 -08:00
dsl_prop.c Update build system and packaging 2018-05-29 16:00:33 -07:00
dsl_scan.c Make zfs_async_block_max_blocks handle zero correctly 2019-06-07 12:45:40 -07:00
dsl_synctask.c OpenZFS 9166 - zfs storage pool checkpoint 2018-06-26 10:07:42 -07:00
dsl_userhold.c zfs should optionally send holds 2019-02-15 12:41:38 -08:00
edonr_zfs.c DLPX-44812 integrate EP-220 large memory scalability 2016-11-29 14:34:27 -08:00
fm.c OpenZFS 9580 - Add a hash-table on top of nvlist to speed-up operations 2018-07-30 11:30:03 -07:00
gzip.c Update build system and packaging 2018-05-29 16:00:33 -07:00
hkdf.c Encryption patch follow-up 2017-10-11 16:54:48 -04:00
lz4.c Reword comment in lz4_compress_zfs 2019-05-02 16:46:04 -07:00
lzjb.c Change KM_PUSHPAGE -> KM_SLEEP 2015-01-16 14:41:26 -08:00
metaslab.c Allow metaslab to be unloaded even when not freed from 2019-09-25 11:27:47 -07:00
mmp.c MMP interval and fail_intervals in uberblock 2019-03-21 12:47:57 -07:00
multilist.c Avoid extra taskq_dispatch() calls by DMU 2019-09-25 11:27:48 -07:00
pathname.c Disable unused pathname::pn_path* (unneeded in Linux) 2019-09-25 11:27:49 -07:00
policy.c Take user namespaces into account in policy checks 2018-03-07 15:40:42 -08:00
qat.c Code improvement and bug fixes for QAT support 2019-04-16 12:38:36 -07:00
qat.h Code improvement and bug fixes for QAT support 2019-04-16 12:38:36 -07:00
qat_compress.c Code improvement and bug fixes for QAT support 2019-04-16 12:38:36 -07:00
qat_crypt.c Code improvement and bug fixes for QAT support 2019-04-16 12:38:36 -07:00
range_tree.c Restrict kstats and print real pointers 2019-04-04 18:57:06 -07:00
refcount.c Add zfs_refcount_transfer_ownership_many() 2018-10-09 10:05:48 -07:00
rrwlock.c Prefix all refcount functions with zfs_ 2018-10-01 10:42:05 -07:00
sa.c Prefix all refcount functions with zfs_ 2018-10-01 10:42:05 -07:00
sha256.c SHA256 QAT acceleration 2018-03-15 10:53:58 -07:00
skein_zfs.c DLPX-44812 integrate EP-220 large memory scalability 2016-11-29 14:34:27 -08:00
spa.c zpool import progress kstat 2019-05-09 10:08:05 -07:00
spa_boot.c Add linux kernel module support 2010-08-31 13:41:58 -07:00
spa_checkpoint.c Get rid of space_map_update() for ms_synced_length 2019-02-12 10:38:11 -08:00
spa_config.c Remove vn_set_fs_pwd()/vn_set_pwd() (no need to be at / during insmod) 2019-09-25 11:27:46 -07:00
spa_errlog.c Update build system and packaging 2018-05-29 16:00:33 -07:00
spa_history.c Create /proc/sys/kernel/spl/gitrev with git hash 2018-10-08 21:57:02 -07:00
spa_misc.c Fix coverity defects: CID 186143 2019-06-07 12:39:13 -07:00
spa_stats.c Restrict kstats and print real pointers 2019-04-04 18:57:06 -07:00
space_map.c Restrict kstats and print real pointers 2019-04-04 18:57:06 -07:00
space_reftree.c OpenZFS 7614, 9064 - zfs device evacuation/removal 2018-04-14 12:16:17 -07:00
trace.c OpenZFS 7614, 9064 - zfs device evacuation/removal 2018-04-14 12:16:17 -07:00
txg.c Fix txg_wait_open() load average inflation 2019-04-04 09:44:46 -07:00
uberblock.c MMP interval and fail_intervals in uberblock 2019-03-21 12:47:57 -07:00
unique.c Performance optimization of AVL tree comparator functions 2016-08-31 14:35:34 -07:00
vdev.c Allow metaslab to be unloaded even when not freed from 2019-09-25 11:27:47 -07:00
vdev_cache.c Update build system and packaging 2018-05-29 16:00:33 -07:00
vdev_disk.c Update vdev_ops_t from illumos 2019-09-25 11:27:48 -07:00
vdev_file.c Update vdev_ops_t from illumos 2019-09-25 11:27:48 -07:00
vdev_indirect.c Update vdev_ops_t from illumos 2019-09-25 11:27:48 -07:00
vdev_indirect_births.c Fixes: #8934 Large kmem_alloc 2019-09-25 11:27:49 -07:00
vdev_indirect_mapping.c Get rid of space_map_update() for ms_synced_length 2019-02-12 10:38:11 -08:00
vdev_initialize.c Add TRIM support 2019-03-29 09:13:20 -07:00
vdev_label.c panic in removal_remap test on 4K devices 2019-09-25 11:27:47 -07:00
vdev_mirror.c Update vdev_ops_t from illumos 2019-09-25 11:27:48 -07:00
vdev_missing.c Update vdev_ops_t from illumos 2019-09-25 11:27:48 -07:00
vdev_queue.c Move write aggregation memory copy out of vq_lock 2019-09-25 11:27:47 -07:00
vdev_raidz.c Update vdev_ops_t from illumos 2019-09-25 11:27:48 -07:00
vdev_raidz_math.c Fix typo in vdev_raidz_math.c 2019-09-25 11:27:47 -07:00
vdev_raidz_math_aarch64_neon.c codebase style improvements for OpenZFS 6459 port 2017-01-22 13:25:40 -08:00
vdev_raidz_math_aarch64_neon_common.h Linux 5.0 compat: ASM_BUG macro 2019-05-08 10:18:40 -07:00
vdev_raidz_math_aarch64_neonx2.c ABD raidz NEON support 2016-11-29 14:34:33 -08:00
vdev_raidz_math_avx2.c Linux 5.0 compat: ASM_BUG macro 2019-05-08 10:18:40 -07:00
vdev_raidz_math_avx512bw.c Linux 5.0 compat: ASM_BUG macro 2019-05-08 10:18:40 -07:00
vdev_raidz_math_avx512f.c Use cstyle -cpP in `make cstyle` check 2016-12-12 10:46:26 -08:00
vdev_raidz_math_impl.h codebase style improvements for OpenZFS 6459 port 2017-01-22 13:25:40 -08:00
vdev_raidz_math_scalar.c ABD Vectorized raidz 2016-11-29 14:34:33 -08:00
vdev_raidz_math_sse2.c ABD raidz avx512f support 2016-11-29 14:34:33 -08:00
vdev_raidz_math_ssse3.c Linux 5.0 compat: ASM_BUG macro 2019-05-08 10:18:40 -07:00
vdev_removal.c panic in removal_remap test on 4K devices 2019-09-25 11:27:47 -07:00
vdev_root.c Update vdev_ops_t from illumos 2019-09-25 11:27:48 -07:00
vdev_trim.c Add TRIM support 2019-03-29 09:13:20 -07:00
zap.c fat zap should prefetch when iterating 2019-09-25 11:27:47 -07:00
zap_leaf.c Off-by-one in zap_leaf_array_create() 2019-01-18 09:58:46 -08:00
zap_micro.c fat zap should prefetch when iterating 2019-09-25 11:27:47 -07:00
zcp.c OpenZFS 9424 - ztest failure: "unprotected error in call to Lua API (Invalid value type 'function' for key 'error')" 2018-07-10 21:29:23 -07:00
zcp_get.c Fix get_special_prop() build failure 2019-09-25 11:27:49 -07:00
zcp_global.c OpenZFS 8600 - ZFS channel programs - snapshot 2018-02-08 15:29:24 -08:00
zcp_iter.c OpenZFS 9337 - zfs get all is slow due to uncached metadata 2018-07-12 10:49:27 -07:00
zcp_synctask.c OpenZFS 9166 - zfs storage pool checkpoint 2018-06-26 10:07:42 -07:00
zfeature.c Consistently captialize GUID for features 2019-04-16 10:01:51 -07:00
zfs_acl.c Update build system and packaging 2018-05-29 16:00:33 -07:00
zfs_byteswap.c Update build system and packaging 2018-05-29 16:00:33 -07:00
zfs_ctldir.c Use zfsctl_snapshot_hold() wrapper 2019-09-25 11:27:49 -07:00
zfs_debug.c Restrict kstats and print real pointers 2019-04-04 18:57:06 -07:00
zfs_dir.c port async unlinked drain from illumos-nexenta 2019-02-12 10:41:15 -08:00
zfs_fm.c Add zpool status -s (slow I/Os) and -p (parseable) 2018-11-08 16:47:24 -08:00
zfs_fuid.c Update build system and packaging 2018-05-29 16:00:33 -07:00
zfs_ioctl.c Remove vn_set_fs_pwd()/vn_set_pwd() (no need to be at / during insmod) 2019-09-25 11:27:46 -07:00
zfs_log.c Update build system and packaging 2018-05-29 16:00:33 -07:00
zfs_onexit.c Update build system and packaging 2018-05-29 16:00:33 -07:00
zfs_ratelimit.c Change checksum & IO delay ratelimit values 2018-03-04 17:34:51 -08:00
zfs_replay.c Use SEEK_{SET,CUR,END} for file seek "whence" 2019-04-25 10:17:27 -07:00
zfs_rlock.c OpenZFS 9689 - zfs range lock code should not be zpl-specific 2018-10-11 10:19:33 -07:00
zfs_sa.c Project Quota on ZFS 2018-02-13 14:54:54 -08:00
zfs_sysfs.c Prevent pointer to an out-of-scope local variable 2019-09-25 11:27:48 -07:00
zfs_vfsops.c Add missing trailing '\n' in printk() messages 2019-05-08 16:43:55 -07:00
zfs_vnops.c Update descriptions for vnops 2019-09-25 11:27:46 -07:00
zfs_znode.c Drop objid argument in zfs_znode_alloc() (sync with OpenZFS) 2019-09-25 11:27:46 -07:00
zil.c Fix the spelling of deferred 2019-04-16 10:01:45 -07:00
zio.c nopwrites on dmu_sync-ed blocks can result in a panic 2019-09-25 11:27:48 -07:00
zio_checksum.c Undo c89 workarounds to match with upstream 2017-11-04 13:25:13 -07:00
zio_compress.c OpenZFS 9403 - assertion failed in arc_buf_destroy() 2018-08-29 11:33:33 -07:00
zio_crypt.c Always call rw_init in zio_crypt_key_unwrap 2019-04-10 15:39:40 -07:00
zio_inject.c Multiple DVA Scrubbing Fix 2019-03-15 14:14:31 -07:00
zle.c Fix zle_decompress out of bound access 2018-02-09 10:08:05 -08:00
zpl_ctldir.c RHEL 7.5 compat: FMODE_KABI_ITERATE 2018-05-02 15:01:24 -07:00
zpl_export.c Use cstyle -cpP in `make cstyle` check 2016-12-12 10:46:26 -08:00
zpl_file.c Fix errant EFAULT during writes (#8719) 2019-05-08 10:04:04 -07:00
zpl_inode.c Fix errant EFAULT during writes (#8719) 2019-05-08 10:04:04 -07:00
zpl_super.c Fix statfs(2) for 32-bit user space 2018-09-24 17:11:25 -07:00
zpl_xattr.c Drop redundant POSIX ACL check in zpl_init_acl() 2019-09-25 11:27:49 -07:00
zrlock.c Update build system and packaging 2018-05-29 16:00:33 -07:00
zthr.c Fix txg_wait_open() load average inflation 2019-04-04 09:44:46 -07:00
zvol.c Add SCSI_PASSTHROUGH to zvols to enable UNMAP support 2019-09-25 11:27:48 -07:00