It does not pass even the self tests and qgroup creation:
[ 26.275106] Btrfs loaded, crc32c=crc32c-intel, debug=on, integrity-checker=on, ref-verify=on
[ 26.278075] BTRFS: selftest: sectorsize: 4096 nodesize: 4096
[ 26.279861] BTRFS: selftest: running btrfs free space cache tests
[ 26.281735] BTRFS: selftest: running extent only tests
[ 26.283317] BTRFS: selftest: running bitmap only tests
[ 26.284966] BTRFS: selftest: running bitmap and extent tests
[ 26.286842] BTRFS: selftest: running space stealing from bitmap to extent tests
[ 26.289587] BTRFS: selftest: running extent buffer operation tests
[ 26.291507] BTRFS: selftest: running btrfs_split_item tests
[ 26.293401] BTRFS: selftest: running extent I/O tests
[ 26.295059] BTRFS: selftest: running find delalloc tests
[ 26.475777] BTRFS: selftest: running find_first_clear_extent_bit test
[ 26.477812] BTRFS: selftest: running extent buffer bitmap tests
[ 26.499493] BTRFS: selftest: running inode tests
[ 26.501164] BTRFS: selftest: running btrfs_get_extent tests
[ 26.503599] BTRFS: selftest: running hole first btrfs_get_extent test
[ 26.505971] BTRFS: selftest: running outstanding_extents tests
[ 26.508136] BTRFS: selftest: running qgroup tests
[ 26.509820] BTRFS: selftest: running qgroup add/remove tests
[ 26.511566] BUG: sleeping function called from invalid context at mm/slab.h:567
[ 26.514058] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 117, name: modprobe
[ 26.516671] 2 locks held by modprobe/117:
[ 26.517980] #0: ffff968162761a08 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_create_qgroup+0x29/0xf0 [btrfs]
[ 26.521114] #1: ffff968162761960 (&fs_info->qgroup_lock){+.+.}-{2:2}, at: btrfs_create_qgroup+0x75/0xf0 [btrfs]
[ 26.524120] CPU: 1 PID: 117 Comm: modprobe Not tainted 5.8.0-rc2-default+ #1154
[ 26.526439] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 26.529612] Call Trace:
[ 26.530731] dump_stack+0x78/0xa0
[ 26.531983] ___might_sleep.cold+0xa6/0xf9
[ 26.533290] ? kobject_set_name_vargs+0x1e/0x90
[ 26.534674] __kmalloc_track_caller+0x143/0x340
[ 26.536122] kvasprintf+0x64/0xc0
[ 26.537257] kobject_set_name_vargs+0x1e/0x90
[ 26.538588] kobject_init_and_add+0x5d/0xa0
[ 26.539878] ? lockdep_init_map_waits+0x4d/0x200
[ 26.541398] btrfs_sysfs_add_one_qgroup+0x72/0xa0 [btrfs]
[ 26.543146] add_qgroup_rb+0xb0/0x140 [btrfs]
[ 26.544556] btrfs_create_qgroup+0x80/0xf0 [btrfs]
[ 26.546006] test_no_shared_qgroup.isra.0+0x66/0x2b0 [btrfs]
[ 26.547583] btrfs_test_qgroups+0x1da/0x220 [btrfs]
[ 26.549015] btrfs_run_sanity_tests.cold+0x5c/0xd5 [btrfs]
[ 26.550759] ? 0xffffffffc0518000
[ 26.551911] init_btrfs_fs+0xf1/0x159 [btrfs]
[ 26.553306] do_one_initcall+0x63/0x320
[ 26.554609] ? rcu_read_lock_sched_held+0x5d/0x90
[ 26.564925] ? do_init_module+0x23/0x220
[ 26.566180] ? kmem_cache_alloc_trace+0x17b/0x2f0
[ 26.567721] do_init_module+0x5c/0x220
[ 26.568978] load_module+0xed8/0x1490
[ 26.570252] ? __do_sys_finit_module+0xbf/0xe0
[ 26.571618] __do_sys_finit_module+0xbf/0xe0
[ 26.572955] do_syscall_64+0x50/0xe0
[ 26.574221] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 26.575812] RIP: 0033:0x7fc269fa6649
[ 26.577191] Code: Bad RIP value.
[ 26.578341] RSP: 002b:00007ffffdc63a88 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 26.580890] RAX: ffffffffffffffda RBX: 000055c8d63eba50 RCX: 00007fc269fa6649
[ 26.582850] RDX: 0000000000000000 RSI: 000055c8d63c49d2 RDI: 000000000000000a
[ 26.584887] RBP: 0000000000040000 R08: 0000000000000000 R09: 000055c8d63eedf0
[ 26.586923] R10: 000000000000000a R11: 0000000000000246 R12: 000055c8d63c49d2
[ 26.589341] R13: 000055c8d63e6f10 R14: 0000000000000000 R15: 000055c8d63ee530
[ 26.591720]
[ 26.592542] =============================
[ 26.593931] [ BUG: Invalid wait context ]
[ 26.595453] 5.8.0-rc2-default+ #1154 Tainted: G W
[ 26.597191] -----------------------------
[ 26.598478] modprobe/117 is trying to lock:
[ 26.599887] ffffffff8a11e370 (kernfs_mutex){+.+.}-{3:3}, at: kernfs_add_one+0x23/0x150
[ 26.602366] other info that might help us debug this:
[ 26.604184] context-{4:4}
[ 26.605379] 2 locks held by modprobe/117:
[ 26.606868] #0: ffff968162761a08 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_create_qgroup+0x29/0xf0 [btrfs]
[ 26.610376] #1: ffff968162761960 (&fs_info->qgroup_lock){+.+.}-{2:2}, at: btrfs_create_qgroup+0x75/0xf0 [btrfs]
[ 26.613764] stack backtrace:
[ 26.615038] CPU: 1 PID: 117 Comm: modprobe Tainted: G W 5.8.0-rc2-default+ #1154
[ 26.618100] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 26.621610] Call Trace:
[ 26.622731] dump_stack+0x78/0xa0
[ 26.624089] __lock_acquire.cold+0xa0/0x16c
[ 26.625593] lock_acquire+0xa3/0x440
[ 26.626951] ? kernfs_add_one+0x23/0x150
[ 26.628531] __mutex_lock+0xa0/0xaf0
[ 26.629958] ? kernfs_add_one+0x23/0x150
[ 26.631496] ? kernfs_add_one+0x23/0x150
[ 26.633669] ? kernfs_add_one+0x23/0x150
[ 26.635813] kernfs_add_one+0x23/0x150
[ 26.637438] kernfs_create_dir_ns+0x58/0x80
[ 26.638987] sysfs_create_dir_ns+0x70/0xd0
[ 26.640328] ? rcu_read_lock_sched_held+0x5d/0x90
[ 26.641799] kobject_add_internal+0xbb/0x2d0
[ 26.643162] kobject_init_and_add+0x71/0xa0
[ 26.644452] ? lockdep_init_map_waits+0x4d/0x200
[ 26.645889] btrfs_sysfs_add_one_qgroup+0x72/0xa0 [btrfs]
[ 26.647602] add_qgroup_rb+0xb0/0x140 [btrfs]
[ 26.649053] btrfs_create_qgroup+0x80/0xf0 [btrfs]
[ 26.650521] test_no_shared_qgroup.isra.0+0x66/0x2b0 [btrfs]
[ 26.652225] btrfs_test_qgroups+0x1da/0x220 [btrfs]
[ 26.653787] btrfs_run_sanity_tests.cold+0x5c/0xd5 [btrfs]
[ 26.655338] ? 0xffffffffc0518000
[ 26.656510] init_btrfs_fs+0xf1/0x159 [btrfs]
[ 26.657905] do_one_initcall+0x63/0x320
[ 26.659167] ? rcu_read_lock_sched_held+0x5d/0x90
[ 26.660563] ? do_init_module+0x23/0x220
[ 26.661841] ? kmem_cache_alloc_trace+0x17b/0x2f0
[ 26.663226] do_init_module+0x5c/0x220
[ 26.664428] load_module+0xed8/0x1490
[ 26.665607] ? __do_sys_finit_module+0xbf/0xe0
[ 26.666952] __do_sys_finit_module+0xbf/0xe0
[ 26.668253] do_syscall_64+0x50/0xe0
[ 26.669422] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 26.670981] RIP: 0033:0x7fc269fa6649
And creating a qgoup fires the same warning:
[ 145.501257] BUG: sleeping function called from invalid context at mm/slab.h:567
[ 145.506681] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 152, name: btrfs
[ 145.521473] INFO: lockdep is turned off.
[ 145.523000] CPU: 2 PID: 152 Comm: btrfs Tainted: G W 5.8.0-rc2-default+ #1154
[ 145.526231] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 145.530130] Call Trace:
[ 145.531296] dump_stack+0x78/0xa0
[ 145.532703] ___might_sleep.cold+0xa6/0xf9
[ 145.534287] ? kobject_set_name_vargs+0x1e/0x90
[ 145.536066] __kmalloc_track_caller+0x143/0x340
[ 145.537824] kvasprintf+0x64/0xc0
[ 145.539157] kobject_set_name_vargs+0x1e/0x90
[ 145.540769] kobject_init_and_add+0x5d/0xa0
[ 145.542348] ? lockdep_init_map_waits+0x4d/0x200
[ 145.544092] btrfs_sysfs_add_one_qgroup+0x72/0xa0 [btrfs]
[ 145.545966] add_qgroup_rb+0xb0/0x140 [btrfs]
[ 145.547654] btrfs_create_qgroup+0x80/0xf0 [btrfs]
[ 145.549266] btrfs_ioctl+0x17bd/0x2540 [btrfs]
[ 145.550739] ? handle_mm_fault+0x732/0xa30
[ 145.552305] ? up_read+0x18/0x240
[ 145.553623] ? ksys_ioctl+0x68/0xa0
[ 145.555029] ksys_ioctl+0x68/0xa0
[ 145.556451] __x64_sys_ioctl+0x16/0x20
[ 145.557898] do_syscall_64+0x50/0xe0
[ 145.559206] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 145.560785] RIP: 0033:0x7f13619797b7
[ 145.562035] Code: Bad RIP value.
[ 145.563248] RSP: 002b:00007fff11e80428 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
[ 145.566129] RAX: ffffffffffffffda RBX: 00007fff11e805e8 RCX: 00007f13619797b7
[ 145.568255] RDX: 00007fff11e80440 RSI: 000000004010942a RDI: 0000000000000003
[ 145.570208] RBP: 0000000000000001 R08: 000055cc5da232a0 R09: 00007f1361a43a40
[ 145.572201] R10: fffffffffffff486 R11: 0000000000000206 R12: 00007fff11e80440
[ 145.574242] R13: 0000000000000003 R14: 0000000000000000 R15: 000055cc5d9d31ac
