bisecting fixing commit since da690031a5d6d50a361e3f19f3eeabd086a6f20d
building syzkaller on 4a77ae0bdc5cd75ebe88ce7c896aae6bbf457a29
testing commit da690031a5d6d50a361e3f19f3eeabd086a6f20d with gcc (GCC) 8.1.0
kernel signature: 45be175f635461b91386358bccfd59aa1aacdc8bbc6c1718ada6eb172cf74d5c
all runs: crashed: BUG: unable to handle kernel NULL pointer dereference in __ext4_journal_get_write_access
testing current HEAD 407ab579637ced6dc32cfb2295afb7259cca4b22
testing commit 407ab579637ced6dc32cfb2295afb7259cca4b22 with gcc (GCC) 8.1.0
kernel signature: 91ede27431468ae43d59daf5710cc2682cab3ae49a4acc395628b5e54b0d322d
run #0: crashed: BUG: sleeping function called from invalid context in sta_info_move_state
run #1: crashed: BUG: sleeping function called from invalid context in sta_info_move_state
run #2: crashed: BUG: sleeping function called from invalid context in sta_info_move_state
run #3: OK
run #4: OK
run #5: OK
run #6: OK
run #7: OK
run #8: OK
run #9: OK
revisions tested: 2, total time: 24m20.05090258s (build: 10m33.199220753s, test: 13m14.616388351s)
the crash still happens on HEAD
commit msg: Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
crash: BUG: sleeping function called from invalid context in sta_info_move_state
BUG: sleeping function called from invalid context at net/mac80211/sta_info.c:1962
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 649, name: kworker/u4:5
4 locks held by kworker/u4:5/649:
 #0: ffff88811f8df138 ((wq_completion)phy7){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline]
 #0: ffff88811f8df138 ((wq_completion)phy7){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff88811f8df138 ((wq_completion)phy7){+.+.}-{0:0}, at: process_one_work+0x1e6/0x600 kernel/workqueue.c:2243
 #1: ffffc90002027e70 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline]
 #1: ffffc90002027e70 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #1: ffffc90002027e70 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: process_one_work+0x1e6/0x600 kernel/workqueue.c:2243
 #2: ffff88811fab8d00
 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1021 [inline]
 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x36/0x420 net/mac80211/ibss.c:1683
 #3: ffffffff847fbd40 (rcu_read_lock){....}-{1:2}, at: sta_info_insert_finish net/mac80211/sta_info.c:644 [inline]
 #3: ffffffff847fbd40 (rcu_read_lock){....}-{1:2}, at: sta_info_insert_rcu+0x1c6/0xde0 net/mac80211/sta_info.c:732
Preemption disabled at:
[<ffffffff832bd130>] __mutex_lock_common kernel/locking/mutex.c:955 [inline]
[<ffffffff832bd130>] __mutex_lock+0x70/0x9f0 kernel/locking/mutex.c:1103
CPU: 0 PID: 649 Comm: kworker/u4:5 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: phy7 ieee80211_iface_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xa3/0xc8 lib/dump_stack.c:118
 ___might_sleep.cold.112+0xfb/0x10f kernel/sched/core.c:7298
 sta_info_move_state+0x1a/0x2b0 net/mac80211/sta_info.c:1962
 sta_info_free+0x11/0xd0 net/mac80211/sta_info.c:274
 sta_info_insert_rcu+0xd4/0xde0 net/mac80211/sta_info.c:738
 ieee80211_ibss_finish_sta+0x9e/0x120 net/mac80211/ibss.c:592
 ieee80211_ibss_work+0x10a/0x420 net/mac80211/ibss.c:1700
 process_one_work+0x273/0x600 kernel/workqueue.c:2272
 worker_thread+0x38/0x380 kernel/workqueue.c:2418
 kthread+0x145/0x170 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

=============================
[ BUG: Invalid wait context ]
5.10.0-rc3-syzkaller #0 Tainted: G        W        
-----------------------------
kworker/u4:5/649 is trying to lock:
ffff88811fab29d0 (&local->chanctx_mtx){+.+.}-{3:3}, at: ieee80211_recalc_min_chandef+0x1f/0x90 net/mac80211/util.c:2740
other info that might help us debug this:
context-{4:4}
4 locks held by kworker/u4:5/649:
 #0: ffff88811f8df138 ((wq_completion)phy7){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline]
 #0: ffff88811f8df138 ((wq_completion)phy7){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff88811f8df138 ((wq_completion)phy7){+.+.}-{0:0}, at: process_one_work+0x1e6/0x600 kernel/workqueue.c:2243
 #1: ffffc90002027e70 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline]
 #1: ffffc90002027e70 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #1: ffffc90002027e70 ((work_completion)(&sdata->work)){+.+.}-{0:0}, at: process_one_work+0x1e6/0x600 kernel/workqueue.c:2243
 #2: ffff88811fab8d00 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1021 [inline]
 #2: ffff88811fab8d00 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x36/0x420 net/mac80211/ibss.c:1683
 #3: ffffffff847fbd40 (rcu_read_lock){....}-{1:2}, at: sta_info_insert_finish net/mac80211/sta_info.c:644 [inline]
 #3: ffffffff847fbd40 (rcu_read_lock){....}-{1:2}, at: sta_info_insert_rcu+0x1c6/0xde0 net/mac80211/sta_info.c:732
stack backtrace:
CPU: 1 PID: 649 Comm: kworker/u4:5 Tainted: G        W         5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: phy7 ieee80211_iface_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xa3/0xc8 lib/dump_stack.c:118
 print_lock_invalid_wait_context kernel/locking/lockdep.c:4483 [inline]
 check_wait_context kernel/locking/lockdep.c:4544 [inline]
 __lock_acquire.cold.75+0x29c/0x2b7 kernel/locking/lockdep.c:4781
 lock_acquire+0xf9/0x420 kernel/locking/lockdep.c:5436
 __mutex_lock_common kernel/locking/mutex.c:956 [inline]
 __mutex_lock+0x94/0x9f0 kernel/locking/mutex.c:1103
 ieee80211_recalc_min_chandef+0x1f/0x90 net/mac80211/util.c:2740
 sta_info_move_state+0x140/0x2b0 net/mac80211/sta_info.c:2019
 sta_info_free+0x11/0xd0 net/mac80211/sta_info.c:274
 sta_info_insert_rcu+0xd4/0xde0 net/mac80211/sta_info.c:738
 ieee80211_ibss_finish_sta+0x9e/0x120 net/mac80211/ibss.c:592
 ieee80211_ibss_work+0x10a/0x420 net/mac80211/ibss.c:1700
 process_one_work+0x273/0x600 kernel/workqueue.c:2272
 worker_thread+0x38/0x380 kernel/workqueue.c:2418
 kthread+0x145/0x170 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296