pkg/report: improve some titles (#1332)

* pkg/report: improve BUG: MAX_STACK_TRACE_ENTRIES titles

* pkg/report: improve refcount bug titles

8 files changed, 433 insertions, 2 deletions

diff --git a/pkg/report/linux.go b/pkg/report/linux.go
index 99e348365..991bbcaee 100644
--- a/pkg/report/linux.go
+++ b/pkg/report/linux.go
@@ -761,6 +761,11 @@ var linuxStackParams = &stackParams{
 		"flush_work",
 		"__cancel_work_timer",
 		"cancel_work_sync",
+		"flush_workqueue",
+		"drain_workqueue",
+		"destroy_workqueue",
+		"get_device_parent",
+		"device_add",
 	},
 	corruptedLines: []*regexp.Regexp{
 		// Fault injection stacks are frequently intermixed with crash reports.
@@ -959,6 +964,11 @@ var linuxOopses = []*oops{
 				},
 			},
 			{
+				title: compile("BUG: MAX_STACK_TRACE_ENTRIES too low!"),
+				fmt:   "BUG: MAX_STACK_TRACE_ENTRIES too low in %[1]v",
+				stack: warningStackFmt("save_trace", "mark_lock"),
+			},
+			{
 				title: compile("BUG: using __this_cpu_([a-z_]+)\\(\\) in preemptible"),
 				fmt:   "BUG: using __this_cpu_%[1]v() in preemptible code in %[2]v",
 				stack: &stackFmt{
@@ -1045,7 +1055,7 @@ var linuxOopses = []*oops{
 			{
 				title: compile("WARNING: .*lib/refcount\\.c.* refcount_"),
 				fmt:   "WARNING: refcount bug in %[1]v",
-				stack: warningStackFmt("refcount"),
+				stack: warningStackFmt("refcount", "kobject_"),
 			},
 			{
 				title: compile("WARNING: .*kernel/locking/lockdep\\.c.*lock_"),
diff --git a/pkg/report/testdata/linux/report/215 b/pkg/report/testdata/linux/report/215
index ffe9c3f73..0dd634d7f 100644
--- a/pkg/report/testdata/linux/report/215
+++ b/pkg/report/testdata/linux/report/215
@@ -1,4 +1,4 @@
-TITLE: general protection fault in drain_workqueue
+TITLE: general protection fault in ucma_close
 
 [   52.099632] kasan: GPF could be caused by NULL-ptr deref or user memory access
 [   52.106982] general protection fault: 0000 [#1] SMP KASAN
diff --git a/pkg/report/testdata/linux/report/403 b/pkg/report/testdata/linux/report/403
new file mode 100644
index 000000000..b287a56ba
--- /dev/null
+++ b/pkg/report/testdata/linux/report/403
@@ -0,0 +1,47 @@
+TITLE: BUG: MAX_STACK_TRACE_ENTRIES too low in ucma_close
+
+[  185.416858][  T809] BUG: MAX_STACK_TRACE_ENTRIES too low!
+[  185.422408][  T809] turning off the locking correctness validator.
+[  185.428702][  T809] CPU: 1 PID: 809 Comm: syz-executor986 Not tainted 5.1.0-rc2+ #44
+[  185.436697][  T809] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+[  185.446719][  T809] Call Trace:
+[  185.449986][  T809]  dump_stack+0x172/0x1f0
+[  185.454359][  T809]  save_trace.cold+0x14/0x19
+[  185.458944][  T809]  mark_lock+0x2fb/0x1380
+[  185.463242][  T809]  ? is_bpf_text_address+0xac/0x170
+[  185.468401][  T809]  ? print_shortest_lock_dependencies+0x90/0x90
+[  185.474608][  T809]  __lock_acquire+0x1317/0x3fb0
+[  185.479423][  T809]  ? lock_downgrade+0x880/0x880
+[  185.484239][  T809]  ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
+[  185.490438][  T809]  ? is_dynamic_key+0x1c0/0x1c0
+[  185.495251][  T809]  ? mark_held_locks+0xf0/0xf0
+[  185.499975][  T809]  ? __lock_acquire+0x548/0x3fb0
+[  185.504875][  T809]  ? __kernel_text_address+0xd/0x40
+[  185.510033][  T809]  ? unwind_get_return_address+0x61/0xa0
+[  185.515627][  T809]  lock_acquire+0x16f/0x3f0
+[  185.520095][  T809]  ? flush_workqueue+0xf7/0x14c0
+[  185.525009][  T809]  flush_workqueue+0x126/0x14c0
+[  185.529824][  T809]  ? flush_workqueue+0xf7/0x14c0
+[  185.534722][  T809]  ? lock_downgrade+0x880/0x880
+[  185.539537][  T809]  ? pwq_unbound_release_workfn+0x2f0/0x2f0
+[  185.545395][  T809]  ? wait_for_completion+0x440/0x440
+[  185.550686][  T809]  ? mutex_trylock+0x1e0/0x1e0
+[  185.555425][  T809]  ? ucma_free_ctx+0xb90/0xb90
+[  185.560165][  T809]  drain_workqueue+0x1b4/0x470
+[  185.564900][  T809]  ? drain_workqueue+0x1b4/0x470
+[  185.569804][  T809]  ? fsnotify+0x811/0xbc0
+[  185.574102][  T809]  ? ucma_free_ctx+0xb90/0xb90
+[  185.578862][  T809]  destroy_workqueue+0x21/0x700
+[  185.583692][  T809]  ? ucma_free_ctx+0xb90/0xb90
+[  185.588414][  T809]  ucma_close+0x289/0x320
+[  185.592706][  T809]  ? __might_sleep+0x95/0x190
+[  185.597343][  T809]  ? ucma_free_ctx+0xb90/0xb90
+[  185.602069][  T809]  __fput+0x2e5/0x8d0
+[  185.606015][  T809]  ____fput+0x16/0x20
+[  185.609956][  T809]  task_work_run+0x14a/0x1c0
+[  185.614530][  T809]  exit_to_usermode_loop+0x273/0x2c0
+[  185.619778][  T809]  do_syscall_64+0x52d/0x610
+[  185.624342][  T809]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
+[  185.630195][  T809] RIP: 0033:0x400ef0
+[  185.634068][  T809] Code: 01 f0 ff ff 0f 83 20 0c 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d dd 17 2d 00 00 75 14 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 f4 0b 00 00 c3 48 83 ec 08 e8 5a 01 00 00
+[  185.653672][  T809] RSP: 002b:00007ffecc78cbb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
diff --git a/pkg/report/testdata/linux/report/404 b/pkg/report/testdata/linux/report/404
new file mode 100644
index 000000000..e7163a884
--- /dev/null
+++ b/pkg/report/testdata/linux/report/404
@@ -0,0 +1,55 @@
+TITLE: BUG: MAX_STACK_TRACE_ENTRIES too low in scsi_remove_host
+
+[ 3167.402179][T32668] BUG: MAX_STACK_TRACE_ENTRIES too low!
+[ 3167.407738][T32668] turning off the locking correctness validator.
+[ 3167.414046][T32668] CPU: 1 PID: 32668 Comm: kworker/1:1 Not tainted 5.2.0-rc6+ #15
+[ 3167.421733][T32668] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+[ 3167.431773][T32668] Workqueue: usb_hub_wq hub_event
+[ 3167.436772][T32668] Call Trace:
+[ 3167.440048][T32668]  dump_stack+0xca/0x13e
+[ 3167.444285][T32668]  save_trace.isra.0.cold+0x11/0x19
+[ 3167.449472][T32668]  mark_lock+0x2b9/0x10c0
+[ 3167.453779][T32668]  ? print_shortest_lock_dependencies+0x80/0x80
+[ 3167.460005][T32668]  __lock_acquire+0x54a/0x5340
+[ 3167.464743][T32668]  ? __lock_acquire+0x54a/0x5340
+[ 3167.469659][T32668]  ? find_held_lock+0x2d/0x110
+[ 3167.474399][T32668]  ? __free_object+0xdd/0x1e0
+[ 3167.479050][T32668]  ? mark_held_locks+0xe0/0xe0
+[ 3167.483785][T32668]  ? mark_held_locks+0xe0/0xe0
+[ 3167.488526][T32668]  ? _raw_spin_unlock_irqrestore+0x3e/0x50
+[ 3167.494305][T32668]  ? lockdep_hardirqs_on+0x379/0x580
+[ 3167.499577][T32668]  ? __lock_acquire+0x54a/0x5340
+[ 3167.504577][T32668]  lock_acquire+0x100/0x2b0
+[ 3167.509055][T32668]  ? flush_workqueue+0xf7/0x14c0
+[ 3167.513964][T32668]  flush_workqueue+0x126/0x14c0
+[ 3167.518796][T32668]  ? flush_workqueue+0xf7/0x14c0
+[ 3167.523705][T32668]  ? mark_held_locks+0xe0/0xe0
+[ 3167.528449][T32668]  ? __mutex_lock+0x3a2/0x12b0
+[ 3167.533185][T32668]  ? find_held_lock+0x2d/0x110
+[ 3167.537923][T32668]  ? __pm_runtime_resume+0x111/0x180
+[ 3167.543180][T32668]  ? max_active_store+0x120/0x120
+[ 3167.548178][T32668]  ? _raw_spin_unlock_irqrestore+0x3e/0x50
+[ 3167.553973][T32668]  ? lockdep_hardirqs_on+0x379/0x580
+[ 3167.559232][T32668]  ? scsi_remove_host+0x12d/0x360
+[ 3167.564229][T32668]  scsi_remove_host+0x12d/0x360
+[ 3167.569055][T32668]  usb_stor_disconnect+0x106/0x230
+[ 3167.574160][T32668]  usb_unbind_interface+0x1bd/0x8a0
+[ 3167.579330][T32668]  ? usb_autoresume_device+0x60/0x60
+[ 3167.584590][T32668]  device_release_driver_internal+0x404/0x4c0
+[ 3167.590627][T32668]  bus_remove_device+0x2dc/0x4a0
+[ 3167.595541][T32668]  device_del+0x460/0xb80
+[ 3167.599845][T32668]  ? __device_links_no_driver+0x240/0x240
+[ 3167.605539][T32668]  ? usb_remove_ep_devs+0x3e/0x80
+[ 3167.610536][T32668]  ? remove_intf_ep_devs+0x13f/0x1d0
+[ 3167.615794][T32668]  usb_disable_device+0x211/0x690
+[ 3167.620795][T32668]  usb_disconnect+0x284/0x830
+[ 3167.625457][T32668]  hub_event+0x13bd/0x3550
+[ 3167.629848][T32668]  ? hub_port_debounce+0x260/0x260
+[ 3167.634934][T32668]  process_one_work+0x905/0x1570
+[ 3167.639851][T32668]  ? pwq_dec_nr_in_flight+0x310/0x310
+[ 3167.645196][T32668]  ? do_raw_spin_lock+0x11a/0x280
+[ 3167.650210][T32668]  worker_thread+0x96/0xe20
+[ 3167.654704][T32668]  ? process_one_work+0x1570/0x1570
+[ 3167.659881][T32668]  kthread+0x30b/0x410
+[ 3167.663925][T32668]  ? kthread_park+0x1a0/0x1a0
+[ 3167.668574][T32668]  ret_from_fork+0x24/0x30
diff --git a/pkg/report/testdata/linux/report/405 b/pkg/report/testdata/linux/report/405
new file mode 100644
index 000000000..e36dfcfd6
--- /dev/null
+++ b/pkg/report/testdata/linux/report/405
@@ -0,0 +1,73 @@
+TITLE: WARNING: refcount bug in cdev_get
+
+[ 1191.409330][ T6711] ------------[ cut here ]------------
+[ 1191.414962][ T6711] refcount_t: increment on 0; use-after-free.
+[ 1191.421477][ T6711] WARNING: CPU: 1 PID: 6711 at lib/refcount.c:156 refcount_inc_checked+0x59/0x60
+[ 1191.430701][ T6711] Kernel panic - not syncing: panic_on_warn set ...
+[ 1191.437319][ T6711] CPU: 1 PID: 6711 Comm: syz-executor.0 Not tainted 5.3.0-rc2+ #25
+[ 1191.446758][ T6711] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+[ 1191.456844][ T6711] Call Trace:
+[ 1191.460354][ T6711]  dump_stack+0xca/0x13e
+[ 1191.464733][ T6711]  ? refcount_inc_not_zero_checked+0x170/0x1e0
+[ 1191.470914][ T6711]  panic+0x2a3/0x6da
+[ 1191.474838][ T6711]  ? add_taint.cold+0x16/0x16
+[ 1191.479610][ T6711]  ? __probe_kernel_read+0x188/0x1d0
+[ 1191.485106][ T6711]  ? __warn.cold+0x5/0x4a
+[ 1191.489637][ T6711]  ? __warn+0xe3/0x1e0
+[ 1191.493740][ T6711]  ? refcount_inc_checked+0x59/0x60
+[ 1191.498954][ T6711]  __warn.cold+0x20/0x4a
+[ 1191.503221][ T6711]  ? refcount_inc_checked+0x59/0x60
+[ 1191.508433][ T6711]  report_bug+0x262/0x2a0
+[ 1191.512960][ T6711]  do_error_trap+0x12b/0x1e0
+[ 1191.517566][ T6711]  ? refcount_inc_checked+0x59/0x60
+[ 1191.522782][ T6711]  do_invalid_op+0x32/0x40
+[ 1191.527314][ T6711]  ? refcount_inc_checked+0x59/0x60
+[ 1191.532585][ T6711]  invalid_op+0x23/0x30
+[ 1191.536851][ T6711] RIP: 0010:refcount_inc_checked+0x59/0x60
+[ 1191.542859][ T6711] Code: 1d 78 8f a7 05 31 ff 89 de e8 53 49 5d ff 84 db 75 e0 e8 1a 48 5d ff 48 c7 c7 40 c1 da 85 c6 05 58 8f a7 05 01 e8 3c 19 33 ff <0f> 0b eb c4 90 90 90 41 57 41 56 41 55 49 89 fd 41 54 55 48 89 f5
+[ 1191.562935][ T6711] RSP: 0018:ffff8881c853f958 EFLAGS: 00010282
+[ 1191.569024][ T6711] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
+[ 1191.577101][ T6711] RDX: 0000000000000000 RSI: ffffffff8128a0fd RDI: ffffed10390a7f1d
+[ 1191.585205][ T6711] RBP: ffff8881d660b938 R08: ffff8881d55f9800 R09: fffffbfff11acd9c
+[ 1191.593190][ T6711] R10: fffffbfff11acd9b R11: ffffffff88d66cdf R12: ffff8881d660b900
+[ 1191.601180][ T6711] R13: 0000000000000000 R14: ffff8881ca2bbc20 R15: ffff8881c8a391fc
+[ 1191.609481][ T6711]  ? vprintk_func+0x7d/0x113
+[ 1191.614095][ T6711]  ? refcount_inc_checked+0x59/0x60
+[ 1191.619471][ T6711]  kobject_get+0x62/0xc0
+[ 1191.623771][ T6711]  cdev_get+0x5c/0xb0
+[ 1191.627873][ T6711]  chrdev_open+0xaa/0x5c0
+[ 1191.632370][ T6711]  ? rwlock_bug.part.0+0x90/0x90
+[ 1191.637480][ T6711]  ? cdev_put.part.0+0x50/0x50
+[ 1191.642500][ T6711]  do_dentry_open+0x494/0x1120
+[ 1191.647333][ T6711]  ? cdev_put.part.0+0x50/0x50
+[ 1191.652114][ T6711]  ? chmod_common+0x3c0/0x3c0
+[ 1191.656956][ T6711]  ? inode_permission+0xbe/0x3a0
+[ 1191.661919][ T6711]  path_openat+0x1430/0x3f50
+[ 1191.666573][ T6711]  ? save_stack+0x1b/0x80
+[ 1191.670919][ T6711]  ? do_sys_open+0x294/0x580
+[ 1191.675682][ T6711]  ? do_syscall_64+0xb7/0x580
+[ 1191.680373][ T6711]  ? path_lookupat.isra.0+0x8d0/0x8d0
+[ 1191.685760][ T6711]  ? __lock_acquire+0x145e/0x3b50
+[ 1191.691048][ T6711]  do_filp_open+0x1a1/0x280
+[ 1191.695649][ T6711]  ? may_open_dev+0xf0/0xf0
+[ 1191.700186][ T6711]  ? __alloc_fd+0x46d/0x600
+[ 1191.704706][ T6711]  ? do_raw_spin_lock+0x11a/0x280
+[ 1191.709740][ T6711]  ? do_raw_spin_unlock+0x50/0x220
+[ 1191.715066][ T6711]  ? _raw_spin_unlock+0x1f/0x30
+[ 1191.719942][ T6711]  ? __alloc_fd+0x46d/0x600
+[ 1191.724460][ T6711]  do_sys_open+0x3c0/0x580
+[ 1191.728893][ T6711]  ? filp_open+0x70/0x70
+[ 1191.733238][ T6711]  ? __ia32_sys_clock_settime+0x260/0x260
+[ 1191.739119][ T6711]  ? trace_hardirqs_off_caller+0x55/0x1e0
+[ 1191.744853][ T6711]  do_syscall_64+0xb7/0x580
+[ 1191.749387][ T6711]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
+[ 1191.755550][ T6711] RIP: 0033:0x413711
+[ 1191.759460][ T6711] Code: 75 14 b8 02 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 19 00 00 c3 48 83 ec 08 e8 0a fa ff ff 48 89 04 24 b8 02 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01
+[ 1191.779203][ T6711] RSP: 002b:00007fcd70ca27a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002
+[ 1191.787902][ T6711] RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000413711
+[ 1191.795895][ T6711] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fcd70ca2850
+[ 1191.803887][ T6711] RBP: 000000000075bf20 R08: 000000000000000f R09: 0000000000000000
+[ 1191.812072][ T6711] R10: 0000000000000000 R11: 0000000000000293 R12: 00007fcd70ca36d4
+[ 1191.820263][ T6711] R13: 00000000004c8bc7 R14: 00000000004dfa58 R15: 00000000ffffffff
+[ 1191.829087][ T6711] Kernel Offset: disabled
+[ 1191.833487][ T6711] Rebooting in 86400 seconds..
diff --git a/pkg/report/testdata/linux/report/406 b/pkg/report/testdata/linux/report/406
new file mode 100644
index 000000000..ff7236ac7
--- /dev/null
+++ b/pkg/report/testdata/linux/report/406
@@ -0,0 +1,74 @@
+TITLE: WARNING: refcount bug in hci_register_dev
+
+[   83.882482][T10363] ------------[ cut here ]------------
+[   83.894883][T10363] refcount_t: increment on 0; use-after-free.
+[   83.901740][T10363] WARNING: CPU: 0 PID: 10363 at lib/refcount.c:156 refcount_inc_checked+0x61/0x70
+[   83.911146][T10363] Kernel panic - not syncing: panic_on_warn set ...
+[   83.917719][T10363] CPU: 0 PID: 10363 Comm: syz-executor494 Not tainted 5.3.0-rc2+ #112
+[   83.925858][T10363] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+[   83.936006][T10363] Call Trace:
+[   83.939303][T10363]  dump_stack+0x172/0x1f0
+[   83.943651][T10363]  ? refcount_inc_not_zero_checked+0x180/0x200
+[   83.949907][T10363]  panic+0x2dc/0x755
+[   83.954073][T10363]  ? add_taint.cold+0x16/0x16
+[   83.958747][T10363]  ? __kasan_check_write+0x14/0x20
+[   83.963852][T10363]  ? __warn.cold+0x5/0x4c
+[   83.968333][T10363]  ? __warn+0xe7/0x1e0
+[   83.972417][T10363]  ? refcount_inc_checked+0x61/0x70
+[   83.977794][T10363]  __warn.cold+0x20/0x4c
+[   83.982051][T10363]  ? refcount_inc_checked+0x61/0x70
+[   83.987235][T10363]  report_bug+0x263/0x2b0
+[   83.991664][T10363]  do_error_trap+0x11b/0x200
+[   83.996328][T10363]  do_invalid_op+0x37/0x50
+[   84.000735][T10363]  ? refcount_inc_checked+0x61/0x70
+[   84.005920][T10363]  invalid_op+0x23/0x30
+[   84.010085][T10363] RIP: 0010:refcount_inc_checked+0x61/0x70
+[   84.015875][T10363] Code: 1d 5e 90 64 06 31 ff 89 de e8 eb 99 35 fe 84 db 75 dd e8 a2 98 35 fe 48 c7 c7 80 03 c6 87 c6 05 3e 90 64 06 01 e8 57 05 07 fe <0f> 0b eb c1 90 90 90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41
+[   84.035461][T10363] RSP: 0018:ffff8880a818f8f8 EFLAGS: 00010286
+[   84.041508][T10363] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
+[   84.049467][T10363] RDX: 0000000000000000 RSI: ffffffff815c5216 RDI: ffffed1015031f11
+[   84.057421][T10363] RBP: ffff8880a818f908 R08: ffff8880a7e70300 R09: ffffed1015d04101
+[   84.065383][T10363] R10: ffffed1015d04100 R11: ffff8880ae820807 R12: ffff88821adec338
+[   84.073527][T10363] R13: ffff888094299820 R14: ffff888094299818 R15: ffff88821adec2b8
+[   84.081510][T10363]  ? vprintk_func+0x86/0x189
+[   84.086215][T10363]  ? refcount_inc_checked+0x61/0x70
+[   84.091419][T10363]  kobject_get+0x66/0xc0
+[   84.095671][T10363]  kobject_add_internal+0x14f/0x380
+[   84.100884][T10363]  ? kfree_const+0x5e/0x70
+[   84.105300][T10363]  kobject_add+0x150/0x1c0
+[   84.109731][T10363]  ? kset_create_and_add+0x1a0/0x1a0
+[   84.115124][T10363]  ? kasan_kmalloc+0x9/0x10
+[   84.119630][T10363]  ? kmem_cache_alloc_trace+0x346/0x790
+[   84.125165][T10363]  get_device_parent.isra.0+0x413/0x560
+[   84.130695][T10363]  device_add+0x2df/0x17a0
+[   84.135098][T10363]  ? get_device_parent.isra.0+0x560/0x560
+[   84.140797][T10363]  ? up_write+0x9d/0x280
+[   84.145023][T10363]  hci_register_dev+0x2e8/0x8f0
+[   84.149891][T10363]  __vhci_create_device+0x2c5/0x5d0
+[   84.155097][T10363]  vhci_write+0x2d0/0x470
+[   84.159410][T10363]  new_sync_write+0x4d3/0x770
+[   84.164079][T10363]  ? new_sync_read+0x800/0x800
+[   84.168857][T10363]  ? common_file_perm+0x238/0x720
+[   84.173877][T10363]  ? __kasan_check_read+0x11/0x20
+[   84.178900][T10363]  ? apparmor_file_permission+0x25/0x30
+[   84.184451][T10363]  ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
+[   84.190690][T10363]  ? security_file_permission+0x8f/0x380
+[   84.196306][T10363]  __vfs_write+0xe1/0x110
+[   84.200620][T10363]  vfs_write+0x268/0x5d0
+[   84.204844][T10363]  ksys_write+0x14f/0x290
+[   84.209193][T10363]  ? __ia32_sys_read+0xb0/0xb0
+[   84.213943][T10363]  ? __sanitizer_cov_trace_const_cmp4+0x16/0x20
+[   84.220179][T10363]  ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe
+[   84.226325][T10363]  __x64_sys_write+0x73/0xb0
+[   84.230926][T10363]  do_syscall_64+0xfd/0x6a0
+[   84.235415][T10363]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
+[   84.241327][T10363] RIP: 0033:0x441279
+[   84.245225][T10363] Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
+[   84.264855][T10363] RSP: 002b:00007fffdebca038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
+[   84.273275][T10363] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441279
+[   84.281251][T10363] RDX: 0000000000000002 RSI: 0000000020000000 RDI: 0000000000000003
+[   84.289237][T10363] RBP: 0000000000014777 R08: 00000000004002c8 R09: 00000000004002c8
+[   84.297234][T10363] R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000401ff0
+[   84.305317][T10363] R13: 0000000000402080 R14: 0000000000000000 R15: 0000000000000000
+[   84.314420][T10363] Kernel Offset: disabled
+[   84.318949][T10363] Rebooting in 86400 seconds..
diff --git a/pkg/report/testdata/linux/report/407 b/pkg/report/testdata/linux/report/407
new file mode 100644
index 000000000..d2b8a15b9
--- /dev/null
+++ b/pkg/report/testdata/linux/report/407
@@ -0,0 +1,90 @@
+TITLE: WARNING: kobject bug in netdev_register_kobject
+
+[   24.413160] ------------[ cut here ]------------
+[   24.417920] WARNING: CPU: 0 PID: 1928 at lib/kobject.c:244 kobject_add_internal.cold.13+0xc8/0xe2
+[   24.426901] Kernel panic - not syncing: panic_on_warn set ...
+[   24.426901] 
+[   24.434238] CPU: 0 PID: 1928 Comm: syzkaller927371 Not tainted 4.14.31+ #2
+[   24.441222] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+[   24.450548] Call Trace:
+[   24.453109]  dump_stack+0x114/0x1cf
+[   24.456710]  ? show_regs_print_info+0x6a/0x6a
+[   24.461177]  ? _atomic_dec_and_lock+0x171/0x171
+[   24.465817]  ? kobject_add_internal.cold.13+0xc8/0xe2
+[   24.470981]  panic+0x1bb/0x3a0
+[   24.474164]  ? add_taint.cold.6+0x16/0x16
+[   24.478290]  ? kobject_add_internal.cold.13+0xc8/0xe2
+[   24.483451]  __warn.cold.9+0x149/0x186
+[   24.487317]  ? kobject_add_internal.cold.13+0xc8/0xe2
+[   24.492485]  report_bug+0x1f7/0x272
+[   24.496091]  do_error_trap+0x1c1/0x430
+[   24.499957]  ? vprintk_emit+0x23b/0x4e0
+[   24.503905]  ? math_error+0x3c0/0x3c0
+[   24.507680]  ? vprintk_emit+0x200/0x4e0
+[   24.511635]  ? trace_hardirqs_off_thunk+0x1a/0x1c
+[   24.516451]  do_invalid_op+0x20/0x30
+[   24.520145]  invalid_op+0x1b/0x40
+[   24.523599] RIP: 0010:kobject_add_internal.cold.13+0xc8/0xe2
+[   24.529380] RSP: 0018:ffff8801d28175c0 EFLAGS: 00010286
+[   24.534717] RAX: 0000000000000043 RBX: ffff8801d2c9c558 RCX: 0000000000000000
+[   24.541961] RDX: 0000000000000043 RSI: ffff8801dba1e3b8 RDI: ffffed003a502eae
+[   24.549202] RBP: ffff8801d28176b8 R08: ffff8801d4f753d8 R09: 0000000000000006
+[   24.556446] R10: ffff8801d4f74b40 R11: 0000000000000000 R12: ffffffff83adc840
+[   24.563689] R13: 00000000fffffff4 R14: ffff8801d777f888 R15: ffff8801d2c9c560
+[   24.570951]  ? kobj_ns_type_registered+0x50/0x50
+[   24.575678]  ? lock_release+0x8b0/0x8b0
+[   24.579626]  ? __raw_spin_lock_init+0x32/0x100
+[   24.584183]  ? klist_init+0xf8/0x1c0
+[   24.587873]  ? refcount_inc_not_zero+0xfd/0x170
+[   24.592529]  kobject_add+0x11f/0x180
+[   24.596215]  ? kset_create_and_add+0x170/0x170
+[   24.600772]  ? mutex_unlock+0x12/0x20
+[   24.604548]  device_add+0x390/0x1610
+[   24.608236]  ? dev_set_name+0xa9/0xd0
+[   24.612032]  ? device_private_init+0x240/0x240
+[   24.616591]  ? rtnl_is_locked+0x59/0xb0
+[   24.620537]  ? rtnl_kfree_skbs+0x70/0x70
+[   24.624573]  netdev_register_kobject+0x128/0x2ec
+[   24.629304]  register_netdevice+0x9ba/0xf20
+[   24.633602]  ? netdev_change_features+0x100/0x100
+[   24.638419]  ? __raw_spin_lock_init+0x21/0x100
+[   24.642973]  ? round_jiffies_up+0xfc/0x140
+[   24.647200]  ? __round_jiffies_up_relative+0x190/0x190
+[   24.652454]  __tun_chr_ioctl+0x2307/0x3e40
+[   24.656666]  ? tun_chr_read_iter+0x1e0/0x1e0
+[   24.661065]  ? get_pid_task+0xc5/0x140
+[   24.664947]  ? proc_fail_nth_write+0xbd/0x270
+[   24.669416]  ? proc_task_getattr+0x190/0x190
+[   24.673807]  ? find_held_lock+0x36/0x1c0
+[   24.677844]  ? vfs_write+0x266/0x500
+[   24.681531]  ? lock_downgrade+0x740/0x740
+[   24.685658]  ? kernel_read+0x130/0x130
+[   24.689533]  tun_chr_ioctl+0x2f/0x40
+[   24.693227]  ? tun_chr_compat_ioctl+0x40/0x40
+[   24.698050]  do_vfs_ioctl+0x1b7/0x15d0
+[   24.701912]  ? ioctl_preallocate+0x2c0/0x2c0
+[   24.706295]  ? fget_raw+0x20/0x20
+[   24.709723]  ? __sb_end_write+0xa5/0xd0
+[   24.713672]  ? vfs_write+0x222/0x500
+[   24.717358]  ? SyS_write+0x179/0x230
+[   24.721051]  ? security_file_ioctl+0x94/0xc0
+[   24.725431]  SyS_ioctl+0x94/0xc0
+[   24.728770]  ? do_vfs_ioctl+0x15d0/0x15d0
+[   24.732890]  do_syscall_64+0x251/0x6d0
+[   24.736752]  ? trace_hardirqs_on_thunk+0x1a/0x1c
+[   24.741482]  ? syscall_return_slowpath+0x330/0x330
+[   24.746385]  ? syscall_return_slowpath+0x217/0x330
+[   24.751308]  ? entry_SYSCALL_64_after_hwframe+0x52/0xb7
+[   24.756644]  ? trace_hardirqs_off_thunk+0x1a/0x1c
+[   24.761462]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
+[   24.766625] RIP: 0033:0x444179
+[   24.769792] RSP: 002b:00007ffcebc3f4b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
+[   24.777473] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444179
+[   24.784720] RDX: 0000000020000180 RSI: 00000000400454ca RDI: 0000000000000003
+[   24.791963] RBP: 00000000006cf018 R08: 0000000000000001 R09: 00007ffcebc30035
+[   24.799214] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
+[   24.806466] R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000
+[   24.814408] Dumping ftrace buffer:
+[   24.818034]    (ftrace buffer empty)
+[   24.822300] Kernel Offset: disabled
+[   24.825915] Rebooting in 86400 seconds..
diff --git a/pkg/report/testdata/linux/report/408 b/pkg/report/testdata/linux/report/408
new file mode 100644
index 000000000..f66029a1d
--- /dev/null
+++ b/pkg/report/testdata/linux/report/408
@@ -0,0 +1,82 @@
+TITLE: WARNING: refcount bug in input_register_device
+
+[  116.957737] ------------[ cut here ]------------
+[  116.963070] refcount_t: increment on 0; use-after-free.
+[  116.968562] WARNING: CPU: 1 PID: 4353 at lib/refcount.c:153 refcount_inc+0x47/0x50
+[  116.976271] Kernel panic - not syncing: panic_on_warn set ...
+[  116.976271] 
+[  116.983645] CPU: 1 PID: 4353 Comm: syz-executor5 Not tainted 4.14.89+ #6
+[  116.990488] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
+[  116.999846] Call Trace:
+[  117.002449]  dump_stack+0x114/0x1cf
+[  117.006086]  ? show_regs_print_info+0x6a/0x6a
+[  117.010593]  ? _atomic_dec_and_lock+0x171/0x171
+[  117.015311]  ? do_raw_spin_trylock+0x190/0x190
+[  117.019907]  ? refcount_inc+0x47/0x50
+[  117.023720]  panic+0x1bb/0x3a0
+[  117.026918]  ? add_taint.cold.6+0x16/0x16
+[  117.031077]  ? __warn.cold.9+0x5/0x46
+[  117.034887]  ? refcount_inc+0x47/0x50
+[  117.038733]  __warn.cold.9+0x20/0x46
+[  117.042485]  ? refcount_inc+0x47/0x50
+[  117.046293]  report_bug+0x1fd/0x272
+[  117.049928]  do_error_trap+0x1c2/0x430
+[  117.053825]  ? math_error+0x3e0/0x3e0
+[  117.057636]  ? vprintk_func+0x63/0xea
+[  117.061440]  ? printk+0xa3/0xbf
+[  117.064735]  ? show_regs_print_info+0x6a/0x6a
+[  117.069235]  ? trace_hardirqs_off_thunk+0x1a/0x1c
+[  117.074091]  do_invalid_op+0x20/0x30
+[  117.077813]  invalid_op+0x1b/0x40
+[  117.081277] RIP: 0010:refcount_inc+0x47/0x50
+[  117.085913] RSP: 0018:ffff8881c966f878 EFLAGS: 00010282
+[  117.085949] RAX: 000000000000002b RBX: ffff8881d40fa500 RCX: ffffc9000207d000
+[  117.085958] RDX: 00000000000030e2 RSI: ffffffff812d86d3 RDI: ffff8881c966f3c0
+[  117.085966] RBP: ffff8881c966f880 R08: ffff8881a65421c8 R09: 0000000000000006
+[  117.085974] R10: 0000000000000000 R11: ffff8881a6541900 R12: dffffc0000000000
+[  117.085981] R13: ffff8881d40fa4d0 R14: ffff8881d2b7bfc0 R15: ffff8881da3217c8
+[  117.086009]  ? vprintk_func+0x63/0xea
+[  117.131534]  ? refcount_inc+0x47/0x50
+[  117.135349]  kobject_get+0x50/0xa0
+[  117.139493]  get_device_parent.isra.27+0x3e0/0x5a0
+[  117.144452]  device_add+0x301/0x1620
+[  117.144471]  ? device_private_init+0x240/0x240
+[  117.144502]  ? __kmalloc+0x17f/0x380
+[  117.144520]  input_register_device+0x660/0xbb0
+[  117.144546]  ? devm_input_allocate_device+0x130/0x130
+[  117.144559]  ? lock_release+0x920/0x920
+[  117.144577]  uinput_ioctl_handler.isra.9+0x9f3/0x1fe0
+[  117.144591]  ? uinput_request_submit.part.8+0x290/0x290
+[  117.144613]  ? __fget+0x37b/0x580
+[  117.144622]  ? lock_downgrade+0x700/0x700
+[  117.144640]  ? expand_files.part.8+0x850/0x850
+[  117.144656]  ? static_key_enable.constprop.102+0x1b0/0x1b0
+[  117.144672]  ? uinput_compat_ioctl+0x80/0x80
+[  117.144681]  uinput_ioctl+0x51/0x60
+[  117.144695]  do_vfs_ioctl+0x1a4/0x1540
+[  117.144713]  ? ioctl_preallocate+0x2c0/0x2c0
+[  117.144726]  ? fget_raw+0x20/0x20
+[  117.144739]  ? put_timespec64+0x103/0x190
+[  117.144749]  ? nsecs_to_jiffies+0x30/0x30
+[  117.144788]  ? SyS_clock_gettime+0x111/0x1c0
+[  117.144802]  ? security_file_ioctl+0x94/0xc0
+[  117.144818]  SyS_ioctl+0x94/0xc0
+[  117.144830]  ? do_vfs_ioctl+0x1540/0x1540
+[  117.144843]  do_syscall_64+0x251/0x750
+[  117.144857]  ? copy_overflow+0x20/0x20
+[  117.144868]  ? syscall_return_slowpath+0x3b0/0x3b0
+[  117.144881]  ? syscall_return_slowpath+0x220/0x3b0
+[  117.144893]  ? __switch_to_asm+0x34/0x70
+[  117.144906]  ? prepare_exit_to_usermode+0x270/0x270
+[  117.144920]  ? entry_SYSCALL_64_after_hwframe+0x52/0xb7
+[  117.144936]  ? trace_hardirqs_off_thunk+0x1a/0x1c
+[  117.144956]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
+[  117.144964] RIP: 0033:0x457669
+[  117.144970] RSP: 002b:00007fb14c000c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
+[  117.144982] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457669
+[  117.144989] RDX: 0000000000000000 RSI: 0000000000005501 RDI: 0000000000000004
+[  117.144995] RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
+[  117.145003] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb14c0016d4
+[  117.145010] R13: 00000000004c17af R14: 00000000004d3390 R15: 00000000ffffffff
+[  117.146088] Kernel Offset: disabled
+[  117.336935] Rebooting in 86400 seconds..