* [syzbot] [trace?] [bpf?] possible deadlock in __mod_timer (4)
@ 2024-09-22 6:39 syzbot
2024-09-26 4:53 ` Steven Rostedt
0 siblings, 1 reply; 3+ messages in thread
From: syzbot @ 2024-09-22 6:39 UTC (permalink / raw)
To: andrii, ast, bpf, daniel, eddyz87, haoluo, john.fastabend, jolsa,
kpsingh, linux-kernel, linux-trace-kernel, martin.lau,
mathieu.desnoyers, mattbobrowski, mhiramat, rostedt, sdf, song,
syzkaller-bugs, yonghong.song
Hello,
syzbot found the following issue on:
HEAD commit: a940d9a43e62 Merge tag 'soc-arm-6.12' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12d1c69f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=44d46e514184cd24
dashboard link: https://syzkaller.appspot.com/bug?extid=83a876aef81c9a485ae8
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11597677980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13cd7500580000
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-a940d9a4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e9929bfe422c/vmlinux-a940d9a4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a6c74ee261ed/bzImage-a940d9a4.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+83a876aef81c9a485ae8@syzkaller.appspotmail.com
FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 1
======================================================
WARNING: possible circular locking dependency detected
6.11.0-syzkaller-03917-ga940d9a43e62 #0 Not tainted
------------------------------------------------------
syz-executor291/5332 is trying to acquire lock:
ffffffff8dda88d8 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
but task is already holding lock:
ffff88806a92a858 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6c1/0xdc0 kernel/time/timer.c:1164
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&base->lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
lock_timer_base+0x5d/0x220 kernel/time/timer.c:1051
__mod_timer+0x426/0xdc0 kernel/time/timer.c:1132
add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
__queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
psi_task_change+0x1b4/0x2e0 kernel/sched/psi.c:913
psi_enqueue kernel/sched/stats.h:143 [inline]
enqueue_task+0x1a5/0x350 kernel/sched/core.c:1975
activate_task kernel/sched/core.c:2009 [inline]
wake_up_new_task+0x5ba/0xd30 kernel/sched/core.c:4689
kernel_clone+0x236/0x960 kernel/fork.c:2812
user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
rest_init+0x23/0x2b0 init/main.c:712
start_kernel+0x3e4/0x4d0 init/main.c:1105
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
common_startup_64+0x13e/0x148
-> #2 (&rq->__lock){-.-.}-{2:2}:
_raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:560
raw_spin_rq_lock kernel/sched/sched.h:1415 [inline]
rq_lock kernel/sched/sched.h:1714 [inline]
task_fork_fair+0x73/0x250 kernel/sched/fair.c:12710
sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4633
copy_process+0x439b/0x8dd0 kernel/fork.c:2483
kernel_clone+0xfd/0x960 kernel/fork.c:2781
user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
rest_init+0x23/0x2b0 init/main.c:712
start_kernel+0x3e4/0x4d0 init/main.c:1105
x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
common_startup_64+0x13e/0x148
-> #1 (&p->pi_lock){-.-.}-{2:2}:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]
try_to_wake_up+0x9a/0x13e0 kernel/sched/core.c:4051
up+0x79/0xb0 kernel/locking/semaphore.c:191
__up_console_sem+0x85/0xe0 kernel/printk/printk.c:343
__console_unlock kernel/printk/printk.c:2844 [inline]
__console_flush_and_unlock kernel/printk/printk.c:3241 [inline]
console_unlock+0x1dc/0x210 kernel/printk/printk.c:3279
vga_remove_vgacon drivers/pci/vgaarb.c:186 [inline]
vga_remove_vgacon+0x90/0xd0 drivers/pci/vgaarb.c:167
__aperture_remove_legacy_vga_devices drivers/video/aperture.c:331 [inline]
aperture_remove_conflicting_pci_devices+0x16a/0x1e0 drivers/video/aperture.c:369
virtio_gpu_pci_quirk drivers/gpu/drm/virtio/virtgpu_drv.c:61 [inline]
virtio_gpu_probe+0x408/0x4e0 drivers/gpu/drm/virtio/virtgpu_drv.c:92
virtio_dev_probe+0x586/0x8a0 drivers/virtio/virtio.c:341
call_driver_probe drivers/base/dd.c:578 [inline]
really_probe+0x23e/0xa90 drivers/base/dd.c:657
__driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
__driver_attach+0x283/0x580 drivers/base/dd.c:1215
bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368
bus_add_driver+0x2e9/0x690 drivers/base/bus.c:673
driver_register+0x15c/0x4b0 drivers/base/driver.c:246
do_one_initcall+0x128/0x700 init/main.c:1269
do_initcall_level init/main.c:1331 [inline]
do_initcalls init/main.c:1347 [inline]
do_basic_setup init/main.c:1366 [inline]
kernel_init_freeable+0x69d/0xca0 init/main.c:1580
kernel_init+0x1c/0x2b0 init/main.c:1469
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 ((console_sem).lock){-...}-{2:2}:
check_prev_add kernel/locking/lockdep.c:3158 [inline]
check_prevs_add kernel/locking/lockdep.c:3277 [inline]
validate_chain kernel/locking/lockdep.c:3901 [inline]
__lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5199
lock_acquire kernel/locking/lockdep.c:5822 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
__down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
console_trylock kernel/printk/printk.c:2827 [inline]
console_trylock_spinning kernel/printk/printk.c:1990 [inline]
vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2406
vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
_printk+0xc8/0x100 kernel/printk/printk.c:2432
fail_dump lib/fault-inject.c:45 [inline]
should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
bpf_prog_d0e9ac47b081aec3+0x48/0x4a
bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
__bpf_prog_run include/linux/filter.h:691 [inline]
bpf_prog_run include/linux/filter.h:698 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
__bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
trace_timer_start include/trace/events/timer.h:52 [inline]
enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
internal_add_timer kernel/time/timer.c:688 [inline]
__mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
__queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
queue_delayed_work include/linux/workqueue.h:636 [inline]
fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
process_output_block drivers/tty/n_tty.c:574 [inline]
n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
new_sync_write fs/read_write.c:590 [inline]
vfs_write+0x6b5/0x1140 fs/read_write.c:683
ksys_write+0x12f/0x260 fs/read_write.c:736
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Chain exists of:
(console_sem).lock --> &rq->__lock --> &base->lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&base->lock);
lock(&rq->__lock);
lock(&base->lock);
lock((console_sem).lock);
*** DEADLOCK ***
7 locks held by syz-executor291/5332:
#0: ffff8880353610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock drivers/tty/tty_io.c:954 [inline]
#1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: iterate_tty_write drivers/tty/tty_io.c:973 [inline]
#1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: file_tty_write.constprop.0+0x281/0x9a0 drivers/tty/tty_io.c:1096
#2: ffff8880353612e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_write+0x1bd/0x1140 drivers/tty/n_tty.c:2372
#3: ffffc9000324e380 (&ldata->output_lock){+.+.}-{3:3}, at: process_output_block drivers/tty/n_tty.c:529 [inline]
#3: ffffc9000324e380 (&ldata->output_lock){+.+.}-{3:3}, at: n_tty_write+0x533/0x1140 drivers/tty/n_tty.c:2389
#4: ffffffff8dda8460 (console_lock){+.+.}-{0:0}, at: do_con_write+0x154/0x7bb0 drivers/tty/vt/vt.c:3056
#5: ffff88806a92a858 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6c1/0xdc0 kernel/time/timer.c:1164
#6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
#6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
#6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2447
stack backtrace:
CPU: 3 UID: 0 PID: 5332 Comm: syz-executor291 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2203
check_prev_add kernel/locking/lockdep.c:3158 [inline]
check_prevs_add kernel/locking/lockdep.c:3277 [inline]
validate_chain kernel/locking/lockdep.c:3901 [inline]
__lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5199
lock_acquire kernel/locking/lockdep.c:5822 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
__down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
console_trylock kernel/printk/printk.c:2827 [inline]
console_trylock_spinning kernel/printk/printk.c:1990 [inline]
vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2406
vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
_printk+0xc8/0x100 kernel/printk/printk.c:2432
fail_dump lib/fault-inject.c:45 [inline]
should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
bpf_prog_d0e9ac47b081aec3+0x48/0x4a
bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
__bpf_prog_run include/linux/filter.h:691 [inline]
bpf_prog_run include/linux/filter.h:698 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
__bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
trace_timer_start include/trace/events/timer.h:52 [inline]
enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
internal_add_timer kernel/time/timer.c:688 [inline]
__mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
__queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
queue_delayed_work include/linux/workqueue.h:636 [inline]
fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
process_output_block drivers/tty/n_tty.c:574 [inline]
n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
new_sync_write fs/read_write.c:590 [inline]
vfs_write+0x6b5/0x1140 fs/read_write.c:683
ksys_write+0x12f/0x260 fs/read_write.c:736
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36b5809869
Code: 48 83 c4 28 c3 e8 17 1a 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeb8b42888 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ffeb8b42890 RCX: 00007f36b5809869
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000006
RBP: 0000000000000001 R08: 00007ffeb8b42627 R09: 00007f36b5870033
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeb8b42a68 R14: 0000000000000001 R15: 0000000000000001
</TASK>
CPU: 3 UID: 0 PID: 5332 Comm: syz-executor291 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:93 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
fail_dump lib/fault-inject.c:52 [inline]
should_fail_ex+0x497/0x5b0 lib/fault-inject.c:153
strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
bpf_prog_d0e9ac47b081aec3+0x48/0x4a
bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
__bpf_prog_run include/linux/filter.h:691 [inline]
bpf_prog_run include/linux/filter.h:698 [inline]
__bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
__bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
trace_timer_start include/trace/events/timer.h:52 [inline]
enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
internal_add_timer kernel/time/timer.c:688 [inline]
__mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
__queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
queue_delayed_work include/linux/workqueue.h:636 [inline]
fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
process_output_block drivers/tty/n_tty.c:574 [inline]
n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
new_sync_write fs/read_write.c:590 [inline]
vfs_write+0x6b5/0x1140 fs/read_write.c:683
ksys_write+0x12f/0x260 fs/read_write.c:736
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f36b5809869
Code: 48 83 c4 28 c3 e8 17 1a 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeb8b42888 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ffeb8b42890 RCX: 00007f36b5809869
RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000006
RBP: 0000000000000001 R08: 00007ffeb8b42627 R09: 00007f36b5870033
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeb8b42a68 R14: 0000000000000001 R15: 0000000000000001
</TASK>
---
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#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [syzbot] [trace?] [bpf?] possible deadlock in __mod_timer (4)
2024-09-22 6:39 [syzbot] [trace?] [bpf?] possible deadlock in __mod_timer (4) syzbot
@ 2024-09-26 4:53 ` Steven Rostedt
2024-09-26 13:06 ` Petr Mladek
0 siblings, 1 reply; 3+ messages in thread
From: Steven Rostedt @ 2024-09-26 4:53 UTC (permalink / raw)
To: syzbot
Cc: andrii, ast, bpf, daniel, eddyz87, haoluo, john.fastabend, jolsa,
kpsingh, linux-kernel, linux-trace-kernel, martin.lau,
mathieu.desnoyers, mattbobrowski, mhiramat, sdf, song,
syzkaller-bugs, yonghong.song, John Ogness, Petr Mladek
On Sat, 21 Sep 2024 23:39:17 -0700
syzbot <syzbot+83a876aef81c9a485ae8@syzkaller.appspotmail.com> wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: a940d9a43e62 Merge tag 'soc-arm-6.12' of git://git.kernel...
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=12d1c69f980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=44d46e514184cd24
> dashboard link: https://syzkaller.appspot.com/bug?extid=83a876aef81c9a485ae8
> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11597677980000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13cd7500580000
>
> Downloadable assets:
> disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-a940d9a4.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/e9929bfe422c/vmlinux-a940d9a4.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/a6c74ee261ed/bzImage-a940d9a4.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+83a876aef81c9a485ae8@syzkaller.appspotmail.com
>
> FAULT_INJECTION: forcing a failure.
> name fail_usercopy, interval 1, probability 0, space 0, times 1
> ======================================================
> WARNING: possible circular locking dependency detected
> 6.11.0-syzkaller-03917-ga940d9a43e62 #0 Not tainted
> ------------------------------------------------------
> syz-executor291/5332 is trying to acquire lock:
> ffffffff8dda88d8 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
I'm assuming that lockdep splats like this will no longer be an issue come 6.12?
-- Steve
>
> but task is already holding lock:
> ffff88806a92a858 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6c1/0xdc0 kernel/time/timer.c:1164
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #3 (&base->lock){-.-.}-{2:2}:
> __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> lock_timer_base+0x5d/0x220 kernel/time/timer.c:1051
> __mod_timer+0x426/0xdc0 kernel/time/timer.c:1132
> add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> psi_task_change+0x1b4/0x2e0 kernel/sched/psi.c:913
> psi_enqueue kernel/sched/stats.h:143 [inline]
> enqueue_task+0x1a5/0x350 kernel/sched/core.c:1975
> activate_task kernel/sched/core.c:2009 [inline]
> wake_up_new_task+0x5ba/0xd30 kernel/sched/core.c:4689
> kernel_clone+0x236/0x960 kernel/fork.c:2812
> user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
> rest_init+0x23/0x2b0 init/main.c:712
> start_kernel+0x3e4/0x4d0 init/main.c:1105
> x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
> x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
> common_startup_64+0x13e/0x148
>
> -> #2 (&rq->__lock){-.-.}-{2:2}:
> _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
> raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:560
> raw_spin_rq_lock kernel/sched/sched.h:1415 [inline]
> rq_lock kernel/sched/sched.h:1714 [inline]
> task_fork_fair+0x73/0x250 kernel/sched/fair.c:12710
> sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4633
> copy_process+0x439b/0x8dd0 kernel/fork.c:2483
> kernel_clone+0xfd/0x960 kernel/fork.c:2781
> user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
> rest_init+0x23/0x2b0 init/main.c:712
> start_kernel+0x3e4/0x4d0 init/main.c:1105
> x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
> x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
> common_startup_64+0x13e/0x148
>
> -> #1 (&p->pi_lock){-.-.}-{2:2}:
> __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]
> try_to_wake_up+0x9a/0x13e0 kernel/sched/core.c:4051
> up+0x79/0xb0 kernel/locking/semaphore.c:191
> __up_console_sem+0x85/0xe0 kernel/printk/printk.c:343
> __console_unlock kernel/printk/printk.c:2844 [inline]
> __console_flush_and_unlock kernel/printk/printk.c:3241 [inline]
> console_unlock+0x1dc/0x210 kernel/printk/printk.c:3279
> vga_remove_vgacon drivers/pci/vgaarb.c:186 [inline]
> vga_remove_vgacon+0x90/0xd0 drivers/pci/vgaarb.c:167
> __aperture_remove_legacy_vga_devices drivers/video/aperture.c:331 [inline]
> aperture_remove_conflicting_pci_devices+0x16a/0x1e0 drivers/video/aperture.c:369
> virtio_gpu_pci_quirk drivers/gpu/drm/virtio/virtgpu_drv.c:61 [inline]
> virtio_gpu_probe+0x408/0x4e0 drivers/gpu/drm/virtio/virtgpu_drv.c:92
> virtio_dev_probe+0x586/0x8a0 drivers/virtio/virtio.c:341
> call_driver_probe drivers/base/dd.c:578 [inline]
> really_probe+0x23e/0xa90 drivers/base/dd.c:657
> __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
> driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
> __driver_attach+0x283/0x580 drivers/base/dd.c:1215
> bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368
> bus_add_driver+0x2e9/0x690 drivers/base/bus.c:673
> driver_register+0x15c/0x4b0 drivers/base/driver.c:246
> do_one_initcall+0x128/0x700 init/main.c:1269
> do_initcall_level init/main.c:1331 [inline]
> do_initcalls init/main.c:1347 [inline]
> do_basic_setup init/main.c:1366 [inline]
> kernel_init_freeable+0x69d/0xca0 init/main.c:1580
> kernel_init+0x1c/0x2b0 init/main.c:1469
> ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> -> #0 ((console_sem).lock){-...}-{2:2}:
> check_prev_add kernel/locking/lockdep.c:3158 [inline]
> check_prevs_add kernel/locking/lockdep.c:3277 [inline]
> validate_chain kernel/locking/lockdep.c:3901 [inline]
> __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5199
> lock_acquire kernel/locking/lockdep.c:5822 [inline]
> lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787
> __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
> __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
> console_trylock kernel/printk/printk.c:2827 [inline]
> console_trylock_spinning kernel/printk/printk.c:1990 [inline]
> vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2406
> vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
> _printk+0xc8/0x100 kernel/printk/printk.c:2432
> fail_dump lib/fault-inject.c:45 [inline]
> should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
> strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
> strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
> bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
> ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
> bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
> bpf_prog_d0e9ac47b081aec3+0x48/0x4a
> bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
> __bpf_prog_run include/linux/filter.h:691 [inline]
> bpf_prog_run include/linux/filter.h:698 [inline]
> __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
> bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
> __bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
> trace_timer_start include/trace/events/timer.h:52 [inline]
> enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
> internal_add_timer kernel/time/timer.c:688 [inline]
> __mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
> add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> queue_delayed_work include/linux/workqueue.h:636 [inline]
> fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
> fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
> hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
> do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
> con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
> process_output_block drivers/tty/n_tty.c:574 [inline]
> n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
> iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
> file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
> new_sync_write fs/read_write.c:590 [inline]
> vfs_write+0x6b5/0x1140 fs/read_write.c:683
> ksys_write+0x12f/0x260 fs/read_write.c:736
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> other info that might help us debug this:
>
> Chain exists of:
> (console_sem).lock --> &rq->__lock --> &base->lock
>
> Possible unsafe locking scenario:
>
> CPU0 CPU1
> ---- ----
> lock(&base->lock);
> lock(&rq->__lock);
> lock(&base->lock);
> lock((console_sem).lock);
>
> *** DEADLOCK ***
>
> 7 locks held by syz-executor291/5332:
> #0: ffff8880353610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
> #1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock drivers/tty/tty_io.c:954 [inline]
> #1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: iterate_tty_write drivers/tty/tty_io.c:973 [inline]
> #1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: file_tty_write.constprop.0+0x281/0x9a0 drivers/tty/tty_io.c:1096
> #2: ffff8880353612e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_write+0x1bd/0x1140 drivers/tty/n_tty.c:2372
> #3: ffffc9000324e380 (&ldata->output_lock){+.+.}-{3:3}, at: process_output_block drivers/tty/n_tty.c:529 [inline]
> #3: ffffc9000324e380 (&ldata->output_lock){+.+.}-{3:3}, at: n_tty_write+0x533/0x1140 drivers/tty/n_tty.c:2389
> #4: ffffffff8dda8460 (console_lock){+.+.}-{0:0}, at: do_con_write+0x154/0x7bb0 drivers/tty/vt/vt.c:3056
> #5: ffff88806a92a858 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6c1/0xdc0 kernel/time/timer.c:1164
> #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
> #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
> #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
> #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2447
>
> stack backtrace:
> CPU: 3 UID: 0 PID: 5332 Comm: syz-executor291 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
> Call Trace:
> <TASK>
> __dump_stack lib/dump_stack.c:93 [inline]
> dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
> print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
> check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2203
> check_prev_add kernel/locking/lockdep.c:3158 [inline]
> check_prevs_add kernel/locking/lockdep.c:3277 [inline]
> validate_chain kernel/locking/lockdep.c:3901 [inline]
> __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5199
> lock_acquire kernel/locking/lockdep.c:5822 [inline]
> lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787
> __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
> __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
> console_trylock kernel/printk/printk.c:2827 [inline]
> console_trylock_spinning kernel/printk/printk.c:1990 [inline]
> vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2406
> vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
> _printk+0xc8/0x100 kernel/printk/printk.c:2432
> fail_dump lib/fault-inject.c:45 [inline]
> should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
> strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
> strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
> bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
> ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
> bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
> bpf_prog_d0e9ac47b081aec3+0x48/0x4a
> bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
> __bpf_prog_run include/linux/filter.h:691 [inline]
> bpf_prog_run include/linux/filter.h:698 [inline]
> __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
> bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
> __bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
> trace_timer_start include/trace/events/timer.h:52 [inline]
> enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
> internal_add_timer kernel/time/timer.c:688 [inline]
> __mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
> add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> queue_delayed_work include/linux/workqueue.h:636 [inline]
> fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
> fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
> hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
> do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
> con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
> process_output_block drivers/tty/n_tty.c:574 [inline]
> n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
> iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
> file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
> new_sync_write fs/read_write.c:590 [inline]
> vfs_write+0x6b5/0x1140 fs/read_write.c:683
> ksys_write+0x12f/0x260 fs/read_write.c:736
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f36b5809869
> Code: 48 83 c4 28 c3 e8 17 1a 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007ffeb8b42888 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> RAX: ffffffffffffffda RBX: 00007ffeb8b42890 RCX: 00007f36b5809869
> RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000006
> RBP: 0000000000000001 R08: 00007ffeb8b42627 R09: 00007f36b5870033
> R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007ffeb8b42a68 R14: 0000000000000001 R15: 0000000000000001
> </TASK>
> CPU: 3 UID: 0 PID: 5332 Comm: syz-executor291 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
> Call Trace:
> <TASK>
> __dump_stack lib/dump_stack.c:93 [inline]
> dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
> fail_dump lib/fault-inject.c:52 [inline]
> should_fail_ex+0x497/0x5b0 lib/fault-inject.c:153
> strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
> strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
> bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
> ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
> bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
> bpf_prog_d0e9ac47b081aec3+0x48/0x4a
> bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
> __bpf_prog_run include/linux/filter.h:691 [inline]
> bpf_prog_run include/linux/filter.h:698 [inline]
> __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
> bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
> __bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
> trace_timer_start include/trace/events/timer.h:52 [inline]
> enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
> internal_add_timer kernel/time/timer.c:688 [inline]
> __mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
> add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> queue_delayed_work include/linux/workqueue.h:636 [inline]
> fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
> fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
> hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
> do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
> con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
> process_output_block drivers/tty/n_tty.c:574 [inline]
> n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
> iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
> file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
> new_sync_write fs/read_write.c:590 [inline]
> vfs_write+0x6b5/0x1140 fs/read_write.c:683
> ksys_write+0x12f/0x260 fs/read_write.c:736
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f36b5809869
> Code: 48 83 c4 28 c3 e8 17 1a 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007ffeb8b42888 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> RAX: ffffffffffffffda RBX: 00007ffeb8b42890 RCX: 00007f36b5809869
> RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000006
> RBP: 0000000000000001 R08: 00007ffeb8b42627 R09: 00007f36b5870033
> R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007ffeb8b42a68 R14: 0000000000000001 R15: 0000000000000001
> </TASK>
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
>
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [syzbot] [trace?] [bpf?] possible deadlock in __mod_timer (4)
2024-09-26 4:53 ` Steven Rostedt
@ 2024-09-26 13:06 ` Petr Mladek
0 siblings, 0 replies; 3+ messages in thread
From: Petr Mladek @ 2024-09-26 13:06 UTC (permalink / raw)
To: Steven Rostedt
Cc: syzbot, andrii, ast, bpf, daniel, eddyz87, haoluo, john.fastabend,
jolsa, kpsingh, linux-kernel, linux-trace-kernel, martin.lau,
mathieu.desnoyers, mattbobrowski, mhiramat, sdf, song,
syzkaller-bugs, yonghong.song, John Ogness
On Thu 2024-09-26 00:53:21, Steven Rostedt wrote:
> On Sat, 21 Sep 2024 23:39:17 -0700
> syzbot <syzbot+83a876aef81c9a485ae8@syzkaller.appspotmail.com> wrote:
>
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit: a940d9a43e62 Merge tag 'soc-arm-6.12' of git://git.kernel...
> > git tree: upstream
> > console output: https://syzkaller.appspot.com/x/log.txt?x=12d1c69f980000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=44d46e514184cd24
> > dashboard link: https://syzkaller.appspot.com/bug?extid=83a876aef81c9a485ae8
> > compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11597677980000
> > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13cd7500580000
> >
> > Downloadable assets:
> > disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-a940d9a4.raw.xz
> > vmlinux: https://storage.googleapis.com/syzbot-assets/e9929bfe422c/vmlinux-a940d9a4.xz
> > kernel image: https://storage.googleapis.com/syzbot-assets/a6c74ee261ed/bzImage-a940d9a4.xz
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+83a876aef81c9a485ae8@syzkaller.appspotmail.com
> >
> > FAULT_INJECTION: forcing a failure.
> > name fail_usercopy, interval 1, probability 0, space 0, times 1
> > ======================================================
> > WARNING: possible circular locking dependency detected
> > 6.11.0-syzkaller-03917-ga940d9a43e62 #0 Not tainted
> > ------------------------------------------------------
> > syz-executor291/5332 is trying to acquire lock:
> > ffffffff8dda88d8 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
>
> I'm assuming that lockdep splats like this will no longer be an issue come 6.12?
I am afraid that it still would happen in 6.12. :-(
The legacy loop (console_trylock()/unlock()) will still be called
there when there is a boot or a legacy console registered.
I actually guess that all console will be legacy in 6.12 because
the conversion of the uart 8250 console driver still need some love,
see the last version at
https://lore.kernel.org/r/20240913140538.221708-1-john.ogness@linutronix.de
The only exception will be CONFIG_RT mode which would offload even
the legacy loop to a dedicated kthread.
Best Regards,
Petr
> >
> > but task is already holding lock:
> > ffff88806a92a858 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6c1/0xdc0 kernel/time/timer.c:1164
> >
> > which lock already depends on the new lock.
> >
> >
> > the existing dependency chain (in reverse order) is:
> >
> > -> #3 (&base->lock){-.-.}-{2:2}:
> > __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> > _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> > lock_timer_base+0x5d/0x220 kernel/time/timer.c:1051
> > __mod_timer+0x426/0xdc0 kernel/time/timer.c:1132
> > add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> > __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> > queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> > psi_task_change+0x1b4/0x2e0 kernel/sched/psi.c:913
> > psi_enqueue kernel/sched/stats.h:143 [inline]
> > enqueue_task+0x1a5/0x350 kernel/sched/core.c:1975
> > activate_task kernel/sched/core.c:2009 [inline]
> > wake_up_new_task+0x5ba/0xd30 kernel/sched/core.c:4689
> > kernel_clone+0x236/0x960 kernel/fork.c:2812
> > user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
> > rest_init+0x23/0x2b0 init/main.c:712
> > start_kernel+0x3e4/0x4d0 init/main.c:1105
> > x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
> > x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
> > common_startup_64+0x13e/0x148
> >
> > -> #2 (&rq->__lock){-.-.}-{2:2}:
> > _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378
> > raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:560
> > raw_spin_rq_lock kernel/sched/sched.h:1415 [inline]
> > rq_lock kernel/sched/sched.h:1714 [inline]
> > task_fork_fair+0x73/0x250 kernel/sched/fair.c:12710
> > sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4633
> > copy_process+0x439b/0x8dd0 kernel/fork.c:2483
> > kernel_clone+0xfd/0x960 kernel/fork.c:2781
> > user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
> > rest_init+0x23/0x2b0 init/main.c:712
> > start_kernel+0x3e4/0x4d0 init/main.c:1105
> > x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
> > x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
> > common_startup_64+0x13e/0x148
> >
> > -> #1 (&p->pi_lock){-.-.}-{2:2}:
> > __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> > _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> > class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline]
> > try_to_wake_up+0x9a/0x13e0 kernel/sched/core.c:4051
> > up+0x79/0xb0 kernel/locking/semaphore.c:191
> > __up_console_sem+0x85/0xe0 kernel/printk/printk.c:343
> > __console_unlock kernel/printk/printk.c:2844 [inline]
> > __console_flush_and_unlock kernel/printk/printk.c:3241 [inline]
> > console_unlock+0x1dc/0x210 kernel/printk/printk.c:3279
> > vga_remove_vgacon drivers/pci/vgaarb.c:186 [inline]
> > vga_remove_vgacon+0x90/0xd0 drivers/pci/vgaarb.c:167
> > __aperture_remove_legacy_vga_devices drivers/video/aperture.c:331 [inline]
> > aperture_remove_conflicting_pci_devices+0x16a/0x1e0 drivers/video/aperture.c:369
> > virtio_gpu_pci_quirk drivers/gpu/drm/virtio/virtgpu_drv.c:61 [inline]
> > virtio_gpu_probe+0x408/0x4e0 drivers/gpu/drm/virtio/virtgpu_drv.c:92
> > virtio_dev_probe+0x586/0x8a0 drivers/virtio/virtio.c:341
> > call_driver_probe drivers/base/dd.c:578 [inline]
> > really_probe+0x23e/0xa90 drivers/base/dd.c:657
> > __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
> > driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
> > __driver_attach+0x283/0x580 drivers/base/dd.c:1215
> > bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368
> > bus_add_driver+0x2e9/0x690 drivers/base/bus.c:673
> > driver_register+0x15c/0x4b0 drivers/base/driver.c:246
> > do_one_initcall+0x128/0x700 init/main.c:1269
> > do_initcall_level init/main.c:1331 [inline]
> > do_initcalls init/main.c:1347 [inline]
> > do_basic_setup init/main.c:1366 [inline]
> > kernel_init_freeable+0x69d/0xca0 init/main.c:1580
> > kernel_init+0x1c/0x2b0 init/main.c:1469
> > ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
> > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> >
> > -> #0 ((console_sem).lock){-...}-{2:2}:
> > check_prev_add kernel/locking/lockdep.c:3158 [inline]
> > check_prevs_add kernel/locking/lockdep.c:3277 [inline]
> > validate_chain kernel/locking/lockdep.c:3901 [inline]
> > __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5199
> > lock_acquire kernel/locking/lockdep.c:5822 [inline]
> > lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787
> > __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> > _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> > down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
> > __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
> > console_trylock kernel/printk/printk.c:2827 [inline]
> > console_trylock_spinning kernel/printk/printk.c:1990 [inline]
> > vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2406
> > vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
> > _printk+0xc8/0x100 kernel/printk/printk.c:2432
> > fail_dump lib/fault-inject.c:45 [inline]
> > should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
> > strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
> > strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
> > bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
> > ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
> > bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
> > bpf_prog_d0e9ac47b081aec3+0x48/0x4a
> > bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
> > __bpf_prog_run include/linux/filter.h:691 [inline]
> > bpf_prog_run include/linux/filter.h:698 [inline]
> > __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
> > bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
> > __bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
> > trace_timer_start include/trace/events/timer.h:52 [inline]
> > enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
> > internal_add_timer kernel/time/timer.c:688 [inline]
> > __mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
> > add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> > __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> > queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> > queue_delayed_work include/linux/workqueue.h:636 [inline]
> > fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
> > fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
> > hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
> > do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
> > con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
> > process_output_block drivers/tty/n_tty.c:574 [inline]
> > n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
> > iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
> > file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
> > new_sync_write fs/read_write.c:590 [inline]
> > vfs_write+0x6b5/0x1140 fs/read_write.c:683
> > ksys_write+0x12f/0x260 fs/read_write.c:736
> > do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> > do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
> > entry_SYSCALL_64_after_hwframe+0x77/0x7f
> >
> > other info that might help us debug this:
> >
> > Chain exists of:
> > (console_sem).lock --> &rq->__lock --> &base->lock
> >
> > Possible unsafe locking scenario:
> >
> > CPU0 CPU1
> > ---- ----
> > lock(&base->lock);
> > lock(&rq->__lock);
> > lock(&base->lock);
> > lock((console_sem).lock);
> >
> > *** DEADLOCK ***
> >
> > 7 locks held by syz-executor291/5332:
> > #0: ffff8880353610a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
> > #1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock drivers/tty/tty_io.c:954 [inline]
> > #1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: iterate_tty_write drivers/tty/tty_io.c:973 [inline]
> > #1: ffff888035361130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: file_tty_write.constprop.0+0x281/0x9a0 drivers/tty/tty_io.c:1096
> > #2: ffff8880353612e8 (&tty->termios_rwsem){++++}-{3:3}, at: n_tty_write+0x1bd/0x1140 drivers/tty/n_tty.c:2372
> > #3: ffffc9000324e380 (&ldata->output_lock){+.+.}-{3:3}, at: process_output_block drivers/tty/n_tty.c:529 [inline]
> > #3: ffffc9000324e380 (&ldata->output_lock){+.+.}-{3:3}, at: n_tty_write+0x533/0x1140 drivers/tty/n_tty.c:2389
> > #4: ffffffff8dda8460 (console_lock){+.+.}-{0:0}, at: do_con_write+0x154/0x7bb0 drivers/tty/vt/vt.c:3056
> > #5: ffff88806a92a858 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x6c1/0xdc0 kernel/time/timer.c:1164
> > #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
> > #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
> > #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
> > #6: ffffffff8ddbaea0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1c2/0x590 kernel/trace/bpf_trace.c:2447
> >
> > stack backtrace:
> > CPU: 3 UID: 0 PID: 5332 Comm: syz-executor291 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
> > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
> > Call Trace:
> > <TASK>
> > __dump_stack lib/dump_stack.c:93 [inline]
> > dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
> > print_circular_bug+0x419/0x5d0 kernel/locking/lockdep.c:2074
> > check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2203
> > check_prev_add kernel/locking/lockdep.c:3158 [inline]
> > check_prevs_add kernel/locking/lockdep.c:3277 [inline]
> > validate_chain kernel/locking/lockdep.c:3901 [inline]
> > __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5199
> > lock_acquire kernel/locking/lockdep.c:5822 [inline]
> > lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5787
> > __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
> > _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
> > down_trylock+0x12/0x70 kernel/locking/semaphore.c:139
> > __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:326
> > console_trylock kernel/printk/printk.c:2827 [inline]
> > console_trylock_spinning kernel/printk/printk.c:1990 [inline]
> > vprintk_emit+0x3ec/0x6f0 kernel/printk/printk.c:2406
> > vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:68
> > _printk+0xc8/0x100 kernel/printk/printk.c:2432
> > fail_dump lib/fault-inject.c:45 [inline]
> > should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
> > strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
> > strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
> > bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
> > ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
> > bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
> > bpf_prog_d0e9ac47b081aec3+0x48/0x4a
> > bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
> > __bpf_prog_run include/linux/filter.h:691 [inline]
> > bpf_prog_run include/linux/filter.h:698 [inline]
> > __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
> > bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
> > __bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
> > trace_timer_start include/trace/events/timer.h:52 [inline]
> > enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
> > internal_add_timer kernel/time/timer.c:688 [inline]
> > __mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
> > add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> > __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> > queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> > queue_delayed_work include/linux/workqueue.h:636 [inline]
> > fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
> > fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
> > hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
> > do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
> > con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
> > process_output_block drivers/tty/n_tty.c:574 [inline]
> > n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
> > iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
> > file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
> > new_sync_write fs/read_write.c:590 [inline]
> > vfs_write+0x6b5/0x1140 fs/read_write.c:683
> > ksys_write+0x12f/0x260 fs/read_write.c:736
> > do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> > do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
> > entry_SYSCALL_64_after_hwframe+0x77/0x7f
> > RIP: 0033:0x7f36b5809869
> > Code: 48 83 c4 28 c3 e8 17 1a 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
> > RSP: 002b:00007ffeb8b42888 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> > RAX: ffffffffffffffda RBX: 00007ffeb8b42890 RCX: 00007f36b5809869
> > RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000006
> > RBP: 0000000000000001 R08: 00007ffeb8b42627 R09: 00007f36b5870033
> > R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
> > R13: 00007ffeb8b42a68 R14: 0000000000000001 R15: 0000000000000001
> > </TASK>
> > CPU: 3 UID: 0 PID: 5332 Comm: syz-executor291 Not tainted 6.11.0-syzkaller-03917-ga940d9a43e62 #0
> > Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
> > Call Trace:
> > <TASK>
> > __dump_stack lib/dump_stack.c:93 [inline]
> > dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
> > fail_dump lib/fault-inject.c:52 [inline]
> > should_fail_ex+0x497/0x5b0 lib/fault-inject.c:153
> > strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
> > strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
> > bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
> > ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
> > bpf_probe_read_compat_str+0xf1/0x170 kernel/trace/bpf_trace.c:307
> > bpf_prog_d0e9ac47b081aec3+0x48/0x4a
> > bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
> > __bpf_prog_run include/linux/filter.h:691 [inline]
> > bpf_prog_run include/linux/filter.h:698 [inline]
> > __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
> > bpf_trace_run2+0x231/0x590 kernel/trace/bpf_trace.c:2447
> > __bpf_trace_timer_start+0xc7/0x100 include/trace/events/timer.h:52
> > trace_timer_start include/trace/events/timer.h:52 [inline]
> > enqueue_timer+0x2b4/0x550 kernel/time/timer.c:663
> > internal_add_timer kernel/time/timer.c:688 [inline]
> > __mod_timer+0x8d7/0xdc0 kernel/time/timer.c:1183
> > add_timer_global+0x8a/0xc0 kernel/time/timer.c:1330
> > __queue_delayed_work+0x1ba/0x2e0 kernel/workqueue.c:2525
> > queue_delayed_work_on+0x12a/0x150 kernel/workqueue.c:2554
> > queue_delayed_work include/linux/workqueue.h:636 [inline]
> > fbcon_add_cursor_work drivers/video/fbdev/core/fbcon.c:392 [inline]
> > fbcon_cursor+0x4a0/0x520 drivers/video/fbdev/core/fbcon.c:1316
> > hide_cursor+0x84/0x220 drivers/tty/vt/vt.c:846
> > do_con_write+0x21e6/0x7bb0 drivers/tty/vt/vt.c:3068
> > con_write+0x23/0xb0 drivers/tty/vt/vt.c:3434
> > process_output_block drivers/tty/n_tty.c:574 [inline]
> > n_tty_write+0x419/0x1140 drivers/tty/n_tty.c:2389
> > iterate_tty_write drivers/tty/tty_io.c:1021 [inline]
> > file_tty_write.constprop.0+0x506/0x9a0 drivers/tty/tty_io.c:1096
> > new_sync_write fs/read_write.c:590 [inline]
> > vfs_write+0x6b5/0x1140 fs/read_write.c:683
> > ksys_write+0x12f/0x260 fs/read_write.c:736
> > do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> > do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
> > entry_SYSCALL_64_after_hwframe+0x77/0x7f
> > RIP: 0033:0x7f36b5809869
> > Code: 48 83 c4 28 c3 e8 17 1a 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
> > RSP: 002b:00007ffeb8b42888 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
> > RAX: ffffffffffffffda RBX: 00007ffeb8b42890 RCX: 00007f36b5809869
> > RDX: 0000000000001006 RSI: 0000000020001040 RDI: 0000000000000006
> > RBP: 0000000000000001 R08: 00007ffeb8b42627 R09: 00007f36b5870033
> > R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
> > R13: 00007ffeb8b42a68 R14: 0000000000000001 R15: 0000000000000001
> > </TASK>
> >
> >
> > ---
> > This report is generated by a bot. It may contain errors.
> > See https://goo.gl/tpsmEJ for more information about syzbot.
> > syzbot engineers can be reached at syzkaller@googlegroups.com.
> >
> > syzbot will keep track of this issue. See:
> > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> >
> > If the report is already addressed, let syzbot know by replying with:
> > #syz fix: exact-commit-title
> >
> > If you want syzbot to run the reproducer, reply with:
> > #syz test: git://repo/address.git branch-or-commit-hash
> > If you attach or paste a git patch, syzbot will apply it before testing.
> >
> > If you want to overwrite report's subsystems, reply with:
> > #syz set subsystems: new-subsystem
> > (See the list of subsystem names on the web dashboard)
> >
> > If the report is a duplicate of another one, reply with:
> > #syz dup: exact-subject-of-another-report
> >
> > If you want to undo deduplication, reply with:
> > #syz undup
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2024-09-26 13:06 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-09-22 6:39 [syzbot] [trace?] [bpf?] possible deadlock in __mod_timer (4) syzbot
2024-09-26 4:53 ` Steven Rostedt
2024-09-26 13:06 ` Petr Mladek
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