From: syzbot <syzbot+0d22039ef0915696ad4b@syzkaller.appspotmail.com>
To: linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org,
syzkaller-bugs@googlegroups.com, ulf.hansson@linaro.org,
ulfh@kernel.org
Subject: [syzbot] [mmc?] WARNING: suspicious RCU usage in mmc_free_host
Date: Fri, 21 Aug 2026 23:04:39 -0700 [thread overview]
Message-ID: <6a893bf7.dbb3a75c.13dd47.002d.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 818bebeb63dd drm/xe: Don't hand out the flat CCS storage a..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1109e549580000
kernel config: https://syzkaller.appspot.com/x/.config?x=59b38fbc070dad5e
dashboard link: https://syzkaller.appspot.com/bug?extid=0d22039ef0915696ad4b
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/51af0608b198/disk-818bebeb.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ecaa10d3a300/vmlinux-818bebeb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6ce61fdcbede/bzImage-818bebeb.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0d22039ef0915696ad4b@syzkaller.appspotmail.com
=============================
WARNING: suspicious RCU usage
syzkaller #0 Tainted: G L
-----------------------------
kernel/sched/core.c:9196 Illegal context switch in RCU-sched read-side critical section!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
locks held by syz-executor/5632: 9, last CPU#1:
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1548 [inline]
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1601
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0 mm/mmap.c:1716
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0 mm/mmap.c:1723
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:347 [inline]
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pte_range mm/memory.c:1292 [inline]
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pmd_range+0x70f/0x5c50 mm/memory.c:1428
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid+0xba/0x490 include/linux/mmzone.h:2266
#8: ffffc90000a08cc0 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x5f0 kernel/time/timer.c:1745
stack backtrace:
CPU: 1 UID: 0 PID: 5632 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6894
__might_resched+0xbb/0x4c0 kernel/sched/core.c:9196
__cancel_work_sync+0x6d/0x110 kernel/workqueue.c:4552
mmc_free_host+0x19/0x30 drivers/mmc/core/host.c:700
call_timer_fn+0x18d/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767
irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x222/0x350 kernel/locking/lockdep.c:5890
Code: ff ff ff e8 a0 20 39 0a f7 44 24 08 00 02 00 00 0f 84 39 ff ff ff 65 48 8b 05 f2 0b ce 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 cf 27 3c 0a cc 48 8d 3d a7 64 b9
RSP: 0018:ffffc90004307210 EFLAGS: 00000282
RAX: 2ab30850d67e6b00 RBX: 0000000000000000 RCX: 8000000000000003
RDX: 00000000dc7298f8 RSI: ffffffff8e4e132a RDI: ffffffff8c4cf580
RBP: ffffffff8242ba4a R08: ffffffff8242ba4a R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb5a420 R12: 0000000000000002
R13: ffffffff8eb5a420 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
pfn_valid+0xd6/0x490 include/linux/mmzone.h:2266
page_table_check_set+0x25/0x530 mm/page_table_check.c:105
page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
set_ptes include/linux/pgtable.h:447 [inline]
__copy_present_ptes mm/memory.c:1138 [inline]
copy_present_ptes mm/memory.c:1217 [inline]
copy_pte_range mm/memory.c:1340 [inline]
copy_pmd_range+0x4b46/0x5c50 mm/memory.c:1428
copy_pud_range mm/memory.c:1465 [inline]
copy_p4d_range mm/memory.c:1489 [inline]
copy_page_range+0xc25/0x1230 mm/memory.c:1575
dup_mmap+0xf17/0x1dc0 mm/mmap.c:1819
dup_mm kernel/fork.c:1549 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1601
copy_process+0x1e75/0x43e0 kernel/fork.c:2313
kernel_clone+0x2d7/0x940 kernel/fork.c:2772
__do_sys_clone kernel/fork.c:2914 [inline]
__se_sys_clone kernel/fork.c:2898 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2898
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5322fc6b52
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007f532334fc60 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f532334fc60 RCX: 00007f5322fc6b52
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007f532334fdec R08: 0000000000000000 R09: 0000000000000001
R10: 0000555576c227d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 0000000000039654 R15: 00007f532334fe40
</TASK>
BUG: sleeping function called from invalid context at kernel/workqueue.c:4552
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5632, name: syz-executor
preempt_count: 103, expected: 0
RCU nest depth: 2, expected: 0
locks held by syz-executor/5632: 9, last CPU#1:
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1548 [inline]
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1601
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0 mm/mmap.c:1716
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0 mm/mmap.c:1723
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:347 [inline]
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pte_range mm/memory.c:1292 [inline]
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pmd_range+0x70f/0x5c50 mm/memory.c:1428
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid+0xba/0x490 include/linux/mmzone.h:2266
#8: ffffc90000a08cc0 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x5f0 kernel/time/timer.c:1745
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 1 UID: 0 PID: 5632 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
__might_resched+0x36a/0x4c0 kernel/sched/core.c:9234
__cancel_work_sync+0x6d/0x110 kernel/workqueue.c:4552
mmc_free_host+0x19/0x30 drivers/mmc/core/host.c:700
call_timer_fn+0x18d/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767
irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x222/0x350 kernel/locking/lockdep.c:5890
Code: ff ff ff e8 a0 20 39 0a f7 44 24 08 00 02 00 00 0f 84 39 ff ff ff 65 48 8b 05 f2 0b ce 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 cf 27 3c 0a cc 48 8d 3d a7 64 b9
RSP: 0018:ffffc90004307210 EFLAGS: 00000282
RAX: 2ab30850d67e6b00 RBX: 0000000000000000 RCX: 8000000000000003
RDX: 00000000dc7298f8 RSI: ffffffff8e4e132a RDI: ffffffff8c4cf580
RBP: ffffffff8242ba4a R08: ffffffff8242ba4a R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb5a420 R12: 0000000000000002
R13: ffffffff8eb5a420 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
pfn_valid+0xd6/0x490 include/linux/mmzone.h:2266
page_table_check_set+0x25/0x530 mm/page_table_check.c:105
page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
set_ptes include/linux/pgtable.h:447 [inline]
__copy_present_ptes mm/memory.c:1138 [inline]
copy_present_ptes mm/memory.c:1217 [inline]
copy_pte_range mm/memory.c:1340 [inline]
copy_pmd_range+0x4b46/0x5c50 mm/memory.c:1428
copy_pud_range mm/memory.c:1465 [inline]
copy_p4d_range mm/memory.c:1489 [inline]
copy_page_range+0xc25/0x1230 mm/memory.c:1575
dup_mmap+0xf17/0x1dc0 mm/mmap.c:1819
dup_mm kernel/fork.c:1549 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1601
copy_process+0x1e75/0x43e0 kernel/fork.c:2313
kernel_clone+0x2d7/0x940 kernel/fork.c:2772
__do_sys_clone kernel/fork.c:2914 [inline]
__se_sys_clone kernel/fork.c:2898 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2898
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5322fc6b52
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007f532334fc60 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f532334fc60 RCX: 00007f5322fc6b52
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007f532334fdec R08: 0000000000000000 R09: 0000000000000001
R10: 0000555576c227d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 0000000000039654 R15: 00007f532334fe40
</TASK>
=============================
WARNING: suspicious RCU usage
syzkaller #0 Tainted: G W L
-----------------------------
kernel/rcu/srcutree.c:1487 Illegal synchronize_srcu() in same-type SRCU (or in RCU) read-side critical section!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
locks held by syz-executor/5632: 9, last CPU#1:
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1548 [inline]
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1601
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0 mm/mmap.c:1716
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0 mm/mmap.c:1723
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:347 [inline]
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pte_range mm/memory.c:1292 [inline]
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pmd_range+0x70f/0x5c50 mm/memory.c:1428
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid+0xba/0x490 include/linux/mmzone.h:2266
#8: ffffc90000a08cc0 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x5f0 kernel/time/timer.c:1745
stack backtrace:
CPU: 1 UID: 0 PID: 5632 Comm: syz-executor Tainted: G W L syzkaller #0 PREEMPT(full)
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6894
__synchronize_srcu+0x157/0x2f0 kernel/rcu/srcutree.c:1483
wakeup_source_remove drivers/base/power/wakeup.c:201 [inline]
wakeup_source_unregister+0x129/0x3f0 drivers/base/power/wakeup.c:237
mmc_host_classdev_release+0x47/0x100 drivers/mmc/core/host.c:69
device_release+0xc4/0x1f0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x222/0x550 lib/kobject.c:737
call_timer_fn+0x18d/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767
irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x222/0x350 kernel/locking/lockdep.c:5890
Code: ff ff ff e8 a0 20 39 0a f7 44 24 08 00 02 00 00 0f 84 39 ff ff ff 65 48 8b 05 f2 0b ce 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 cf 27 3c 0a cc 48 8d 3d a7 64 b9
RSP: 0018:ffffc90004307210 EFLAGS: 00000282
RAX: 2ab30850d67e6b00 RBX: 0000000000000000 RCX: 8000000000000003
RDX: 00000000dc7298f8 RSI: ffffffff8e4e132a RDI: ffffffff8c4cf580
RBP: ffffffff8242ba4a R08: ffffffff8242ba4a R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb5a420 R12: 0000000000000002
R13: ffffffff8eb5a420 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
pfn_valid+0xd6/0x490 include/linux/mmzone.h:2266
page_table_check_set+0x25/0x530 mm/page_table_check.c:105
page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
set_ptes include/linux/pgtable.h:447 [inline]
__copy_present_ptes mm/memory.c:1138 [inline]
copy_present_ptes mm/memory.c:1217 [inline]
copy_pte_range mm/memory.c:1340 [inline]
copy_pmd_range+0x4b46/0x5c50 mm/memory.c:1428
copy_pud_range mm/memory.c:1465 [inline]
copy_p4d_range mm/memory.c:1489 [inline]
copy_page_range+0xc25/0x1230 mm/memory.c:1575
dup_mmap+0xf17/0x1dc0 mm/mmap.c:1819
dup_mm kernel/fork.c:1549 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1601
copy_process+0x1e75/0x43e0 kernel/fork.c:2313
kernel_clone+0x2d7/0x940 kernel/fork.c:2772
__do_sys_clone kernel/fork.c:2914 [inline]
__se_sys_clone kernel/fork.c:2898 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2898
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5322fc6b52
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007f532334fc60 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f532334fc60 RCX: 00007f5322fc6b52
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007f532334fdec R08: 0000000000000000 R09: 0000000000000001
R10: 0000555576c227d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 0000000000039654 R15: 00007f532334fe40
</TASK>
BUG: sleeping function called from invalid context at kernel/rcu/srcutree.c:1491
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5632, name: syz-executor
preempt_count: 103, expected: 0
RCU nest depth: 2, expected: 0
locks held by syz-executor/5632: 9, last CPU#1:
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1548 [inline]
#0: ffffffff8ec332d0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x10f/0x480 kernel/fork.c:1601
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff8880297203b8 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x195/0x1dc0 mm/mmap.c:1716
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff888022fb03b8 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x221/0x1dc0 mm/mmap.c:1723
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#3: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:347 [inline]
#4: ffff88801b0621f8 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8eb5a360 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pte_range mm/memory.c:1292 [inline]
#6: ffff88805b9e76d8 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pmd_range+0x70f/0x5c50 mm/memory.c:1428
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
#7: ffffffff8eb5a420 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid+0xba/0x490 include/linux/mmzone.h:2266
#8: ffffc90000a08cc0 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x5f0 kernel/time/timer.c:1745
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 1 UID: 0 PID: 5632 Comm: syz-executor Tainted: G W L syzkaller #0 PREEMPT(full)
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
__might_resched+0x36a/0x4c0 kernel/sched/core.c:9234
__synchronize_srcu+0x1a1/0x2f0 kernel/rcu/srcutree.c:1491
wakeup_source_remove drivers/base/power/wakeup.c:201 [inline]
wakeup_source_unregister+0x129/0x3f0 drivers/base/power/wakeup.c:237
mmc_host_classdev_release+0x47/0x100 drivers/mmc/core/host.c:69
device_release+0xc4/0x1f0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x222/0x550 lib/kobject.c:737
call_timer_fn+0x18d/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767
irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_acquire+0x222/0x350 kernel/locking/lockdep.c:5890
Code: ff ff ff e8 a0 20 39 0a f7 44 24 08 00 02 00 00 0f 84 39 ff ff ff 65 48 8b 05 f2 0b ce 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 cf 27 3c 0a cc 48 8d 3d a7 64 b9
RSP: 0018:ffffc90004307210 EFLAGS: 00000282
RAX: 2ab30850d67e6b00 RBX: 0000000000000000 RCX: 8000000000000003
RDX: 00000000dc7298f8 RSI: ffffffff8e4e132a RDI: ffffffff8c4cf580
RBP: ffffffff8242ba4a R08: ffffffff8242ba4a R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb5a420 R12: 0000000000000002
R13: ffffffff8eb5a420 R14: 0000000000000000 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:938 [inline]
pfn_valid+0xd6/0x490 include/linux/mmzone.h:2266
page_table_check_set+0x25/0x530 mm/page_table_check.c:105
page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
set_ptes include/linux/pgtable.h:447 [inline]
__copy_present_ptes mm/memory.c:1138 [inline]
copy_present_ptes mm/memory.c:1217 [inline]
copy_pte_range mm/memory.c:1340 [inline]
copy_pmd_range+0x4b46/0x5c50 mm/memory.c:1428
copy_pud_range mm/memory.c:1465 [inline]
copy_p4d_range mm/memory.c:1489 [inline]
copy_page_range+0xc25/0x1230 mm/memory.c:1575
dup_mmap+0xf17/0x1dc0 mm/mmap.c:1819
dup_mm kernel/fork.c:1549 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1601
copy_process+0x1e75/0x43e0 kernel/fork.c:2313
kernel_clone+0x2d7/0x940 kernel/fork.c:2772
__do_sys_clone kernel/fork.c:2914 [inline]
__se_sys_clone kernel/fork.c:2898 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2898
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5322fc6b52
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007f532334fc60 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f532334fc60 RCX: 00007f5322fc6b52
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007f532334fdec R08: 0000000000000000 R09: 0000000000000001
R10: 0000555576c227d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 0000000000039654 R15: 00007f532334fe40
</TASK>
ODEBUG: object ffffc90000a08a80 is NOT on stack ffffc90004300000, but annotated.
======================================================
----------------
Code disassembly (best guess), 2 bytes skipped:
0: ff ljmp (bad)
1: e8 a0 20 39 0a call 0xa3920a6
6: f7 44 24 08 00 02 00 testl $0x200,0x8(%rsp)
d: 00
e: 0f 84 39 ff ff ff je 0xffffff4d
14: 65 48 8b 05 f2 0b ce mov %gs:0x11ce0bf2(%rip),%rax # 0x11ce0c0e
1b: 11
1c: 48 3b 44 24 58 cmp 0x58(%rsp),%rax
21: 75 33 jne 0x56
23: fb sti
24: 48 83 c4 60 add $0x60,%rsp
* 28: 5b pop %rbx <-- trapping instruction
29: 41 5c pop %r12
2b: 41 5d pop %r13
2d: 41 5e pop %r14
2f: 41 5f pop %r15
31: 5d pop %rbp
32: e9 cf 27 3c 0a jmp 0xa3c2806
37: cc int3
38: 48 rex.W
39: 8d .byte 0x8d
3a: 3d .byte 0x3d
3b: a7 cmpsl %es:(%rdi),%ds:(%rsi)
3c: 64 fs
3d: b9 .byte 0xb9
---
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next reply other threads:[~2026-08-22 6:04 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-22 6:04 syzbot [this message]
2026-08-24 8:31 ` [syzbot] [mmc?] WARNING: suspicious RCU usage in mmc_free_host Adrian Hunter
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