From: syzbot <syzbot+82a0a7de6d84867d030e@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 in mmc_free_host
Date: Wed, 19 Aug 2026 11:13:22 -0700 [thread overview]
Message-ID: <6a85f242.c8649fcc.3bb87.0014.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 8d3ae59288f1 Linux 7.2
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1797d6c6580000
kernel config: https://syzkaller.appspot.com/x/.config?x=2ca5f2f2c4197664
dashboard link: https://syzkaller.appspot.com/bug?extid=82a0a7de6d84867d030e
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: i386
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4dc2f356959b/disk-8d3ae592.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1a5c72c8e23c/vmlinux-8d3ae592.xz
kernel image: https://storage.googleapis.com/syzbot-assets/bc814d980581/bzImage-8d3ae592.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+82a0a7de6d84867d030e@syzkaller.appspotmail.com
------------[ cut here ]------------
do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff81880fbd>] do_wait+0x17d/0x510 kernel/exit.c:-1
WARNING: kernel/sched/core.c:9124 at __might_sleep+0x92/0xf0 kernel/sched/core.c:9120, CPU#0: syz-executor/16351
Modules linked in:
CPU: 0 UID: 0 PID: 16351 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
RIP: 0010:__might_sleep+0xac/0xf0 kernel/sched/core.c:9120
Code: 00 00 48 89 3c 24 41 89 f5 4c 8d 35 6e d3 c4 0e 43 80 3c 3c 00 74 08 48 89 df e8 bf 9b 9e 00 48 8b 0b 4c 89 f7 89 ee 48 89 ca <67> 48 0f b9 3a 44 89 ee 48 8b 3c 24 eb b5 44 89 f1 80 e1 07 80 c1
RSP: 0000:ffffc90000007c08 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88802fe5b770 RCX: ffffffff81880fbd
RDX: ffffffff81880fbd RSI: 0000000000000001 RDI: ffffffff905ae310
RBP: 0000000000000001 R08: ffffffff90578f37 R09: 1ffffffff20af1e6
R10: dffffc0000000000 R11: fffffbfff20af1e7 R12: 1ffff11005fcb6ee
R13: 0000000000001187 R14: ffffffff905ae310 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888124f49000(0063) knlGS:000000005776e480
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000003291fff8 CR3: 0000000055a7a000 CR4: 00000000003526f0
Call Trace:
<IRQ>
__cancel_work_sync+0x6d/0x110 kernel/workqueue.c:4487
mmc_free_host+0x19/0x30 drivers/mmc/core/host.c:700
call_timer_fn+0x192/0x5e0 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+0x225/0x840 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
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:do_raw_read_lock+0x4/0x90 kernel/locking/spinlock_debug.c:160
Code: 91 00 e9 e5 fe ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 <41> 56 53 48 89 fb 4c 8d 77 08 4c 89 f0 48 c1 e8 03 48 b9 00 00 00
RSP: 0000:ffffc900067c7b80 EFLAGS: 00000286
RAX: 2cb575fa076c2400 RBX: ffffc900067c7c80 RCX: 0000000080000001
RDX: 00000000d89f7662 RSI: ffffffff8e4b1d72 RDI: ffffffff8e80a040
RBP: ffff88802fe5b770 R08: ffffffff8187fba9 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8e80a058 R12: dffffc0000000000
R13: 1ffff92000cf8f90 R14: ffffc900067c7cb0 R15: 0000000000000004
__do_wait+0xd9/0x720 kernel/exit.c:1712
do_wait+0x1e7/0x510 kernel/exit.c:1756
kernel_wait4+0x232/0x2b0 kernel/exit.c:1915
__do_compat_sys_wait4 kernel/exit.c:1973 [inline]
__se_compat_sys_wait4 kernel/exit.c:1966 [inline]
__ia32_compat_sys_wait4+0x165/0x230 kernel/exit.c:1966
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
do_int80_emulation+0x19a/0x550 arch/x86/entry/syscall_32.c:172
asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:598
RIP: 0023:0xf71074eb
Code: 57 56 53 8b 44 24 14 f6 00 08 75 23 8b 44 24 18 8b 5c 24 1c 8b 4c 24 20 8b 54 24 24 8b 74 24 28 8b 7c 24 2c 8b 6c 24 30 cd 80 <5b> 5e 5f 5d c3 5b 5e 5f 5d e9 f7 a1 ff ff 66 90 66 90 66 90 90 53
RSP: 002b:00000000f74efc6c EFLAGS: 00000246 ORIG_RAX: 0000000000000072
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00000000f74efe08
RDX: 0000000040000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 48 89 3c 24 mov %rdi,(%rsp)
6: 41 89 f5 mov %esi,%r13d
9: 4c 8d 35 6e d3 c4 0e lea 0xec4d36e(%rip),%r14 # 0xec4d37e
10: 43 80 3c 3c 00 cmpb $0x0,(%r12,%r15,1)
15: 74 08 je 0x1f
17: 48 89 df mov %rbx,%rdi
1a: e8 bf 9b 9e 00 call 0x9e9bde
1f: 48 8b 0b mov (%rbx),%rcx
22: 4c 89 f7 mov %r14,%rdi
25: 89 ee mov %ebp,%esi
27: 48 89 ca mov %rcx,%rdx
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 44 89 ee mov %r13d,%esi
32: 48 8b 3c 24 mov (%rsp),%rdi
36: eb b5 jmp 0xffffffed
38: 44 89 f1 mov %r14d,%ecx
3b: 80 e1 07 and $0x7,%cl
3e: 80 .byte 0x80
3f: c1 .byte 0xc1
---
This report is generated by a bot. It may contain errors.
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reply other threads:[~2026-08-19 18:13 UTC|newest]
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