Re: [syzbot] WARNING in dev_watchdog (2)

From: syzbot
Date: Sat Dec 11 2021 - 03:02:24 EST

syzbot has found a reproducer for the following issue on:

HEAD commit: b8a98b6bf66a Merge tag 'pci-v5.16-fixes-2' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12fa7fc5b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=7d5e878e3399b6cc
dashboard link: https://syzkaller.appspot.com/bug?extid=d55372214aff0faa1f1f
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1068a551b00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1146706db00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d55372214aff0faa1f1f@xxxxxxxxxxxxxxxxxxxxxxxxx

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NETDEV WATCHDOG: sl14 (): transmit queue 0 timed out
WARNING: CPU: 1 PID: 20260 at net/sched/sch_generic.c:478 dev_watchdog+0x81d/0x860 net/sched/sch_generic.c:477
Modules linked in:
CPU: 1 PID: 20260 Comm: dhcpcd-run-hook Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:dev_watchdog+0x81d/0x860 net/sched/sch_generic.c:477
Code: 99 51 44 f9 c6 05 0d 02 ab 05 01 4c 89 e7 e8 ba fd e2 ff 48 c7 c7 e0 fb 9c 8b 4c 89 e6 48 89 c2 44 89 e9 31 c0 e8 33 2b 0e f9 <0f> 0b e9 2b fe ff ff 44 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c 3c fc
RSP: 0018:ffffc90000dc0b40 EFLAGS: 00010246
RAX: 994dcd9ba1567700 RBX: 00000000ffffddd0 RCX: ffff8880a7b69d00
RDX: 0000000000000102 RSI: 0000000000000102 RDI: 0000000000000000
RBP: 00000000ffffde41 R08: ffffffff816a1d52 R09: fffff520001b80b9
R10: fffff520001b80b9 R11: 0000000000000000 R12: ffff88807dc5e000
R13: 0000000000000000 R14: ffff88807a490068 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562f1294c000 CR3: 0000000179f36000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
call_timer_fn+0xf6/0x210 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers+0x71a/0x910 kernel/time/timer.c:1734
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1747
__do_softirq+0x392/0x7a3 kernel/softirq.c:558
__irq_exit_rcu+0xec/0x170 kernel/softirq.c:637
irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0010:get_flush_tlb_info arch/x86/mm/tlb.c:966 [inline]
RIP: 0010:flush_tlb_mm_range+0x1a2/0x490 arch/x86/mm/tlb.c:1004
Code: e8 03 80 3c 18 00 74 05 e8 6b 78 94 00 4d 89 7d 10 4c 89 e8 48 c1 e8 03 80 3c 18 00 74 08 4c 89 ef e8 52 78 94 00 48 8b 04 24 <49> 89 45 00 49 8d 7d 24 48 89 f8 48 c1 e8 03 8a 04 18 84 c0 0f 85
RSP: 0018:ffffc90020abf660 EFLAGS: 00000246
RAX: ffff888152e71500 RBX: dffffc0000000000 RCX: dffffc0000000000
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8880b9b38d90
RBP: ffffc90020abf720 R08: dffffc0000000000 R09: ffffed102a5ce325
R10: ffffed102a5ce325 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8880b9b38d80 R14: 0000000000000009 R15: ffffffffffffffff
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:426 [inline]
tlb_flush_mmu+0x1a7/0x910 mm/mmu_gather.c:248
tlb_finish_mmu+0xcb/0x200 mm/mmu_gather.c:340
exit_mmap+0x3dd/0x6f0 mm/mmap.c:3172
__mmput+0x111/0x3a0 kernel/fork.c:1113
exec_mmap+0x589/0x610 fs/exec.c:1028
begin_new_exec+0x6c9/0x1180 fs/exec.c:1286
load_elf_binary+0x851/0x3c60 fs/binfmt_elf.c:1001
search_binary_handler fs/exec.c:1723 [inline]
exec_binprm fs/exec.c:1764 [inline]
bprm_execve+0x8eb/0x1470 fs/exec.c:1833
do_execveat_common+0x44c/0x590 fs/exec.c:1922
do_execve fs/exec.c:1990 [inline]
__do_sys_execve fs/exec.c:2066 [inline]
__se_sys_execve fs/exec.c:2061 [inline]
__x64_sys_execve+0x8e/0xa0 fs/exec.c:2061
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fb90670f337
Code: Unable to access opcode bytes at RIP 0x7fb90670f30d.
RSP: 002b:00007ffd8df132e8 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 0000562f1294bf28 RCX: 00007fb90670f337
RDX: 0000562f1294bf78 RSI: 0000562f1294bf28 RDI: 0000562f1294c000
RBP: 0000562f1294c000 R08: 0000562f1294c009 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000562f1294bf78
R13: 00007fb9068b4ff4 R14: 0000562f1294bf78 R15: 0000000000000000
</TASK>
----------------
Code disassembly (best guess):
0: e8 03 80 3c 18 callq 0x183c8008
5: 00 74 05 e8 add %dh,-0x18(%rbp,%rax,1)
9: 6b 78 94 00 imul $0x0,-0x6c(%rax),%edi
d: 4d 89 7d 10 mov %r15,0x10(%r13)
11: 4c 89 e8 mov %r13,%rax
14: 48 c1 e8 03 shr $0x3,%rax
18: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1)
1c: 74 08 je 0x26
1e: 4c 89 ef mov %r13,%rdi
21: e8 52 78 94 00 callq 0x947878
26: 48 8b 04 24 mov (%rsp),%rax
* 2a: 49 89 45 00 mov %rax,0x0(%r13) <-- trapping instruction
2e: 49 8d 7d 24 lea 0x24(%r13),%rdi
32: 48 89 f8 mov %rdi,%rax
35: 48 c1 e8 03 shr $0x3,%rax
39: 8a 04 18 mov (%rax,%rbx,1),%al
3c: 84 c0 test %al,%al
3e: 0f .byte 0xf
3f: 85 .byte 0x85