[v6.6] INFO: rcu detected stall in vfs_fileattr_set

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 80de0a958133 Linux 6.6.133
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1734b6ba580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c5b35c4db8465904
dashboard link: https://syzkaller.appspot.com/bug?extid=fef660ae9ed5f3a55966
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3a04f1ef21aa/disk-80de0a95.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/081f2fcfce9b/vmlinux-80de0a95.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3ef5904d5301/bzImage-80de0a95.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fef660...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 1-....: (10500 ticks this GP) idle=8544/1/0x4000000000000000 softirq=12272/12272 fqs=5051
rcu: hardirqs softirqs csw/system
rcu: number: 2820663 0 0
rcu: cputime: 34600 17879 32 ==> 52500(ms)
rcu: (t=10502 jiffies g=11461 q=933 ncpus=2)
CPU: 1 PID: 6099 Comm: syz.3.73 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:jhash+0x2d3/0x740 include/linux/jhash.h:88
Code: 00 00 41 83 ff 09 0f 85 d6 02 00 00 e8 46 62 5d fd 48 ba 00 00 00 00 00 fc ff df e9 5c 01 00 00 41 83 ff 04 0f 84 a2 00 00 00 <41> 83 ff 05 0f 84 e5 00 00 00 41 83 ff 06 0f 85 a4 02 00 00 e8 14
RSP: 0018:ffffc900001f07c8 EFLAGS: 00000202
RAX: 000000000000000c RBX: 00000000d24d8ce0 RCX: 0000000000000005
RDX: ffffffff8429bf23 RSI: ffffffff8d7d4a40 RDI: 0000000000000006
RBP: 00000000d24d8ce0 R08: ffff888029210000 R09: 000000000000000c
R10: 000000000000000c R11: 0000000000000100 R12: 00000000d24d8ce0
R13: dffffc0000000000 R14: ffff88805fc4d3da R15: 0000000000000006
FS: 00007fb16770b6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056450c9c6f30 CR3: 000000007523b000 CR4: 00000000003506e0
Call Trace:
<IRQ>
rht_key_get_hash include/linux/rhashtable.h:133 [inline]
rht_key_hashfn include/linux/rhashtable.h:159 [inline]
__rhashtable_lookup include/linux/rhashtable.h:604 [inline]
rhltable_lookup+0x24f/0x7c0 include/linux/rhashtable.h:696
sta_info_hash_lookup net/mac80211/sta_info.c:193 [inline]
sta_info_get_bss+0x12a/0x320 net/mac80211/sta_info.c:230
ieee80211_rx_for_interface net/mac80211/rx.c:5117 [inline]
__ieee80211_rx_handle_packet net/mac80211/rx.c:5298 [inline]
ieee80211_rx_list+0x28dc/0x32d0 net/mac80211/rx.c:5437
ieee80211_rx_napi+0x1b2/0x3d0 net/mac80211/rx.c:5460
ieee80211_rx include/net/mac80211.h:4971 [inline]
ieee80211_handle_queued_frames+0x106/0x1a0 net/mac80211/main.c:319
tasklet_action_common+0x302/0x4d0 kernel/softirq.c:809
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:raw_spin_rq_unlock_irq+0x13/0x90 kernel/sched/sched.h:1392
Code: 5d 41 5e 41 5f 5d c3 e8 6b 45 27 09 66 2e 0f 1f 84 00 00 00 00 00 90 41 57 41 56 53 66 90 e8 e4 ee 30 09 e8 cf b4 2e 00 fb 5b <41> 5e 41 5f c3 49 be 00 00 00 00 00 fc ff df 49 89 ff 48 8d 9f 58
RSP: 0018:ffffc900053ef348 EFLAGS: 00000286
RAX: d316d900c1a01400 RBX: ffff8880b8f3cd48 RCX: d316d900c1a01400
RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: ffffffff8b1c8de0
RBP: ffffc900053ef570 R08: ffffffff911c45af R09: 1ffffffff22388b5
R10: dffffc0000000000 R11: fffffbfff22388b6 R12: dffffc0000000000
R13: ffff888029210000 R14: ffff8880b8f3c000 R15: ffff888029210000
__schedule+0x179f/0x45a0 kernel/sched/core.c:6704
preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:692
RIP: 0010:schedule+0xac/0x170 kernel/sched/core.c:6773
Code: f7 e8 78 f2 50 f7 49 8b 3e 48 85 ff 74 0a be 01 00 00 00 e8 f6 13 7e f9 49 89 de 49 c1 ee 03 eb 09 48 f7 03 08 00 00 00 74 2c <bf> 01 00 00 00 e8 4a 20 ce f6 31 ff e8 a3 b9 ff ff bf 01 00 00 00
RSP: 0018:ffffc900053ef6f8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffff888029210000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 00000000ffffffff
RBP: ffffc900053ef910 R08: ffffffff911c45af R09: 1ffffffff22388b5
R10: dffffc0000000000 R11: fffffbfff22388b6 R12: 0000000000000002
R13: ffff88802522f4d0 R14: 1ffff11005242000 R15: dffffc0000000000
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6833
rwsem_down_write_slowpath+0xc05/0xff0 kernel/locking/rwsem.c:1178
__down_write_common kernel/locking/rwsem.c:1306 [inline]
__down_write kernel/locking/rwsem.c:1315 [inline]
down_write+0x1b9/0x200 kernel/locking/rwsem.c:1574
inode_lock include/linux/fs.h:804 [inline]
vfs_fileattr_set+0x154/0xb10 fs/ioctl.c:682
ioctl_fssetxattr fs/ioctl.c:759 [inline]
do_vfs_ioctl+0x13fa/0x1cc0 fs/ioctl.c:846
__do_sys_ioctl fs/ioctl.c:869 [inline]
__se_sys_ioctl+0x83/0x170 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb16679c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb16770b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fb166a15fa0 RCX: 00007fb16679c819
RDX: 00002000000001c0 RSI: 00000000401c5820 RDI: 000000000000000c
RBP: 00007fb166832c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb166a16038 R14: 00007fb166a15fa0 R15: 00007ffc1d3db7d8
</TASK>


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