[syzbot] [mm?] BUG: soft lockup in generic_file_write_iter (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1a0beef98b58 Merge tag 'tpmdd-v6.4-rc1' of git://git.kerne..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1744b894280000
kernel config: https://syzkaller.appspot.com/x/.config?x=3aa4ca13c88f2286
dashboard link: https://syzkaller.appspot.com/bug?extid=3b5bce3e397a2c9dcac6
compiler: aarch64-linux-gnu-gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3b5bce...@syzkaller.appspotmail.com

watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [syz-executor.0:3202]
Modules linked in:
irq event stamp: 50116
hardirqs last enabled at (50115): [<ffff80000ca7e160>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:84 [inline]
hardirqs last enabled at (50115): [<ffff80000ca7e160>] exit_to_kernel_mode+0x38/0x120 arch/arm64/kernel/entry-common.c:94
hardirqs last disabled at (50116): [<ffff80000ca7fdc8>] __el1_irq arch/arm64/kernel/entry-common.c:468 [inline]
hardirqs last disabled at (50116): [<ffff80000ca7fdc8>] el1_interrupt+0x24/0x54 arch/arm64/kernel/entry-common.c:486
softirqs last enabled at (50020): [<ffff80000801080c>] _stext+0x80c/0xd70
softirqs last disabled at (49871): [<ffff800008019484>] ____do_softirq+0x10/0x1c arch/arm64/kernel/irq.c:80
CPU: 1 PID: 3202 Comm: syz-executor.0 Not tainted 6.3.0-syzkaller-00113-g1a0beef98b58 #0
Hardware name: linux,dummy-virt (DT)
pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __arch_copy_from_user+0x1b0/0x230 arch/arm64/lib/copy_template.S:164
lr : copyin lib/iov_iter.c:183 [inline]
lr : copyin+0xb8/0x118 lib/iov_iter.c:175
sp : ffff8000192a7840
x29: ffff8000192a7840 x28: ffff8000192a7c30 x27: ffff80000dddb378
x26: 0000000000001000 x25: 0000000040000000 x24: ffff000006324000
x23: 0000ffff99400000 x22: 0000ffff99454000 x21: ffff000006324000
x20: 0000ffff99454000 x19: 0000000000001000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: 0000ffff99454000
x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff000006324d80
x5 : ffff000006325000 x4 : 0000000000000000 x3 : ffff80000910e070
x2 : 0000000000000200 x1 : 0000ffff99454dc0 x0 : ffff000006324000
Call trace:
__arch_copy_from_user+0x1b0/0x230 arch/arm64/lib/copy_template.S:158
copy_page_from_iter_atomic+0x33c/0xe5c lib/iov_iter.c:815
generic_perform_write+0x218/0x3ec mm/filemap.c:3934
__generic_file_write_iter+0x1e8/0x3a0 mm/filemap.c:4054
generic_file_write_iter+0xc0/0x294 mm/filemap.c:4086
call_write_iter include/linux/fs.h:1851 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x4c8/0x740 fs/read_write.c:584
ksys_write+0xec/0x1d0 fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__arm64_sys_write+0x6c/0x9c fs/read_write.c:646
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x6c/0x260 arch/arm64/kernel/syscall.c:52
el0_svc_common.constprop.0+0xc4/0x254 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x50/0x124 arch/arm64/kernel/syscall.c:193
el0_svc+0x54/0x140 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0xb8/0xbc arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.