[syzbot] BUG: sleeping function called from invalid context in break_ksm

[syzbot <syzbot+78a0878b3076f71313b3@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    acee3e83b493 Add linux-next specific files for 20221020
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15961f62880000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c82245cfb913f766
dashboard link: https://syzkaller.appspot.com/bug?extid=78a0878b3076f71313b3
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1255612c880000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12a1bed2880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98cc5896cded/disk-acee3e83.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b3d3eb3aa10a/vmlinux-acee3e83.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+78a0878b3076f71313b3@syzkaller.appspotmail.com

BUG: sleeping function called from invalid context at mm/ksm.c:500
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 3610, name: syz-executor212
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 0 PID: 3610 Comm: syz-executor212 Not tainted 6.1.0-rc1-next-20221020-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 __might_resched.cold+0x222/0x26b kernel/sched/core.c:9890
 break_ksm.part.0+0xbe/0x160 mm/ksm.c:500
 break_ksm mm/ksm.c:875 [inline]
 unmerge_ksm_pages+0x1a0/0x240 mm/ksm.c:881
 unmerge_and_remove_all_rmap_items mm/ksm.c:1021 [inline]
 run_store+0x3cf/0xa30 mm/ksm.c:2983
 kobj_attr_store+0x50/0x80 lib/kobject.c:824
 sysfs_kf_write+0x110/0x160 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x3f8/0x610 fs/kernfs/file.c:330
 call_write_iter include/linux/fs.h:2191 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x9e9/0xdd0 fs/read_write.c:584
 ksys_write+0x127/0x250 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fc23ce26b39
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff3f50c3a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc23ce26b39
RDX: 0000000000000002 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00007fc23cdeace0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc23cdead70
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


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