[syzbot] [block?] WARNING in blk_mq_start_request

From: syzbot
Date: Tue Nov 07 2023 - 02:29:29 EST


Hello,

syzbot found the following issue on:

HEAD commit: 4652b8e4f3ff Merge tag '6.7-rc-ksmbd-server-fixes' of git:..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=117a6ebb680000
kernel config: https://syzkaller.appspot.com/x/.config?x=5316ad879647e3c5
dashboard link: https://syzkaller.appspot.com/bug?extid=fcc47ba2476570cbbeb0
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13489af3680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=145c7d07680000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-4652b8e4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9c5be65b1bc8/vmlinux-4652b8e4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8799a4da0be5/bzImage-4652b8e4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fcc47ba2476570cbbeb0@xxxxxxxxxxxxxxxxxxxxxxxxx

R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffff489c59c
R13: 00007ffff489c5b0 R14: 00007ffff489c5f0 R15: 0000000000000003
</TASK>
------------[ cut here ]------------
WARNING: CPU: 3 PID: 5178 at block/blk-mq.c:1258 blk_mq_start_request+0x643/0x780 block/blk-mq.c:1258
Modules linked in:
CPU: 3 PID: 5178 Comm: syz-executor268 Not tainted 6.6.0-syzkaller-10396-g4652b8e4f3ff #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:blk_mq_start_request+0x643/0x780 block/blk-mq.c:1258
Code: 00 00 fc ff df 48 8d 7d 10 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 2f 01 00 00 48 89 df ff 55 10 e9 64 fc ff ff e8 1d 9c 44 fd <0f> 0b e9 f6 fa ff ff e8 11 9c 44 fd 0f 0b e9 06 fa ff ff e8 05 9c
RSP: 0018:ffffc900035ef298 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888018539e00 RCX: ffffffff8442db37
RDX: ffff888030114f00 RSI: ffffffff8442e043 RDI: 0000000000000005
RBP: ffff888018539e94 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888106a33350
R13: 0000000000000001 R14: ffff888018539f1d R15: ffff888018539f20
FS: 0000555555f00480(0000) GS:ffff88806b900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555555f00788 CR3: 000000002238a000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
null_queue_rq+0x2e2/0x7a0 drivers/block/null_blk/main.c:1727
__blk_mq_issue_directly+0xe3/0x270 block/blk-mq.c:2578
blk_mq_request_issue_directly+0x120/0x190 block/blk-mq.c:2663
blk_mq_plug_issue_direct+0x19e/0x670 block/blk-mq.c:2684
blk_mq_flush_plug_list.part.0+0x16b6/0x1e90 block/blk-mq.c:2793
blk_mq_flush_plug_list+0x62/0x80 block/blk-mq.c:2770
__blk_flush_plug+0x2c0/0x430 block/blk-core.c:1142
blk_finish_plug block/blk-core.c:1166 [inline]
blk_finish_plug+0x54/0xa0 block/blk-core.c:1163
read_pages+0x69b/0xdb0 mm/readahead.c:183
page_cache_ra_unbounded+0x457/0x5e0 mm/readahead.c:269
do_page_cache_ra mm/readahead.c:299 [inline]
page_cache_ra_order+0x72b/0xa80 mm/readahead.c:546
ondemand_readahead+0x493/0x1130 mm/readahead.c:668
page_cache_sync_ra+0x174/0x1d0 mm/readahead.c:695
page_cache_sync_readahead.constprop.0+0xb2/0xf0 include/linux/pagemap.h:1293
cramfs_blkdev_read fs/cramfs/inode.c:218 [inline]
cramfs_read+0x33f/0xae0 fs/cramfs/inode.c:278
cramfs_read_super+0xbd/0x9b0 fs/cramfs/inode.c:522
cramfs_blkdev_fill_super+0x116/0x2f0 fs/cramfs/inode.c:622
get_tree_bdev+0x3b5/0x650 fs/super.c:1595
cramfs_get_tree fs/cramfs/inode.c:958 [inline]
cramfs_get_tree+0x40/0x50 fs/cramfs/inode.c:948
vfs_get_tree+0x8c/0x370 fs/super.c:1768
do_new_mount fs/namespace.c:3337 [inline]
path_mount+0x1492/0x1ed0 fs/namespace.c:3664
do_mount fs/namespace.c:3677 [inline]
__do_sys_mount fs/namespace.c:3886 [inline]
__se_sys_mount fs/namespace.c:3863 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:3863
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7feca35df9f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 1a 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffff489c548 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007ffff489c550 RCX: 00007feca35df9f9
RDX: 0000000020000040 RSI: 00000000200000c0 RDI: 0000000020000000
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000003134
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffff489c59c
R13: 00007ffff489c5b0 R14: 00007ffff489c5f0 R15: 0000000000000003
</TASK>


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