bisecting fixing commit since 7cc2a8ea104820dd9e702202621e8fd4d9f6c8cf building syzkaller on 510951950dc0ee69cfdaf746061d3dbe31b49fd8 testing commit 7cc2a8ea104820dd9e702202621e8fd4d9f6c8cf with gcc (GCC) 8.4.1 20210217 kernel signature: 1a1d2595ef8b42cb606e33e16b65cfdcc5769cddd33209112c5bdb2507607901 all runs: crashed: WARNING in generic_make_request_checks testing current HEAD 17ae69aba89dbfa2139b7f8024b757ab3cc42f59 testing commit 17ae69aba89dbfa2139b7f8024b757ab3cc42f59 with gcc (GCC) 10.2.1 20210217 kernel signature: 86655f9d3d29234b2a09812fec9549bd2cae18d874e290c4915c65eca0faf805 all runs: crashed: WARNING in submit_bio_checks revisions tested: 2, total time: 19m52.187237024s (build: 12m37.613719981s, test: 6m16.233488168s) the crash still happens on HEAD commit msg: Merge tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security crash: WARNING in submit_bio_checks ------------[ cut here ]------------ Trying to write to read-only block-device nullb0 (partno 0) WARNING: CPU: 1 PID: 7366 at block/blk-core.c:704 bio_check_ro block/blk-core.c:704 [inline] WARNING: CPU: 1 PID: 7366 at block/blk-core.c:704 submit_bio_checks+0x7de/0x1680 block/blk-core.c:817 Modules linked in: CPU: 1 PID: 7366 Comm: syz-executor.2 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bio_check_ro block/blk-core.c:704 [inline] RIP: 0010:submit_bio_checks+0x7de/0x1680 block/blk-core.c:817 Code: b6 90 e0 05 00 00 48 8d 74 24 58 4c 89 ff 89 54 24 08 e8 35 76 fe ff 8b 54 24 08 48 c7 c7 40 47 11 88 48 89 c6 e8 8f f2 03 04 <0f> 0b e9 22 fb ff ff 48 b8 00 00 00 00 00 fc ff df 48 8b 14 24 48 RSP: 0018:ffffc90003d07158 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 1ffff920007a0e32 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff881325e0 RDI: fffff520007a0e1d RBP: ffff88810d0ff020 R08: 0000000000000001 R09: ffff8881f6530dc7 R10: ffffed103eca61b8 R11: 7420676e69797254 R12: ffff88810c21a290 R13: ffff88810d0ff524 R14: ffff88810ccec000 R15: ffff88810c21a280 FS: 0000000000000000(0000) GS:ffff8881f6500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000000 CR3: 000000010fe39005 CR4: 00000000001706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: submit_bio_noacct+0x79/0xdb0 block/blk-core.c:1032 submit_bio+0xdf/0x4b0 block/blk-core.c:1118 submit_bh_wbc+0x4e9/0x6a0 fs/buffer.c:3055 __block_write_full_page+0x614/0xdd0 fs/buffer.c:1810 __writepage+0x58/0x140 mm/page-writeback.c:2311 write_cache_pages+0x52b/0xd00 mm/page-writeback.c:2246 generic_writepages mm/page-writeback.c:2337 [inline] generic_writepages+0xd7/0x140 mm/page-writeback.c:2326 do_writepages+0xca/0x240 mm/page-writeback.c:2352 __filemap_fdatawrite_range+0x247/0x320 mm/filemap.c:424 filemap_write_and_wait_range mm/filemap.c:700 [inline] filemap_write_and_wait_range+0xac/0x150 mm/filemap.c:694 filemap_write_and_wait include/linux/fs.h:2894 [inline] __sync_blockdev fs/block_dev.c:526 [inline] sync_blockdev fs/block_dev.c:535 [inline] __blkdev_put+0x59b/0x6c0 fs/block_dev.c:1569 blkdev_put+0x75/0x480 fs/block_dev.c:1638 blkdev_close+0x8b/0xd0 fs/block_dev.c:1646 __fput+0x209/0x870 fs/file_table.c:280 task_work_run+0xc0/0x160 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xac8/0x25b0 kernel/exit.c:826 do_group_exit+0xe7/0x290 kernel/exit.c:923 get_signal+0x3c0/0x1b50 kernel/signal.c:2818 arch_do_signal_or_restart+0x2a8/0x1f80 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x202/0x280 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x40/0x80 kernel/entry/common.c:301 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:57 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4645a9 Code: Unable to access opcode bytes at RIP 0x46457f. RSP: 002b:00007fd24fd39218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 000000000055bfa8 RCX: 00000000004645a9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000055bfac RBP: 000000000055bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055bfac R13: 00007ffe4258015f R14: 00007fd24fd39300 R15: 0000000000022000 irq event stamp: 5417 hardirqs last enabled at (5541): [] console_unlock+0x72b/0x9c0 kernel/printk/printk.c:2668 hardirqs last disabled at (5562): [] __schedule+0x1411/0x2400 kernel/sched/core.c:5043 softirqs last enabled at (5652): [] invoke_softirq kernel/softirq.c:433 [inline] softirqs last enabled at (5652): [] __irq_exit_rcu kernel/softirq.c:637 [inline] softirqs last enabled at (5652): [] irq_exit_rcu+0x250/0x2a0 kernel/softirq.c:649 softirqs last disabled at (5667): [] invoke_softirq kernel/softirq.c:433 [inline] softirqs last disabled at (5667): [] __irq_exit_rcu kernel/softirq.c:637 [inline] softirqs last disabled at (5667): [] irq_exit_rcu+0x250/0x2a0 kernel/softirq.c:649 ---[ end trace 2f508e3c33d5bc4b ]---