bisecting cause commit starting from 7c832d2f9b959e3181370c8b0dacaf9efe13fc05 building syzkaller on 0c5d9412d774262384cbdbe9d672b077364ed776 testing commit 7c832d2f9b959e3181370c8b0dacaf9efe13fc05 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 2c741ddeb7fc67524c922aaa5c48c13160e428aae5fafa5e45db74e614c0a53b all runs: crashed: INFO: task can't die in ext4_stop_mmpd testing release v5.14 testing commit 7d2a07b769330c34b4deabeed939325c77a7ec2f compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: de5d0644639cc5c360c5e4129b2c3253ccb03fa29846cb1eb6936ee1da8e68ac all runs: crashed: INFO: task hung in ext4_stop_mmpd testing release v5.13 testing commit 62fb9874f5da54fdb243003b386128037319b219 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: f0d89eb8f9d4c9864735171e2eb3e5feeaf7d26439e5a7bae1ef45fb8f9578ab all runs: crashed: INFO: task hung in ext4_fill_super testing release v5.12 testing commit 9f4ad9e425a1d3b6a34617b8ea226d56a119a717 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: f3685dd148c0d7f62ec2c26b6ccd338a86cdce80e434ce6a225cc94922f0c2db all runs: crashed: INFO: task hung in ext4_fill_super testing release v5.11 testing commit f40ddce88593482919761f74910f42f4b84c004b compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 1f5c2551444cc5a9717d44acd7d59dea64de831f0ec6d140c76c393b1a8be7b9 run #0: crashed: WARNING: ODEBUG bug in ext4_fill_super run #1: crashed: WARNING: ODEBUG bug in ext4_fill_super run #2: crashed: WARNING: ODEBUG bug in ext4_fill_super run #3: crashed: WARNING: ODEBUG bug in ext4_fill_super run #4: crashed: WARNING: ODEBUG bug in ext4_fill_super run #5: crashed: WARNING: ODEBUG bug in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: crashed: WARNING: ODEBUG bug in ext4_fill_super run #8: crashed: INFO: task hung in ext4_fill_super run #9: crashed: INFO: task hung in ext4_fill_super testing release v5.10 testing commit 2c85ebc57b3e1817b6ce1a6b703928e113a90442 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 6fadf1b92bad0f2eefaa047034d1044e5b34f9c1872d7811646aed5049f137a7 all runs: crashed: INFO: task hung in ext4_fill_super testing release v5.9 testing commit bbf5c979011a099af5dc76498918ed7df445635b compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 79f11e7a8eed3e447672927cef5561c2ba920551ad72927757519c7fec1a8d58 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: OK run #8: OK run #9: OK testing release v5.8 testing commit bcf876870b95592b52519ed4aafcf9d95999bc9c compiler: gcc (GCC) 8.4.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 3a10be75bbfb45817efdf085ef0d7bb7934a9655779dbb5140e82be0f1d7e80e run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v5.7 testing commit 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 compiler: gcc version 8.4.1 20210217 (GCC), GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 6c15458155203600f9eead46349048b82bfa958d35a9c08152de83a646393e6d run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: OK run #8: OK run #9: OK testing release v5.6 testing commit 7111951b8d4973bda27ff663f2cf18b663d15b48 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 3ec8f747eafa1b5378a4cc37ea09f1a8798bfd8f4ee7c3e4b1f24c42b3888ba2 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v5.5 testing commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 1e50721387abc6962be73a376a0e25993de05554e109369a0cf0059deb740472 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: OK run #7: OK run #8: OK run #9: OK testing release v5.4 testing commit 219d54332a09e8d8741c1e1982f5eae56099de85 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 9746f3b655633436e9e0647dfbf6f8cc6036487689cc04d539ee7143aa30fdd9 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: OK run #6: OK run #7: OK run #8: OK run #9: OK testing release v5.3 testing commit 4d856f72c10ecb060868ed10ff1b1453943fc6c8 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 54920ccfe5023ac1310b5de92553c4d02e1b7ef19a40c59ae996f8f35d0795ad run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: crashed: INFO: task hung in ext4_fill_super run #8: OK run #9: OK testing release v5.2 testing commit 0ecfebd2b52404ae0c54a878c872bb93363ada36 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 63727acb5f1a8479cf00e4aeaeb8b93f969f620cc11da3adce5ab8324955b755 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #6: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #7: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #8: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #9: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! testing release v5.1 testing commit e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 7050ee04822f2db21ebf0899802481c3b2ef8a9ecc304d7dd18796d74cadf966 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #6: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #7: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #8: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! run #9: crashed: BUG: MAX_STACK_TRACE_ENTRIES too low! testing release v5.0 testing commit 1c163f4c7b3f621efff9b28a47abb36f7378d783 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 74b9cbc5d612f13207febb901e714d31acb8cf018ab074f1a6cc514f3f821600 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: crashed: INFO: task hung in ext4_fill_super run #8: crashed: INFO: task hung in ext4_fill_super run #9: OK testing release v4.20 testing commit 8fe28cb58bcb235034b64cbbb7550a8a43fd88be compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: fe81d1b841209a3422a29140241a26a8703e459d169b3c9244933bb1a8c21f1b run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: crashed: INFO: task hung in ext4_fill_super run #8: crashed: INFO: task hung in ext4_fill_super run #9: OK testing release v4.19 testing commit 84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 1e571a47fcda6873269a9cc1b9bdeed87d9279ab7ba23150c501b3fd9d0a6ad4 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: crashed: INFO: task hung in ext4_fill_super run #8: crashed: INFO: task hung in ext4_fill_super run #9: OK testing release v4.18 testing commit 94710cac0ef4ee177a63b5227664b38c95bbf703 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: 6f8e9c744989ffba4f0c73cdcacb6ead39b9ed1d66784076b4690ea87f509729 run #0: crashed: INFO: task hung in ext4_fill_super run #1: crashed: INFO: task hung in ext4_fill_super run #2: crashed: INFO: task hung in ext4_fill_super run #3: crashed: INFO: task hung in ext4_fill_super run #4: crashed: INFO: task hung in ext4_fill_super run #5: crashed: INFO: task hung in ext4_fill_super run #6: crashed: INFO: task hung in ext4_fill_super run #7: crashed: INFO: task hung in ext4_fill_super run #8: crashed: INFO: task hung in ext4_fill_super run #9: OK testing release v4.17 testing commit 29dcea88779c856c7dc92040a0c01233263101d4 compiler: gcc (GCC) 8.4.1 20210217 failed to run ["make" "-j" "64" "ARCH=x86_64" "CC=/syzkaller/shared/bisect_bin/gcc-8.1.0/bin/gcc" "bzImage"]: exit status 2 testing release v4.16 testing commit 0adb32858b0bddf4ada5f364a84ed60b196dbcda compiler: gcc (GCC) 8.4.1 20210217 orc_dump.c:106:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:111:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] elf.c:135:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:140:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] testing release v4.15 testing commit d8a5b80568a9cb66810e75b182018e9edb68e8ff compiler: gcc (GCC) 8.4.1 20210217 orc_dump.c:106:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:111:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] elf.c:135:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:140:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:36:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.14 testing commit bebc6082da0a9f5d47a1ea2edc099bf671058bd4 compiler: gcc (GCC) 8.4.1 20210217 orc_dump.c:105:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] orc_dump.c:110:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:139:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:36:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.13 testing commit 569dbb88e80deb68974ef6fdd6a13edb9d686261 compiler: gcc (GCC) 8.4.1 20210217 pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:144:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:149:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] testing release v4.12 testing commit 6f7da290413ba713f0cdd9ff1a2a9bb129ef4f6c compiler: gcc (GCC) 8.4.1 20210217 pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] elf.c:141:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:146:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] testing release v4.11 testing commit a351e9b9fc24e982ec2f0e76379a49826036da12 compiler: gcc (GCC) 7.5.0 elf.c:141:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:146:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.10 testing commit c470abd4fde40ea6a0846a2beab642a578c0b8cd compiler: gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.9 testing commit 69973b830859bc6529a7a0468ba0d80ee5117826 compiler: gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:35:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.8 testing commit c8d2bc9bc39ebea8437fd974fdbc21847bb897a3 compiler: gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:129:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:134:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.7 testing commit 523d939ef98fd712632d93a5a2b588e477a7565e compiler: gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] elf.c:122:2: error: 'elf_getshnum' is deprecated [-Werror=deprecated-declarations] elf.c:127:2: error: 'elf_getshstrndx' is deprecated [-Werror=deprecated-declarations] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] testing release v4.6 testing commit 2dcd0af568b0cf583645c8a317dd12e344b1c72a compiler: gcc (GCC) 5.5.0 tools/include/linux/log2.h:19:1: error: ignoring attribute 'noreturn' because it conflicts with attribute 'const' [-Werror=attributes] pager.c:33:12: error: passing argument 2 to 'restrict'-qualified parameter aliases with argument 4 [-Werror=restrict] revisions tested: 19, total time: 5h28m43.16084141s (build: 2h3m8.606421599s, test: 3h19m30.397194522s) the crash already happened on the oldest tested release commit msg: Linux 4.18 crash: INFO: task hung in ext4_fill_super EXT4-fs error (device loop0): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop3): mount failed EXT4-fs (loop0): get root inode failed EXT4-fs (loop0): mount failed EXT4-fs error (device loop4): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated INFO: task syz-executor.2:5844 blocked for more than 140 seconds. Not tainted 4.18.0-syzkaller #0 EXT4-fs (loop4): get root inode failed "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. EXT4-fs (loop4): mount failed syz-executor.2 D27480 5844 8572 0x00080004 EXT4-fs error (device loop1): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop1): get root inode failed Call Trace: EXT4-fs (loop1): mount failed context_switch kernel/sched/core.c:2853 [inline] __schedule+0x80c/0x1fc0 kernel/sched/core.c:3501 schedule+0x7f/0x1b0 kernel/sched/core.c:3545 EXT4-fs error (device loop0): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated schedule_timeout+0x70e/0xd20 kernel/time/timer.c:1777 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x3fb/0x5d0 kernel/sched/completion.c:115 EXT4-fs (loop0): get root inode failed EXT4-fs (loop0): mount failed wait_for_completion+0x18/0x20 kernel/sched/completion.c:136 kthread_stop+0xc9/0x550 kernel/kthread.c:548 ext4_fill_super+0x71af/0xaf00 fs/ext4/super.c:4497 EXT4-fs error (device loop5): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs error (device loop3): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs error (device loop4): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop3): get root inode failed EXT4-fs (loop5): get root inode failed EXT4-fs (loop4): get root inode failed EXT4-fs (loop5): mount failed EXT4-fs (loop3): mount failed EXT4-fs (loop4): mount failed EXT4-fs error (device loop1): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop1): get root inode failed mount_bdev+0x26f/0x330 fs/super.c:1174 EXT4-fs (loop1): mount failed ext4_mount+0x10/0x20 fs/ext4/super.c:5839 mount_fs+0x7f/0x2a9 fs/super.c:1277 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2542 [inline] do_mount+0x376/0x2710 fs/namespace.c:2872 EXT4-fs error (device loop0): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop0): get root inode failed EXT4-fs (loop0): mount failed ksys_mount+0xb1/0xd0 fs/namespace.c:3088 __do_sys_mount fs/namespace.c:3102 [inline] __se_sys_mount fs/namespace.c:3099 [inline] __x64_sys_mount+0xb9/0x150 fs/namespace.c:3099 do_syscall_64+0xda/0x540 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f49519f3f6a Code: Bad RIP value. RSP: 002b:00007f4951146fa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f49519f3f6a EXT4-fs error (device loop4): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f4951147000 EXT4-fs (loop4): get root inode failed RBP: 00007f4951147040 R08: 00007f4951147040 R09: 0000000020000000 EXT4-fs (loop4): mount failed R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f4951147000 R15: 0000000020000340 Showing all locks held in the system: EXT4-fs error (device loop3): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs error (device loop5): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs error (device loop1): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop5): get root inode failed EXT4-fs (loop3): get root inode failed 1 lock held by khungtaskd/1509: EXT4-fs (loop3): mount failed #0: 00000000b6b11035 (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4461 EXT4-fs (loop1): get root inode failed 1 lock held by in:imklog/7886: EXT4-fs error (device loop0): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop5): mount failed #0: 0000000000cdfad3 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xa7/0xd0 fs/file.c:766 EXT4-fs (loop1): mount failed EXT4-fs (loop0): get root inode failed EXT4-fs (loop0): mount failed 1 lock held by syz-executor.2/5844: #0: 0000000064b86184 (&type->s_umount_key#25/1){+.+.}, at: alloc_super fs/super.c:223 [inline] #0: 0000000064b86184 (&type->s_umount_key#25/1){+.+.}, at: sget_userns+0x1a1/0xb60 fs/super.c:516 EXT4-fs error (device loop4): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop4): get root inode failed 1 lock held by systemd-udevd/6155: EXT4-fs (loop4): mount failed 1 lock held by syz-executor241/11351: #0: 00000000aaada9eb (&lo->lo_ctl_mutex/1){+.+.}, at: lo_ioctl+0x86/0x1a80 drivers/block/loop.c:1405 1 lock held by syz-executor241/11370: #0: 000000002f6611bd (&lo->lo_ctl_mutex/1){+.+.}, at: lo_ioctl+0x86/0x1a80 drivers/block/loop.c:1405 1 lock held by syz-executor241/11381: EXT4-fs error (device loop3): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated #0: 00000000128d37e7 (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x25/0x470 fs/block_dev.c:1814 EXT4-fs (loop3): get root inode failed 4 locks held by syz-executor241/11408: EXT4-fs (loop3): mount failed EXT4-fs error (device loop4): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop4): get root inode failed EXT4-fs (loop4): mount failed #0: EXT4-fs error (device loop0): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated 00000000b2639435 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1812 [inline] 00000000b2639435 (&rq->lock){-.-.}, at: __schedule+0x1f6/0x1fc0 kernel/sched/core.c:3439 EXT4-fs (loop0): get root inode failed #1: 00000000b6b11035 (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:413 [inline] #1: 00000000b6b11035 (rcu_read_lock){....}, at: update_curr+0x2d1/0x8b0 kernel/sched/fair.c:831 EXT4-fs error (device loop5): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated #2: EXT4-fs error (device loop1): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop0): mount failed 000000003e00b823 EXT4-fs (loop5): get root inode failed ( EXT4-fs (loop5): mount failed &sig->wait_chldexit){....}, at: __wake_up_common_lock+0xba/0x180 kernel/sched/wait.c:118 EXT4-fs (loop1): get root inode failed EXT4-fs (loop1): mount failed #3: 0000000054d56fd5 (&(&sig->stats_lock)->seqcount){....}, at: release_task kernel/exit.c:184 [inline] #3: 0000000054d56fd5 (&(&sig->stats_lock)->seqcount){....}, at: exit_notify kernel/exit.c:735 [inline] #3: 0000000054d56fd5 (&(&sig->stats_lock)->seqcount){....}, at: do_exit+0x173a/0x2aa0 kernel/exit.c:885 EXT4-fs error (device loop3): ext4_iget:4777: inode #2: comm syz-executor241: root inode unallocated EXT4-fs (loop3): get root inode failed 2 locks held by syz-executor241/11416: EXT4-fs (loop3): mount failed 1 lock held by syz-executor241/11425: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1509 Comm: khungtaskd Not tainted 4.18.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x15a/0x20d lib/dump_stack.c:113 nmi_cpu_backtrace.cold.0+0x13/0xb6 lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0xf6/0x11a lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline] watchdog+0x512/0x940 kernel/hung_task.c:252 kthread+0x316/0x3d0 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54