bisecting fixing commit since e1f7d50ae3a3ec342e87a9b1ce6787bfb8b3c08b building syzkaller on be5c2c81971442d623dd1b265dabf4644ceeb35b testing commit e1f7d50ae3a3ec342e87a9b1ce6787bfb8b3c08b with gcc (GCC) 8.1.0 kernel signature: 1fa55ac3a2b9249c20c5d79864ed4868b254b6e8c91d7dbbffd0f486203697f1 run #0: crashed: BUG: corrupted list in p9_read_work run #1: crashed: BUG: corrupted list in p9_read_work run #2: crashed: BUG: corrupted list in p9_read_work run #3: crashed: BUG: corrupted list in p9_read_work run #4: crashed: BUG: corrupted list in p9_read_work run #5: crashed: BUG: corrupted list in p9_read_work run #6: crashed: BUG: corrupted list in p9_read_work run #7: crashed: BUG: corrupted list in p9_read_work run #8: crashed: BUG: corrupted list in p9_read_work run #9: crashed: no output from test machine testing current HEAD 98db2bf27b9ed2d5ed0b6c9c8a4bfcb127a19796 testing commit 98db2bf27b9ed2d5ed0b6c9c8a4bfcb127a19796 with gcc (GCC) 8.1.0 kernel signature: e90361e33cf4fe64c24836e8c18b6f37ef8a52931cdb7fc100a879d6c3669af7 all runs: crashed: BUG: corrupted list in p9_read_work revisions tested: 2, total time: 32m32.467075481s (build: 19m8.885415487s, test: 12m39.42603677s) the crash still happens on HEAD commit msg: Linux 4.14.171 crash: BUG: corrupted list in p9_read_work list_del corruption, ffff888078be1468->next is LIST_POISON1 (dead000000000100) ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:47! invalid opcode: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 1 PID: 7014 Comm: kworker/1:3 Not tainted 4.14.171-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events p9_read_work task: ffff88807c4fe1c0 task.stack: ffff8880a6618000 RIP: 0010:__list_del_entry_valid.cold.1+0x26/0x58 lib/list_debug.c:45 RSP: 0018:ffff8880a661fc68 EFLAGS: 00010286 RAX: 000000000000004e RBX: ffff888078be1468 RCX: 0000000000000000 RDX: 000000000000004e RSI: ffffffff86cc2b20 RDI: ffffed1014cc3f84 RBP: ffff8880a661fc80 R08: ffff88807c4feab0 R09: 0000000000000000 R10: 0000000000000000 R11: dffffc0000000000 R12: dead000000000200 R13: dead000000000100 R14: ffff888078be1440 R15: ffff888094f472f8 FS: 0000000000000000(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000007fffffff CR3: 000000008b50b000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry include/linux/list.h:117 [inline] list_del include/linux/list.h:125 [inline] p9_read_work+0x7b0/0x10a0 net/9p/trans_fd.c:386 process_one_work+0x79e/0x16c0 kernel/workqueue.c:2114 worker_thread+0xcc/0xee0 kernel/workqueue.c:2248 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: ee 44 fe 0f 0b 4c 89 e2 48 89 de 48 c7 c7 e0 c5 03 87 e8 03 ee 44 fe 0f 0b 4c 89 ea 48 89 de 48 c7 c7 80 c5 03 87 e8 ef ed 44 fe <0f> 0b 48 89 de 48 c7 c7 a0 c6 03 87 e8 de ed 44 fe 0f 0b 48 89 RIP: __list_del_entry_valid.cold.1+0x26/0x58 lib/list_debug.c:45 RSP: ffff8880a661fc68 ---[ end trace 1b52f2f418ffac89 ]---