bisecting fixing commit since dafd634415a7f9892a6fcc99c540fe567ab42c92 building syzkaller on 2f661ec405cb3975128e9851c7a5979d92d001f1 testing commit dafd634415a7f9892a6fcc99c540fe567ab42c92 with gcc (GCC) 8.4.1 20210217 kernel signature: a87c31af49afe0b34038a75c44ccbb6b04f1bb05d64d48e99a5451e07ea52837 all runs: crashed: WARNING in check_for_bios_corruption testing current HEAD 3c8c23092588a23bf1856a64f58c37f477a413be testing commit 3c8c23092588a23bf1856a64f58c37f477a413be with gcc (GCC) 8.4.1 20210217 kernel signature: 70e68d3198d99509a6574517968307a58d19d9eb4dca07136a0bb9e764fef9dd all runs: crashed: WARNING in check_for_bios_corruption revisions tested: 2, total time: 23m11.032861435s (build: 15m58.405460687s, test: 6m30.784372013s) the crash still happens on HEAD commit msg: Linux 4.19.190 crash: WARNING in check_for_bios_corruption Corrupted low memory at 00000000f2b853de (2900 phys) = 000000e8 ------------[ cut here ]------------ Memory corruption detected in low memory WARNING: CPU: 1 PID: 6558 at arch/x86/kernel/check.c:157 check_for_bios_corruption arch/x86/kernel/check.c:157 [inline] WARNING: CPU: 1 PID: 6558 at arch/x86/kernel/check.c:157 check_for_bios_corruption+0x10c/0x1d0 arch/x86/kernel/check.c:135 Modules linked in: CPU: 1 PID: 6558 Comm: kworker/1:4 Not tainted 4.19.190-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events check_corruption RIP: 0010:check_for_bios_corruption arch/x86/kernel/check.c:157 [inline] RIP: 0010:check_for_bios_corruption+0x10c/0x1d0 arch/x86/kernel/check.c:135 Code: c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 c3 80 3d b8 be a4 07 00 75 e7 48 c7 c7 e0 58 e7 86 c6 05 a8 be a4 07 01 e8 f5 7d 48 05 <0f> 0b eb d0 48 89 df 89 55 d0 e8 e5 36 66 00 8b 55 d0 49 b8 00 00 RSP: 0018:ffff8881e7447d08 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff888000010000 RCX: 0000000000000000 RDX: 0000000000000004 RSI: ffffffff871f5f60 RDI: ffffffff89c8e6e0 RBP: ffff8881e7447d40 R08: ffffed103ed25079 R09: ffffed103ed25078 R10: ffffed103ed25078 R11: ffff8881f69283c7 R12: ffff888000010000 R13: dffffc0000000000 R14: 0000000000000001 R15: ffffffff890b00a0 FS: 0000000000000000(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001312728 CR3: 000000000806d002 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: check_corruption+0xd/0x70 arch/x86/kernel/check.c:165 process_one_work+0x830/0x1670 kernel/workqueue.c:2152 worker_thread+0x85/0xb60 kernel/workqueue.c:2295 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 irq event stamp: 350996 hardirqs last enabled at (350995): [] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] hardirqs last enabled at (350995): [] _raw_spin_unlock_irq+0x27/0x80 kernel/locking/spinlock.c:192 hardirqs last disabled at (350996): [] trace_hardirqs_off_thunk+0x1a/0x1c softirqs last enabled at (350934): [] srcu_invoke_callbacks+0x221/0x3e0 kernel/rcu/srcutree.c:1199 softirqs last disabled at (350930): [] spin_unlock_irq include/linux/spinlock.h:379 [inline] softirqs last disabled at (350930): [] srcu_invoke_callbacks+0x1cc/0x3e0 kernel/rcu/srcutree.c:1194 ---[ end trace d57cb11741a8eb28 ]---