general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 25092 Comm: syz-executor.1 Not tainted 5.8.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__switch_to_asm+0x0/0x40 arch/x86/entry/entry_64.S:228 Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 RSP: 0018:ffffc90015f1eeb8 EFLAGS: 00010046 RAX: dffffc0000000000 RBX: ffff8880ae735e18 RCX: 0000000000000000 RDX: 1ffff11015ce6bc2 RSI: ffff888053d5e3c0 RDI: ffff88805790e140 RBP: ffffc90015f1ef88 R08: 0000000000000001 R09: ffff88805790ea08 R10: fffffbfff155cb09 R11: 0000000000000000 R12: ffff8880ae735e00 R13: ffff88805790e140 R14: ffff888053d5e3c0 R15: ffff88805790e570 FS: 00007fefad0b8700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000740694 CR3: 0000000053cdd000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:4436 idtentry_exit_cond_resched arch/x86/entry/common.c:621 [inline] idtentry_exit_cond_rcu+0xc0/0xf0 arch/x86/entry/common.c:668 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:596 RIP: 0010:write_comp_data+0x2f/0x80 kernel/kcov.c:218 Code: 05 56 4c 8e 7e 65 48 8b 34 25 00 ff 01 00 a9 00 01 ff 00 74 0f f6 c4 01 74 59 8b 86 04 14 00 00 85 c0 74 4f 8b 86 e0 13 00 00 <83> f8 03 75 44 48 8b 86 e8 13 00 00 8b b6 e4 13 00 00 4c 8b 00 48 RSP: 0018:ffffc90015f1f080 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 0000000000000050 RCX: ffffffff83c645e4 RDX: 0000000000000004 RSI: ffff88805790e140 RDI: 0000000000000004 RBP: 0000000000000004 R08: 0000000000000001 R09: ffff8882188766df R10: 0000000000000050 R11: 0000000000000000 R12: ffff888001007c04 R13: ffff888001007c00 R14: 0000000000000000 R15: 00000000fffceb3f vga16fb_fillrect+0x9d4/0x193b drivers/video/fbdev/vga16fb.c:922 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x1d5/0x230 drivers/video/fbdev/core/fbcon.c:1381 fbcon_switch+0xb6e/0x16c0 drivers/video/fbdev/core/fbcon.c:2363 redraw_screen+0x2ae/0x770 drivers/tty/vt/vt.c:1015 fbcon_modechanged+0x575/0x710 drivers/video/fbdev/core/fbcon.c:3001 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 fbcon_switch+0x52c/0x16c0 drivers/video/fbdev/core/fbcon.c:2296 redraw_screen+0x2ae/0x770 drivers/tty/vt/vt.c:1015 fbcon_modechanged+0x575/0x710 drivers/video/fbdev/core/fbcon.c:3001 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x33f/0x6c0 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:753 __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl fs/ioctl.c:760 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb29 Code: Bad RIP value. RSP: 002b:00007fefad0b7c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e55a0 RCX: 000000000045cb29 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 000000000000000a RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002fd R14: 00000000004c58a5 R15: 00007fefad0b86d4 Modules linked in: ---[ end trace c2b129c26ed52801 ]--- RIP: 0010:__switch_to_asm+0x0/0x40 arch/x86/entry/entry_64.S:228 Code: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 RSP: 0018:ffffc90015f1eeb8 EFLAGS: 00010046 RAX: dffffc0000000000 RBX: ffff8880ae735e18 RCX: 0000000000000000 RDX: 1ffff11015ce6bc2 RSI: ffff888053d5e3c0 RDI: ffff88805790e140 RBP: ffffc90015f1ef88 R08: 0000000000000001 R09: ffff88805790ea08 R10: fffffbfff155cb09 R11: 0000000000000000 R12: ffff8880ae735e00 R13: ffff88805790e140 R14: ffff888053d5e3c0 R15: ffff88805790e570 FS: 00007fefad0b8700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000740694 CR3: 0000000053cdd000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400