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: 9873 Comm: syz-executor.2 Not tainted 5.8.0-rc2-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:ffffc90001996eb8 EFLAGS: 00010046 RAX: dffffc0000000000 RBX: ffff8880ae735e18 RCX: 0000000000000000 RDX: 1ffff11015ce6bc2 RSI: ffff8880878b0480 RDI: ffff888050d6e4c0 RBP: ffffc90001996f88 R08: 0000000000000001 R09: ffff888050d6ed88 R10: fffffbfff155c591 R11: 0000000000000000 R12: ffff8880ae735e00 R13: ffff888050d6e4c0 R14: ffff8880878b0480 R15: ffff888050d6e8f0 FS: 00007f2518012700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f855f814db8 CR3: 000000009c1a5000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4155 preempt_schedule_irq+0xb0/0x150 kernel/sched/core.c:4413 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:__sanitizer_cov_trace_pc+0x45/0x60 kernel/kcov.c:202 Code: f6 c4 01 74 35 8b 82 04 14 00 00 85 c0 74 2b 8b 82 e0 13 00 00 83 f8 02 75 20 48 8b 8a e8 13 00 00 8b 92 e4 13 00 00 48 8b 01 <48> 83 c0 01 48 39 c2 76 07 48 89 34 c1 48 89 01 c3 66 2e 0f 1f 84 RSP: 0018:ffffc90001997080 EFLAGS: 00000246 RAX: 000000000003ffff RBX: 0000000000000050 RCX: ffffc9000d1e2000 RDX: 0000000000040000 RSI: ffffffff83c5d560 RDI: 0000000000000004 RBP: 000000000000000f R08: 0000000000000001 R09: ffff88821889e6df R10: 0000000000000050 R11: 0000000000000000 R12: ffff88800100964f R13: ffff888001009640 R14: 0000000000000000 R15: 00000000fffceaeb writeb arch/x86/include/asm/io.h:65 [inline] vga16fb_fillrect+0x9c0/0x193b drivers/video/fbdev/vga16fb.c:923 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: 0033:0x45cb19 Code: Bad RIP value. RSP: 002b:00007f2518011c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e5500 RCX: 000000000045cb19 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000006 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002fc R14: 00000000004c587a R15: 00007f25180126d4 Modules linked in: ---[ end trace 2dd8de0c6c9d35ab ]--- 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:ffffc90001996eb8 EFLAGS: 00010046 RAX: dffffc0000000000 RBX: ffff8880ae735e18 RCX: 0000000000000000 RDX: 1ffff11015ce6bc2 RSI: ffff8880878b0480 RDI: ffff888050d6e4c0 RBP: ffffc90001996f88 R08: 0000000000000001 R09: ffff888050d6ed88 R10: fffffbfff155c591 R11: 0000000000000000 R12: ffff8880ae735e00 R13: ffff888050d6e4c0 R14: ffff8880878b0480 R15: ffff888050d6e8f0 FS: 00007f2518012700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f855f814db8 CR3: 000000009c1a5000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400