kernel NULL pointer dereference

[dry]

They _may_ /could be due to vboxvideo driver.

Started with couple/few error traces in the log about drm, then ended up with crashed desktop session

[64984.348822] [drm:drm_crtc_helper_set_config [drm_kms_helper]] *ERROR* failed to set mode on [CRTC:31:crtc-0]
[64984.356580] [drm:drm_crtc_helper_set_config [drm_kms_helper]] *ERROR* failed to set mode on [CRTC:37:crtc-1]

The BUG trace later, after desktop GUI and/or X session crashed froze:

[131602.799054] [drm:drm_crtc_helper_set_config [drm_kms_helper]] *ERROR* failed to set mode on [CRTC:31:crtc-0]
[131602.801233] [drm:drm_crtc_helper_set_config [drm_kms_helper]] *ERROR* failed to set mode on [CRTC:37:crtc-1]
[131602.829342] BUG: kernel NULL pointer dereference, address: 0000000000000080
[131602.829345] #PF: supervisor read access in kernel mode
[131602.829346] #PF: error_code(0x0000) - not-present page
[131602.829347] PGD 0 P4D 0
[131602.829349] Oops: 0000 [#1] SMP PTI
[131602.829350] CPU: 3 PID: 2314 Comm: Xorg Tainted: G           OE     5.2.7-100.fc29.x86_64 #1
[131602.829351] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[131602.829355] RIP: 0010:vbox_crtc_mode_set+0x36a/0x410 [vboxvideo]
[131602.829356] Code: 85 98 fd ff ff 48 8b 40 10 c6 40 50 00 e9 58 fd ff ff c6 83 48 08 00 00 01 49 8b 82 80 00 00 00 83 f7 01 48 8b 80 a8 00 00 00 <8b> 80 80 00 00 00 89 83 40 08 00 00 49 8b 82 80 00 00 00 48 8b 80
[131602.829357] RSP: 0018:ffffa78bc1a2b8e0 EFLAGS: 00010246
[131602.829359] RAX: 0000000000000000 RBX: ffff8a1590560000 RCX: ffff8a15917b02e8
[131602.829359] RDX: 0000000000000000 RSI: ffff8a15917b0000 RDI: 0000000000000000
[131602.829360] RBP: 0000000000000000 R08: ffff8a15917b02d8 R09: ffffffffc05c0b7d
[131602.829361] R10: ffff8a15917b3000 R11: 0000000000000001 R12: ffff8a1596218800
[131602.829362] R13: ffff8a15917b3010 R14: ffff8a151719fe00 R15: 0000000000000000
[131602.829363] FS:  00007f41555aaac0(0000) GS:ffff8a1597b80000(0000) knlGS:0000000000000000
[131602.829364] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[131602.829365] CR2: 0000000000000080 CR3: 00000001cbc5c002 CR4: 00000000000606e0
[131602.829367] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[131602.829368] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[131602.829369] Call Trace:
[131602.829376]  drm_crtc_helper_set_mode+0x361/0x530 [drm_kms_helper]
[131602.829383]  drm_crtc_helper_set_config+0x53d/0x9c0 [drm_kms_helper]
[131602.829395]  __drm_mode_set_config_internal+0xa2/0x170 [drm]
[131602.829403]  drm_mode_setcrtc+0x4e6/0x6d0 [drm]
[131602.829407]  ? unix_stream_recvmsg+0x53/0x70
[131602.829408]  ? unix_set_peek_off+0x50/0x50
[131602.829416]  ? drm_mode_getcrtc+0x180/0x180 [drm]
[131602.829422]  drm_ioctl_kernel+0xac/0xf0 [drm]
[131602.829429]  drm_ioctl+0x201/0x3a0 [drm]
[131602.829437]  ? drm_mode_getcrtc+0x180/0x180 [drm]
[131602.829440]  ? selinux_file_ioctl+0x17f/0x220
[131602.829442]  do_vfs_ioctl+0xa4/0x630
[131602.829449]  ? security_file_ioctl+0x32/0x50
[131602.829451]  ksys_ioctl+0x60/0x90
[131602.829453]  __x64_sys_ioctl+0x16/0x20
[131602.829455]  do_syscall_64+0x5f/0x1a0
[131602.829457]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[131602.829458] RIP: 0033:0x7f4155adb0fb
[131602.829460] Code: 0f 1e fa 48 8b 05 8d bd 0c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 5d bd 0c 00 f7 d8 64 89 01 48
[131602.829461] RSP: 002b:00007ffcd7489ec8 EFLAGS: 00003246 ORIG_RAX: 0000000000000010
[131602.829462] RAX: ffffffffffffffda RBX: 00007ffcd7489f00 RCX: 00007f4155adb0fb
[131602.829463] RDX: 00007ffcd7489f00 RSI: 00000000c06864a2 RDI: 0000000000000010
[131602.829464] RBP: 00007ffcd7489f00 R08: 0000000000000000 R09: 0000564460cc1970
[131602.829465] R10: 00007ffcd7489fc0 R11: 0000000000003246 R12: 00000000c06864a2
[131602.829465] R13: 0000000000000010 R14: 0000564460b93e40 R15: 00007ffcd7489fc0
[131602.829467] Modules linked in: fuse vboxsf(OE) nf_nat_tftp nf_conntrack_tftp xt_CT ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat iptable_mangle iptable_raw iptable_security nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c ip_set nfnetlink ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter ip_tables overlay squashfs zstd_decompress sunrpc loop crct10dif_pclmul crc32_pclmul ghash_clmulni_intel intel_rapl_perf joydev i2c_piix4 vboxvideo(OE) drm_kms_helper ttm drm mptsas scsi_transport_sas crc32c_intel serio_raw mptscsih ata_generic mptbase e1000 vboxguest(OE) pata_acpi video
[131602.829485] CR2: 0000000000000080
[131602.829486] ---[ end trace 13adb492ca13c508 ]---
[131602.829489] RIP: 0010:vbox_crtc_mode_set+0x36a/0x410 [vboxvideo]
[131602.829490] Code: 85 98 fd ff ff 48 8b 40 10 c6 40 50 00 e9 58 fd ff ff c6 83 48 08 00 00 01 49 8b 82 80 00 00 00 83 f7 01 48 8b 80 a8 00 00 00 <8b> 80 80 00 00 00 89 83 40 08 00 00 49 8b 82 80 00 00 00 48 8b 80
[131602.829491] RSP: 0018:ffffa78bc1a2b8e0 EFLAGS: 00010246
[131602.829492] RAX: 0000000000000000 RBX: ffff8a1590560000 RCX: ffff8a15917b02e8
[131602.829492] RDX: 0000000000000000 RSI: ffff8a15917b0000 RDI: 0000000000000000
[131602.829493] RBP: 0000000000000000 R08: ffff8a15917b02d8 R09: ffffffffc05c0b7d
[131602.829494] R10: ffff8a15917b3000 R11: 0000000000000001 R12: ffff8a1596218800
[131602.829495] R13: ffff8a15917b3010 R14: ffff8a151719fe00 R15: 0000000000000000
[131602.829496] FS:  00007f41555aaac0(0000) GS:ffff8a1597b80000(0000) knlGS:0000000000000000
[131602.829497] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[131602.829498] CR2: 0000000000000080 CR3: 00000001cbc5c002 CR4: 00000000000606e0
[131602.829498] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[131602.829499] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

[dry]

Could not restart graphical user systemd runlevel, had to reboot.

Upon reboot, got immediately the same crash /error, and dark screen on my Vbox "desktops". That was unusual. Error in the kernel log is same.

Powered off. Disconnected my second "virtual" monitor, booted. This time was no error. Powered off. Connected my second monitor back, booted. This time started Ok , with two monitors.

[Frank Batschulat (Oracle)]

duplicate of bug:

#18443 (closed defect: fixed) Kernel Oops in vboxvideo -> fixed in 6.0.6 https://www.virtualbox.org/ticket/18443

use the test builds from: https://www.virtualbox.org/wiki/Testbuilds

until a new release comes out.