4.14-rc2 kernel NULL pointer dereference BUG : set_best_encoder+0x1b/0xa0

[Jongman Heo]

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Hi,


I'm using VMWare Workstation 12 Pro, Windows7 host, Linux guest (Fedora 27).

With current linus git (HEAD 770b782f55 - Merge tag 'acpi-4.14-rc3' ...), I hit following kernel BUG.
It's not 100% reproduced, so sometimes I can see gnome login manager, sometimes I can't.

git bisect may not be an option, I have a boot problem around 4.14-rc1, which seems to be recently improved (not completely fixed :( ).


=======================================================================================

[   45.086081] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[   45.086091] IP: set_best_encoder+0x1b/0xa0 [drm_kms_helper]
[   45.086092] PGD b527c067 P4D b527c067 PUD 35808067 PMD 0 
[   45.086095] Oops: 0000 [#1] SMP
[   45.086097] Modules linked in: xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack libcrc32c tun bridge stp llc ebtable_filter ebtables ip6table_filter ip6_tables vmw_vsock_vmci_transport vsock snd_seq_midi snd_seq_midi_event coretemp kvm_intel kvm snd_ens1371 irqbypass gameport snd_ac97_codec ac97_bus crct10dif_pclmul crc32_pclmul snd_seq snd_pcm ghash_clmulni_intel snd_rawmidi intel_rapl_perf snd_timer vmw_balloon joydev snd_seq_device snd soundcore shpchp nfit i2c_piix4 vmw_vmci vmwgfx drm_kms_helper mptspi crc32c_intel scsi_transport_spi ttm serio_raw mptscsih drm pcnet32 mptbase ata_generic mii pata_acpi
[   45.086121] CPU: 3 PID: 884 Comm: Xorg Not tainted 4.14.0-rc2+ #108
[   45.086122] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015
[   45.086123] task: ffff91f86b8da640 task.stack: ffffb659c209c000
[   45.086127] RIP: 0010:set_best_encoder+0x1b/0xa0 [drm_kms_helper]
[   45.086127] RSP: 0018:ffffb659c209fad0 EFLAGS: 00010246
[   45.086128] RAX: 0000000000000000 RBX: ffff91f87bae7680 RCX: ffff91f7f6bb44b0
[   45.086129] RDX: ffff91f7f6bb44b0 RSI: ffff91f7f5cb7780 RDI: ffff91f87bae7680
[   45.086130] RBP: ffff91f7f6bb4520 R08: ffff91f87af20db0 R09: ffff91f7f6bb44c8
[   45.086130] R10: 0000000000000000 R11: 0000000000000040 R12: ffff91f7f5cb7780
[   45.086131] R13: 0000000000000000 R14: ffff91f7f5cb70c0 R15: ffffffffc02b7140
[   45.086132] FS:  00007f41904cea80(0000) GS:ffff91f87fcc0000(0000) knlGS:0000000000000000
[   45.086133] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   45.086134] CR2: 0000000000000008 CR3: 00000000b8fe9004 CR4: 00000000001606e0
[   45.086167] Call Trace:
[   45.086173]  drm_atomic_helper_check_modeset+0x62e/0xa80 [drm_kms_helper]
[   45.086177]  drm_atomic_helper_check+0x14/0x60 [drm_kms_helper]
[   45.086187]  drm_atomic_check_only+0x37c/0x540 [drm]
[   45.086195]  drm_atomic_commit+0x13/0x50 [drm]
[   45.086199]  drm_atomic_helper_set_config+0x61/0x90 [drm_kms_helper]
[   45.086201]  ? __kmalloc+0x171/0x200
[   45.086208]  __drm_mode_set_config_internal+0x61/0x110 [drm]
[   45.086214]  drm_mode_setcrtc+0x3ff/0x590 [drm]
[   45.086220]  ? drm_mode_getcrtc+0x160/0x160 [drm]
[   45.086239]  drm_ioctl_kernel+0x59/0xb0 [drm]
[   45.086267]  drm_ioctl+0x2cb/0x380 [drm]
[   45.086274]  ? drm_mode_getcrtc+0x160/0x160 [drm]
[   45.086290]  ? add_wait_queue+0x3a/0x70
[   45.086295]  vmw_generic_ioctl+0x18e/0x2c0 [vmwgfx]
[   45.086300]  ? drm_getstats+0x20/0x20 [drm]
[   45.086303]  do_vfs_ioctl+0xa1/0x610
[   45.086305]  SyS_ioctl+0x74/0x80
[   45.086307]  entry_SYSCALL_64_fastpath+0x1a/0xa5
[   45.086309] RIP: 0033:0x7f418d79f317
[   45.086309] RSP: 002b:00007ffcd51d2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[   45.086311] RAX: ffffffffffffffda RBX: 00007f418da6fc20 RCX: 00007f418d79f317
[   45.086311] RDX: 00007ffcd51d2070 RSI: 00000000c06864a2 RDI: 000000000000000c
[   45.086312] RBP: 00007f418da6fc78 R08: 0000000000000000 R09: 00007ffcd51d213c
[   45.086313] R10: 00007ffcd51d2140 R11: 0000000000000246 R12: 0000000000000020
[   45.086313] R13: 0000000000000010 R14: 00007f418da6fc78 R15: 0000000000000000
[   45.086314] Code: 0f 1f 44 00 00 48 8b 07 48 8b 00 48 89 06 c3 90 0f 1f 44 00 00 48 8b 4e 10 48 85 c9 74 49 48 8b 06 48 39 d1 48 8b 80 d8 03 00 00 <48> 8b 40 08 74 05 48 85 c0 74 6e 48 85 c0 74 2c 44 8b 80 90 00 
[   45.086333] RIP: set_best_encoder+0x1b/0xa0 [drm_kms_helper] RSP: ffffb659c209fad0
[   45.086334] CR2: 0000000000000008
[   45.086364] ---[ end trace 039f0e635b47cbec ]---



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í ì ëÂ(Heo Jongman)

PrincipalÂEngineer
STB S/W Lab 
Visual DisplayÂBusiness
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Mobile : 82 - 10 - 7260 - 9532
SAMSUNG ELECTRONICS CO., LTD.
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