New subject: Subject: Re: [PATCH 1/1] iommu/vt-d: Skip TE disabling on quirky gfx dedicated iommu

22 Jul 2020


      Hi Jun,
On 7/22/20 10:26 AM, Miao, Jun wrote:
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Kernel panic - not syncing: DMAR hardware is malfunctioning
CPU: 0 PID: 347 Comm: rtcwake Not tainted 5.4.0-yocto-standard #124
Hardware name: Intel Corporation Ice Lake Client Platform/IceLake U DDR4
SODIMM PD RVP TLC, BIOS ICLSFWR1.R00.3162.A00.1904162000 04/16/2019
Call Trace:
   dump_stack+0x59/0x75
   panic+0xff/0x2d4
   iommu_disable_translation+0x88/0x90
   iommu_suspend+0x12f/0x1b0
   syscore_suspend+0x6c/0x220
   suspend_devices_and_enter+0x313/0x840
   pm_suspend+0x30d/0x390
   state_store+0x82/0xf0
   kobj_attr_store+0x12/0x20
   sysfs_kf_write+0x3c/0x50
   kernfs_fop_write+0x11d/0x190
   __vfs_write+0x1b/0x40
   vfs_write+0xc6/0x1d0
   ksys_write+0x5e/0xe0
   __x64_sys_write+0x1a/0x20
   do_syscall_64+0x4d/0x150
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f97b8080113
Code: 8b 15 81 bd 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00
64 8b 04 25 18 00 00 00 85 c0 75 14 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff
77 55 c3 0f 1f 40 00 48 83 ec 28 48 89 54 24 18
RSP: 002b:00007ffcfa6f48b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f97b8080113
RDX: 0000000000000004 RSI: 000055e7db03b700 RDI: 0000000000000004
RBP: 000055e7db03b700 R08: 000055e7db03b700 R09: 0000000000000004
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000004
R13: 000055e7db039380 R14: 0000000000000004 R15: 00007f97b814d700
Kernel Offset: 0x38a00000 from 0xffffffff81000000 (relocation range:
0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: DMAR hardware is malfunctioning ]---
Do you mean that system hangs in iommu_disable_translation() without 
this fix.
...
[S3 successfully with the patch]
And, this failure disappeared after you applied this fix?
Best regards,
baolu

Re: Subject: Re: [PATCH 1/1] iommu/vt-d: Skip TE disabling on quirky gfx dedicated iommu