Re: [PATCH v9 00/18] Add VT-d Posted-Interrupts support - including prerequisite series

[Paolo Bonzini <pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On 28/09/2015 12:14, Wu, Feng wrote:
> Thanks a lot for creating branch for vt-d pi. However, I cannot launch guests
> with this tree. I encountered the following kernel dump, and I find that the
> problematic commit is " 2260b1cde0b5472ab70ad0764b10095372e41913 "
> 
>     KVM: x86: put vcpu_create under kvm->srcu critical section
> 
>     This is needed in case vcpu_create wants to access the memslots array.
>     Fixes this lockdep splat:
> 
> After removing this commit from the tree, my VT-d patch-set works fine.

Great, thanks.  The above commit had already been reverted.

I'm sorting out the kbuild reports, and then will merge VT-d PI.

Paolo

> 
> Kernel dump:
> [  221.978182] BUG: unable to handle kernel NULL pointer dereference at           (null)
> [  221.986085] IP: [<ffffffffc0368ab0>] kvm_arch_vcpu_create+0x30/0x90 [kvm]
> [  221.993102] PGD 0
> [  221.995148] Oops: 0000 [#1] SMP
> [  221.998440] Modules linked in: bnep rfcomm bluetooth ax88179_178a usbnet intel_rapl mii snd_hda_codec_hdmi iosf_mbi x86_pkg_temp_thermal nouveau intel_powerclamp snd_hda_intel snd_hda_codec coretemp kvm_intel snd_hda_core kvm snd_hwdep snd_pcm crct10dif_pclmul crc32_pclmul snd_seq_midi ghash_clmulni_intel mxm_wmi snd_seq_midi_event snd_rawmidi video snd_seq ttm aesni_intel aes_x86_64 lrw gf128mul drm_kms_helper snd_seq_device binfmt_misc snd_timer glue_helper ablk_helper drm cryptd fb_sys_fops snd syscopyarea sysfillrect sb_edac soundcore sysimgblt mei_me parport_pc edac_core ppdev mei shpchp lp lpc_ich mac_hid parport acpi_power_meter wmi ixgbe igb i2c_algo_bit hid_generic usbhid ptp ahci hid libahci pps_core mdio
> [  222.063533] CPU: 4 PID: 3384 Comm: qemu-system-x86 Not tainted 4.3.0-rc1+ #6
> [  222.070612] Hardware name: Intel Corp. GRANGEVILLE/GRANTLEY, BIOS GNVDCRB1.86B.0020.V07.1409241147 09/24/2014
> [  222.080764] task: ffff88006e7c8000 ti: ffff8800714a8000 task.ti: ffff8800714a8000
> [  222.088283] RIP: 0010:[<ffffffffc0368ab0>]  [<ffffffffc0368ab0>] kvm_arch_vcpu_create+0x30/0x90 [kvm]
> [  222.097680] RSP: 0018:ffff8800714abde0  EFLAGS: 00010246
> [  222.103153] RAX: 0000000000000000 RBX: ffff88016f28c000 RCX: 0000000000000000
> [  222.110407] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88016f28c000
> [  222.117659] RBP: ffff8800714abdf8 R08: 0000000000000001 R09: 0000000000000040
> [  222.124824] R10: ffff880077e86438 R11: ffff880163e06880 R12: ffff88016f28c000
> [  222.132150] R13: 0000000000000000 R14: 000000000000ae41 R15: 0000000000000000
> [  222.139405] FS:  00007f43fd7ec700(0000) GS:ffff880178700000(0000) knlGS:0000000000000000
> [  222.147629] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [  222.153471] CR2: 0000000000000000 CR3: 000000017074b000 CR4: 00000000003426e0
> [  222.160726] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [  222.167979] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [  222.175231] Stack:
> [  222.177277]  0000000000000000 ffff88016f28c000 0000000000000000 ffff8800714abea0
> [  222.184870]  ffffffffc0355b17 0000000000000008 ffff8800714abe28 ffffffff810aba32
> [  222.192444]  ffff880178816e40 ffff8800714abe40 ffffffff810a4f44 ffff880178816e40
> [  222.200017] Call Trace:
> [  222.202522]  [<ffffffffc0355b17>] kvm_vm_ioctl+0x277/0x6e0 [kvm]
> [  222.208633]  [<ffffffff810aba32>] ? put_prev_task_fair+0x22/0x40
> [  222.214741]  [<ffffffff810a4f44>] ? pick_next_task_idle+0x14/0x30
> [  222.220942]  [<ffffffff811fb53a>] do_vfs_ioctl+0x2ba/0x490
> [  222.226523]  [<ffffffff8106274a>] ? __do_page_fault+0x1ba/0x410
> [  222.232546]  [<ffffffff811fb789>] SyS_ioctl+0x79/0x90
> [  222.237684]  [<ffffffff81003ba5>] ? syscall_return_slowpath+0x55/0x150
> [  222.244323]  [<ffffffff81791d36>] entry_SYSCALL_64_fastpath+0x16/0x75
> [  222.250869] Code: 55 48 89 e5 41 55 41 54 53 41 89 f5 48 89 fb e8 27 61 cb c0 85 c0 74 13 8b 83 f0 09 00 00 85 c0 74 09 80 3d 53 2e 04 00 00 74 40 <48> 8b 04 25 00 00 00 00 48 8d 78 48 e8 7f c4 d6 c0 41 89 c4 48
> [  222.270790] RIP  [<ffffffffc0368ab0>] kvm_arch_vcpu_create+0x30/0x90 [kvm]
> [  222.277813]  RSP <ffff8800714abde0>
> [  222.281359] CR2: 0000000000000000
> [  222.290421] ---[ end trace 957f5a39692fe6c7 ]---
> root@feng-bdw-de-pi:~/workspace/tools# dmesg > ~/dmesg.log
> root@feng-bdw-de-pi:~/workspace/tools# vim ~/dmesg.log
> [  221.998440] Modules linked in: bnep rfcomm bluetooth ax88179_178a usbnet intel_rapl mii snd_hda_codec_hdmi iosf_mbi x86_pkg_temp_thermal nouveau intel_powerclamp snd_hda_intel snd_hda_codec coretemp kvm_intel snd_hda_core kvm snd_hwdep snd_pcm crct10dif_pclmul crc32_pclmul snd_seq_midi ghash_clmulni_intel mxm_wmi snd_seq_midi_event snd_rawmidi video snd_seq ttm aesni_intel aes_x86_64 lrw gf128mul drm_kms_helper snd_seq_device binfmt_misc snd_timer glue_helper ablk_helper drm cryptd fb_sys_fops snd syscopyarea sysfillrect sb_edac soundcore sysimgblt mei_me parport_pc edac_core ppdev mei shpchp lp lpc_ich mac_hid parport acpi_power_meter wmi ixgbe igb i2c_algo_bit hid_generic usbhid ptp ahci hid libahci pps_core mdio
> [  222.063533] CPU: 4 PID: 3384 Comm: qemu-system-x86 Not tainted 4.3.0-rc1+ #6
> [  222.070612] Hardware name: Intel Corp. GRANGEVILLE/GRANTLEY, BIOS GNVDCRB1.86B.0020.V07.1409241147 09/24/2014
> [  222.080764] task: ffff88006e7c8000 ti: ffff8800714a8000 task.ti: ffff8800714a8000
> [  222.088283] RIP: 0010:[<ffffffffc0368ab0>]  [<ffffffffc0368ab0>] kvm_arch_vcpu_create+0x30/0x90 [kvm]
> [  222.097680] RSP: 0018:ffff8800714abde0  EFLAGS: 00010246
> [  222.103153] RAX: 0000000000000000 RBX: ffff88016f28c000 RCX: 0000000000000000
> [  222.110407] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88016f28c000
> [  222.117659] RBP: ffff8800714abdf8 R08: 0000000000000001 R09: 0000000000000040
> [  222.124824] R10: ffff880077e86438 R11: ffff880163e06880 R12: ffff88016f28c000
> [  222.132150] R13: 0000000000000000 R14: 000000000000ae41 R15: 0000000000000000
> [  222.139405] FS:  00007f43fd7ec700(0000) GS:ffff880178700000(0000) knlGS:0000000000000000
> [  222.147629] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [  222.153471] CR2: 0000000000000000 CR3: 000000017074b000 CR4: 00000000003426e0
> [  222.160726] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [  222.167979] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [  222.175231] Stack:
> [  222.177277]  0000000000000000 ffff88016f28c000 0000000000000000 ffff8800714abea0
> [  222.184870]  ffffffffc0355b17 0000000000000008 ffff8800714abe28 ffffffff810aba32
> [  222.192444]  ffff880178816e40 ffff8800714abe40 ffffffff810a4f44 ffff880178816e40
> [  222.200017] Call Trace:
> [  222.202522]  [<ffffffffc0355b17>] kvm_vm_ioctl+0x277/0x6e0 [kvm]
> [  222.208633]  [<ffffffff810aba32>] ? put_prev_task_fair+0x22/0x40
> [  222.214741]  [<ffffffff810a4f44>] ? pick_next_task_idle+0x14/0x30
> [  222.220942]  [<ffffffff811fb53a>] do_vfs_ioctl+0x2ba/0x490
> [  222.226523]  [<ffffffff8106274a>] ? __do_page_fault+0x1ba/0x410
> [  222.232546]  [<ffffffff811fb789>] SyS_ioctl+0x79/0x90
> [  222.237684]  [<ffffffff81003ba5>] ? syscall_return_slowpath+0x55/0x150
> [  222.244323]  [<ffffffff81791d36>] entry_SYSCALL_64_fastpath+0x16/0x75
> [  222.250869] Code: 55 48 89 e5 41 55 41 54 53 41 89 f5 48 89 fb e8 27 61 cb c0 85 c0 74 13 8b 83 f0 09 00 00 85 c0 74 09 80 3d 53 2e 04 00 00 74 40 <48> 8b 04 25 00 00 00 00 48 8d 78 48 e8 7f c4 d6 c0 41 89 c4 48
> [  222.270790] RIP  [<ffffffffc0368ab0>] kvm_arch_vcpu_create+0x30/0x90 [kvm]
> [  222.277813]  RSP <ffff8800714abde0>
> [  222.281359] CR2: 0000000000000000
> [  222.290421] ---[ end trace 957f5a39692fe6c7 ]---