Re: [PATCH v4 12/15] iommu/vt-d: Cleanup get_valid_domain_for_dev()
From: Alex Williamson
Date: Wed Jul 17 2019 - 23:18:56 EST
On Sat, 25 May 2019 13:41:33 +0800
Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> wrote:
> Previously, get_valid_domain_for_dev() is used to retrieve the
> DMA domain which has been attached to the device or allocate one
> if no domain has been attached yet. As we have delegated the DMA
> domain management to upper layer, this function is used purely to
> allocate a private DMA domain if the default domain doesn't work
> for ths device. Cleanup the code for readability.
>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> ---
> drivers/iommu/intel-iommu.c | 18 ++++++++----------
> include/linux/intel-iommu.h | 1 -
> 2 files changed, 8 insertions(+), 11 deletions(-)
System fails to boot bisected to this commit:
ommit 4ec066c7b1476e0ca66a7acdb575627a5d1a1ee6 (HEAD, refs/bisect/bad)
Author: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Date: Sat May 25 13:41:33 2019 +0800
iommu/vt-d: Cleanup get_valid_domain_for_dev()
[ 6.857697] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[ 6.870723] ehci-pci: EHCI PCI platform driver
[ 6.879666] ehci-pci 0000:00:1a.0: EHCI Host Controller
[ 6.890122] ehci-pci 0000:00:1a.0: new USB bus registered, assigned bus number 1
[ 6.904893] ehci-pci 0000:00:1a.0: debug port 2
[ 6.913961] ehci-pci 0000:00:1a.0: DMAR: Setting identity map [0xbe8d1000 - 0xbe8dffff]
[ 6.929953] ehci-pci 0000:00:1a.0: DMAR: 32bit DMA uses non-identity mapping
[ 6.944033] WARNING: CPU: 0 PID: 1 at drivers/iommu/intel-iommu.c:600 domain_get_iommu+0x55/0x60
[ 6.945017] Modules linked in:
[ 6.945017] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc2+ #37
[ 6.945017] Hardware name: System manufacturer System Product Name/P8H67-M PRO, BIOS 3904 04/27/2013
[ 6.945017] RIP: 0010:domain_get_iommu+0x55/0x60
[ 6.945017] Code: c2 01 eb 0b 48 83 c0 01 8b 34 87 85 f6 75 0b 48 63 c8 48 39 c2 75 ed 31 c0 c3 48 c1 e1 03 48 8b 05 e0 f5 44 01 48 8b 04 08 c3 <0f> 0b 31 c0 c3 31 c9 eb eb 66 90 0f 1f 44 00 00 41 55 40 0f b6 f6
[ 6.945017] RSP: 0018:ffffbd02418bba98 EFLAGS: 00010293
[ 6.945017] RAX: ffffffffffffffff RBX: 0000000000000000 RCX: 0000000000000000
[ 6.945017] RDX: 0000000000001000 RSI: 00000000313ea000 RDI: ffff9ce9f3026e00
[ 6.945017] RBP: ffff9cea144f80b0 R08: 00000000ffffffff R09: ffff9ce9f13ea000
[ 6.945017] R10: 0000000000100000 R11: 0000000000000100 R12: 00000000313ea000
[ 6.945017] R13: ffff9ce9f3026e00 R14: 0000000000001000 R15: 00000000313ea000
[ 6.945017] FS: 0000000000000000(0000) GS:ffff9ceddf400000(0000) knlGS:0000000000000000
[ 6.945017] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6.945017] CR2: 00007fa72ed421f8 CR3: 000000011b20a001 CR4: 00000000001606f0
[ 6.945017] Call Trace:
[ 6.945017] __intel_map_single+0x4e/0x120
[ 6.945017] intel_alloc_coherent+0xa7/0x110
[ 6.945017] dma_pool_alloc+0xd9/0x1e0
[ 6.945017] ehci_qh_alloc+0x55/0x130
[ 6.945017] ehci_setup+0x284/0x7b0
[ 6.945017] ehci_pci_setup+0x8b/0x41d
[ 6.945017] usb_add_hcd.cold.40+0x1c5/0x7b7
[ 6.945017] usb_hcd_pci_probe+0x2a4/0x420
[ 6.945017] local_pci_probe+0x42/0x80
[ 6.945017] pci_device_probe+0x115/0x190
[ 6.945017] really_probe+0xef/0x390
[ 6.945017] driver_probe_device+0xb4/0x100
[ 6.945017] device_driver_attach+0x4f/0x60
[ 6.945017] __driver_attach+0x86/0x140
[ 6.945017] ? device_driver_attach+0x60/0x60
[ 6.945017] bus_for_each_dev+0x77/0xc0
[ 6.945017] ? klist_add_tail+0x3b/0x60
[ 6.945017] bus_add_driver+0x14a/0x1e0
[ 6.945017] ? ehci_hcd_init+0xaa/0xaa
[ 6.945017] ? do_early_param+0x8e/0x8e
[ 6.945017] driver_register+0x6b/0xb0
[ 6.945017] ? ehci_hcd_init+0xaa/0xaa
[ 6.945017] do_one_initcall+0x46/0x1f4
[ 6.945017] ? do_early_param+0x8e/0x8e
[ 6.945017] kernel_init_freeable+0x1ac/0x255
[ 6.945017] ? rest_init+0x9f/0x9f
[ 6.945017] kernel_init+0xa/0x101
[ 6.945017] ret_from_fork+0x35/0x40
[ 6.945017] ---[ end trace 1aa3219cfb92242b ]---
Kernel command line includes intel_iommu=on iommu=pt
On the merge commit of Joerg's pull request for 5.3 (6b04014f3f15),
including:
commit c57b260a7d7d60dfbcf794dd9836c1d9fdbf5434
Author: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Date: Wed Jun 12 08:28:46 2019 +0800
iommu/vt-d: Set domain type for a private domain
Otherwise, domain_get_iommu() will be broken.
Fixes: 942067f1b6b97 ("iommu/vt-d: Identify default domains replaced with private")
The fail to boot error shows as:
[ 7.042371] general protection fault: 0000 [#1] SMP PTI
[ 7.042968] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.0+ #39
[ 7.042968] Hardware name: System manufacturer System Product Name/P8H67-M PRO, BIOS 3904 04/27/2013
[ 7.042968] RIP: 0010:domain_context_mapping_one+0x212/0x4c0
[ 7.042968] Code: 39 c2 0f 8d fc 01 00 00 48 8b 15 49 4d b5 00 eb 0c 83 e8 01 41 39 c2 0f 84 ea 01 00 00 4d 8b 00 49 81 e0 00 f0 ff ff 49 01 d0 <41> f6 00 03 75 e1 b8 f4 ff ff ff e9 be fe ff ff 44 89 e1 45 89 e0
[ 7.042968] RSP: 0018:ffffb021818bb928 EFLAGS: 00010087
[ 7.042968] RAX: 0000000000000002 RBX: ffff9d665f057f00 RCX: 0000000000000001
[ 7.042968] RDX: ffff9d6240000000 RSI: 0000000000000030 RDI: ffff9d665f057f00
[ 7.042968] RBP: 0000000000000003 R08: f0008c563000e000 R09: ffff9d627155a000
[ 7.042968] R10: 0000000000000001 R11: 0000000000000804 R12: 0000000000000000
[ 7.042968] R13: 0000000000000002 R14: 0000000000000000 R15: ffff9d6285934200
[ 7.042968] FS: 0000000000000000(0000) GS:ffff9d665f400000(0000) knlGS:0000000000000000
[ 7.042968] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7.042968] CR2: 00007f99e08a81f8 CR3: 000000040c20a001 CR4: 00000000001606f0
[ 7.042968] Call Trace:
[ 7.042968] ? domain_context_mapping_one+0x4c0/0x4c0
[ 7.042968] pci_for_each_dma_alias+0x30/0x140
[ 7.042968] dmar_insert_one_dev_info+0x33f/0x4b0
[ 7.042968] get_private_domain_for_dev.part.75+0x136/0x2f0
[ 7.042968] ? __dmar_remove_one_dev_info+0x106/0x250
[ 7.042968] iommu_need_mapping+0xac/0xc0
[ 7.042968] intel_alloc_coherent+0x20/0x110
[ 7.042968] xhci_mem_init+0x1ba/0xee1
[ 7.042968] ? xhci_dbg_trace+0x6b/0xb0
[ 7.042968] ? recalibrate_cpu_khz+0x10/0x10
[ 7.042968] ? ktime_get+0x36/0xa0
[ 7.042968] ? xhci_pci_suspend+0xd0/0xd0
[ 7.042968] xhci_init+0x81/0x170
[ 7.042968] xhci_gen_setup+0x1fe/0x360
[ 7.042968] xhci_pci_setup+0x4d/0x120
[ 7.042968] usb_add_hcd.cold.40+0x1c5/0x7b7
[ 7.042968] usb_hcd_pci_probe+0x214/0x420
[ 7.042968] xhci_pci_probe+0x29/0x1f0
[ 7.042968] local_pci_probe+0x42/0x80
[ 7.042968] pci_device_probe+0x115/0x190
[ 7.042968] really_probe+0xef/0x390
[ 7.042968] driver_probe_device+0xb4/0x100
[ 7.042968] device_driver_attach+0x4f/0x60
[ 7.042968] __driver_attach+0x86/0x140
[ 7.042968] ? device_driver_attach+0x60/0x60
[ 7.042968] bus_for_each_dev+0x77/0xc0
[ 7.042968] ? klist_add_tail+0x3b/0x60
[ 7.042968] bus_add_driver+0x14a/0x1e0
[ 7.042968] ? xhci_debugfs_create_root+0x20/0x20
[ 7.042968] ? do_early_param+0x8e/0x8e
[ 7.042968] driver_register+0x6b/0xb0
[ 7.042968] ? xhci_debugfs_create_root+0x20/0x20
[ 7.042968] do_one_initcall+0x46/0x1f4
[ 7.042968] ? do_early_param+0x8e/0x8e
[ 7.042968] kernel_init_freeable+0x1ac/0x255
[ 7.042968] ? rest_init+0x9f/0x9f
[ 7.042968] kernel_init+0xa/0x101
[ 7.042968] ret_from_fork+0x35/0x40
[ 7.042968] Modules linked in:
[ 7.042968] ---[ end trace 6d6cf443442a773d ]---
Thanks,
Alex