Messages in this thread Patch in this message | | | Subject | Re: BUG in drivers/dma/ioat/dma_v2.c:314 | From | Dan Williams <> | Date | Tue, 06 Jul 2010 17:51:41 -0700 |
| |
[ adding Matthew as one of last people to touch mm/dmapool.c ]
On Tue, 2010-07-06 at 16:40 -0700, Chris Li wrote: > On Mon, Jul 5, 2010 at 3:16 AM, David Woodhouse <dwmw2@infradead.org> wrote: > > On Fri, 2010-07-02 at 20:00 +0100, Chris Li wrote: > >> But I don't see the line that print out BIOS is lying. > > > > Hrm. Want to augment the dmar_find_matched_drhd_unit() function to > > _always_ print the DRHD returned for the offending PCI device? And if > > that still doesn't show, make it print pdev->vendor, pdev->device and > > the returned DRHD pointer for _every_ call? > > I just did some experiment, my PCI device ID is PCI_DEVICE_ID_INTEL_ESB2_0 > (0x2670) instead of PCI_DEVICE_ID_INTEL_IOAT_SNB.
No, it should be PCI_DEVICE_ID_INTEL_IOAT_SNB (0x402f) for the dma engine at 00:0f.0 . PCI_DEVICE_ID_INTEL_ESB2_0 is the LPC controller at 00:1f.0,
> That seems to be the reason preventing the warning to be print out. I am not > sure the warning should be always print out. Just curious why it did > not trigger.
It should always trigger, and I have verified as much with the attached replacement patch (by forcing the error on a working system), but we run into a new problem. dma_pool_alloc() assumes that any dma_mapping error is transient. Do we need a new type of dma_mapping_error() that indicates permanent failure versus ENOMEM? The driver can handle the allocation failure, but it never gets the chance.
------------[ cut here ]------------ WARNING: at drivers/pci/dmar.c:574 dmar_find_matched_drhd_unit+0xe4/0xfa() Hardware name: [redacted to protect the innocent] BIOS wrongly assigned I/OAT IOMMU 5: reg_base_addr fe71a000 cap 4900800c2f0462 ecap e01 Modules linked in: ioatdma(+) dca ipv6 snd_pcsp snd_pcm snd_timer snd soundcore i2c_i801 snd_page_alloc serio_raw i2c_core joydev Pid: 1166, comm: modprobe Not tainted 2.6.35-rc3+ #2 Call Trace: [<ffffffff8104bfd0>] warn_slowpath_common+0x85/0x9d [<ffffffff8104c043>] warn_slowpath_fmt_taint+0x3f/0x41 [<ffffffff8125dd4b>] dmar_find_matched_drhd_unit+0xe4/0xfa [<ffffffff8126179d>] get_domain_for_dev.clone.3+0x111/0x471 [<ffffffff81261cbb>] get_valid_domain_for_dev+0x26/0x9a [<ffffffff81261f51>] __intel_map_single+0x4c/0x175 [<ffffffff81262184>] intel_alloc_coherent+0xc7/0xef [<ffffffff810edcd2>] dma_pool_alloc+0x179/0x2ab [<ffffffffa00ed606>] ? kzalloc+0x14/0x16 [ioatdma] [<ffffffffa00efe58>] ioat2_alloc_chan_resources+0x4f/0x219 [ioatdma] [<ffffffffa00f33b9>] ioat_dma_self_test+0x94/0x2af [ioatdma] [<ffffffff8109bff2>] ? devm_request_threaded_irq+0x98/0xaa [<ffffffffa00f31cd>] ioat_probe+0x338/0x3aa [ioatdma] [<ffffffffa00f3657>] ioat2_dma_probe+0x83/0x106 [ioatdma] [<ffffffffa00f2ded>] ioat_pci_probe+0x133/0x195 [ioatdma] [<ffffffff8124b539>] local_pci_probe+0x17/0x1b [<ffffffff8124c2f5>] pci_device_probe+0xcd/0xfd [<ffffffff812ee5f5>] ? driver_sysfs_add+0x4c/0x71 [<ffffffff812ee81a>] driver_probe_device+0x12f/0x240 [<ffffffff812ee97a>] __driver_attach+0x4f/0x6b [<ffffffff812ee92b>] ? __driver_attach+0x0/0x6b [<ffffffff812edc66>] bus_for_each_dev+0x53/0x88 [<ffffffff812ee554>] driver_attach+0x1e/0x20 [<ffffffff812ee19a>] bus_add_driver+0xd5/0x23b [<ffffffff812eec54>] driver_register+0x9d/0x10e [<ffffffff8124c521>] __pci_register_driver+0x58/0xc8 [<ffffffffa00fc000>] ? ioat_init_module+0x0/0x85 [ioatdma] [<ffffffffa00fc000>] ? ioat_init_module+0x0/0x85 [ioatdma] [<ffffffffa00fc06d>] ioat_init_module+0x6d/0x85 [ioatdma] [<ffffffff81002069>] do_one_initcall+0x5e/0x159 [<ffffffff8107bd01>] sys_init_module+0xa1/0x1e0 [<ffffffff81009c32>] system_call_fastpath+0x16/0x1b ---[ end trace 02c1ac1f56dc9544 ]--- Disabling lock debugging due to kernel taint IOMMU: can't find DMAR for device 0000:00:0f.0 Allocating domain for 0000:00:0f.0 failed IOMMU: can't find DMAR for device 0000:00:0f.0 Allocating domain for 0000:00:0f.0 failed [...ad infinitum...]
-- Dan
diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c index 0a19708..f183ac9 100644 --- a/drivers/pci/dmar.c +++ b/drivers/pci/dmar.c @@ -532,7 +532,7 @@ static int dmar_pci_device_match(struct pci_dev *devices[], int cnt, struct dmar_drhd_unit * dmar_find_matched_drhd_unit(struct pci_dev *dev) { - struct dmar_drhd_unit *dmaru = NULL; + struct dmar_drhd_unit *dmaru, *found = NULL; struct acpi_dmar_hardware_unit *drhd; dev = pci_physfn(dev); @@ -544,14 +544,38 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev) if (dmaru->include_all && drhd->segment == pci_domain_nr(dev->bus)) - return dmaru; - - if (dmar_pci_device_match(dmaru->devices, + found = dmaru; + else if (dmar_pci_device_match(dmaru->devices, dmaru->devices_cnt, dev)) - return dmaru; + found = dmaru; + + + if (found) + break; + } + + /* We know that this device only exists on this chipset, has its + * own IOMMU, and is uniquely identified by bit 54 being set in + * its capability mask. Catch BIOSes that specify the incorrect + * IOMMU unit. + */ + if (found && + dev->vendor == PCI_VENDOR_ID_INTEL && + dev->device == PCI_DEVICE_ID_INTEL_IOAT_SNB && + !test_bit(54, (unsigned long *) &found->iommu->cap)) { + struct intel_iommu *iommu = found->iommu; + + WARN_TAINT_ONCE(1, TAINT_FIRMWARE_WORKAROUND, + "BIOS wrongly assigned I/OAT IOMMU " + "%d: reg_base_addr %llx cap %llx ecap %llx\n", + iommu->seq_id, + (unsigned long long)found->reg_base_addr, + (unsigned long long)iommu->cap, + (unsigned long long)iommu->ecap); + found = NULL; } - return NULL; + return found; } int __init dmar_dev_scope_init(void) | |