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path: root/drivers/pci
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2009-03-19PCI: enhance physical slot debug informationAlex Chiang
Convert usages of pr_debug to dev_dbg and add physical slot name. Note that we use dev_dbg on the struct pci_bus and still manually print out the PCI slot number (instead of calling dev_dbg on a pci_dev) because a struct pci_bus with empty physical slots will not have any pci_devs. Reviewed-by: Andrew Patterson <andrew.patterson@hp.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: pciehp: make cmd_busy flag one bitKenji Kaneshige
The cmd_busy field in struct controller takes only two values 0 or 1. So it should be one bit. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: pciehp: enable software notification on empty slotsKenji Kaneshige
Current pciehp disables software notification of adapter presence changed event and MRL changed event when slot is turned off. Because of this, there is no way to detect those events on empty slots in the current pciehp implementation. According to the past discussion(*), this behavior was introduced to prevent endless loop that could happen if pcie_isr() runs after power fault is detected on a certain platform whose stickey power-fault bit remains on till the slot is powered on again. (*) http://sourceforge.net/mailarchive/message.php?msg_id=20051130135409.A14918%40unix-os.sc.intel.com I think this endless loop can be avoided using one bit flag that indicates power fault had been detected, instead of disabling software notification of adapter present changed event and MRL changed event. With this patch, we can enable software notification mechanism of presence changed and MRL changed event on the empty slots again. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: pciehp: fix possible endless loop in pcie_isrKenji Kaneshige
Fix possible endless loop in pcie_isr. Currently, pcie_isr() (interrupt service routine of pciehp) can end up in an endless loop if the Slot Status register is set again immediately after being cleared. According to the past discussion (see below URL) this case can happen if the power fault detected bit is set during handling. http://sourceforge.net/mailarchive/message.php?msg_id=20051130135409.A14918%40unix-os.sc.intel.com Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: introduce missing kfreeJulia Lawall
Error handling code following a kmalloc should free the allocated data. Since the subsequent code that could provoke an error does not use the allocated data, the allocation is just moved below it. The semantic match that finds the problem is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @r exists@ local idexpression x; statement S; expression E; identifier f,l; position p1,p2; expression *ptr != NULL; @@ ( if ((x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...)) == NULL) S | x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...); ... if (x == NULL) S ) <... when != x when != if (...) { <+...x...+> } x->f = E ...> ( return \(0\|<+...x...+>\|ptr\); | return@p2 ...; ) @script:python@ p1 << r.p1; p2 << r.p2; @@ print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Reviewed-by: Matthew Wilcox <willy@linux.intel.com> Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: add missing KERN_* constants to printksFrank Seidel
According to kerneljanitors todo list all printk calls (beginning a new line) should have an according KERN_* constant. Those are the missing pieces here for the pci subsystem. Signed-off-by: Frank Seidel <frank@f-seidel.de> Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: check if a bus is added when removing itYu Zhao
When removing a bus, 'is_added' should be checked to make sure the bus has been successfully added by pci_bus_add_child() who will sets 'is_added'. Signed-off-by: Yu Zhao <yu.zhao@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI/MSI: Use #ifdefs instead of weak functionsMichael Ellerman
Weak functions aren't all they're cracked up to be. They lead to incorrect binaries with some toolchains, they require us to have empty functions we otherwise wouldn't, and the unused code is not elided (as of gcc 4.3.2 anyway). So replace the weak MSI arch hooks with the #define foo foo idiom. We no longer need empty versions of arch_setup/teardown_msi_irq(). This is less source (by 1 line!), and results in smaller binaries too: text data bss dec hex filename 9354300 1693916 678424 11726640 b2ef30 build/powerpc/vmlinux-before 9354052 1693852 678424 11726328 b2edf8 build/powerpc/vmlinux-after Also smaller on x86_64 and arm (iop13xx). Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI/PCIe portdrv: Fix allocation of interruptsRafael J. Wysocki
If MSI-X interrupt mode is used by the PCI Express port driver, too many vectors are allocated and it is not ensured that the right vectors will be used for the right services. Namely, the PCI Express specification states that both PCI Express native PME and PCI Express hotplug will always use the same MSI or MSI-X message for signalling interrupts, which implies that the same vector will be used by both of them. Also, the VC service does not use interrupts at all. Moreover, is not clear which of the vectors allocated by pci_enable_msix() in the current code will be used for PME and hotplug and which of them will be used for AER if all of these services are configured. For these reasons, rework the allocation of interrupts for PCI Express ports so that if MSI-X are enabled, the right vectors will be used for the right purposes. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI/MSI: Introduce pci_msix_table_size()Rafael J. Wysocki
Introduce new function pci_msix_table_size() returning the size of the MSI-X table of given PCI device or 0 if the device doesn't support MSI-X. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers
More dev_set_name conversion. Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: PCIe portdrv: Remove struct pcie_port_service_idRafael J. Wysocki
The PCI Express port driver uses 'struct pcie_port_service_id' for matching port service devices and drivers, but this structure contains fields that duplicate information from the port device itself (vendor, device, subvendor, subdevice) and fields that are not used by any existing port service driver (class, class_mask, drvier_data). Also, both existing port service drivers (AER and PCIe HP) don't even use the vendor and device fields for device matching. Therefore 'struct pcie_port_service_id' can be removed altogether and the only useful members of it (port_type, service) can be introduced directly into the port service device and port service driver structures. That simplifies the code quite a bit and reduces its size. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: PCIe portdrv: Simplily probe callback of service driversRafael J. Wysocki
The second argument of the ->probe() callback in struct pcie_port_service_driver is unnecessary and never used. Remove it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: PCIe portdrv: Remove unnecessary functionRafael J. Wysocki
The function pcie_portdrv_save_config() in portdrv_pci.c is not necessary. Remove it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: PCIe portdrv: Do not enable port device before setting up interruptsRafael J. Wysocki
The PCI Express port driver calls pci_enable_device() before setting up interrupts, which is wrong, because if there is an interrupt pin configured for the port, pci_enable_device() will likely set up an interrupt link for it. However, this shouldn't be done if either MSI or MSI-X interrupt mode is chosen for the port. The solution is to call pci_enable_device() after setting up interrupts, because in that case the interrupt link won't be set up if MSI or MSI-X are enabled. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: PCIe portdrv: Aviod using service devices with wrong interruptsRafael J. Wysocki
The PCI Express port driver should not attempt to register service devices that require the ability to generate interrupts if generating interrupts is not possible. Namely, if the port has no interrupt pin configured and we cannot set up MSI or MSI-X for it, there is no way it can generate interrupts and in such a case the port services that rely on interrupts (PME, PCIe HP, AER) should not be enabled for it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: PCIe portdrv: Use driver data to simplify codeRafael J. Wysocki
PCI Express port driver extension, as defined by struct pcie_port_device_ext in portdrv.h, is allocated and initialized, but never used (it also is never freed). Extend it to hold the PCI Express port type as well as the port interrupt mode, change its name and use it to simplify the code in portdrv_core.c . Additionally, remove the redundant interrupt_mode member of struct pcie_device defined in include/linux/pcieport_if.h . Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-19PCI: __FUNCTION__ is gcc-specific, use __func__Harvey Harrison
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-03-18Merge branch 'linus' into core/iommuIngo Molnar
2009-03-17x86, dmar: use atomic allocations for QI and Intr-remapping initSuresh Siddha
Impact: invalid use of GFP_KERNEL in interrupt context Queued invalidation and interrupt-remapping will get initialized with interrupts disabled (while enabling interrupt-remapping). So use GFP_ATOMIC instead of GFP_KERNEL for memory alloacations. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17x86, intr-remapping: fix free_irte() to clear all the IRTE entriesSuresh Siddha
Impact: fix interrupt table entry leak Fix the typo which was not clearing all the interrupt remapping table entries corresponding to an irq. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17x86, dmar: start with sane state while enabling dma and interrupt-remappingSuresh Siddha
Impact: cleanup/sanitization Start from a sane state while enabling dma and interrupt-remapping, by clearing the previous recorded faults and disabling previously enabled queued invalidation and interrupt-remapping. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17x86, dmar: routines for disabling queued invalidation and intr remappingSuresh Siddha
Impact: new interfaces (not yet used) Routines for disabling queued invalidation and interrupt remapping. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17x86, x2apic: enable fault handling for intr-remappingSuresh Siddha
Impact: interface augmentation (not yet used) Enable fault handling flow for intr-remapping aswell. Fault handling code now shared by both dma-remapping and intr-remapping. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17x86, dmar: move page fault handling code to dmar.cSuresh Siddha
Impact: code movement Move page fault handling code to dmar.c This will be shared both by DMA-remapping and Intr-remapping code. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-17x86, x2apic: fix lock ordering during IRQ migrationSuresh Siddha
Impact: fix potential deadlock on x2apic fix "hard-safe -> hard-unsafe lock order detected" with irq_2_ir_lock On x2apic enabled system: [ INFO: hard-safe -> hard-unsafe lock order detected ] 2.6.27-03151-g4480f15b #1 ------------------------------------------------------ swapper/1 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: (irq_2_ir_lock){--..}, at: [<ffffffff8038ebc0>] get_irte+0x2f/0x95 and this task is already holding: (&irq_desc_lock_class){+...}, at: [<ffffffff802649ed>] setup_irq+0x67/0x281 which would create a new lock dependency: (&irq_desc_lock_class){+...} -> (irq_2_ir_lock){--..} but this new dependency connects a hard-irq-safe lock: (&irq_desc_lock_class){+...} ... which became hard-irq-safe at: [<ffffffffffffffff>] 0xffffffffffffffff to a hard-irq-unsafe lock: (irq_2_ir_lock){--..} ... which became hard-irq-unsafe at: ... [<ffffffff802547b5>] __lock_acquire+0x571/0x706 [<ffffffff8025499f>] lock_acquire+0x55/0x71 [<ffffffff8062f2c4>] _spin_lock+0x2c/0x38 [<ffffffff8038ee50>] alloc_irte+0x8a/0x14b [<ffffffff8021f733>] setup_IO_APIC_irq+0x119/0x30e [<ffffffff8090860e>] setup_IO_APIC+0x146/0x6e5 [<ffffffff809058fc>] native_smp_prepare_cpus+0x24e/0x2e9 [<ffffffff808f982c>] kernel_init+0x5a/0x176 [<ffffffff8020c289>] child_rip+0xa/0x11 [<ffffffffffffffff>] 0xffffffffffffffff Fix this theoretical lock order issue by using spin_lock_irqsave() instead of spin_lock() Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-03-16Merge branches 'irq/genirq' and 'linus' into irq/coreIngo Molnar
2009-03-13Merge branch 'x86/core' into x86/kconfigIngo Molnar
2009-03-13Merge branch 'cpus4096' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-x86 into cpus4096
2009-03-13Merge commit 'v2.6.29-rc8' into cpus4096Ingo Molnar
2009-03-13cpumask: replace node_to_cpumask with cpumask_of_node.Rusty Russell
Impact: cleanup node_to_cpumask (and the blecherous node_to_cpumask_ptr which contained a declaration) are replaced now everyone implements cpumask_of_node. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-12PCIe: portdrv: call pci_disable_device during removeAlex Chiang
The PCIe port driver calls pci_enable_device() during probe but never calls pci_disable_device() during remove. Cc: stable@kernel.org Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2009-03-12pci: Fix typo in message while disabling HT MSI mappingPrakash Punnoor
"Enabling" should read "Disabling" Signed-off-by: Prakash Punnoor <prakash@punnoor.de> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2009-03-12pci: don't disable too many HT MSI mappingPrakash Punnoor
Prakash's system needs MSI disabled on some bridges, but not all. This seems to be the minimal fix for 2.6.29, but should be replaced during 2.6.30. Signed-off-by: Prakash Punnoor <prakash@punnoor.de> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2009-03-12powerpc/pseries: The RPA PCI hotplug driver depends on EEHMichael Ellerman
The RPA PCI hotplug driver calls EEH routines, so should depend on EEH. Also PPC_PSERIES implies PPC64, so remove that. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2009-03-12PCIe: AER: during disable, check subordinate before walkingAlex Chiang
Commit 47a8b0cc (Enable PCIe AER only after checking firmware support) wants to walk the PCI bus in the remove path to disable AER, and calls pci_walk_bus for downstream bridges. Unfortunately, in the remove path, we remove devices and bridges in a depth-first manner, starting with the furthest downstream bridge and working our way backwards. The furthest downstream bridges will not have a dev->subordinate, and we hit a NULL deref in pci_walk_bus. Check for dev->subordinate first before attempting to walk the PCI hierarchy below us. Acked-by: Andrew Patterson <andrew.patterson@hp.com> Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2009-03-12PCI: Add PCI quirk to disable L0s ASPM state for 82575 and 82598Alexander Duyck
This patch is intended to disable L0s ASPM link state for 82598 (ixgbe) parts due to the fact that it is possible to corrupt TX data when coming back out of L0s on some systems. The workaround had been added for 82575 (igb) previously, but did not use the ASPM api. This quirk uses the ASPM api to prevent the ASPM subsystem from re-enabling the L0s state. Instead of adding the fix in igb to the ixgbe driver as well it was decided to move it into a pci quirk. It is necessary to move the fix out of the driver and into a pci quirk in order to prevent the issue from occuring prior to driver load to handle the possibility of the device being passed to a VM via direct assignment. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> CC: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2009-03-05Merge branch 'linus' into core/iommuIngo Molnar
2009-03-01Merge branch 'x86/urgent' into x86/patIngo Molnar
2009-02-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: PCI: AMD 813x B2 devices do not need boot interrupt quirk PCI: Enable PCIe AER only after checking firmware support PCI: pciehp: Handle interrupts that happen during initialization. PCI: don't enable too many HT MSI mappings PCI: add some sysfs ABI docs PCI quirk: enable MSI on 8132
2009-02-26PCI: AMD 813x B2 devices do not need boot interrupt quirkStefan Assmann
Turns out that the new AMD 813x devices do not need the quirk_disable_amd_813x_boot_interrupt quirk to be run on them. If it is, no interrupts are seen on the PCI-X adapter. From: Stefan Assmann <sassmann@novell.com> Reported-by: Jamie Wellnitz <Jamie.Wellnitz@emulex.com> Tested-by: Jamie Wellnitz <Jamie.Wellnitz@emulex.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2009-02-25Merge git://git.infradead.org/iommu-2.6Linus Torvalds
* git://git.infradead.org/iommu-2.6: intel-iommu: fix endless "Unknown DMAR structure type" loop VT-d: handle Invalidation Queue Error to avoid system hang intel-iommu: fix build error with INTR_REMAP=y and DMAR=n
2009-02-24PCI: Enable PCIe AER only after checking firmware supportAndrew Patterson
The PCIe port driver currently sets the PCIe AER error reporting bits for any root or switch port without first checking to see if firmware will grant control. This patch moves setting these bits to the AER service driver aer_enable_port routine. The bits are then set for the root port and any downstream switch ports after the check for firmware support (aer_osc_setup) is made. The patch also unsets the bits in a similar fashion when the AER service driver is unloaded. Reviewed-by: Alex Chiang <achiang@hp.com> Signed-off-by: Andrew Patterson <andrew.patterson@hp.com> Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2009-02-24PCI: pciehp: Handle interrupts that happen during initialization.Eric W. Biederman
Move the enabling of interrupts after all of the data structures are setup so that we can safely run the interrupt handler as soon as it is registered. Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Tested-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2009-02-24PCI: don't enable too many HT MSI mappingsYinghai Lu
Prakash reported that his c51-mcp51 ondie sound card doesn't work with MSI. But if he hacks out the HT-MSI quirk, MSI works fine. So this patch reworks the nv_msi_ht_cap_quirk(). It will now only enable ht_msi on own its root device, avoiding enabling it on devices following that root dev. Reported-by: Prakash Punnoor <prakash@punnoor.de> Tested-by: Prakash Punnoor <prakash@punnoor.de> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
2009-02-22Merge branch 'linus' into x86/apicIngo Molnar
Conflicts: arch/x86/mach-default/setup.c Semantic conflict resolution: arch/x86/kernel/setup.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-18PCI quirk: enable MSI on 8132Yinghai Lu
David reported that LSI SAS doesn't work with MSI. It turns out that his BIOS doesn't enable it, but the HT MSI 8132 does support HT MSI. Add quirk to enable it Cc: stable@kernel.org Reported-by: David Lang <david@lang.hm> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-02-17Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: iommu: fix Intel IOMMU write-buffer flushing futex: fix reference leak Trivial conflicts fixed manually in drivers/pci/intel-iommu.c
2009-02-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: PCI: Documentation: fix minor PCIe HOWTO thinko PCI: fix missing kernel-doc and typos PCI: fix struct pci_platform_pm_ops kernel-doc PCI: fix rom.c kernel-doc warning PCI/MSI: fix msi_mask() shift fix
2009-02-17Fix Intel IOMMU write-buffer flushingDavid Woodhouse
This is the cause of the DMA faults and disk corruption that people have been seeing. Some chipsets neglect to report the RWBF "capability" -- the flag which says that we need to flush the chipset write-buffer when changing the DMA page tables, to ensure that the change is visible to the IOMMU. Override that bit on the affected chipsets, and everything is happy again. Thanks to Chris and Bhavesh and others for helping to debug. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Tested-by: Chris Wright <chrisw@sous-sol.org> Reviewed-by: Bhavesh Davda <bhavesh@vmware.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>