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Commit Graph

2601 Commits

Author SHA1 Message Date
Lu Baolu
cfb94a372f iommu/vt-d: Use bounce buffer for untrusted devices
The Intel VT-d hardware uses paging for DMA remapping.
The minimum mapped window is a page size. The device
drivers may map buffers not filling the whole IOMMU
window. This allows the device to access to possibly
unrelated memory and a malicious device could exploit
this to perform DMA attacks. To address this, the
Intel IOMMU driver will use bounce pages for those
buffers which don't fill whole IOMMU pages.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Xu Pengfei <pengfei.xu@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-09-11 12:34:31 +02:00
Lu Baolu
3b53034c26 iommu/vt-d: Add trace events for device dma map/unmap
This adds trace support for the Intel IOMMU driver. It
also declares some events which could be used to trace
the events when an IOVA is being mapped or unmapped in
a domain.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-09-11 12:34:30 +02:00
Lu Baolu
c5a5dc4cbb iommu/vt-d: Don't switch off swiotlb if bounce page is used
The bounce page implementation depends on swiotlb. Hence, don't
switch off swiotlb if the system has untrusted devices or could
potentially be hot-added with any untrusted devices.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-09-11 12:34:30 +02:00
Lu Baolu
e5e04d0519 iommu/vt-d: Check whether device requires bounce buffer
This adds a helper to check whether a device needs to
use bounce buffer. It also provides a boot time option
to disable the bounce buffer. Users can use this to
prevent the iommu driver from using the bounce buffer
for performance gain.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Xu Pengfei <pengfei.xu@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-09-11 12:34:29 +02:00
Nadav Amit
2c70010867 iommu/vt-d: Fix wrong analysis whether devices share the same bus
set_msi_sid_cb() is used to determine whether device aliases share the
same bus, but it can provide false indications that aliases use the same
bus when in fact they do not. The reason is that set_msi_sid_cb()
assumes that pdev is fixed, while actually pci_for_each_dma_alias() can
call fn() when pdev is set to a subordinate device.

As a result, running an VM on ESX with VT-d emulation enabled can
results in the log warning such as:

  DMAR: [INTR-REMAP] Request device [00:11.0] fault index 3b [fault reason 38] Blocked an interrupt request due to source-id verification failure

This seems to cause additional ata errors such as:
  ata3.00: qc timeout (cmd 0xa1)
  ata3.00: failed to IDENTIFY (I/O error, err_mask=0x4)

These timeouts also cause boot to be much longer and other errors.

Fix it by checking comparing the alias with the previous one instead.

Fixes: 3f0c625c6a ("iommu/vt-d: Allow interrupts from the entire bus for aliased devices")
Cc: stable@vger.kernel.org
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Nadav Amit <namit@vmware.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-30 15:47:37 +02:00
Linus Torvalds
e83b009c5c dma-mapping fixes for 5.3-rc
- fix the handling of the bus_dma_mask in dma_get_required_mask, which
    caused a regression in this merge window (Lucas Stach)
  - fix a regression in the handling of DMA_ATTR_NO_KERNEL_MAPPING (me)
  - fix dma_mmap_coherent to not cause page attribute mismatches on
    coherent architectures like x86 (me)
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Merge tag 'dma-mapping-5.3-4' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:

 - fix the handling of the bus_dma_mask in dma_get_required_mask, which
   caused a regression in this merge window (Lucas Stach)

 - fix a regression in the handling of DMA_ATTR_NO_KERNEL_MAPPING (me)

 - fix dma_mmap_coherent to not cause page attribute mismatches on
   coherent architectures like x86 (me)

* tag 'dma-mapping-5.3-4' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: fix page attributes for dma_mmap_*
  dma-direct: don't truncate dma_required_mask to bus addressing capabilities
  dma-direct: fix DMA_ATTR_NO_KERNEL_MAPPING
2019-08-14 10:31:11 -07:00
Christoph Hellwig
33dcb37cef dma-mapping: fix page attributes for dma_mmap_*
All the way back to introducing dma_common_mmap we've defaulted to mark
the pages as uncached.  But this is wrong for DMA coherent devices.
Later on DMA_ATTR_WRITE_COMBINE also got incorrect treatment as that
flag is only treated special on the alloc side for non-coherent devices.

Introduce a new dma_pgprot helper that deals with the check for coherent
devices so that only the remapping cases ever reach arch_dma_mmap_pgprot
and we thus ensure no aliasing of page attributes happens, which makes
the powerpc version of arch_dma_mmap_pgprot obsolete and simplifies the
remaining ones.

Note that this means arch_dma_mmap_pgprot is a bit misnamed now, but
we'll phase it out soon.

Fixes: 64ccc9c033 ("common: dma-mapping: add support for generic dma_mmap_* calls")
Reported-by: Shawn Anastasio <shawn@anastas.io>
Reported-by: Gavin Li <git@thegavinli.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> # arm64
2019-08-10 19:52:45 +02:00
Lu Baolu
3a18844dcf iommu/vt-d: Fix possible use-after-free of private domain
Multiple devices might share a private domain. One real example
is a pci bridge and all devices behind it. When remove a private
domain, make sure that it has been detached from all devices to
avoid use-after-free case.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Fixes: 942067f1b6 ("iommu/vt-d: Identify default domains replaced with private")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-09 17:35:25 +02:00
Lu Baolu
ae23bfb68f iommu/vt-d: Detach domain before using a private one
When the default domain of a group doesn't work for a device,
the iommu driver will try to use a private domain. The domain
which was previously attached to the device must be detached.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Fixes: 942067f1b6 ("iommu/vt-d: Identify default domains replaced with private")
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lkml.org/lkml/2019/8/2/1379
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-09 17:35:25 +02:00
Robin Murphy
ab2cbeb0ed iommu/dma: Handle SG length overflow better
Since scatterlist dimensions are all unsigned ints, in the relatively
rare cases where a device's max_segment_size is set to UINT_MAX, then
the "cur_len + s_length <= max_len" check in __finalise_sg() will always
return true. As a result, the corner case of such a device mapping an
excessively large scatterlist which is mergeable to or beyond a total
length of 4GB can lead to overflow and a bogus truncated dma_length in
the resulting segment.

As we already assume that any single segment must be no longer than
max_len to begin with, this can easily be addressed by reshuffling the
comparison.

Fixes: 809eac54cd ("iommu/dma: Implement scatterlist segment merging")
Reported-by: Nicolin Chen <nicoleotsuka@gmail.com>
Tested-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-09 17:31:39 +02:00
Lu Baolu
bfeaec7f7d iommu/vt-d: Correctly check format of page table in debugfs
PASID support and enable bit in the context entry isn't the right
indicator for the type of tables (legacy or scalable mode). Check
the DMA_RTADDR_SMT bit in the root context pointer instead.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Sai Praneeth <sai.praneeth.prakhya@intel.com>
Fixes: dd5142ca5d ("iommu/vt-d: Add debugfs support to show scalable mode DMAR table internals")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-09 17:29:25 +02:00
Lu Baolu
458b7c8e0d iommu/vt-d: Detach domain when move device out of group
When removing a device from an iommu group, the domain should
be detached from the device. Otherwise, the stale domain info
will still be cached by the driver and the driver will refuse
to attach any domain to the device again.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Fixes: b7297783c2 ("iommu/vt-d: Remove duplicated code for device hotplug")
Reported-and-tested-by: Vlad Buslov <vladbu@mellanox.com>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lkml.org/lkml/2019/7/26/1133
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-06 17:27:10 +02:00
Anders Roxell
11f4fe9ba3 iommu/arm-smmu: Mark expected switch fall-through
Now that -Wimplicit-fallthrough is passed to GCC by default, the
following warning shows up:

../drivers/iommu/arm-smmu-v3.c: In function ‘arm_smmu_write_strtab_ent’:
../drivers/iommu/arm-smmu-v3.c:1189:7: warning: this statement may fall
 through [-Wimplicit-fallthrough=]
    if (disable_bypass)
       ^
../drivers/iommu/arm-smmu-v3.c:1191:3: note: here
   default:
   ^~~~~~~

Rework so that the compiler doesn't warn about fall-through. Make it
clearer by calling 'BUG_ON()' when disable_bypass is set, and always
'break;'

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-06 17:26:38 +02:00
Robin Murphy
8af23fad62 iommu/dma: Handle MSI mappings separately
MSI pages must always be mapped into a device's *current* domain, which
*might* be the default DMA domain, but might instead be a VFIO domain
with its own MSI cookie. This subtlety got accidentally lost in the
streamlining of __iommu_dma_map(), but rather than reintroduce more
complexity and/or special-casing, it turns out neater to just split this
path out entirely.

Since iommu_dma_get_msi_page() already duplicates much of what
__iommu_dma_map() does, it can easily just make the allocation and
mapping calls directly as well. That way we can further streamline the
helper back to exclusively operating on DMA domains.

Fixes: b61d271e59 ("iommu/dma: Move domain lookup into __iommu_dma_{map,unmap}")
Reported-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-08-06 17:22:49 +02:00
Linus Torvalds
2a11c76e53 virtio, vhost: bugfixes
Fixes in the iommu and balloon devices.
 Disable the meta-data optimization for now - I hope we can get it fixed
 shortly, but there's no point in making users suffer crashes while we
 are working on that.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost fixes from Michael Tsirkin:

 - Fixes in the iommu and balloon devices.

 - Disable the meta-data optimization for now - I hope we can get it
   fixed shortly, but there's no point in making users suffer crashes
   while we are working on that.

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: disable metadata prefetch optimization
  iommu/virtio: Update to most recent specification
  balloon: fix up comments
  mm/balloon_compaction: avoid duplicate page removal
2019-07-29 11:34:12 -07:00
Suthikulpanit, Suravee
6692981295 iommu/amd: Add support for X2APIC IOMMU interrupts
AMD IOMMU requires IntCapXT registers to be setup in order to generate
its own interrupts (for Event Log, PPR Log, and GA Log) with 32-bit
APIC destination ID. Without this support, AMD IOMMU MSI interrupts
will not be routed correctly when booting the system in X2APIC mode.

Cc: Joerg Roedel <joro@8bytes.org>
Fixes: 90fcffd9cf ('iommu/amd: Add support for IOMMU XT mode')
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-23 17:41:52 +02:00
Sai Praneeth Prakhya
7f6cade5b6 iommu/vt-d: Print pasid table entries MSB to LSB in debugfs
Commit dd5142ca5d ("iommu/vt-d: Add debugfs support to show scalable mode
DMAR table internals") prints content of pasid table entries from LSB to
MSB where as other entries are printed MSB to LSB. So, to maintain
uniformity among all entries and to not confuse the user, print MSB first.

Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Sohil Mehta <sohil.mehta@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Fixes: dd5142ca5d ("iommu/vt-d: Add debugfs support to show scalable mode DMAR table internals")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 17:52:57 +02:00
Jean-Philippe Brucker
ae24fb49d0 iommu/virtio: Update to most recent specification
Following specification review a few things were changed in v8 of the
virtio-iommu series [1], but have been omitted when merging the base
driver. Add them now:

* Remove the EXEC flag.
* Add feature bit for the MMIO flag.
* Change domain_bits to domain_range.
* Add NOMEM status flag.

[1] https://lore.kernel.org/linux-iommu/20190530170929.19366-1-jean-philippe.brucker@arm.com/

Fixes: edcd69ab9a ("iommu: Add virtio-iommu driver")
Reported-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 11:52:27 -04:00
Chris Wilson
9eed17d37c iommu/iova: Remove stale cached32_node
Since the cached32_node is allowed to be advanced above dma_32bit_pfn
(to provide a shortcut into the limited range), we need to be careful to
remove the to be freed node if it is the cached32_node.

[   48.477773] BUG: KASAN: use-after-free in __cached_rbnode_delete_update+0x68/0x110
[   48.477812] Read of size 8 at addr ffff88870fc19020 by task kworker/u8:1/37
[   48.477843]
[   48.477879] CPU: 1 PID: 37 Comm: kworker/u8:1 Tainted: G     U            5.2.0+ #735
[   48.477915] Hardware name: Intel Corporation NUC7i5BNK/NUC7i5BNB, BIOS BNKBL357.86A.0052.2017.0918.1346 09/18/2017
[   48.478047] Workqueue: i915 __i915_gem_free_work [i915]
[   48.478075] Call Trace:
[   48.478111]  dump_stack+0x5b/0x90
[   48.478137]  print_address_description+0x67/0x237
[   48.478178]  ? __cached_rbnode_delete_update+0x68/0x110
[   48.478212]  __kasan_report.cold.3+0x1c/0x38
[   48.478240]  ? __cached_rbnode_delete_update+0x68/0x110
[   48.478280]  ? __cached_rbnode_delete_update+0x68/0x110
[   48.478308]  __cached_rbnode_delete_update+0x68/0x110
[   48.478344]  private_free_iova+0x2b/0x60
[   48.478378]  iova_magazine_free_pfns+0x46/0xa0
[   48.478403]  free_iova_fast+0x277/0x340
[   48.478443]  fq_ring_free+0x15a/0x1a0
[   48.478473]  queue_iova+0x19c/0x1f0
[   48.478597]  cleanup_page_dma.isra.64+0x62/0xb0 [i915]
[   48.478712]  __gen8_ppgtt_cleanup+0x63/0x80 [i915]
[   48.478826]  __gen8_ppgtt_cleanup+0x42/0x80 [i915]
[   48.478940]  __gen8_ppgtt_clear+0x433/0x4b0 [i915]
[   48.479053]  __gen8_ppgtt_clear+0x462/0x4b0 [i915]
[   48.479081]  ? __sg_free_table+0x9e/0xf0
[   48.479116]  ? kfree+0x7f/0x150
[   48.479234]  i915_vma_unbind+0x1e2/0x240 [i915]
[   48.479352]  i915_vma_destroy+0x3a/0x280 [i915]
[   48.479465]  __i915_gem_free_objects+0xf0/0x2d0 [i915]
[   48.479579]  __i915_gem_free_work+0x41/0xa0 [i915]
[   48.479607]  process_one_work+0x495/0x710
[   48.479642]  worker_thread+0x4c7/0x6f0
[   48.479687]  ? process_one_work+0x710/0x710
[   48.479724]  kthread+0x1b2/0x1d0
[   48.479774]  ? kthread_create_worker_on_cpu+0xa0/0xa0
[   48.479820]  ret_from_fork+0x1f/0x30
[   48.479864]
[   48.479907] Allocated by task 631:
[   48.479944]  save_stack+0x19/0x80
[   48.479994]  __kasan_kmalloc.constprop.6+0xc1/0xd0
[   48.480038]  kmem_cache_alloc+0x91/0xf0
[   48.480082]  alloc_iova+0x2b/0x1e0
[   48.480125]  alloc_iova_fast+0x58/0x376
[   48.480166]  intel_alloc_iova+0x90/0xc0
[   48.480214]  intel_map_sg+0xde/0x1f0
[   48.480343]  i915_gem_gtt_prepare_pages+0xb8/0x170 [i915]
[   48.480465]  huge_get_pages+0x232/0x2b0 [i915]
[   48.480590]  ____i915_gem_object_get_pages+0x40/0xb0 [i915]
[   48.480712]  __i915_gem_object_get_pages+0x90/0xa0 [i915]
[   48.480834]  i915_gem_object_prepare_write+0x2d6/0x330 [i915]
[   48.480955]  create_test_object.isra.54+0x1a9/0x3e0 [i915]
[   48.481075]  igt_shared_ctx_exec+0x365/0x3c0 [i915]
[   48.481210]  __i915_subtests.cold.4+0x30/0x92 [i915]
[   48.481341]  __run_selftests.cold.3+0xa9/0x119 [i915]
[   48.481466]  i915_live_selftests+0x3c/0x70 [i915]
[   48.481583]  i915_pci_probe+0xe7/0x220 [i915]
[   48.481620]  pci_device_probe+0xe0/0x180
[   48.481665]  really_probe+0x163/0x4e0
[   48.481710]  device_driver_attach+0x85/0x90
[   48.481750]  __driver_attach+0xa5/0x180
[   48.481796]  bus_for_each_dev+0xda/0x130
[   48.481831]  bus_add_driver+0x205/0x2e0
[   48.481882]  driver_register+0xca/0x140
[   48.481927]  do_one_initcall+0x6c/0x1af
[   48.481970]  do_init_module+0x106/0x350
[   48.482010]  load_module+0x3d2c/0x3ea0
[   48.482058]  __do_sys_finit_module+0x110/0x180
[   48.482102]  do_syscall_64+0x62/0x1f0
[   48.482147]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   48.482190]
[   48.482224] Freed by task 37:
[   48.482273]  save_stack+0x19/0x80
[   48.482318]  __kasan_slab_free+0x12e/0x180
[   48.482363]  kmem_cache_free+0x70/0x140
[   48.482406]  __free_iova+0x1d/0x30
[   48.482445]  fq_ring_free+0x15a/0x1a0
[   48.482490]  queue_iova+0x19c/0x1f0
[   48.482624]  cleanup_page_dma.isra.64+0x62/0xb0 [i915]
[   48.482749]  __gen8_ppgtt_cleanup+0x63/0x80 [i915]
[   48.482873]  __gen8_ppgtt_cleanup+0x42/0x80 [i915]
[   48.482999]  __gen8_ppgtt_clear+0x433/0x4b0 [i915]
[   48.483123]  __gen8_ppgtt_clear+0x462/0x4b0 [i915]
[   48.483250]  i915_vma_unbind+0x1e2/0x240 [i915]
[   48.483378]  i915_vma_destroy+0x3a/0x280 [i915]
[   48.483500]  __i915_gem_free_objects+0xf0/0x2d0 [i915]
[   48.483622]  __i915_gem_free_work+0x41/0xa0 [i915]
[   48.483659]  process_one_work+0x495/0x710
[   48.483704]  worker_thread+0x4c7/0x6f0
[   48.483748]  kthread+0x1b2/0x1d0
[   48.483787]  ret_from_fork+0x1f/0x30
[   48.483831]
[   48.483868] The buggy address belongs to the object at ffff88870fc19000
[   48.483868]  which belongs to the cache iommu_iova of size 40
[   48.483920] The buggy address is located 32 bytes inside of
[   48.483920]  40-byte region [ffff88870fc19000, ffff88870fc19028)
[   48.483964] The buggy address belongs to the page:
[   48.484006] page:ffffea001c3f0600 refcount:1 mapcount:0 mapping:ffff8888181a91c0 index:0x0 compound_mapcount: 0
[   48.484045] flags: 0x8000000000010200(slab|head)
[   48.484096] raw: 8000000000010200 ffffea001c421a08 ffffea001c447e88 ffff8888181a91c0
[   48.484141] raw: 0000000000000000 0000000000120012 00000001ffffffff 0000000000000000
[   48.484188] page dumped because: kasan: bad access detected
[   48.484230]
[   48.484265] Memory state around the buggy address:
[   48.484314]  ffff88870fc18f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   48.484361]  ffff88870fc18f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   48.484406] >ffff88870fc19000: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
[   48.484451]                                ^
[   48.484494]  ffff88870fc19080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   48.484530]  ffff88870fc19100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108602
Fixes: e60aa7b538 ("iommu/iova: Extend rbtree node caching")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: <stable@vger.kernel.org> # v4.15+
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 17:50:49 +02:00
Dmitry Safonov
3ee9eca760 iommu/vt-d: Check if domain->pgd was allocated
There is a couple of places where on domain_init() failure domain_exit()
is called. While currently domain_init() can fail only if
alloc_pgtable_page() has failed.

Make domain_exit() check if domain->pgd present, before calling
domain_unmap(), as it theoretically should crash on clearing pte entries
in dma_pte_clear_level().

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: iommu@lists.linux-foundation.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 17:43:06 +02:00
Dmitry Safonov
effa467870 iommu/vt-d: Don't queue_iova() if there is no flush queue
Intel VT-d driver was reworked to use common deferred flushing
implementation. Previously there was one global per-cpu flush queue,
afterwards - one per domain.

Before deferring a flush, the queue should be allocated and initialized.

Currently only domains with IOMMU_DOMAIN_DMA type initialize their flush
queue. It's probably worth to init it for static or unmanaged domains
too, but it may be arguable - I'm leaving it to iommu folks.

Prevent queuing an iova flush if the domain doesn't have a queue.
The defensive check seems to be worth to keep even if queue would be
initialized for all kinds of domains. And is easy backportable.

On 4.19.43 stable kernel it has a user-visible effect: previously for
devices in si domain there were crashes, on sata devices:

 BUG: spinlock bad magic on CPU#6, swapper/0/1
  lock: 0xffff88844f582008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
 CPU: 6 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #1
 Call Trace:
  <IRQ>
  dump_stack+0x61/0x7e
  spin_bug+0x9d/0xa3
  do_raw_spin_lock+0x22/0x8e
  _raw_spin_lock_irqsave+0x32/0x3a
  queue_iova+0x45/0x115
  intel_unmap+0x107/0x113
  intel_unmap_sg+0x6b/0x76
  __ata_qc_complete+0x7f/0x103
  ata_qc_complete+0x9b/0x26a
  ata_qc_complete_multiple+0xd0/0xe3
  ahci_handle_port_interrupt+0x3ee/0x48a
  ahci_handle_port_intr+0x73/0xa9
  ahci_single_level_irq_intr+0x40/0x60
  __handle_irq_event_percpu+0x7f/0x19a
  handle_irq_event_percpu+0x32/0x72
  handle_irq_event+0x38/0x56
  handle_edge_irq+0x102/0x121
  handle_irq+0x147/0x15c
  do_IRQ+0x66/0xf2
  common_interrupt+0xf/0xf
 RIP: 0010:__do_softirq+0x8c/0x2df

The same for usb devices that use ehci-pci:
 BUG: spinlock bad magic on CPU#0, swapper/0/1
  lock: 0xffff88844f402008, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.43 #4
 Call Trace:
  <IRQ>
  dump_stack+0x61/0x7e
  spin_bug+0x9d/0xa3
  do_raw_spin_lock+0x22/0x8e
  _raw_spin_lock_irqsave+0x32/0x3a
  queue_iova+0x77/0x145
  intel_unmap+0x107/0x113
  intel_unmap_page+0xe/0x10
  usb_hcd_unmap_urb_setup_for_dma+0x53/0x9d
  usb_hcd_unmap_urb_for_dma+0x17/0x100
  unmap_urb_for_dma+0x22/0x24
  __usb_hcd_giveback_urb+0x51/0xc3
  usb_giveback_urb_bh+0x97/0xde
  tasklet_action_common.isra.4+0x5f/0xa1
  tasklet_action+0x2d/0x30
  __do_softirq+0x138/0x2df
  irq_exit+0x7d/0x8b
  smp_apic_timer_interrupt+0x10f/0x151
  apic_timer_interrupt+0xf/0x20
  </IRQ>
 RIP: 0010:_raw_spin_unlock_irqrestore+0x17/0x39

Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: <stable@vger.kernel.org> # 4.14+
Fixes: 13cf017446 ("iommu/vt-d: Make use of iova deferred flushing")
Signed-off-by: Dmitry Safonov <dima@arista.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 17:43:06 +02:00
Lu Baolu
557529494d iommu/vt-d: Avoid duplicated pci dma alias consideration
As we have abandoned the home-made lazy domain allocation
and delegated the DMA domain life cycle up to the default
domain mechanism defined in the generic iommu layer, we
needn't consider pci alias anymore when mapping/unmapping
the context entries. Without this fix, we see kernel NULL
pointer dereference during pci device hot-plug test.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Fixes: fa954e6831 ("iommu/vt-d: Delegate the dma domain to upper layer")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reported-and-tested-by: Xu Pengfei <pengfei.xu@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 17:16:24 +02:00
Joerg Roedel
301e7ee1de Revert "iommu/vt-d: Consolidate domain_init() to avoid duplication"
This reverts commit 123b2ffc37.

This commit reportedly caused boot failures on some systems
and needs to be reverted for now.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-22 16:21:17 +02:00
Qian Cai
8cf6650421 iommu/amd: fix a crash in iova_magazine_free_pfns
The commit b3aa14f022 ("iommu: remove the mapping_error dma_map_ops
method") incorrectly changed the checking from dma_ops_alloc_iova() in
map_sg() causes a crash under memory pressure as dma_ops_alloc_iova()
never return DMA_MAPPING_ERROR on failure but 0, so the error handling
is all wrong.

   kernel BUG at drivers/iommu/iova.c:801!
    Workqueue: kblockd blk_mq_run_work_fn
    RIP: 0010:iova_magazine_free_pfns+0x7d/0xc0
    Call Trace:
     free_cpu_cached_iovas+0xbd/0x150
     alloc_iova_fast+0x8c/0xba
     dma_ops_alloc_iova.isra.6+0x65/0xa0
     map_sg+0x8c/0x2a0
     scsi_dma_map+0xc6/0x160
     pqi_aio_submit_io+0x1f6/0x440 [smartpqi]
     pqi_scsi_queue_command+0x90c/0xdd0 [smartpqi]
     scsi_queue_rq+0x79c/0x1200
     blk_mq_dispatch_rq_list+0x4dc/0xb70
     blk_mq_sched_dispatch_requests+0x249/0x310
     __blk_mq_run_hw_queue+0x128/0x200
     blk_mq_run_work_fn+0x27/0x30
     process_one_work+0x522/0xa10
     worker_thread+0x63/0x5b0
     kthread+0x1d2/0x1f0
     ret_from_fork+0x22/0x40

Fixes: b3aa14f022 ("iommu: remove the mapping_error dma_map_ops method")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-21 09:57:13 -07:00
Linus Torvalds
3a1d5384b7 virtio, vhost: fixes, features, performance
new iommu device
 vhost guest memory access using vmap (just meta-data for now)
 minor fixes
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
 
 Note: due to code driver changes the driver-core tree, the following
 patch is needed when merging tree with commit 92ce7e83b4
 ("driver_find_device: Unify the match function with
 class_find_device()") in the driver-core tree:
 
 From: Nathan Chancellor <natechancellor@gmail.com>
 Subject: [PATCH] iommu/virtio: Constify data parameter in viommu_match_node
 
 After commit 92ce7e83b4 ("driver_find_device: Unify the match
 function with class_find_device()") in the driver-core tree.
 
 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
 
 ---
  drivers/iommu/virtio-iommu.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
 
 diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
 index 4620dd221ffd..433f4d2ee956 100644
 --- a/drivers/iommu/virtio-iommu.c
 +++ b/drivers/iommu/virtio-iommu.c
 @@ -839,7 +839,7 @@ static void viommu_put_resv_regions(struct device *dev, struct list_head *head)
  static struct iommu_ops viommu_ops;
  static struct virtio_driver virtio_iommu_drv;
 
 -static int viommu_match_node(struct device *dev, void *data)
 +static int viommu_match_node(struct device *dev, const void *data)
  {
  	return dev->parent->fwnode == data;
  }
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio, vhost updates from Michael Tsirkin:
 "Fixes, features, performance:

   - new iommu device

   - vhost guest memory access using vmap (just meta-data for now)

   - minor fixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-mmio: add error check for platform_get_irq
  scsi: virtio_scsi: Use struct_size() helper
  iommu/virtio: Add event queue
  iommu/virtio: Add probe request
  iommu: Add virtio-iommu driver
  PCI: OF: Initialize dev->fwnode appropriately
  of: Allow the iommu-map property to omit untranslated devices
  dt-bindings: virtio: Add virtio-pci-iommu node
  dt-bindings: virtio-mmio: Add IOMMU description
  vhost: fix clang build warning
  vhost: access vq metadata through kernel virtual address
  vhost: factor out setting vring addr and num
  vhost: introduce helpers to get the size of metadata area
  vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()
  vhost: fine grain userspace memory accessors
  vhost: generalize adding used elem
2019-07-17 11:26:09 -07:00
Linus Torvalds
9e3a25dc99 dma-mapping updates for Linux 5.3
- move the USB special case that bounced DMA through a device
    bar into the USB code instead of handling it in the common
    DMA code (Laurentiu Tudor and Fredrik Noring)
  - don't dip into the global CMA pool for single page allocations
    (Nicolin Chen)
  - fix a crash when allocating memory for the atomic pool failed
    during boot (Florian Fainelli)
  - move support for MIPS-style uncached segments to the common
    code and use that for MIPS and nios2 (me)
  - make support for DMA_ATTR_NON_CONSISTENT and
    DMA_ATTR_NO_KERNEL_MAPPING generic (me)
  - convert nds32 to the generic remapping allocator (me)
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Merge tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - move the USB special case that bounced DMA through a device bar into
   the USB code instead of handling it in the common DMA code (Laurentiu
   Tudor and Fredrik Noring)

 - don't dip into the global CMA pool for single page allocations
   (Nicolin Chen)

 - fix a crash when allocating memory for the atomic pool failed during
   boot (Florian Fainelli)

 - move support for MIPS-style uncached segments to the common code and
   use that for MIPS and nios2 (me)

 - make support for DMA_ATTR_NON_CONSISTENT and
   DMA_ATTR_NO_KERNEL_MAPPING generic (me)

 - convert nds32 to the generic remapping allocator (me)

* tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping: (29 commits)
  dma-mapping: mark dma_alloc_need_uncached as __always_inline
  MIPS: only select ARCH_HAS_UNCACHED_SEGMENT for non-coherent platforms
  usb: host: Fix excessive alignment restriction for local memory allocations
  lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocators
  nios2: use the generic uncached segment support in dma-direct
  nds32: use the generic remapping allocator for coherent DMA allocations
  arc: use the generic remapping allocator for coherent DMA allocations
  dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code
  dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code
  dma-mapping: add a dma_alloc_need_uncached helper
  openrisc: remove the partial DMA_ATTR_NON_CONSISTENT support
  arc: remove the partial DMA_ATTR_NON_CONSISTENT support
  arm-nommu: remove the partial DMA_ATTR_NON_CONSISTENT support
  ARM: dma-mapping: allow larger DMA mask than supported
  dma-mapping: truncate dma masks to what dma_addr_t can hold
  iommu/dma: Apply dma_{alloc,free}_contiguous functions
  dma-remap: Avoid de-referencing NULL atomic_pool
  MIPS: use the generic uncached segment support in dma-direct
  dma-direct: provide generic support for uncached kernel segments
  au1100fb: fix DMA API abuse
  ...
2019-07-12 15:13:55 -07:00
Linus Torvalds
f632a8170a Driver Core and debugfs changes for 5.3-rc1
Here is the "big" driver core and debugfs changes for 5.3-rc1
 
 It's a lot of different patches, all across the tree due to some api
 changes and lots of debugfs cleanups.  Because of this, there is going
 to be some merge issues with your tree at the moment, I'll follow up
 with the expected resolutions to make it easier for you.
 
 Other than the debugfs cleanups, in this set of changes we have:
 	- bus iteration function cleanups (will cause build warnings
 	  with s390 and coresight drivers in your tree)
 	- scripts/get_abi.pl tool to display and parse Documentation/ABI
 	  entries in a simple way
 	- cleanups to Documenatation/ABI/ entries to make them parse
 	  easier due to typos and other minor things
 	- default_attrs use for some ktype users
 	- driver model documentation file conversions to .rst
 	- compressed firmware file loading
 	- deferred probe fixes
 
 All of these have been in linux-next for a while, with a bunch of merge
 issues that Stephen has been patient with me for.  Other than the merge
 issues, functionality is working properly in linux-next :)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...
2019-07-12 12:24:03 -07:00
Joerg Roedel
d95c388586 Merge branches 'x86/vt-d', 'x86/amd', 'arm/smmu', 'arm/omap', 'generic-dma-ops' and 'core' into next 2019-07-04 17:26:48 +02:00
Greg Kroah-Hartman
9378bfeaaf iommu/omap: No need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Joerg Roedel <joro@8bytes.org>
Cc: iommu@lists.linux-foundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-04 17:26:18 +02:00
Jean-Philippe Brucker
8dd8f005bd iommu/arm-smmu-v3: Invalidate ATC when detaching a device
We make the invalid assumption in arm_smmu_detach_dev() that the ATC is
clear after calling pci_disable_ats(). For one thing, only enabling the
PCIe ATS capability constitutes an implicit invalidation event, so the
comment was wrong. More importantly, the ATS capability isn't necessarily
disabled by pci_disable_ats() in a PF, if the associated VFs have ATS
enabled. Explicitly invalidate all ATC entries in arm_smmu_detach_dev().
The endpoint cannot form new ATC entries because STE.EATS is clear.

Fixes: 9ce27afc08 ("iommu/arm-smmu-v3: Add support for PCI ATS")
Reported-by: Manoj Kumar <Manoj.Kumar3@arm.com>
Reported-by: Robin Murphy <Robin.Murphy@arm.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-04 10:03:27 +02:00
Will Deacon
900a85ca43 iommu/arm-smmu-v3: Fix compilation when CONFIG_CMA=n
When compiling a kernel without support for CMA, CONFIG_CMA_ALIGNMENT
is not defined which results in the following build failure:

In file included from ./include/linux/list.h:9:0
                 from ./include/linux/kobject.h:19,
                 from ./include/linux/of.h:17
                 from ./include/linux/irqdomain.h:35,
                 from ./include/linux/acpi.h:13,
                 from drivers/iommu/arm-smmu-v3.c:12:
drivers/iommu/arm-smmu-v3.c: In function ‘arm_smmu_device_hw_probe’:
drivers/iommu/arm-smmu-v3.c:194:40: error: ‘CONFIG_CMA_ALIGNMENT’ undeclared (first use in this function)
 #define Q_MAX_SZ_SHIFT   (PAGE_SHIFT + CONFIG_CMA_ALIGNMENT)

Fix the breakage by capping the maximum queue size based on MAX_ORDER
when CMA is not enabled.

Reported-by: Zhangshaokun <zhangshaokun@hisilicon.com>
Signed-off-by: Will Deacon <will@kernel.org>
Tested-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-02 17:13:39 +02:00
Joerg Roedel
3430abd6f4 Merge branch 'arm/renesas' into arm/smmu 2019-07-01 14:41:24 +02:00
Jacob Pan
0bcfa628f8 iommu/vt-d: Cleanup unused variable
Linux IRQ number virq is not used in IRTE allocation. Remove it.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-01 14:24:01 +02:00
Tom Murphy
5cd3f2e98c iommu/amd: Flush not present cache in iommu_map_page
check if there is a not-present cache present and flush it if there is.

Signed-off-by: Tom Murphy <murphyt7@tcd.ie>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-01 14:15:47 +02:00
Kevin Mitchell
5c90501a72 iommu/amd: Only free resources once on init error
When amd_iommu=off was specified on the command line, free_X_resources
functions were called immediately after early_amd_iommu_init. They were
then called again when amd_iommu_init also failed (as expected).

Instead, call them only once: at the end of state_next() whenever
there's an error. These functions should be safe to call any time and
any number of times. However, since state_next is never called again in
an error state, the cleanup will only ever be run once.

This also ensures that cleanup code is run as soon as possible after an
error is detected rather than waiting for amd_iommu_init() to be called.

Signed-off-by: Kevin Mitchell <kevmitch@arista.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-01 14:03:07 +02:00
Kevin Mitchell
bf4bff46ea iommu/amd: Move gart fallback to amd_iommu_init
The fallback to the GART driver in the case amd_iommu doesn't work was
executed in a function called free_iommu_resources, which didn't really
make sense. This was even being called twice if amd_iommu=off was
specified on the command line.

The only complication is that it needs to be verified that amd_iommu has
fully relinquished control by calling free_iommu_resources and emptying
the amd_iommu_list.

Signed-off-by: Kevin Mitchell <kevmitch@arista.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-01 14:03:07 +02:00
Kevin Mitchell
3ddbe913e5 iommu/amd: Make iommu_disable safer
Make it safe to call iommu_disable during early init error conditions
before mmio_base is set, but after the struct amd_iommu has been added
to the amd_iommu_list. For example, this happens if firmware fails to
fill in mmio_phys in the ACPI table leading to a NULL pointer
dereference in iommu_feature_disable.

Fixes: 2c0ae1720c ('iommu/amd: Convert iommu initialization to state machine')
Signed-off-by: Kevin Mitchell <kevmitch@arista.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-07-01 14:02:33 +02:00
Joerg Roedel
39debdc1d7 Merge branch 'for-joerg/arm-smmu/updates' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into arm/smmu 2019-07-01 13:44:41 +02:00
Bjorn Andersson
9e6ea59f3f iommu/io-pgtable: Support non-coherent page tables
Describe the memory related to page table walks as non-cacheable for
iommu instances that are not DMA coherent.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[will: Use cfg->coherent_walk, fix arm-v7s, ensure outer-shareable for NC]
Signed-off-by: Will Deacon <will@kernel.org>
2019-06-25 13:26:47 +01:00
Will Deacon
4f41845b34 iommu/io-pgtable: Replace IO_PGTABLE_QUIRK_NO_DMA with specific flag
IO_PGTABLE_QUIRK_NO_DMA is a bit of a misnomer, since it's really just
an indication of whether or not the page-table walker for the IOMMU is
coherent with the CPU caches. Since cache coherency is more than just a
quirk, replace the flag with its own field in the io_pgtable_cfg
structure.

Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
2019-06-25 12:51:25 +01:00
Joerg Roedel
ceedd5f74d Linux 5.2-rc6
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Merge tag 'v5.2-rc6' into generic-dma-ops

Linux 5.2-rc6
2019-06-24 10:23:16 +02:00
Suzuki K Poulose
92ce7e83b4 driver_find_device: Unify the match function with class_find_device()
The driver_find_device() accepts a match function pointer to
filter the devices for lookup, similar to bus/class_find_device().
However, there is a minor difference in the prototype for the
match parameter for driver_find_device() with the now unified
version accepted by {bus/class}_find_device(), where it doesn't
accept a "const" qualifier for the data argument. This prevents
us from reusing the generic match functions for driver_find_device().

For this reason, change the prototype of the driver_find_device() to
make the "match" parameter in line with {bus/class}_find_device()
and adjust its callers to use the const qualifier. Also, we could
now promote the "data" parameter to const as we pass it down
as a const parameter to the match functions.

Cc: Corey Minyard <minyard@acm.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Sebastian Ott <sebott@linux.ibm.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Nehal Shah <nehal-bakulchandra.shah@amd.com>
Cc: Shyam Sundar S K <shyam-sundar.s-k@amd.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-24 05:22:31 +02:00
Linus Torvalds
6698a71a1e IOMMU Fix for v5.2-rc5:
- Revert a commit from the previous pile of fixes which causes
 	  new lockdep splats. It is better to revert it for now and work
 	  on a better and more well tested fix.
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Merge tag 'iommu-fix-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fix from Joerg Roedel:
 "Revert a commit from the previous pile of fixes which causes new
  lockdep splats. It is better to revert it for now and work on a better
  and more well tested fix"

* tag 'iommu-fix-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  Revert "iommu/vt-d: Fix lock inversion between iommu->lock and device_domain_lock"
2019-06-22 14:08:47 -07:00
Peter Xu
0aafc8ae66 Revert "iommu/vt-d: Fix lock inversion between iommu->lock and device_domain_lock"
This reverts commit 7560cc3ca7.

With 5.2.0-rc5 I can easily trigger this with lockdep and iommu=pt:

    ======================================================
    WARNING: possible circular locking dependency detected
    5.2.0-rc5 #78 Not tainted
    ------------------------------------------------------
    swapper/0/1 is trying to acquire lock:
    00000000ea2b3beb (&(&iommu->lock)->rlock){+.+.}, at: domain_context_mapping_one+0xa5/0x4e0
    but task is already holding lock:
    00000000a681907b (device_domain_lock){....}, at: domain_context_mapping_one+0x8d/0x4e0
    which lock already depends on the new lock.
    the existing dependency chain (in reverse order) is:
    -> #1 (device_domain_lock){....}:
           _raw_spin_lock_irqsave+0x3c/0x50
           dmar_insert_one_dev_info+0xbb/0x510
           domain_add_dev_info+0x50/0x90
           dev_prepare_static_identity_mapping+0x30/0x68
           intel_iommu_init+0xddd/0x1422
           pci_iommu_init+0x16/0x3f
           do_one_initcall+0x5d/0x2b4
           kernel_init_freeable+0x218/0x2c1
           kernel_init+0xa/0x100
           ret_from_fork+0x3a/0x50
    -> #0 (&(&iommu->lock)->rlock){+.+.}:
           lock_acquire+0x9e/0x170
           _raw_spin_lock+0x25/0x30
           domain_context_mapping_one+0xa5/0x4e0
           pci_for_each_dma_alias+0x30/0x140
           dmar_insert_one_dev_info+0x3b2/0x510
           domain_add_dev_info+0x50/0x90
           dev_prepare_static_identity_mapping+0x30/0x68
           intel_iommu_init+0xddd/0x1422
           pci_iommu_init+0x16/0x3f
           do_one_initcall+0x5d/0x2b4
           kernel_init_freeable+0x218/0x2c1
           kernel_init+0xa/0x100
           ret_from_fork+0x3a/0x50

    other info that might help us debug this:
     Possible unsafe locking scenario:
           CPU0                    CPU1
           ----                    ----
      lock(device_domain_lock);
                                   lock(&(&iommu->lock)->rlock);
                                   lock(device_domain_lock);
      lock(&(&iommu->lock)->rlock);

     *** DEADLOCK ***
    2 locks held by swapper/0/1:
     #0: 00000000033eb13d (dmar_global_lock){++++}, at: intel_iommu_init+0x1e0/0x1422
     #1: 00000000a681907b (device_domain_lock){....}, at: domain_context_mapping_one+0x8d/0x4e0

    stack backtrace:
    CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc5 #78
    Hardware name: LENOVO 20KGS35G01/20KGS35G01, BIOS N23ET50W (1.25 ) 06/25/2018
    Call Trace:
     dump_stack+0x85/0xc0
     print_circular_bug.cold.57+0x15c/0x195
     __lock_acquire+0x152a/0x1710
     lock_acquire+0x9e/0x170
     ? domain_context_mapping_one+0xa5/0x4e0
     _raw_spin_lock+0x25/0x30
     ? domain_context_mapping_one+0xa5/0x4e0
     domain_context_mapping_one+0xa5/0x4e0
     ? domain_context_mapping_one+0x4e0/0x4e0
     pci_for_each_dma_alias+0x30/0x140
     dmar_insert_one_dev_info+0x3b2/0x510
     domain_add_dev_info+0x50/0x90
     dev_prepare_static_identity_mapping+0x30/0x68
     intel_iommu_init+0xddd/0x1422
     ? printk+0x58/0x6f
     ? lockdep_hardirqs_on+0xf0/0x180
     ? do_early_param+0x8e/0x8e
     ? e820__memblock_setup+0x63/0x63
     pci_iommu_init+0x16/0x3f
     do_one_initcall+0x5d/0x2b4
     ? do_early_param+0x8e/0x8e
     ? rcu_read_lock_sched_held+0x55/0x60
     ? do_early_param+0x8e/0x8e
     kernel_init_freeable+0x218/0x2c1
     ? rest_init+0x230/0x230
     kernel_init+0xa/0x100
     ret_from_fork+0x3a/0x50

domain_context_mapping_one() is taking device_domain_lock first then
iommu lock, while dmar_insert_one_dev_info() is doing the reverse.

That should be introduced by commit:

7560cc3ca7 ("iommu/vt-d: Fix lock inversion between iommu->lock and
              device_domain_lock", 2019-05-27)

So far I still cannot figure out how the previous deadlock was
triggered (I cannot find iommu lock taken before calling of
iommu_flush_dev_iotlb()), however I'm pretty sure that that change
should be incomplete at least because it does not fix all the places
so we're still taking the locks in different orders, while reverting
that commit is very clean to me so far that we should always take
device_domain_lock first then the iommu lock.

We can continue to try to find the real culprit mentioned in
7560cc3ca7, but for now I think we should revert it to fix current
breakage.

CC: Joerg Roedel <joro@8bytes.org>
CC: Lu Baolu <baolu.lu@linux.intel.com>
CC: dave.jiang@intel.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-22 21:19:58 +02:00
Thomas Gleixner
d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Thomas Gleixner
caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Vivek Gautam
90ec7a76cc iommu/io-pgtable-arm: Add support to use system cache
Few Qualcomm platforms such as, sdm845 have an additional outer
cache called as System cache, aka. Last level cache (LLC) that
allows non-coherent devices to upgrade to using caching.
This cache sits right before the DDR, and is tightly coupled
with the memory controller. The clients using this cache request
their slices from this system cache, make it active, and can then
start using it.

There is a fundamental assumption that non-coherent devices can't
access caches. This change adds an exception where they *can* use
some level of cache despite still being non-coherent overall.
The coherent devices that use cacheable memory, and CPU make use of
this system cache by default.

Looking at memory types, we have following -
a) Normal uncached :- MAIR 0x44, inner non-cacheable,
                      outer non-cacheable;
b) Normal cached :-   MAIR 0xff, inner read write-back non-transient,
                      outer read write-back non-transient;
                      attribute setting for coherenet I/O devices.
and, for non-coherent i/o devices that can allocate in system cache
another type gets added -
c) Normal sys-cached :- MAIR 0xf4, inner non-cacheable,
                        outer read write-back non-transient

Coherent I/O devices use system cache by marking the memory as
normal cached.
Non-coherent I/O devices should mark the memory as normal
sys-cached in page tables to use system cache.

Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-06-18 19:27:37 +01:00
Will Deacon
d25f6ead16 iommu/arm-smmu-v3: Increase maximum size of queues
We've been artificially limiting the size of our queues to 4k so that we
don't end up allocating huge amounts of physically-contiguous memory at
probe time. However, 4k is only enough for 256 commands in the command
queue, so instead let's try to allocate the largest queue that the SMMU
supports, retrying with a smaller size if the allocation fails.

The caveat here is that we have to limit our upper bound based on
CONFIG_CMA_ALIGNMENT to ensure that our queue allocations remain
natually aligned, which is required by the SMMU architecture.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-06-18 18:11:20 +01:00
Qian Cai
af88ec3962 iommu/vt-d: Silence a variable set but not used
The commit "iommu/vt-d: Probe DMA-capable ACPI name space devices"
introduced a compilation warning due to the "iommu" variable in
for_each_active_iommu() but never used the for each element, i.e,
"drhd->iommu".

drivers/iommu/intel-iommu.c: In function 'probe_acpi_namespace_devices':
drivers/iommu/intel-iommu.c:4639:22: warning: variable 'iommu' set but
not used [-Wunused-but-set-variable]
  struct intel_iommu *iommu;

Silence the warning the same way as in the commit d3ed71e5cc
("drivers/iommu/intel-iommu.c: fix variable 'iommu' set but not used")

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-18 17:31:46 +02:00
Qian Cai
42db7c6a40 iommu/vt-d: Remove an unused variable "length"
The linux-next commit "iommu/vt-d: Duplicate iommu_resv_region objects
per device list" [1] left out an unused variable,

drivers/iommu/intel-iommu.c: In function 'dmar_parse_one_rmrr':
drivers/iommu/intel-iommu.c:4014:9: warning: variable 'length' set but
not used [-Wunused-but-set-variable]

[1] https://lore.kernel.org/patchwork/patch/1083073/

Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-18 17:30:06 +02:00