linux-toradex.git/drivers/iommu, branch v4.4.78

iommu/amd: Fix incorrect error handling in amd_iommu_bind_pasid()

2017-07-05T12:37:22+00:00

commit 73dbd4a4230216b6a5540a362edceae0c9b4876b upstream.

In function amd_iommu_bind_pasid(), the control flow jumps
to label out_free when pasid_state->mm and mm is NULL. And
mmput(mm) is called.  In function mmput(mm), mm is
referenced without validation. This will result in a NULL
dereference bug. This patch fixes the bug.

Signed-off-by: Pan Bian 
Fixes: f0aac63b873b ('iommu/amd: Don't hold a reference to mm_struct')
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu: Handle default domain attach failure

2017-07-05T12:37:22+00:00

commit 797a8b4d768c58caac58ee3e8cb36a164d1b7751 upstream.

We wouldn't normally expect ops->attach_dev() to fail, but on IOMMUs
with limited hardware resources, or generally misconfigured systems,
it is certainly possible. We report failure correctly from the external
iommu_attach_device() interface, but do not do so in iommu_group_add()
when attaching to the default domain. The result of failure there is
that the device, group and domain all get left in a broken,
part-configured state which leads to weird errors and misbehaviour down
the line when IOMMU API calls sort-of-but-don't-quite work.

Check the return value of __iommu_attach_device() on the default domain,
and refactor the error handling paths to cope with its failure and clean
up correctly in such cases.

Fixes: e39cb8a3aa98 ("iommu: Make sure a device is always attached to a domain")
Reported-by: Punit Agrawal 
Signed-off-by: Robin Murphy 
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/vt-d: Don't over-free page table directories

2017-07-05T12:37:22+00:00

commit f7116e115acdd74bc75a4daf6492b11d43505125 upstream.

dma_pte_free_level() recurses down the IOMMU page tables and frees
directory pages that are entirely contained in the given PFN range.
Unfortunately, it incorrectly calculates the starting address covered
by the PTE under consideration, which can lead to it clearing an entry
that is still in use.

This occurs if we have a scatterlist with an entry that has a length
greater than 1026 MB and is aligned to 2 MB for both the IOMMU and
physical addresses. For example, if __domain_mapping() is asked to map a
two-entry scatterlist with 2 MB and 1028 MB segments to PFN 0xffff80000,
it will ask if dma_pte_free_pagetable() is asked to PFNs from
0xffff80200 to 0xffffc05ff, it will also incorrectly clear the PFNs from
0xffff80000 to 0xffff801ff because of this issue. The current code will
set level_pfn to 0xffff80200, and 0xffff80200-0xffffc01ff fits inside
the range being cleared. Properly setting the level_pfn for the current
level under consideration catches that this PTE is outside of the range
being cleared.

This patch also changes the value passed into dma_pte_free_level() when
it recurses. This only affects the first PTE of the range being cleared,
and is handled by the existing code that ensures we start our cursor no
lower than start_pfn.

This was found when using dma_map_sg() to map large chunks of contiguous
memory, which immediatedly led to faults on the first access of the
erroneously-deleted mappings.

Fixes: 3269ee0bd668 ("intel-iommu: Fix leaks in pagetable freeing")
Reviewed-by: Benjamin Serebrin 
Signed-off-by: David Dillow 
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/vt-d: Flush the IOTLB to get rid of the initial kdump mappings

2017-05-25T12:30:16+00:00

commit f73a7eee900e95404b61408a23a1df5c5811704c upstream.

Ever since commit 091d42e43d ("iommu/vt-d: Copy translation tables from
old kernel") the kdump kernel copies the IOMMU context tables from the
previous kernel. Each device mappings will be destroyed once the driver
for the respective device takes over.

This unfortunately breaks the workflow of mapping and unmapping a new
context to the IOMMU. The mapping function assumes that either:

1) Unmapping did the proper IOMMU flushing and it only ever flush if the
   IOMMU unit supports caching invalid entries.
2) The system just booted and the initialization code took care of
   flushing all IOMMU caches.

This assumption is not true for the kdump kernel since the context
tables have been copied from the previous kernel and translations could
have been cached ever since. So make sure to flush the IOTLB as well
when we destroy these old copied mappings.

Cc: Joerg Roedel 
Cc: David Woodhouse 
Cc: David Woodhouse 
Cc: Anthony Liguori 
Signed-off-by: KarimAllah Ahmed 
Acked-by: David Woodhouse 
Fixes: 091d42e43d ("iommu/vt-d: Copy translation tables from old kernel")
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/vt-d: Fix NULL pointer dereference in device_to_iommu

2017-03-30T07:35:18+00:00

commit 5003ae1e735e6bfe4679d9bed6846274f322e77e upstream.

The function device_to_iommu() in the Intel VT-d driver
lacks a NULL-ptr check, resulting in this oops at boot on
some platforms:

 BUG: unable to handle kernel NULL pointer dereference at 00000000000007ab
 IP: [] device_to_iommu+0x11a/0x1a0
 PGD 0

 [...]

 Call Trace:
   ? find_or_alloc_domain.constprop.29+0x1a/0x300
   ? dw_dma_probe+0x561/0x580 [dw_dmac_core]
   ? __get_valid_domain_for_dev+0x39/0x120
   ? __intel_map_single+0x138/0x180
   ? intel_alloc_coherent+0xb6/0x120
   ? sst_hsw_dsp_init+0x173/0x420 [snd_soc_sst_haswell_pcm]
   ? mutex_lock+0x9/0x30
   ? kernfs_add_one+0xdb/0x130
   ? devres_add+0x19/0x60
   ? hsw_pcm_dev_probe+0x46/0xd0 [snd_soc_sst_haswell_pcm]
   ? platform_drv_probe+0x30/0x90
   ? driver_probe_device+0x1ed/0x2b0
   ? __driver_attach+0x8f/0xa0
   ? driver_probe_device+0x2b0/0x2b0
   ? bus_for_each_dev+0x55/0x90
   ? bus_add_driver+0x110/0x210
   ? 0xffffffffa11ea000
   ? driver_register+0x52/0xc0
   ? 0xffffffffa11ea000
   ? do_one_initcall+0x32/0x130
   ? free_vmap_area_noflush+0x37/0x70
   ? kmem_cache_alloc+0x88/0xd0
   ? do_init_module+0x51/0x1c4
   ? load_module+0x1ee9/0x2430
   ? show_taint+0x20/0x20
   ? kernel_read_file+0xfd/0x190
   ? SyS_finit_module+0xa3/0xb0
   ? do_syscall_64+0x4a/0xb0
   ? entry_SYSCALL64_slow_path+0x25/0x25
 Code: 78 ff ff ff 4d 85 c0 74 ee 49 8b 5a 10 0f b6 9b e0 00 00 00 41 38 98 e0 00 00 00 77 da 0f b6 eb 49 39 a8 88 00 00 00 72 ce eb 8f <41> f6 82 ab 07 00 00 04 0f 85 76 ff ff ff 0f b6 4d 08 88 0e 49
 RIP  [] device_to_iommu+0x11a/0x1a0
  RSP 
 CR2: 00000000000007ab
 ---[ end trace 16f974b6d58d0aad ]---

Add the missing pointer check.

Fixes: 1c387188c60f53b338c20eee32db055dfe022a9b ("iommu/vt-d: Fix IOMMU lookup for SR-IOV Virtual Functions")
Signed-off-by: Koos Vriezen 
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/vt-d: Tylersburg isoch identity map check is done too late.

2017-03-12T05:37:25+00:00

commit 21e722c4c8377b5bc82ad058fed12165af739c1b upstream.

The check to set identity map for tylersburg is done too late. It needs
to be done before the check for identity_map domain is done.

To: Joerg Roedel 
To: David Woodhouse 
Cc: iommu@lists.linux-foundation.org
Cc: linux-kernel@vger.kernel.org
Cc: Ashok Raj 

Fixes: 86080ccc22 ("iommu/vt-d: Allocate si_domain in init_dmars()")
Signed-off-by: Ashok Raj 
Reported-by: Yunhong Jiang 
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/vt-d: Flush old iommu caches for kdump when the device gets context mapped

2017-01-12T10:22:49+00:00

commit aec0e86172a79eb5e44aff1055bb953fe4d47c59 upstream.

We met the DMAR fault both on hpsa P420i and P421 SmartArray controllers
under kdump, it can be steadily reproduced on several different machines,
the dmesg log is like:
HP HPSA Driver (v 3.4.16-0)
hpsa 0000:02:00.0: using doorbell to reset controller
hpsa 0000:02:00.0: board ready after hard reset.
hpsa 0000:02:00.0: Waiting for controller to respond to no-op
DMAR: Setting identity map for device 0000:02:00.0 [0xe8000 - 0xe8fff]
DMAR: Setting identity map for device 0000:02:00.0 [0xf4000 - 0xf4fff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf6e000 - 0xbdf6efff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf6f000 - 0xbdf7efff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf7f000 - 0xbdf82fff]
DMAR: Setting identity map for device 0000:02:00.0 [0xbdf83000 - 0xbdf84fff]
DMAR: DRHD: handling fault status reg 2
DMAR: [DMA Read] Request device [02:00.0] fault addr fffff000 [fault reason 06] PTE Read access is not set
hpsa 0000:02:00.0: controller message 03:00 timed out
hpsa 0000:02:00.0: no-op failed; re-trying

After some debugging, we found that the fault addr is from DMA initiated at
the driver probe stage after reset(not in-flight DMA), and the corresponding
pte entry value is correct, the fault is likely due to the old iommu caches
of the in-flight DMA before it.

Thus we need to flush the old cache after context mapping is setup for the
device, where the device is supposed to finish reset at its driver probe
stage and no in-flight DMA exists hereafter.

I'm not sure if the hardware is responsible for invalidating all the related
caches allocated in the iommu hardware before, but seems not the case for hpsa,
actually many device drivers have problems in properly resetting the hardware.
Anyway flushing (again) by software in kdump kernel when the device gets context
mapped which is a quite infrequent operation does little harm.

With this patch, the problematic machine can survive the kdump tests.

CC: Myron Stowe 
CC: Joseph Szczypek 
CC: Don Brace 
CC: Baoquan He 
CC: Dave Young 
Fixes: 091d42e43d21 ("iommu/vt-d: Copy translation tables from old kernel")
Fixes: dbcd861f252d ("iommu/vt-d: Do not re-use domain-ids from the old kernel")
Fixes: cf484d0e6939 ("iommu/vt-d: Mark copied context entries")
Signed-off-by: Xunlei Pang 
Tested-by: Don Brace 
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/vt-d: Fix pasid table size encoding

2017-01-12T10:22:49+00:00

commit 65ca7f5f7d1cdde6c25172fe6107cd16902f826f upstream.

Different encodings are used to represent supported PASID bits
and number of PASID table entries.
The current code assigns ecap_pss directly to extended context
table entry PTS which is wrong and could result in writing
non-zero bits to the reserved fields. IOMMU fault reason
11 will be reported when reserved bits are nonzero.
This patch converts ecap_pss to extend context entry pts encoding
based on VT-d spec. Chapter 9.4 as follows:
 - number of PASID bits = ecap_pss + 1
 - number of PASID table entries = 2^(pts + 5)
Software assigned limit of pasid_max value is also respected to
match the allocation limitation of PASID table.

cc: Mika Kuoppala 
cc: Ashok Raj 
Signed-off-by: Jacob Pan 
Tested-by: Mika Kuoppala 
Fixes: 2f26e0a9c9860 ('iommu/vt-d: Add basic SVM PASID support')
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/amd: Fix the left value check of cmd buffer

2017-01-12T10:22:49+00:00

commit 432abf68a79332282329286d190e21fe3ac02a31 upstream.

The generic command buffer entry is 128 bits (16 bytes), so the offset
of tail and head pointer should be 16 bytes aligned and increased with
0x10 per command.

When cmd buf is full, head = (tail + 0x10) % CMD_BUFFER_SIZE.

So when left space of cmd buf should be able to store only two
command, we should be issued one COMPLETE_WAIT additionally to wait
all older commands completed. Then the left space should be increased
after IOMMU fetching from cmd buf.

So left check value should be left <= 0x20 (two commands).

Signed-off-by: Huang Rui 
Fixes: ac0ea6e92b222 ('x86/amd-iommu: Improve handling of full command buffer')
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

iommu/amd: Missing error code in amd_iommu_init_device()

2017-01-12T10:22:49+00:00

commit 24c790fbf5d8f54c8c82979db11edea8855b74bf upstream.

We should set "ret" to -EINVAL if iommu_group_get() fails.

Fixes: 55c99a4dc50f ("iommu/amd: Use iommu_attach_group()")
Signed-off-by: Dan Carpenter 
Signed-off-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman