This change adds the dma_resv_usage enum and allows us to specify why a
dma_resv object is queried for its containing fences.
Additional to that a dma_resv_usage_rw() helper function is added to aid
retrieving the fences for a read or write userspace submission.
This is then deployed to the different query functions of the dma_resv
object and all of their users. When the write paratermer was previously
true we now use DMA_RESV_USAGE_WRITE and DMA_RESV_USAGE_READ otherwise.
v2: add KERNEL/OTHER in separate patch
v3: some kerneldoc suggestions by Daniel
v4: some more kerneldoc suggestions by Daniel, fix missing cases lost in
the rebase pointed out by Bas.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220407085946.744568-2-christian.koenig@amd.com
Rename struct dma_buf_map to struct iosys_map and corresponding APIs.
Over time dma-buf-map grew up to more functionality than the one used by
dma-buf: in fact it's just a shim layer to abstract system memory, that
can be accessed via regular load and store, from IO memory that needs to
be acessed via arch helpers.
The idea is to extend this API so it can fulfill other needs, internal
to a single driver. Example: in the i915 driver it's desired to share
the implementation for integrated graphics, which uses mostly system
memory, with discrete graphics, which may need to access IO memory.
The conversion was mostly done with the following semantic patch:
@r1@
@@
- struct dma_buf_map
+ struct iosys_map
@r2@
@@
(
- DMA_BUF_MAP_INIT_VADDR
+ IOSYS_MAP_INIT_VADDR
|
- dma_buf_map_set_vaddr
+ iosys_map_set_vaddr
|
- dma_buf_map_set_vaddr_iomem
+ iosys_map_set_vaddr_iomem
|
- dma_buf_map_is_equal
+ iosys_map_is_equal
|
- dma_buf_map_is_null
+ iosys_map_is_null
|
- dma_buf_map_is_set
+ iosys_map_is_set
|
- dma_buf_map_clear
+ iosys_map_clear
|
- dma_buf_map_memcpy_to
+ iosys_map_memcpy_to
|
- dma_buf_map_incr
+ iosys_map_incr
)
@@
@@
- #include <linux/dma-buf-map.h>
+ #include <linux/iosys-map.h>
Then some files had their includes adjusted and some comments were
update to remove mentions to dma-buf-map.
Since this is not specific to dma-buf anymore, move the documentation to
the "Bus-Independent Device Accesses" section.
v2:
- Squash patches
v3:
- Fix wrong removal of dma-buf.h from MAINTAINERS
- Move documentation from dma-buf.rst to device-io.rst
v4:
- Change documentation title and level
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com
bridge:
- HPD improvments for lt9611uxc
- eDP aux-bus support for ps8640
- LVDS data-mapping selection support
ttm:
- remove huge page functionality (needs reworking)
- fix a race condition during BO eviction
panels:
- add some new panels
fbdev:
- fix double-free
- remove unused scrolling acceleration
- CONFIG_FB dep improvements
locking:
- improve contended locking logging
- naming collision fix
dma-buf:
- add dma_resv_for_each_fence iterator
- fix fence refcounting bug
- name locking fixesA
prime:
- fix object references during mmap
nouveau:
- various code style changes
- refcount fix
- device removal fixes
- protect client list with a mutex
- fix CE0 address calculation
i915:
- DP rates related fixes
- Revert disabling dual eDP that was causing state readout problems
- put the cdclk vtables in const data
- Fix DVO port type for older platforms
- Fix blankscreen by turning DP++ TMDS output buffers on encoder->shutdown
- CCS FBs related fixes
- Fix recursive lock in GuC submission
- Revert guc_id from i915_request tracepoint
- Build fix around dmabuf
amdgpu:
- GPU reset fix
- Aldebaran fix
- Yellow Carp fixes
- DCN2.1 DMCUB fix
- IOMMU regression fix for Picasso
- DSC display fixes
- BPC display calculation fixes
- Other misc display fixes
- Don't allow partial copy from user for DC debugfs
- SRIOV fixes
- GFX9 CSB pin count fix
- Various IP version check fixes
- DP 2.0 fixes
- Limit DCN1 MPO fix to DCN1
amdkfd:
- SVM fixes
- Fix gfx version for renoir
- Reset fixes
udl:
- timeout fix
imx:
- circular locking fix
virtio:
- NULL ptr deref fix
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Merge tag 'drm-next-2021-11-12' of git://anongit.freedesktop.org/drm/drm
Pull more drm updates from Dave Airlie:
"I missed a drm-misc-next pull for the main pull last week. It wasn't
that major and isn't the bulk of this at all. This has a bunch of
fixes all over, a lot for amdgpu and i915.
bridge:
- HPD improvments for lt9611uxc
- eDP aux-bus support for ps8640
- LVDS data-mapping selection support
ttm:
- remove huge page functionality (needs reworking)
- fix a race condition during BO eviction
panels:
- add some new panels
fbdev:
- fix double-free
- remove unused scrolling acceleration
- CONFIG_FB dep improvements
locking:
- improve contended locking logging
- naming collision fix
dma-buf:
- add dma_resv_for_each_fence iterator
- fix fence refcounting bug
- name locking fixesA
prime:
- fix object references during mmap
nouveau:
- various code style changes
- refcount fix
- device removal fixes
- protect client list with a mutex
- fix CE0 address calculation
i915:
- DP rates related fixes
- Revert disabling dual eDP that was causing state readout problems
- put the cdclk vtables in const data
- Fix DVO port type for older platforms
- Fix blankscreen by turning DP++ TMDS output buffers on encoder->shutdown
- CCS FBs related fixes
- Fix recursive lock in GuC submission
- Revert guc_id from i915_request tracepoint
- Build fix around dmabuf
amdgpu:
- GPU reset fix
- Aldebaran fix
- Yellow Carp fixes
- DCN2.1 DMCUB fix
- IOMMU regression fix for Picasso
- DSC display fixes
- BPC display calculation fixes
- Other misc display fixes
- Don't allow partial copy from user for DC debugfs
- SRIOV fixes
- GFX9 CSB pin count fix
- Various IP version check fixes
- DP 2.0 fixes
- Limit DCN1 MPO fix to DCN1
amdkfd:
- SVM fixes
- Fix gfx version for renoir
- Reset fixes
udl:
- timeout fix
imx:
- circular locking fix
virtio:
- NULL ptr deref fix"
* tag 'drm-next-2021-11-12' of git://anongit.freedesktop.org/drm/drm: (126 commits)
drm/ttm: Double check mem_type of BO while eviction
drm/amdgpu: add missed support for UVD IP_VERSION(3, 0, 64)
drm/amdgpu: drop jpeg IP initialization in SRIOV case
drm/amd/display: reject both non-zero src_x and src_y only for DCN1x
drm/amd/display: Add callbacks for DMUB HPD IRQ notifications
drm/amd/display: Don't lock connection_mutex for DMUB HPD
drm/amd/display: Add comment where CONFIG_DRM_AMD_DC_DCN macro ends
drm/amdkfd: Fix retry fault drain race conditions
drm/amdkfd: lower the VAs base offset to 8KB
drm/amd/display: fix exit from amdgpu_dm_atomic_check() abruptly
drm/amd/amdgpu: fix the kfd pre_reset sequence in sriov
drm/amdgpu: fix uvd crash on Polaris12 during driver unloading
drm/i915/adlp/fb: Prevent the mapping of redundant trailing padding NULL pages
drm/i915/fb: Fix rounding error in subsampled plane size calculation
drm/i915/hdmi: Turn DP++ TMDS output buffers back on in encoder->shutdown()
drm/locking: fix __stack_depot_* name conflict
drm/virtio: Fix NULL dereference error in virtio_gpu_poll
drm/amdgpu: fix SI handling in amdgpu_device_asic_has_dc_support()
drm/amdgpu: Fix dangling kfd_bo pointer for shared BOs
drm/amd/amdkfd: Don't sent command to HWS on kfd reset
...
Here is the big set of char and misc and other tiny driver subsystem
updates for 5.16-rc1.
Loads of things in here, all of which have been in linux-next for a
while with no reported problems (except for one called out below.)
Included are:
- habanana labs driver updates, including dma_buf usage,
reviewed and acked by the dma_buf maintainers
- iio driver update (going through this tree not staging as they
really do not belong going through that tree anymore)
- counter driver updates
- hwmon driver updates that the counter drivers needed, acked by
the hwmon maintainer
- xillybus driver updates
- binder driver updates
- extcon driver updates
- dma_buf module namespaces added (will cause a build error in
arm64 for allmodconfig, but that change is on its way through
the drm tree)
- lkdtm driver updates
- pvpanic driver updates
- phy driver updates
- virt acrn and nitr_enclaves driver updates
- smaller char and misc driver updates
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big set of char and misc and other tiny driver subsystem
updates for 5.16-rc1.
Loads of things in here, all of which have been in linux-next for a
while with no reported problems (except for one called out below.)
Included are:
- habanana labs driver updates, including dma_buf usage, reviewed and
acked by the dma_buf maintainers
- iio driver update (going through this tree not staging as they
really do not belong going through that tree anymore)
- counter driver updates
- hwmon driver updates that the counter drivers needed, acked by the
hwmon maintainer
- xillybus driver updates
- binder driver updates
- extcon driver updates
- dma_buf module namespaces added (will cause a build error in arm64
for allmodconfig, but that change is on its way through the drm
tree)
- lkdtm driver updates
- pvpanic driver updates
- phy driver updates
- virt acrn and nitr_enclaves driver updates
- smaller char and misc driver updates"
* tag 'char-misc-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (386 commits)
comedi: dt9812: fix DMA buffers on stack
comedi: ni_usb6501: fix NULL-deref in command paths
arm64: errata: Enable TRBE workaround for write to out-of-range address
arm64: errata: Enable workaround for TRBE overwrite in FILL mode
coresight: trbe: Work around write to out of range
coresight: trbe: Make sure we have enough space
coresight: trbe: Add a helper to determine the minimum buffer size
coresight: trbe: Workaround TRBE errata overwrite in FILL mode
coresight: trbe: Add infrastructure for Errata handling
coresight: trbe: Allow driver to choose a different alignment
coresight: trbe: Decouple buffer base from the hardware base
coresight: trbe: Add a helper to pad a given buffer area
coresight: trbe: Add a helper to calculate the trace generated
coresight: trbe: Defer the probe on offline CPUs
coresight: trbe: Fix incorrect access of the sink specific data
coresight: etm4x: Add ETM PID for Kryo-5XX
coresight: trbe: Prohibit trace before disabling TRBE
coresight: trbe: End the AUX handle on truncation
coresight: trbe: Do not truncate buffer on IRQ
coresight: trbe: Fix handling of spurious interrupts
...
This makes sure we don't hit the
BUG_ON(dmabuf->cb_in.active || dmabuf->cb_out.active);
in dma_buf_release, which could be triggered by user space closing the
dma-buf file description while there are outstanding fence callbacks
from dma_buf_poll.
Cc: stable@vger.kernel.org
Signed-off-by: Michel Dänzer <mdaenzer@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210723075857.4065-1-michel@daenzer.net
Signed-off-by: Christian König <christian.koenig@amd.com>
Because dma-buf.name can be freed in func: "dma_buf_set_name",
so, we need to acquire lock first before we read/write dma_buf.name
to prevent Use After Free(UAF) issue.
Signed-off-by: Guangming Cao <Guangming.Cao@mediatek.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211008075420.42874-1-guangming.cao@mediatek.com
In this patch(https://patchwork.freedesktop.org/patch/310349),
it add a new IOCTL to support dma-buf user to set debug name.
But it also added a limitation of this IOCTL, it needs the
attachments of dmabuf should be empty, otherwise it will fail.
For the original series, the idea was that allowing name change
mid-use could confuse the users about the dma-buf.
However, the rest of the series also makes sure each dma-buf have a unique
inode(https://patchwork.freedesktop.org/patch/310387/), and any accounting
should probably use that, without relying on the name as much.
So, removing this restriction will let dma-buf userspace users to use it
more comfortably and without any side effect.
Signed-off-by: Guangming Cao <Guangming.Cao@mediatek.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211014102551.54983-1-guangming.cao@mediatek.com
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
In order to better track where in the kernel the dma-buf code is used,
put the symbols in the namespace DMA_BUF and modify all users of the
symbols to properly import the namespace to not break the build at the
same time.
Now the output of modinfo shows the use of these symbols, making it
easier to watch for users over time:
$ modinfo drivers/misc/fastrpc.ko | grep import
import_ns: DMA_BUF
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://lore.kernel.org/r/20211010124628.17691-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A comment for the dma_buf_vmap/vunmap() is not catching up a
corresponding implementation.
Signed-off-by: Shunsuke Mie <mie@igel.co.jp>
Link: https://patchwork.freedesktop.org/patch/msgid/20211008112009.118996-1-mie@igel.co.jp
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Daniel pointed me towards this function and there are multiple obvious problems
in the implementation.
First of all the retry loop is not working as intended. In general the retry
makes only sense if you grab the reference first and then check the sequence
values.
Then we should always also wait for the exclusive fence.
It's also good practice to keep the reference around when installing callbacks
to fences you don't own.
And last the whole implementation was unnecessary complex and rather hard to
understand which could lead to probably unexpected behavior of the IOCTL.
Fix all this by reworking the implementation from scratch. Dropping the
whole RCU approach and taking the lock instead.
Only mildly tested and needs a thoughtful review of the code.
Pushing through drm-misc-next to avoid merge conflicts and give the code
another round of testing.
v2: fix the reference counting as well
v3: keep the excl fence handling as is for stable
v4: back to testing all fences, drop RCU
v5: handle in and out separately
v6: add missing clear of events
v7: change coding style as suggested by Michel, drop unused variables
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Michel Dänzer <mdaenzer@redhat.com>
CC: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210720131110.88512-1-christian.koenig@amd.com
It is expected from the clients to follow the below steps on an imported
dmabuf fd:
a) dmabuf = dma_buf_get(fd) // Get the dmabuf from fd
b) dma_buf_attach(dmabuf); // Clients attach to the dmabuf
o Here the kernel does some slab allocations, say for
dma_buf_attachment and may be some other slab allocation in the
dmabuf->ops->attach().
c) Client may need to do dma_buf_map_attachment().
d) Accordingly dma_buf_unmap_attachment() should be called.
e) dma_buf_detach () // Clients detach to the dmabuf.
o Here the slab allocations made in b) are freed.
f) dma_buf_put(dmabuf) // Can free the dmabuf if it is the last
reference.
Now say an erroneous client failed at step c) above thus it directly
called dma_buf_put(), step f) above. Considering that it may be the last
reference to the dmabuf, buffer will be freed with pending attachments
left to the dmabuf which can show up as the 'memory leak'. This should
at least be reported as the WARN().
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1627043468-16381-1-git-send-email-charante@codeaurora.org
Signed-off-by: Christian König <christian.koenig@amd.com>
Dmabuf sysfs stat is used for dmabuf info track.
But these file maybe still in use after buffer released,
should clear it before buffer release.
Signed-off-by: Guangming Cao <Guangming.Cao@mediatek.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210720103158.83439-1-guangming.cao@mediatek.com
Signed-off-by: Christian König <christian.koenig@amd.com>
The DMA-BUF attachment statistics form a subset of the DMA-BUF
sysfs statistics that recently merged to the drm-misc tree. They are not
UABI yet since they have not merged to the upstream Linux kernel.
Since there has been a reported a performance regression due to the
overhead of sysfs directory creation/teardown during
dma_buf_attach()/dma_buf_detach(), this patch deletes the DMA-BUF
attachment statistics from sysfs.
Fixes: bdb8d06dfe ("dmabuf: Add the capability to expose DMA-BUF stats in sysfs")
Signed-off-by: Hridya Valsaraju <hridya@google.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210713040742.2680135-1-hridya@google.com
Signed-off-by: Christian König <christian.koenig@amd.com>
Christian and me realized we have a pretty massive disconnect about
different interpretations of what dma_resv is used for by different
drivers. The discussion is much, much bigger than this change here,
but this is an important one:
Non-dynamic exporters must guarantee that the memory they return is
ready for use. They cannot expect importers to wait for the exclusive
fence. Only dynamic importers are required to obey the dma_resv fences
strictly (and more patches are needed to define exactly what this
means).
Christian has patches to update nouvea, radeon and amdgpu. The only
other driver using both ttm and supporting dma-buf export is qxl,
which only uses synchronous ttm_bo_move.
v2: To hammer this in document that dynamic importers _must_ wait for
the exclusive fence after having called dma_buf_map_attachment.
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: Christian König <ckoenig.leichtzumerken@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210621151758.2347474-1-daniel.vetter@ffwll.ch
Overview
========
The patch adds DMA-BUF statistics to /sys/kernel/dmabuf/buffers. It
allows statistics to be enabled for each DMA-BUF in sysfs by enabling
the config CONFIG_DMABUF_SYSFS_STATS.
The following stats will be exposed by the interface:
/sys/kernel/dmabuf/buffers/<inode_number>/exporter_name
/sys/kernel/dmabuf/buffers/<inode_number>/size
/sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attach_uid>/device
/sys/kernel/dmabuf/buffers/<inode_number>/attachments/<attach_uid>/map_counter
The inode_number is unique for each DMA-BUF and was added earlier [1]
in order to allow userspace to track DMA-BUF usage across different
processes.
Use Cases
=========
The interface provides a way to gather DMA-BUF per-buffer statistics
from production devices. These statistics will be used to derive DMA-BUF
per-exporter stats and per-device usage stats for Android Bug reports.
The corresponding userspace changes can be found at [2].
Telemetry tools will also capture this information(along with other
memory metrics) periodically as well as on important events like a
foreground app kill (which might have been triggered by Low Memory
Killer). It will also contribute to provide a snapshot of the system
memory usage on other events such as OOM kills and Application Not
Responding events.
Background
==========
Currently, there are two existing interfaces that provide information
about DMA-BUFs.
1) /sys/kernel/debug/dma_buf/bufinfo
debugfs is however unsuitable to be mounted in production systems and
cannot be considered as an alternative to the sysfs interface being
proposed.
2) proc/<pid>/fdinfo/<fd>
The proc/<pid>/fdinfo/<fd> files expose information about DMA-BUF fds.
However, the existing procfs interfaces can only provide information
about the buffers for which processes hold fds or have the buffers
mmapped into their address space. Since the procfs interfaces alone
cannot provide a full picture of all DMA-BUFs in the system, there is
the need for an alternate interface to provide this information on
production systems.
The patch contains the following major improvements over v1:
1) Each attachment is represented by its own directory to allow creating
a symlink to the importing device and to also provide room for future
expansion.
2) The number of distinct mappings of each attachment is exposed in a
separate file.
3) The per-buffer statistics are now in /sys/kernel/dmabuf/buffers
inorder to make the interface expandable in future.
All of the improvements above are based on suggestions/feedback from
Daniel Vetter and Christian König.
A shell script that can be run on a classic Linux environment to read
out the DMA-BUF statistics can be found at [3](suggested by John
Stultz).
[1]: https://lore.kernel.org/patchwork/patch/1088791/
[2]: https://android-review.googlesource.com/q/topic:%22dmabuf-sysfs%22+(status:open%20OR%20status:merged)
[3]: https://android-review.googlesource.com/c/platform/system/memory/libmeminfo/+/1549734
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Hridya Valsaraju <hridya@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210603214758.2955251-1-hridya@google.com
The functions can be called both in _rcu context as well
as while holding the lock.
v2: add some kerneldoc as suggested by Daniel
v3: fix indentation
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-7-christian.koenig@amd.com
When the comment needs to state explicitly that this
doesn't get a reference to the object then the function
is named rather badly.
Rename the function and use rcu_dereference_check(), this
way it can be used from both rcu as well as lock protected
critical sections.
v2: improve kerneldoc as suggested by Daniel
v3: use dma_resv_excl_fence as function name
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-4-christian.koenig@amd.com
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Merge tag 'v5.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next
Backmerge v5.11-rc5 into drm-next to clean up a bunch of conflicts we are dragging around.
Signed-off-by: Dave Airlie <airlied@redhat.com>
We have too many people abusing the struct page they can get at but
really shouldn't in importers. Aside from that the backing page might
simply not exist (for dynamic p2p mappings) looking at it and using it
e.g. for mmap can also wreak the page handling of the exporter
completely. Importers really must go through the proper interface like
dma_buf_mmap for everything.
I'm semi-tempted to enforce this for dynamic importers since those
really have no excuse at all to break the rules.
Unfortuantely we can't store the right pointers somewhere safe to make
sure we oops on something recognizable, so best is to just wrangle
them a bit by flipping all the bits. At least on x86 kernel addresses
have all their high bits sets and the struct page array is fairly low
in the kernel mapping, so flipping all the bits gives us a very high
pointer in userspace and hence excellent chances for an invalid
dereference.
v2: Add a note to the @map_dma_buf hook that exporters shouldn't do
fancy caching tricks, which would blow up with this address scrambling
trick here (Chris)
Enable by default when CONFIG_DMA_API_DEBUG is enabled.
v3: Only one copy of the mangle/unmangle code (Christian)
v4: #ifdef, not #if (0day)
v5: sg_table can also be an ERR_PTR (Chris, Christian)
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Stevens <stevensd@chromium.org>
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210115164739.3958206-1-daniel.vetter@ffwll.ch
It is observed 'use-after-free' on the dmabuf's file->f_inode with the
race between closing the dmabuf file and reading the dmabuf's debug
info.
Consider the below scenario where P1 is closing the dma_buf file
and P2 is reading the dma_buf's debug info in the system:
P1 P2
dma_buf_debug_show()
dma_buf_put()
__fput()
file->f_op->release()
dput()
....
dentry_unlink_inode()
iput(dentry->d_inode)
(where the inode is freed)
mutex_lock(&db_list.lock)
read 'dma_buf->file->f_inode'
(the same inode is freed by P1)
mutex_unlock(&db_list.lock)
dentry->d_op->d_release()-->
dma_buf_release()
.....
mutex_lock(&db_list.lock)
removes the dmabuf from the list
mutex_unlock(&db_list.lock)
In the above scenario, when dma_buf_put() is called on a dma_buf, it
first frees the dma_buf's file->f_inode(=dentry->d_inode) and then
removes this dma_buf from the system db_list. In between P2 traversing
the db_list tries to access this dma_buf's file->f_inode that was freed
by P1 which is a use-after-free case.
Since, __fput() calls f_op->release first and then later calls the
d_op->d_release, move the dma_buf's db_list removal from d_release() to
f_op->release(). This ensures that dma_buf's file->f_inode is not
accessed after it is released.
Cc: <stable@vger.kernel.org> # 5.4.x-
Fixes: 4ab59c3c63 ("dma-buf: Move dma_buf_release() from fops to dentry_ops")
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/1609857399-31549-1-git-send-email-charante@codeaurora.org
Motivated by a discussion with Christian and Thomas: Try to untangle a
bit what's relevant for importers and what's relevant for exporters.
Also add an assert that really only dynamic importers use the api
function, anything else doesn't make sense.
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20201211155843.3348718-4-daniel.vetter@ffwll.ch
Add the new vma_set_file() function to allow changing
vma->vm_file with the necessary refcount dance.
v2: add more users of this.
v3: add missing EXPORT_SYMBOL, rebase on mmap cleanup,
add comments why we drop the reference on two occasions.
v4: make it clear that changing an anonymous vma is illegal.
v5: move vma_set_file to mm/util.c
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v2)
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://patchwork.freedesktop.org/patch/399360/
Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..."
adds a workaround for a bug in mmap_region.
As the comment states ->mmap() callback can change
vma->vm_file and so we might call fput() on the wrong file.
Revert the workaround and proper fix this in mmap_region.
v2: drop the extra if in dma_buf_mmap as well
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://patchwork.freedesktop.org/patch/399359/
The kernel test robot is not happy with that.
This reverts commit 0227da01f2.
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/394772/
The kernel test robot is not happy with that.
This reverts commit 2b5b95b1ff.
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/394773/
Here is the warning message:
drivers/dma-buf/dma-buf.c:917 dma_buf_map_attachment()
error: 'sg_table' dereferencing possible ERR_PTR()
Fix by adding error checking before dereferencing the pointer.
Fixes: ac80cd17a6 ("dma-buf: Clarify that dma-buf sg lists are page aligned")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jianxin Xiong <jianxin.xiong@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/398485/
Add the new vma_set_file() function to allow changing
vma->vm_file with the necessary refcount dance.
v2: add more users of this.
v3: add missing EXPORT_SYMBOL, rebase on mmap cleanup,
add comments why we drop the reference on two occasions.
v4: make it clear that changing an anonymous vma is illegal.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v2)
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/394773/
Patch "495c10cc1c0c CHROMIUM: dma-buf: restore args..."
adds a workaround for a bug in mmap_region.
As the comment states ->mmap() callback can change
vma->vm_file and so we might call fput() on the wrong file.
Revert the workaround and proper fix this in mmap_region.
v2: drop the extra if in dma_buf_mmap as well
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/394772/
The dma-buf API have been used under the assumption that the sg lists
returned from dma_buf_map_attachment() are fully page aligned. Lots of
stuff can break otherwise all over the place. Clarify this in the
documentation and add a check when DMA API debug is enabled.
Signed-off-by: Jianxin Xiong <jianxin.xiong@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1602692161-107096-1-git-send-email-jianxin.xiong@intel.com
This patch updates dma_buf_vunmap() and dma-buf's vunmap callback to
use struct dma_buf_map. The interfaces used to receive a buffer address.
This address is now given in an instance of the structure.
Users of the functions are updated accordingly. This is only an interface
change. It is currently expected that dma-buf memory can be accessed with
system memory load/store operations.
v2:
* include dma-buf-heaps and i915 selftests (kernel test robot)
* initialize cma_obj before using it in drm_gem_cma_free_object()
(kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Tomasz Figa <tfiga@chromium.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200925115601.23955-4-tzimmermann@suse.de
This patch updates dma_buf_vmap() and dma-buf's vmap callback to use
struct dma_buf_map.
The interfaces used to return a buffer address. This address now gets
stored in an instance of the structure that is given as an additional
argument. The functions return an errno code on errors.
Users of the functions are updated accordingly. This is only an interface
change. It is currently expected that dma-buf memory can be accessed with
system memory load/store operations.
v3:
* update fastrpc driver (kernel test robot)
v2:
* always clear map parameter in dma_buf_vmap() (Daniel)
* include dma-buf-heaps and i915 selftests (kernel test robot)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Tomasz Figa <tfiga@chromium.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200925115601.23955-3-tzimmermann@suse.de
The new type struct dma_buf_map represents a mapping of dma-buf memory
into kernel space. It contains a flag, is_iomem, that signals users to
access the mapped memory with I/O operations instead of regular loads
and stores.
It was assumed that DMA buffer memory can be accessed with regular load
and store operations. Some architectures, such as sparc64, require the
use of I/O operations to access dma-map buffers that are located in I/O
memory. Providing struct dma_buf_map allows drivers to implement this.
This was specifically a problem when refreshing the graphics framebuffer
on such systems. [1]
As the first step, struct dma_buf stores an instance of struct dma_buf_map
internally. Afterwards, dma-buf's vmap and vunmap interfaces are be
converted. Finally, affected drivers can be fixed.
v3:
* moved documentation into separate patch
* test for NULL pointers with !<ptr>
[1] https://lore.kernel.org/dri-devel/20200725191012.GA434957@ravnborg.org/
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200925115601.23955-2-tzimmermann@suse.de
NULL pointer dereference is observed while exporting the dmabuf but
failed to allocate the 'struct file' which results into the dropping of
the allocated dentry corresponding to this file in the dmabuf fs, which
is ending up in dma_buf_release() and accessing the uninitialzed
dentry->d_fsdata.
Call stack on 5.4 is below:
dma_buf_release+0x2c/0x254 drivers/dma-buf/dma-buf.c:88
__dentry_kill+0x294/0x31c fs/dcache.c:584
dentry_kill fs/dcache.c:673 [inline]
dput+0x250/0x380 fs/dcache.c:859
path_put+0x24/0x40 fs/namei.c:485
alloc_file_pseudo+0x1a4/0x200 fs/file_table.c:235
dma_buf_getfile drivers/dma-buf/dma-buf.c:473 [inline]
dma_buf_export+0x25c/0x3ec drivers/dma-buf/dma-buf.c:585
Fix this by checking for the valid pointer in the dentry->d_fsdata.
Fixes: 4ab59c3c63 ("dma-buf: Move dma_buf_release() from fops to dentry_ops")
Cc: <stable@vger.kernel.org> [5.7+]
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/391319/
Signed-off-by: Christian König <christian.koenig@amd.com>
Fix W=1 compile warnings (invalid kerneldoc):
drivers/dma-buf/dma-buf.c:328: warning: Function parameter or member 'dmabuf' not described in 'dma_buf_set_name'
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200819175134.19261-1-krzk@kernel.org
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Merge v5.8-rc6 into drm-next
I've got a silent conflict + two trees based on fixes to merge.
Fixes a silent merge with amdgpu
Signed-off-by: Dave Airlie <airlied@redhat.com>
There exists a sleep-while-atomic bug while accessing the dmabuf->name
under mutex in the dmabuffs_dname(). This is caused from the SELinux
permissions checks on a process where it tries to validate the inherited
files from fork() by traversing them through iterate_fd() (which
traverse files under spin_lock) and call
match_file(security/selinux/hooks.c) where the permission checks happen.
This audit information is logged using dump_common_audit_data() where it
calls d_path() to get the file path name. If the file check happen on
the dmabuf's fd, then it ends up in ->dmabuffs_dname() and use mutex to
access dmabuf->name. The flow will be like below:
flush_unauthorized_files()
iterate_fd()
spin_lock() --> Start of the atomic section.
match_file()
file_has_perm()
avc_has_perm()
avc_audit()
slow_avc_audit()
common_lsm_audit()
dump_common_audit_data()
audit_log_d_path()
d_path()
dmabuffs_dname()
mutex_lock()--> Sleep while atomic.
Call trace captured (on 4.19 kernels) is below:
___might_sleep+0x204/0x208
__might_sleep+0x50/0x88
__mutex_lock_common+0x5c/0x1068
__mutex_lock_common+0x5c/0x1068
mutex_lock_nested+0x40/0x50
dmabuffs_dname+0xa0/0x170
d_path+0x84/0x290
audit_log_d_path+0x74/0x130
common_lsm_audit+0x334/0x6e8
slow_avc_audit+0xb8/0xf8
avc_has_perm+0x154/0x218
file_has_perm+0x70/0x180
match_file+0x60/0x78
iterate_fd+0x128/0x168
selinux_bprm_committing_creds+0x178/0x248
security_bprm_committing_creds+0x30/0x48
install_exec_creds+0x1c/0x68
load_elf_binary+0x3a4/0x14e0
search_binary_handler+0xb0/0x1e0
So, use spinlock to access dmabuf->name to avoid sleep-while-atomic.
Cc: <stable@vger.kernel.org> [5.3+]
Signed-off-by: Charan Teja Kalla <charante@codeaurora.org>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Acked-by: Christian König <christian.koenig@amd.com>
[sumits: added comment to spinlock_t definition to avoid warning]
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/a83e7f0d-4e54-9848-4b58-e1acdbe06735@codeaurora.org
Cross-subsystem Changes:
- Improve dma-buf docs.
Core Changes:
- Add NV15, Q410, Q401 yuv formats.
- Add uncompressed AFBC modifier.
- Add DP helepr for reading Ignore MSA from DPCD.
- Add missing panel type for some panels
- Optimize drm/mm hole handling.
- Constify connector to infoframe functions.
- Add debugfs for VRR monitor range.
Driver Changes:
- Assorted small bugfixes in panfrost, malidp, panel/otm8009a.
- Convert tfp410 dt bindings to yaml, and rework time calculations.
- Add support for a few more simple panels.
- Cleanups and optimizations for ast.
- Allow adv7511 and simple-bridge to be used without connector creation.
- Cleanups to dw-hdmi function prototypes.
- Remove enabled bool from tiny/repaper and mipi-dbi, atomic handles it.
- Remove unused header file from dw-mipi-dsi
- Begin removing ttm_bo->offset.
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Merge tag 'drm-misc-next-2020-06-26' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for v5.9:
Cross-subsystem Changes:
- Improve dma-buf docs.
Core Changes:
- Add NV15, Q410, Q401 yuv formats.
- Add uncompressed AFBC modifier.
- Add DP helepr for reading Ignore MSA from DPCD.
- Add missing panel type for some panels
- Optimize drm/mm hole handling.
- Constify connector to infoframe functions.
- Add debugfs for VRR monitor range.
Driver Changes:
- Assorted small bugfixes in panfrost, malidp, panel/otm8009a.
- Convert tfp410 dt bindings to yaml, and rework time calculations.
- Add support for a few more simple panels.
- Cleanups and optimizations for ast.
- Allow adv7511 and simple-bridge to be used without connector creation.
- Cleanups to dw-hdmi function prototypes.
- Remove enabled bool from tiny/repaper and mipi-dbi, atomic handles it.
- Remove unused header file from dw-mipi-dsi
- Begin removing ttm_bo->offset.
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b1e53620-7937-895c-bfcf-ed208be59c7c@linux.intel.com
