Commit Graph

23 Commits

Author SHA1 Message Date
Thomas Zimmermann e0106ac978 Revert "drm/shmem-helper: Switch to reservation lock"
This reverts commit 67b7836d44.

The locking appears incomplete. A caller of SHMEM helper's pin
function never acquires the dma-buf reservation lock. So we get

  WARNING: CPU: 3 PID: 967 at drivers/gpu/drm/drm_gem_shmem_helper.c:243 drm_gem_shmem_pin+0x42/0x90 [drm_shmem_helper]

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230228152612.19971-1-tzimmermann@suse.de
2023-02-28 16:41:32 +01:00
Dmitry Osipenko 67b7836d44 drm/shmem-helper: Switch to reservation lock
Replace all drm-shmem locks with a GEM reservation lock. This makes locks
consistent with dma-buf locking convention where importers are responsible
for holding reservation lock for all operations performed over dma-bufs,
preventing deadlock between dma-buf importers and exporters.

Suggested-by: Daniel Vetter <daniel@ffwll.ch>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://lore.kernel.org/all/20230108210445.3948344-8-dmitry.osipenko@collabora.com/
2023-02-27 07:10:56 +03:00
Dmitry Osipenko 3842d671d7 drm/shmem-helper: Put booleans in the end of struct drm_gem_shmem_object
Group all 1-bit boolean members of struct drm_gem_shmem_object in the end
of the structure, allowing compiler to pack data better and making code to
look more consistent.

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://lore.kernel.org/all/20230108210445.3948344-5-dmitry.osipenko@collabora.com/
2023-02-27 07:10:03 +03:00
Liu Zixian 2b8428a10f
drm: correct comments
On failure, these functions return error pointer, not NULL.

Signed-off-by: Liu Zixian <liuzixian4@huawei.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220718015357.1722-1-liuzixian4@huawei.com
2022-07-21 12:16:10 +02:00
Dave Airlie 54f43c17d6 drm-misc-next for v5.18:
UAPI Changes:
 
 Cross-subsystem Changes:
 - Split out panel-lvds and lvds dt bindings .
 - Put yes/no on/off disabled/enabled strings in linux/string_helpers.h
   and use it in drivers and tomoyo.
 - Clarify dma_fence_chain and dma_fence_array should never include eachother.
 - Flatten chains in syncobj's.
 - Don't double add in fbdev/defio when page is already enlisted.
 - Don't sort deferred-I/O pages by default in fbdev.
 
 Core Changes:
 - Fix missing pm_runtime_put_sync in bridge.
 - Set modifier support to only linear fb modifier if drivers don't
   advertise support.
 - As a result, we remove allow_fb_modifiers.
 - Add missing clear for EDID Deep Color Modes in drm_reset_display_info.
 - Assorted documentation updates.
 - Warn once in drm_clflush if there is no arch support.
 - Add missing select for dp helper in drm_panel_edp.
 - Assorted small fixes.
 - Improve fb-helper's clipping handling.
 - Don't dump shmem mmaps in a core dump.
 - Add accounting to ttm resource manager, and use it in amdgpu.
 - Allow querying the detected eDP panel through debugfs.
 - Add helpers for xrgb8888 to 8 and 1 bits gray.
 - Improve drm's buddy allocator.
 - Add selftests for the buddy allocator.
 
 Driver Changes:
 - Add support for nomodeset to a lot of drm drivers.
 - Use drm_module_*_driver in a lot of drm drivers.
 - Assorted small fixes to bridge/lt9611, v3d, vc4, vmwgfx, mxsfb, nouveau,
   bridge/dw-hdmi, panfrost, lima, ingenic, sprd, bridge/anx7625, ti-sn65dsi86.
 - Add bridge/it6505.
 - Create DP and DVI-I connectors in ast.
 - Assorted nouveau backlight fixes.
 - Rework amdgpu reset handling.
 - Add dt bindings for ingenic,jz4780-dw-hdmi.
 - Support reading edid through aux channel in ingenic.
 - Add a drm driver for Solomon SSD130x OLED displays.
 - Add simple support for sharp LQ140M1JW46.
 - Add more panels to nt35560.
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Merge tag 'drm-misc-next-2022-02-23' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

drm-misc-next for v5.18:

UAPI Changes:

Cross-subsystem Changes:
- Split out panel-lvds and lvds dt bindings .
- Put yes/no on/off disabled/enabled strings in linux/string_helpers.h
  and use it in drivers and tomoyo.
- Clarify dma_fence_chain and dma_fence_array should never include eachother.
- Flatten chains in syncobj's.
- Don't double add in fbdev/defio when page is already enlisted.
- Don't sort deferred-I/O pages by default in fbdev.

Core Changes:
- Fix missing pm_runtime_put_sync in bridge.
- Set modifier support to only linear fb modifier if drivers don't
  advertise support.
- As a result, we remove allow_fb_modifiers.
- Add missing clear for EDID Deep Color Modes in drm_reset_display_info.
- Assorted documentation updates.
- Warn once in drm_clflush if there is no arch support.
- Add missing select for dp helper in drm_panel_edp.
- Assorted small fixes.
- Improve fb-helper's clipping handling.
- Don't dump shmem mmaps in a core dump.
- Add accounting to ttm resource manager, and use it in amdgpu.
- Allow querying the detected eDP panel through debugfs.
- Add helpers for xrgb8888 to 8 and 1 bits gray.
- Improve drm's buddy allocator.
- Add selftests for the buddy allocator.

Driver Changes:
- Add support for nomodeset to a lot of drm drivers.
- Use drm_module_*_driver in a lot of drm drivers.
- Assorted small fixes to bridge/lt9611, v3d, vc4, vmwgfx, mxsfb, nouveau,
  bridge/dw-hdmi, panfrost, lima, ingenic, sprd, bridge/anx7625, ti-sn65dsi86.
- Add bridge/it6505.
- Create DP and DVI-I connectors in ast.
- Assorted nouveau backlight fixes.
- Rework amdgpu reset handling.
- Add dt bindings for ingenic,jz4780-dw-hdmi.
- Support reading edid through aux channel in ingenic.
- Add a drm driver for Solomon SSD130x OLED displays.
- Add simple support for sharp LQ140M1JW46.
- Add more panels to nt35560.

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/686ec871-e77f-c230-22e5-9e3bb80f064a@linux.intel.com
2022-02-25 05:50:18 +10:00
Thomas Zimmermann d315bdbfeb drm/gem-shmem: Set vm_ops in static initializer
Initialize default vm_ops in static initialization of the GEM SHMEM funcs,
instead of the mmap code. It's simply better style. GEM helpers will later
set a VMA's vm_ops from the default automatically.

v2:
	* also update the drivers that build upon GEM SHMEM

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220209155634.3994-2-tzimmermann@suse.de
2022-02-14 09:42:01 +01:00
Lucas De Marchi 7938f42181 dma-buf-map: Rename to iosys-map
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
2022-02-07 16:35:35 -08:00
Thomas Zimmermann a193f3b4e0 drm/shmem-helper: Pass GEM shmem object in public interfaces
Change all GEM SHMEM object functions that receive a GEM object
of type struct drm_gem_object to expect an object of type
struct drm_gem_shmem_object instead.

This change reduces the number of upcasts from struct drm_gem_object
by moving them into callers. The C compiler can now verify that the
GEM SHMEM functions are called with the correct type.

For consistency, the patch also renames drm_gem_shmem_free_object to
drm_gem_shmem_free. It further updates documentation for a number of
functions.

v3:
	* fix docs for drm_gem_shmem_object_free()
v2:
	* mention _object_ callbacks in docs (Daniel)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211108093149.7226-4-tzimmermann@suse.de
2021-11-15 11:46:13 +01:00
Thomas Zimmermann c7fbcb7149 drm/shmem-helper: Export dedicated wrappers for GEM object functions
Wrap GEM SHMEM functions for struct drm_gem_object_funcs and update
all callers. This will allow for an update of the public interfaces
of the GEM SHMEM helper library.

v2:
	* fix docs for drm_gem_shmem_object_print_info()

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211108093149.7226-3-tzimmermann@suse.de
2021-11-15 11:45:01 +01:00
Thomas Zimmermann 5a363c2067 drm/shmem-helper: Unexport drm_gem_shmem_create_with_handle()
Turn drm_gem_shmem_create_with_handle() into an internal helper
function. It's not used outside of the compilation unit.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211108093149.7226-2-tzimmermann@suse.de
2021-11-15 11:03:57 +01:00
Thomas Zimmermann 2f04636f49 drm/shmem-helper: Removed drm_gem_shmem_create_object_cached()
Cached page mappings are now the default for SHMEM GEM objects. Remove
the obsolete create function for cached mappings.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201117133156.26822-3-tzimmermann@suse.de
2020-11-24 09:10:33 +01:00
Thomas Zimmermann 0cf2ef46c6 drm/shmem-helper: Use cached mappings by default
SHMEM-buffer backing storage is allocated from system memory; which is
typically cachable. The default mode for SHMEM objects is writecombine
though.

Unify SHMEM semantics by defaulting to cached mappings. The exception
is pages imported via dma-buf. DMA memory is usually not cached.

DRM drivers that require write-combined mappings set the map_wc flag
in struct drm_gem_shmem_object to true. This currently affects lima,
panfrost and v3d.

The drivers mgag200, udl, virtio and vkms continue to use default
shmem mappings.

The drivers cirrus and gm12u320 change caching flags. Both used
writecombine and now switch over to shmem defaults. Both drivers use
SHMEM objects as shadow buffers for internal video memory, so cached
mappings will not affect them negatively.

v3:
	* set value of shmem pointer before dereferencing it in
	  __drm_gem_shmem_create() (Dan, kernel test robot)
v2:
	* recreate patch on top of latest SHMEM helpers
	* update lima, panfrost, v3d to select writecombine (Daniel, Rob)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201117133156.26822-2-tzimmermann@suse.de
2020-11-24 09:10:21 +01:00
Thomas Zimmermann 49a3f51dfe drm/gem: Use struct dma_buf_map in GEM vmap ops and convert GEM backends
This patch replaces the vmap/vunmap's use of raw pointers in GEM object
functions with instances of struct dma_buf_map. GEM backends are
converted as well. For most of them, this simply changes the returned type.

TTM-based drivers now return information about the location of the memory,
either system or I/O memory. GEM VRAM helpers and qxl now use ttm_bo_vmap()
et al. Amdgpu, nouveau and radeon use drm_gem_ttm_vmap() et al instead of
implementing their own vmap callbacks.

v7:
	* init QXL cursor to mapped BO buffer (kernel test robot)
v5:
	* update vkms after switch to shmem
v4:
	* use ttm_bo_vmap(), drm_gem_ttm_vmap(), et al. (Daniel, Christian)
	* fix a trailing { in drm_gem_vmap()
	* remove several empty functions instead of converting them (Daniel)
	* comment uses of raw pointers with a TODO (Daniel)
	* TODO list: convert more helpers to use struct dma_buf_map

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Christian König <christian.koenig@amd.com>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103093015.1063-7-tzimmermann@suse.de
2020-11-09 09:19:24 +01:00
Thomas Zimmermann d18ee06b48 drm/shmem-helper: Add .gem_create_object helper that sets map_cached flag
The helper drm_gem_shmem_create_object_cached() allocates an GEM SHMEM
object and sets the map_cached flag. Useful for drivers that want cached
mappings.

v3:
	* style fixes

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200609090820.20256-2-tzimmermann@suse.de
2020-06-10 10:16:43 +02:00
Gerd Hoffmann 1cad629257 drm/shmem: add support for per object caching flags.
Add map_cached bool to drm_gem_shmem_object, to request cached mappings
on a per-object base.  Check the flag before adding writecombine to
pgprot bits.

Cc: stable@vger.kernel.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Tested-by: Guillaume Gardet <Guillaume.Gardet@arm.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200226154752.24328-2-kraxel@redhat.com
2020-02-27 13:54:38 +01:00
Dave Airlie 77e0723bd2 Linux 5.4-rc7
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Merge v5.4-rc7 into drm-next

We have the i915 security fixes to backmerge, but first
let's clear the decks for other drivers to avoid a bigger
mess.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2019-11-14 05:53:10 +10:00
Rob Herring 105401b659 drm/shmem: Add docbook comments for drm_gem_shmem_object madvise fields
Add missing docbook comments to madvise fields in struct
drm_gem_shmem_object which fixes these warnings:

include/drm/drm_gem_shmem_helper.h:87: warning: Function parameter or member 'madv' not described in 'drm_gem_shmem_object'
include/drm/drm_gem_shmem_helper.h:87: warning: Function parameter or member 'madv_list' not described in 'drm_gem_shmem_object'

Fixes: 17acb9f35e ("drm/shmem: Add madvise state and purge helpers")
Reported-by: Sean Paul <sean@poorly.run>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20191101153754.22803-1-robh@kernel.org
2019-11-06 17:57:42 -06:00
Gerd Hoffmann eee9a2e0ad drm/shmem: drop DEFINE_DRM_GEM_SHMEM_FOPS
DEFINE_DRM_GEM_SHMEM_FOPS is identical
to DEFINE_DRM_GEM_FOPS now, drop it.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20191016115203.20095-6-kraxel@redhat.com
2019-10-17 13:59:16 +02:00
Gerd Hoffmann 0be8958936 drm/shmem: switch shmem helper to &drm_gem_object_funcs.mmap
Switch gem shmem helper to the new mmap() workflow,
from &gem_driver.fops.mmap to &drm_gem_object_funcs.mmap.

v2: Fix vm_flags and vm_page_prot handling.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20191016115203.20095-3-kraxel@redhat.com
2019-10-17 13:59:16 +02:00
Rob Herring edbd7f318c drm/shmem: Use mutex_trylock in drm_gem_shmem_purge
Lockdep reports a circular locking dependency with pages_lock taken in
the shrinker callback. The deadlock can't actually happen with current
users at least as a BO will never be purgeable when pages_lock is held.
To be safe, let's use mutex_trylock() instead and bail if a BO is locked
already.

WARNING: possible circular locking dependency detected
5.3.0-rc1+ #100 Tainted: G             L
------------------------------------------------------
kswapd0/171 is trying to acquire lock:
000000009b9823fd (&shmem->pages_lock){+.+.}, at: drm_gem_shmem_purge+0x20/0x40

but task is already holding lock:
00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (fs_reclaim){+.+.}:
       fs_reclaim_acquire.part.18+0x34/0x40
       fs_reclaim_acquire+0x20/0x28
       __kmalloc_node+0x6c/0x4c0
       kvmalloc_node+0x38/0xa8
       drm_gem_get_pages+0x80/0x1d0
       drm_gem_shmem_get_pages+0x58/0xa0
       drm_gem_shmem_get_pages_sgt+0x48/0xd0
       panfrost_mmu_map+0x38/0xf8 [panfrost]
       panfrost_gem_open+0xc0/0xe8 [panfrost]
       drm_gem_handle_create_tail+0xe8/0x198
       drm_gem_handle_create+0x3c/0x50
       panfrost_gem_create_with_handle+0x70/0xa0 [panfrost]
       panfrost_ioctl_create_bo+0x48/0x80 [panfrost]
       drm_ioctl_kernel+0xb8/0x110
       drm_ioctl+0x244/0x3f0
       do_vfs_ioctl+0xbc/0x910
       ksys_ioctl+0x78/0xa8
       __arm64_sys_ioctl+0x1c/0x28
       el0_svc_common.constprop.0+0x90/0x168
       el0_svc_handler+0x28/0x78
       el0_svc+0x8/0xc

-> #0 (&shmem->pages_lock){+.+.}:
       __lock_acquire+0xa2c/0x1d70
       lock_acquire+0xdc/0x228
       __mutex_lock+0x8c/0x800
       mutex_lock_nested+0x1c/0x28
       drm_gem_shmem_purge+0x20/0x40
       panfrost_gem_shrinker_scan+0xc0/0x180 [panfrost]
       do_shrink_slab+0x208/0x500
       shrink_slab+0x10c/0x2c0
       shrink_node+0x28c/0x4d8
       balance_pgdat+0x2c8/0x570
       kswapd+0x22c/0x638
       kthread+0x128/0x130
       ret_from_fork+0x10/0x18

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
                               lock(&shmem->pages_lock);
                               lock(fs_reclaim);
  lock(&shmem->pages_lock);

 *** DEADLOCK ***

3 locks held by kswapd0/171:
 #0: 00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40
 #1: 00000000ceb37808 (shrinker_rwsem){++++}, at: shrink_slab+0xbc/0x2c0
 #2: 00000000f31efa81 (&pfdev->shrinker_lock){+.+.}, at: panfrost_gem_shrinker_scan+0x34/0x180 [panfrost]

Fixes: 17acb9f35e ("drm/shmem: Add madvise state and purge helpers")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-6-robh@kernel.org
2019-08-28 10:02:39 -05:00
Rob Herring dfbc7a46b9 drm/shmem: Use mutex_trylock in drm_gem_shmem_purge
Lockdep reports a circular locking dependency with pages_lock taken in
the shrinker callback. The deadlock can't actually happen with current
users at least as a BO will never be purgeable when pages_lock is held.
To be safe, let's use mutex_trylock() instead and bail if a BO is locked
already.

WARNING: possible circular locking dependency detected
5.3.0-rc1+ #100 Tainted: G             L
------------------------------------------------------
kswapd0/171 is trying to acquire lock:
000000009b9823fd (&shmem->pages_lock){+.+.}, at: drm_gem_shmem_purge+0x20/0x40

but task is already holding lock:
00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (fs_reclaim){+.+.}:
       fs_reclaim_acquire.part.18+0x34/0x40
       fs_reclaim_acquire+0x20/0x28
       __kmalloc_node+0x6c/0x4c0
       kvmalloc_node+0x38/0xa8
       drm_gem_get_pages+0x80/0x1d0
       drm_gem_shmem_get_pages+0x58/0xa0
       drm_gem_shmem_get_pages_sgt+0x48/0xd0
       panfrost_mmu_map+0x38/0xf8 [panfrost]
       panfrost_gem_open+0xc0/0xe8 [panfrost]
       drm_gem_handle_create_tail+0xe8/0x198
       drm_gem_handle_create+0x3c/0x50
       panfrost_gem_create_with_handle+0x70/0xa0 [panfrost]
       panfrost_ioctl_create_bo+0x48/0x80 [panfrost]
       drm_ioctl_kernel+0xb8/0x110
       drm_ioctl+0x244/0x3f0
       do_vfs_ioctl+0xbc/0x910
       ksys_ioctl+0x78/0xa8
       __arm64_sys_ioctl+0x1c/0x28
       el0_svc_common.constprop.0+0x90/0x168
       el0_svc_handler+0x28/0x78
       el0_svc+0x8/0xc

-> #0 (&shmem->pages_lock){+.+.}:
       __lock_acquire+0xa2c/0x1d70
       lock_acquire+0xdc/0x228
       __mutex_lock+0x8c/0x800
       mutex_lock_nested+0x1c/0x28
       drm_gem_shmem_purge+0x20/0x40
       panfrost_gem_shrinker_scan+0xc0/0x180 [panfrost]
       do_shrink_slab+0x208/0x500
       shrink_slab+0x10c/0x2c0
       shrink_node+0x28c/0x4d8
       balance_pgdat+0x2c8/0x570
       kswapd+0x22c/0x638
       kthread+0x128/0x130
       ret_from_fork+0x10/0x18

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
                               lock(&shmem->pages_lock);
                               lock(fs_reclaim);
  lock(&shmem->pages_lock);

 *** DEADLOCK ***

3 locks held by kswapd0/171:
 #0: 00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40
 #1: 00000000ceb37808 (shrinker_rwsem){++++}, at: shrink_slab+0xbc/0x2c0
 #2: 00000000f31efa81 (&pfdev->shrinker_lock){+.+.}, at: panfrost_gem_shrinker_scan+0x34/0x180 [panfrost]

Fixes: 17acb9f35e ("drm/shmem: Add madvise state and purge helpers")
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Steven Price <steven.price@arm.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-6-robh@kernel.org
2019-08-23 11:54:45 -05:00
Rob Herring 17acb9f35e drm/shmem: Add madvise state and purge helpers
Add support to the shmem GEM helpers for tracking madvise state and
purging pages. This is based on the msm implementation.

The BO provides a list_head, but the list management is handled outside
of the shmem helpers as there are different locking requirements.

Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Eric Anholt <eric@anholt.net>
Acked-by: Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190805143358.21245-1-robh@kernel.org
2019-08-08 15:54:10 -06:00
Noralf Trønnes 2194a63a81 drm: Add library for shmem backed GEM objects
This adds a library for shmem backed GEM objects.

v8:
- export drm_gem_shmem_create_with_handle
- call mapping_set_gfp_mask to set default zone to GFP_HIGHUSER
- Add helper drm_gem_shmem_get_pages_sgt()

v7:
- Use write-combine for mmap instead. This is the more common
  case. (robher)

v6:
- Fix uninitialized variable issue in an error path (anholt).
- Add a drm_gem_shmem_vm_open() to the fops to get proper refcounting
  of the pages (anholt).

v5:
- Drop drm_gem_shmem_prime_mmap() (Daniel Vetter)
- drm_gem_shmem_mmap(): Subtract drm_vma_node_start() to get the real
  vma->vm_pgoff
- drm_gem_shmem_fault(): Use vmf->pgoff now that vma->vm_pgoff is correct

v4:
- Drop cache modes (Thomas Hellstrom)
- Add a GEM attached vtable

v3:
- Grammar (Sam Ravnborg)
- s/drm_gem_shmem_put_pages_unlocked/drm_gem_shmem_put_pages_locked/
  (Sam Ravnborg)
- Add debug output in error path (Sam Ravnborg)

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190313004344.24169-1-robh@kernel.org
2019-03-14 12:06:44 -07:00