linux-stable.git/include/linux/dma-resv.h, branch v5.16.2

Merge tag 'drm-misc-next-2021-10-14' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

2021-11-05T03:50:15+00:00

drm-misc-next for 5.16:

UAPI Changes:

Cross-subsystem Changes:

Core Changes:
  - fbdev: Fix double-free, Remove unused scrolling acceleration
  - locking: improve logging for contented locks without backoff
  - dma-buf: Add dma_resv_for_each_fence iterator, and conversion of
    users

Driver Changes:
  - nouveau: Various code style improvements
  - bridge: HPD improvements for lt9611uxc, eDP aux-bus support for
    ps8640, lvds-codec data-mapping selection support
  - panels: Vivax TPC-9150, Innolux G070Y2-T02, LOGIC Technologies
    LTTD800480070-L2RT, Sharp LS060T1SX01,

Signed-off-by: Dave Airlie 

From: Maxime Ripard 
Link: https://patchwork.freedesktop.org/patch/msgid/20211014120452.2wicnt6hobu3kbwb@gilmour

dma-resv: Fix dma_resv_get_fences and dma_resv_copy_fences after conversion

2021-10-11T14:14:08+00:00

Cache the count of shared fences in the iterator to avoid dereferencing
the dma_resv_object outside the RCU protection. Otherwise iterator and its
users can observe an incosistent state which makes it impossible to use
safely. Such as:

<6> [187.517041] [IGT] gem_sync: executing
<7> [187.536343] i915 0000:00:02.0: [drm:i915_gem_context_create_ioctl [i915]] HW context 1 created
<7> [187.536793] i915 0000:00:02.0: [drm:i915_gem_context_create_ioctl [i915]] HW context 1 created
<6> [187.551235] [IGT] gem_sync: starting subtest basic-many-each
<1> [188.935462] BUG: kernel NULL pointer dereference, address: 0000000000000010
<1> [188.935485] #PF: supervisor write access in kernel mode
<1> [188.935495] #PF: error_code(0x0002) - not-present page
<6> [188.935504] PGD 0 P4D 0
<4> [188.935512] Oops: 0002 [#1] PREEMPT SMP NOPTI
<4> [188.935521] CPU: 2 PID: 1467 Comm: gem_sync Not tainted 5.15.0-rc4-CI-Patchwork_21264+ #1
<4> [188.935535] Hardware name:  /NUC6CAYB, BIOS AYAPLCEL.86A.0049.2018.0508.1356 05/08/2018
<4> [188.935546] RIP: 0010:dma_resv_get_fences+0x116/0x2d0
<4> [188.935560] Code: 10 85 c0 7f c9 be 03 00 00 00 e8 15 8b df ff eb bd e8 8e c6 ff ff eb b6 41 8b 04 24 49 8b 55 00 48 89 e7 8d 48 01 41 89 0c 24 <4c> 89 34 c2 e8 41 f2 ff ff 49 89 c6 48 85 c0 75 8c 48 8b 44 24 10
<4> [188.935583] RSP: 0018:ffffc900011dbcc8 EFLAGS: 00010202
<4> [188.935593] RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000000000001
<4> [188.935603] RDX: 0000000000000010 RSI: ffffffff822e343c RDI: ffffc900011dbcc8
<4> [188.935613] RBP: ffffc900011dbd48 R08: ffff88812d255bb8 R09: 00000000fffffffe
<4> [188.935623] R10: 0000000000000001 R11: 0000000000000000 R12: ffffc900011dbd44
<4> [188.935633] R13: ffffc900011dbd50 R14: ffff888113d29cc0 R15: 0000000000000000
<4> [188.935643] FS:  00007f68d17e9700(0000) GS:ffff888277900000(0000) knlGS:0000000000000000
<4> [188.935655] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4> [188.935665] CR2: 0000000000000010 CR3: 000000012d0a4000 CR4: 00000000003506e0
<4> [188.935676] Call Trace:
<4> [188.935685]  i915_gem_object_wait+0x1ff/0x410 [i915]
<4> [188.935988]  i915_gem_wait_ioctl+0xf2/0x2a0 [i915]
<4> [188.936272]  ? i915_gem_object_wait+0x410/0x410 [i915]
<4> [188.936533]  drm_ioctl_kernel+0xae/0x140
<4> [188.936546]  drm_ioctl+0x201/0x3d0
<4> [188.936555]  ? i915_gem_object_wait+0x410/0x410 [i915]
<4> [188.936820]  ? __fget_files+0xc2/0x1c0
<4> [188.936830]  ? __fget_files+0xda/0x1c0
<4> [188.936839]  __x64_sys_ioctl+0x6d/0xa0
<4> [188.936848]  do_syscall_64+0x3a/0xb0
<4> [188.936859]  entry_SYSCALL_64_after_hwframe+0x44/0xae

If the shared object has changed during the RCU unlocked period
callers will correctly handle the restart on the next iteration.

Signed-off-by: Tvrtko Ursulin 
Fixes: 96601e8a4755 ("dma-buf: use new iterator in dma_resv_copy_fences")
Fixes: d3c80698c9f5 ("dma-buf: use new iterator in dma_resv_get_fences v3")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4274
Cc: Christian König 
Cc: Daniel Vetter 
Cc: Sumit Semwal 
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20211008095007.972693-1-tvrtko.ursulin@linux.intel.com
Reviewed-by: Christian König 
Signed-off-by: Christian König

Merge tag 'drm-intel-gt-next-2021-10-08' of git://anongit.freedesktop.org/drm/drm-intel into drm-next

2021-10-11T08:09:39+00:00

UAPI Changes:

- Add uAPI for using PXP protected objects

  Mesa changes: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8064

- Add PCI IDs and LMEM discovery/placement uAPI for DG1

  Mesa changes: https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11584

- Disable engine bonding on Gen12+ except TGL, RKL and ADL-S

Cross-subsystem Changes:

- Merges 'tip/locking/wwmutex' branch (core kernel tip)
- "mei: pxp: export pavp client to me client bus"

Core Changes:

- Update ttm_move_memcpy for async use (Thomas)

Driver Changes:

- Enable GuC submission by default on DG1 (Matt B)
- Add PXP (Protected Xe Path) support for Gen12 integrated (Daniele,
  Sean, Anshuman)
  See "drm/i915/pxp: add PXP documentation" for details!
- Remove force_probe protection for ADL-S (Raviteja)
- Add base support for XeHP/XeHP SDV (Matt R, Stuart, Lucas)
- Handle DRI_PRIME=1 on Intel igfx + Intel dgfx hybrid graphics setup (Tvrtko)
- Use Transparent Hugepages when IOMMU is enabled (Tvrtko, Chris)
- Implement LMEM backup and restore for suspend / resume (Thomas)
- Report INSTDONE_GEOM values in error state for DG2 (Matt R)
- Add DG2-specific shadow register table (Matt R)
- Update Gen11/Gen12/XeHP shadow register tables (Matt R)
- Maintain backward-compatible nested batch behavior on TGL+ (Matt R)
- Add new LRI reg offsets for DG2 (Akeem)
- Initialize unused MOCS entries to device specific values (Ayaz)
- Track and use the correct UC MOCS index on Gen12 (Ayaz)
- Add separate MOCS table for Gen12 devices other than TGL/RKL (Ayaz)
- Simplify the locking and eliminate some RCU usage (Daniel)
- Add some flushing for the 64K GTT path (Matt A)
- Mark GPU wedging on driver unregister unrecoverable (Janusz)

- Major rework in the GuC codebase, simplify locking and add docs (Matt B)
- Add DG1 GuC/HuC firmwares (Daniele, Matt B)
- Remember to call i915_sw_fence_fini on guc_state.blocked (Matt A)
- Use "gt" forcewake domain name for error messages instead of "blitter" (Matt R)
- Drop now duplicate LMEM uAPI RFC kerneldoc section (Daniel)
- Fix early tracepoints for requests (Matt A)
- Use locked access to ctx->engines in set_priority (Daniel)
- Convert gen6/gen7/gen8 read operations to fwtable (Matt R)
- Drop gen11/gen12 specific mmio write handlers (Matt R)
- Drop gen11 specific mmio read handlers (Matt R)
- Use designated initializers for init/exit table (Kees)
- Fix syncmap memory leak (Matt B)
- Add pretty printing for buddy allocator state debug (Matt A)
- Fix potential error pointer dereference in pinned_context() (Dan)
- Remove IS_ACTIVE macro (Lucas)
- Static code checker fixes (Nathan)
- Clean up disabled warnings (Nathan)
- Increase timeout in i915_gem_contexts selftests 5x for GuC submission (Matt B)
- Ensure wa_init_finish() is called for ctx workaround list (Matt R)
- Initialize L3CC table in mocs init (Sreedhar, Ayaz, Ram)
- Get PM ref before accessing HW register (Vinay)
- Move __i915_gem_free_object to ttm_bo_destroy (Maarten)
- Deduplicate frequency dump on debugfs (Lucas)
- Make wa list per-gt (Venkata)
- Do not define dummy vma in stack (Venkata)
- Take pinning into account in __i915_gem_object_is_lmem (Matt B, Thomas)
- Do not report currently active engine when describing objects (Tvrtko)
- Fix pdfdocs build error by removing nested grid from GuC docs (Akira)
- Remove false warning from the rps worker (Tejas)
- Flush buffer pools on driver remove (Janusz)
- Fix runtime pm handling in i915_gem_shrink (Maarten)
- Rework TTM object initialization slightly (Thomas)
- Use fixed offset for PTEs location (Michal Wa)
- Verify result from CTB (de)register action and improve error messages (Michal Wa)
- Fix bug in user proto-context creation that leaked contexts (Matt B)

- Re-use Gen11 forcewake read functions on Gen12 (Matt R)
- Make shadow tables range-based (Matt R)
- Ditch the i915_gem_ww_ctx loop member (Thomas, Maarten)
- Use NULL instead of 0 where appropriate (Ville)
- Rename pci/debugfs functions to respect file prefix (Jani, Lucas)
- Drop guc_communication_enabled (Daniele)
- Selftest fixes (Thomas, Daniel, Matt A, Maarten)
- Clean up inconsistent indenting (Colin)
- Use direction definition DMA_BIDIRECTIONAL instead of
  PCI_DMA_BIDIRECTIONAL (Cai)
- Add "intel_" as prefix in set_mocs_index() (Ayaz)

From: Joonas Lahtinen 
Link: https://patchwork.freedesktop.org/patch/msgid/YWAO80MB2eyToYoy@jlahtine-mobl.ger.corp.intel.com
Signed-off-by: Dave Airlie

dma-buf: add dma_resv_for_each_fence v3

2021-10-07T12:49:11+00:00

A simpler version of the iterator to be used when the dma_resv object is
locked.

v2: fix index check here as well
v3: minor coding improvement, some documentation cleanup

Signed-off-by: Christian König 
Reviewed-by: Tvrtko Ursulin 
Link: https://patchwork.freedesktop.org/patch/msgid/20211006123609.2026-1-christian.koenig@amd.com

dma-buf: add dma_resv_for_each_fence_unlocked v8

2021-10-06T07:48:01+00:00

Abstract the complexity of iterating over all the fences
in a dma_resv object.

The new loop handles the whole RCU and retry dance and
returns only fences where we can be sure we grabbed the
right one.

v2: fix accessing the shared fences while they might be freed,
    improve kerneldoc, rename _cursor to _iter, add
    dma_resv_iter_is_exclusive, add dma_resv_iter_begin/end

v3: restructor the code, move rcu_read_lock()/unlock() into the
    iterator, add dma_resv_iter_is_restarted()

v4: fix NULL deref when no explicit fence exists, drop superflous
    rcu_read_lock()/unlock() calls.

v5: fix typos in the documentation

v6: fix coding error when excl fence is NULL

v7: one more logic fix

v8: fix index check in dma_resv_iter_is_exclusive()

Signed-off-by: Christian König 
Reviewed-by: Tvrtko Ursulin  (v7)
Link: https://patchwork.freedesktop.org/patch/msgid/20211005113742.1101-2-christian.koenig@amd.com

kernel/locking: Add context to ww_mutex_trylock()

2021-09-17T13:08:41+00:00

i915 will soon gain an eviction path that trylock a whole lot of locks
for eviction, getting dmesg failures like below:

  BUG: MAX_LOCK_DEPTH too low!
  turning off the locking correctness validator.
  depth: 48  max: 48!
  48 locks held by i915_selftest/5776:
   #0: ffff888101a79240 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x88/0x160
   #1: ffffc900009778c0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.63+0x39/0x1b0 [i915]
   #2: ffff88800cf74de8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.63+0x5f/0x1b0 [i915]
   #3: ffff88810c7f9e38 (&vm->mutex/1){+.+.}-{3:3}, at: i915_vma_pin_ww+0x1c4/0x9d0 [i915]
   #4: ffff88810bad5768 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
   #5: ffff88810bad60e8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
  ...
   #46: ffff88811964d768 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
   #47: ffff88811964e0e8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_gem_evict_something+0x110/0x860 [i915]
  INFO: lockdep is turned off.

Fixing eviction to nest into ww_class_acquire is a high priority, but
it requires a rework of the entire driver, which can only be done one
step at a time.

As an intermediate solution, add an acquire context to
ww_mutex_trylock, which allows us to do proper nesting annotations on
the trylocks, making the above lockdep splat disappear.

This is also useful in regulator_lock_nested, which may avoid dropping
regulator_nesting_mutex in the uncontended path, so use it there.

TTM may be another user for this, where we could lock a buffer in a
fastpath with list locks held, without dropping all locks we hold.

[peterz: rework actual ww_mutex_trylock() implementations]
Signed-off-by: Maarten Lankhorst 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://lkml.kernel.org/r/YUBGPdDDjKlxAuXJ@hirez.programming.kicks-ass.net

dma-resv: Give the docs a do-over

2021-08-30T19:37:59+00:00

Specifically document the new/clarified rules around how the shared
fences do not have any ordering requirements against the exclusive
fence.

But also document all the things a bit better, given how central
struct dma_resv to dynamic buffer management the docs have been very
inadequat.

- Lots more links to other pieces of the puzzle. Unfortunately
  ttm_buffer_object has no docs, so no links :-(

- Explain/complain a bit about dma_resv_locking_ctx(). I still don't
  like that one, but fixing the ttm call chains is going to be
  horrible. Plus we want to plug in real slowpath locking when we do
  that anyway.

- Main part of the patch is some actual docs for struct dma_resv.

Overall I think we still have a lot of bad naming in this area (e.g.
dma_resv.fence is singular, but contains the multiple shared fences),
but I think that's more indicative of how the semantics and rules are
just not great.

Another thing that's real awkard is how chaining exclusive fences
right now means direct dma_resv.exclusive_fence pointer access with an
rcu_assign_pointer. Not so great either.

v2:
- Fix a pile of typos (Matt, Jason)
- Hammer it in that breaking the rules leads to use-after-free issues
  around dma-buf sharing (Christian)

Reviewed-by: Christian König 
Cc: Jason Ekstrand 
Cc: Matthew Auld 
Reviewed-by: Matthew Auld 
Signed-off-by: Daniel Vetter 
Cc: Sumit Semwal 
Cc: "Christian König" 
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210805104705.862416-21-daniel.vetter@ffwll.ch

: correct a function name in kernel-doc

2021-06-29T16:09:24+00:00

Fix kernel-doc function name warning:

../include/linux/dma-resv.h:227: warning: expecting prototype for dma_resv_exclusive(). Prototype was for dma_resv_excl_fence() instead

Fixes: 6edbd6abb783d ("dma-buf: rename and cleanup dma_resv_get_excl v3")
Signed-off-by: Randy Dunlap 
Cc: Sumit Semwal 
Cc: Christian König 
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210628004012.6792-1-rdunlap@infradead.org

dma-buf: drop the _rcu postfix on function names v3

2021-06-06T09:19:51+00:00

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 
Reviewed-by: Jason Ekstrand 
Acked-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-7-christian.koenig@amd.com

dma-buf: rename dma_resv_get_excl_rcu to _unlocked

2021-06-06T09:19:30+00:00

That describes much better what the function is doing here.

Signed-off-by: Christian König 
Reviewed-by: Jason Ekstrand 
Acked-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20210602111714.212426-6-christian.koenig@amd.com