Commit Graph

4 Commits

Author SHA1 Message Date
Matthew Brost
ae482ec8cd
drm/xe: Add staging tree for VM binds
Concurrent VM bind staging and zapping of PTEs from a userptr notifier
do not work because the view of PTEs is not stable. VM binds cannot
acquire the notifier lock during staging, as memory allocations are
required. To resolve this race condition, use a staging tree for VM
binds that is committed only under the userptr notifier lock during the
final step of the bind. This ensures a consistent view of the PTEs in
the userptr notifier.

A follow up may only use staging for VM in fault mode as this is the
only mode in which the above race exists.

v3:
 - Drop zap PTE change (Thomas)
 - s/xe_pt_entry/xe_pt_entry_staging (Thomas)

Suggested-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: <stable@vger.kernel.org>
Fixes: e8babb280b ("drm/xe: Convert multiple bind ops into single job")
Fixes: a708f6501c ("drm/xe: Update PT layer with better error handling")
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250228073058.59510-5-thomas.hellstrom@linux.intel.com
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
(cherry picked from commit 6f39b0c5ef)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
2025-03-05 14:25:11 -05:00
Thomas Hellström
8cb92dc730 drm/xe/pt: Allow for stricter type- and range checking
Distinguish between xe_pt and the xe_pt_dir subclass when
allocating and freeing. Also use a fixed-size array for the
xe_pt_dir page entries to make life easier for dynamic range-
checkers. Finally rename the page-directory child pointer array
to "children".

While no functional change, this fixes ubsan splats similar to:

[   51.463021] ------------[ cut here ]------------
[   51.463022] UBSAN: array-index-out-of-bounds in drivers/gpu/drm/xe/xe_pt.c:47:9
[   51.463023] index 0 is out of range for type 'xe_ptw *[*]'
[   51.463024] CPU: 5 PID: 2778 Comm: xe_vm Tainted: G     U             6.8.0-rc1+ #218
[   51.463026] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
[   51.463027] Call Trace:
[   51.463028]  <TASK>
[   51.463029]  dump_stack_lvl+0x47/0x60
[   51.463030]  __ubsan_handle_out_of_bounds+0x95/0xd0
[   51.463032]  xe_pt_destroy+0xa5/0x150 [xe]
[   51.463088]  __xe_pt_unbind_vma+0x36c/0x9b0 [xe]
[   51.463144]  xe_vm_unbind+0xd8/0x580 [xe]
[   51.463204]  ? drm_exec_prepare_obj+0x3f/0x60 [drm_exec]
[   51.463208]  __xe_vma_op_execute+0x5da/0x910 [xe]
[   51.463268]  ? __drm_gpuvm_sm_unmap+0x1cb/0x220 [drm_gpuvm]
[   51.463272]  ? radix_tree_node_alloc.constprop.0+0x89/0xc0
[   51.463275]  ? drm_gpuva_it_remove+0x1f3/0x2a0 [drm_gpuvm]
[   51.463279]  ? drm_gpuva_remove+0x2f/0xc0 [drm_gpuvm]
[   51.463283]  xe_vm_bind_ioctl+0x1a55/0x20b0 [xe]
[   51.463344]  ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe]
[   51.463414]  drm_ioctl_kernel+0xb6/0x120
[   51.463416]  drm_ioctl+0x287/0x4e0
[   51.463418]  ? __pfx_xe_vm_bind_ioctl+0x10/0x10 [xe]
[   51.463481]  __x64_sys_ioctl+0x94/0xd0
[   51.463484]  do_syscall_64+0x86/0x170
[   51.463486]  ? syscall_exit_to_user_mode+0x7d/0x200
[   51.463488]  ? do_syscall_64+0x96/0x170
[   51.463490]  ? do_syscall_64+0x96/0x170
[   51.463492]  entry_SYSCALL_64_after_hwframe+0x6e/0x76
[   51.463494] RIP: 0033:0x7f246bfe817d
[   51.463498] Code: 04 25 28 00 00 00 48 89 45 c8 31 c0 48 8d 45 10 c7 45 b0 10 00 00 00 48 89 45 b8 48 8d 45 d0 48 89 45 c0 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1a 48 8b 45 c8 64 48 2b 04 25 28 00 00 00
[   51.463501] RSP: 002b:00007ffc1bd19ad0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[   51.463502] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f246bfe817d
[   51.463504] RDX: 00007ffc1bd19b60 RSI: 0000000040886445 RDI: 0000000000000003
[   51.463505] RBP: 00007ffc1bd19b20 R08: 0000000000000000 R09: 0000000000000000
[   51.463506] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc1bd19b60
[   51.463508] R13: 0000000040886445 R14: 0000000000000003 R15: 0000000000010000
[   51.463510]  </TASK>
[   51.463517] ---[ end trace ]---

v2
- Fix kerneldoc warning (Matthew Brost)

Fixes: dd08ebf6c3 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240209112655.4872-1-thomas.hellstrom@linux.intel.com
(cherry picked from commit 157261c58b)
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
2024-02-15 09:53:18 +01:00
Thomas Hellström
670e811d1f drm/xe: Update SPDX deprecated license identifier
The "GPL-2.0" SPDX license identifier is deprecated. Update the
code to use "GPL-2.0-only" instead. Choose this identifier over
"GPL-2.0-or-later" since it's the most restrictive of the two and it's
not fully clear that "GPL-2.0" also allows "GPL-2.0-or-later".

Cc: Francois Dugast <francois.dugast@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Francois Dugast <francois.dugast@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231107082440.7568-1-thomas.hellstrom@linux.intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
2023-12-21 11:43:34 -05:00
Matthew Brost
dd08ebf6c3 drm/xe: Introduce a new DRM driver for Intel GPUs
Xe, is a new driver for Intel GPUs that supports both integrated and
discrete platforms starting with Tiger Lake (first Intel Xe Architecture).

The code is at a stage where it is already functional and has experimental
support for multiple platforms starting from Tiger Lake, with initial
support implemented in Mesa (for Iris and Anv, our OpenGL and Vulkan
drivers), as well as in NEO (for OpenCL and Level0).

The new Xe driver leverages a lot from i915.

As for display, the intent is to share the display code with the i915
driver so that there is maximum reuse there. But it is not added
in this patch.

This initial work is a collaboration of many people and unfortunately
the big squashed patch won't fully honor the proper credits. But let's
get some git quick stats so we can at least try to preserve some of the
credits:

Co-developed-by: Matthew Brost <matthew.brost@intel.com>
Co-developed-by: Matthew Auld <matthew.auld@intel.com>
Co-developed-by: Matt Roper <matthew.d.roper@intel.com>
Co-developed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Co-developed-by: Francois Dugast <francois.dugast@intel.com>
Co-developed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Co-developed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Co-developed-by: Philippe Lecluse <philippe.lecluse@intel.com>
Co-developed-by: Nirmoy Das <nirmoy.das@intel.com>
Co-developed-by: Jani Nikula <jani.nikula@intel.com>
Co-developed-by: José Roberto de Souza <jose.souza@intel.com>
Co-developed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Co-developed-by: Dave Airlie <airlied@redhat.com>
Co-developed-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Co-developed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Co-developed-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
2023-12-12 14:05:48 -05:00