In case MMIO size is bigger than 4G and peer2peer DMA goes
through host bridge, we trigger a code path that assigns the
total linked IOVA (which is greater than 4G) to mapped_len.
Previously, `mapped_len` was declared as 32-bit `unsigned int`.
When accumulating `size_t` lengths, this leads to a silent wrap-around.
This truncation causes truncated lengths to be passed to functions
like `fill_sg_entry()`.
Fix this by changing `mapped_len` to `size_t` (64-bit). While
at it, fix similar potential overflow issues in `calc_sg_nents`
by using `size_t` for `nents` and checking against `UINT_MAX`
and using `unsigned int` for the loop iterator in `fill_sg_entry`
to match.
Fixes: 3aa31a8bb11e ("dma-buf: provide phys_vec to scatter-gather mapping routine")
Cc: stable(a)vger.kernel.org
Cc: iommu(a)lists.linux.dev
Reviewed-by: Pranjal Shrivastava <praan(a)google.com>
Signed-off-by: David Hu <xuehaohu(a)google.com>
---
Changes in v5:
- Removed WARN_ON_ONCE from calc_sg_nents() to avoid log noise (Jason).
- Added explicit check for `!nents` in dma_buf_phys_vec_to_sgt() to
cleanly return -EINVAL on overflow (Jason).
Changes in v4:
- Added WARN_ON_ONCE() to the nents overflow check to prevent silent
failures (Claude Bot).
Changes in v3:
- Removed leftover sentence fragment from the commit message.
- Kept `nents = 0` initialization (previously stated as removed in the
v2 changelog) as it is strictly required for the `+=` accumulation
loop in `calc_sg_nents()`.
Changes in v2:
- Fixed 'IVOA' -> 'IOVA' typo and expanded commit message (Claude Bot).
- Added Reverse Xmas tree formatting (Pranjal).
- Folded in extra bounds checking for calc_sg_nents() (Pranjal).
- Folded in type consistency fix for fill_sg_entry() (Pranjal).
drivers/dma-buf/dma-buf-mapping.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/dma-buf/dma-buf-mapping.c b/drivers/dma-buf/dma-buf-mapping.c
index 794acff2546a..607b7998463d 100644
--- a/drivers/dma-buf/dma-buf-mapping.c
+++ b/drivers/dma-buf/dma-buf-mapping.c
@@ -10,7 +10,7 @@ static struct scatterlist *fill_sg_entry(struct scatterlist *sgl, size_t length,
dma_addr_t addr)
{
unsigned int len, nents;
- int i;
+ unsigned int i;
nents = DIV_ROUND_UP(length, UINT_MAX);
for (i = 0; i < nents; i++) {
@@ -36,7 +36,7 @@ static unsigned int calc_sg_nents(struct dma_iova_state *state,
struct phys_vec *phys_vec, size_t nr_ranges,
size_t size)
{
- unsigned int nents = 0;
+ size_t nents = 0;
size_t i;
if (!state || !dma_use_iova(state)) {
@@ -51,6 +51,9 @@ static unsigned int calc_sg_nents(struct dma_iova_state *state,
nents = DIV_ROUND_UP(size, UINT_MAX);
}
+ if (nents > UINT_MAX)
+ return 0;
+
return nents;
}
@@ -95,9 +98,10 @@ struct sg_table *dma_buf_phys_vec_to_sgt(struct dma_buf_attachment *attach,
size_t nr_ranges, size_t size,
enum dma_data_direction dir)
{
- unsigned int nents, mapped_len = 0;
struct dma_buf_dma *dma;
struct scatterlist *sgl;
+ size_t mapped_len = 0;
+ unsigned int nents;
dma_addr_t addr;
size_t i;
int ret;
@@ -133,6 +137,11 @@ struct sg_table *dma_buf_phys_vec_to_sgt(struct dma_buf_attachment *attach,
}
nents = calc_sg_nents(dma->state, phys_vec, nr_ranges, size);
+ if (!nents) {
+ ret = -EINVAL;
+ goto err_free_state;
+ }
+
ret = sg_alloc_table(&dma->sgt, nents, GFP_KERNEL | __GFP_ZERO);
if (ret)
goto err_free_state;
--
2.54.0.929.g9b7fa37559-goog
Most of this patch series has already been pushed upstream, this is just
the second half of the patch series that has not been pushed yet + some
additional changes which were required to implement changes requested by
the mailing list. This patch series is originally from Asahi, previously
posted by Daniel Almeida.
The previous version of the patch series can be found here:
https://patchwork.freedesktop.org/series/164580/
Branch with patches applied available here:
https://gitlab.freedesktop.org/lyudess/linux/-/commits/rust/gem-shmem
This patch series applies on top of drm-rust-next
Patch-series wide changes since V15:
* Fix some major rebasing errors I somehow didn't notice :(
* Drop the dependency on LazyInit, use the trick that Alice suggested
instead.
* Fix dependency ordering so that Tyr can get the vmap stuff first
without the other bits.
Lyude Paul (6):
rust: drm: gem/shmem: Add DmaResvGuard helper
rust: drm: gem: Add vmap functions to shmem bindings
rust: sync: Add SetOnce::reset()
rust: gem: shmem: Fix Default implementation for ObjectConfig
rust: faux: Allow retrieving a bound Device
rust: drm: gem: Introduce shmem::Object::sg_table()
rust/kernel/drm/gem/shmem.rs | 507 ++++++++++++++++++++++++++++++++++-
rust/kernel/faux.rs | 7 +-
rust/kernel/sync/set_once.rs | 60 ++++-
3 files changed, 552 insertions(+), 22 deletions(-)
base-commit: b78dab829760aee9b83f5cf15550a0fe36c6f4b0
--
2.54.0
Experience the excitement of Geometry Dash https://geometry-online.io, a thrilling platformer that combines music, speed, and precision. Race through dazzling neon environments, avoid dangerous geometric obstacles, and synchronize your movements with the rhythm. Every level offers a fresh challenge that will push your reflexes and timing to their limits.
In case MMIO size is bigger than 4G and peer2peer DMA goes
through host bridge, we trigger a code path that assigns the
total linked IOVA (which is greater than 4G) to mapped_len.
Previously, `mapped_len` was declared as 32-bit `unsigned int`.
When accumulating `size_t` lengths, this leads to a silent wrap-around.
This truncation causes truncated lengths to be passed to functions
like `fill_sg_entry()`.
Fix this by changing `mapped_len` to `size_t` (64-bit). While
at it, fix similar potential overflow issues in `calc_sg_nents`
by using `size_t` for `nents` and checking against `UINT_MAX`
and using `unsigned int` for the loop iterator in `fill_sg_entry`
to match.
Fixes: 3aa31a8bb11e ("dma-buf: provide phys_vec to scatter-gather mapping routine")
Cc: stable(a)vger.kernel.org
Cc: iommu(a)lists.linux.dev
Reviewed-by: Pranjal Shrivastava <praan(a)google.com>
Signed-off-by: David Hu <xuehaohu(a)google.com>
---
Changes in v4:
- Added WARN_ON_ONCE() to the nents overflow check to prevent silent
failures (Claude Bot).
Changes in v3:
- Removed leftover sentence fragment from the commit message.
- Kept `nents = 0` initialization (previously stated as removed in the
v2 changelog) as it is strictly required for the `+=` accumulation
loop in `calc_sg_nents()`.
Changes in v2:
- Fixed 'IVOA' -> 'IOVA' typo and expanded commit message (Claude Bot).
- Added Reverse Xmas tree formatting (Pranjal).
- Folded in extra bounds checking for calc_sg_nents() (Pranjal).
- Folded in type consistency fix for fill_sg_entry() (Pranjal).
drivers/dma-buf/dma-buf-mapping.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/dma-buf/dma-buf-mapping.c b/drivers/dma-buf/dma-buf-mapping.c
index 794acff2546a..1aabc0ee70bb 100644
--- a/drivers/dma-buf/dma-buf-mapping.c
+++ b/drivers/dma-buf/dma-buf-mapping.c
@@ -10,7 +10,7 @@ static struct scatterlist *fill_sg_entry(struct scatterlist *sgl, size_t length,
dma_addr_t addr)
{
unsigned int len, nents;
- int i;
+ unsigned int i;
nents = DIV_ROUND_UP(length, UINT_MAX);
for (i = 0; i < nents; i++) {
@@ -36,7 +36,7 @@ static unsigned int calc_sg_nents(struct dma_iova_state *state,
struct phys_vec *phys_vec, size_t nr_ranges,
size_t size)
{
- unsigned int nents = 0;
+ size_t nents = 0;
size_t i;
if (!state || !dma_use_iova(state)) {
@@ -51,6 +51,9 @@ static unsigned int calc_sg_nents(struct dma_iova_state *state,
nents = DIV_ROUND_UP(size, UINT_MAX);
}
+ if (WARN_ON_ONCE(nents > UINT_MAX))
+ return 0;
+
return nents;
}
@@ -95,9 +98,10 @@ struct sg_table *dma_buf_phys_vec_to_sgt(struct dma_buf_attachment *attach,
size_t nr_ranges, size_t size,
enum dma_data_direction dir)
{
- unsigned int nents, mapped_len = 0;
struct dma_buf_dma *dma;
struct scatterlist *sgl;
+ size_t mapped_len = 0;
+ unsigned int nents;
dma_addr_t addr;
size_t i;
int ret;
--
2.54.0.929.g9b7fa37559-goog
The reason for this is to properly support the spi nor chip on the
Jetson Xavier NX module. Prior to this, it would time out on all
transfers and sometimes even trigger a cbb fault, locking up the entire
unit. With this, reading and writing to the flash memory works as
expected.
This also fixes the tegra210-quad spi driver to properly use the dma
memory space instead of the spi controllers. Without this, enabling dma
on the controllers results in mmu faults.
The driver change has only been tested on tegra210 / p3450 and tegra194
/ p3518 as that is the only available test platforms. Tegra234 and
Tegra241 should also be verified. I have p3766 for tegra234, but the
qspi flash memory is firewalled by mb1 on all publicly available
bootloaders, and no other spi devices are part of the devkit.
---
Changes in v2:
- Drop bindings patches
- Add patch to use dma memory space instead of the spi controllers when
dma is enabled.
- Drop iommu properties from final patch
- Link to v1: https://lore.kernel.org/r/20260515-tegra194-qspi-iommu-v1-0-57dfb63cd3d6@gm…
---
Aaron Kling (2):
spi: tegra210-quad: Allocate DMA memory for DMA engine
arm64: tegra: Enable DMA Support on Tegra194 QSPI
arch/arm64/boot/dts/nvidia/tegra194.dtsi | 4 ++++
drivers/spi/spi-tegra210-quad.c | 29 ++++++++++++++++++-----------
2 files changed, 22 insertions(+), 11 deletions(-)
---
base-commit: c1ecb239fa3456529a32255359fc78b69eb9d847
change-id: 20260515-tegra194-qspi-iommu-e4e4644d5fdf
Best regards,
--
Aaron Kling <webgeek1234(a)gmail.com>
The kerneldoc comment on dma_fence_init() and dma_fence_init64() describe
the legacy reason to pass an external lock as a need to prevent multiple
fences "from signaling out of order". However, this wording is a bit
misleading: a shared spinlock does not (and cannot) prevent the signaler
from signaling out of order. Signaling order is the driver's responsibility
regardless of whether the lock is shared or per-fence.
Reword both comments to better describe the legacy use cases where a
shared lock was needed.
Signed-off-by: Maíra Canal <mcanal(a)igalia.com>
---
v1 -> v2: https://lore.kernel.org/dri-devel/20260411185756.1887119-4-mcanal@igalia.co…
- Be more explicit about not allowing new users to use an external lock.
- De-duplicate the explanation in dma_fence_init64() by pointing to the
dma_fence_init() documentation.
v2 -> v3: https://lore.kernel.org/dri-devel/20260419134943.54833-2-mcanal@igalia.com/…
- Apply Christian's suggestion with small readability improvements.
---
drivers/dma-buf/dma-fence.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/drivers/dma-buf/dma-fence.c b/drivers/dma-buf/dma-fence.c
index b3bfa6943a8e..c7ea1e75d38a 100644
--- a/drivers/dma-buf/dma-fence.c
+++ b/drivers/dma-buf/dma-fence.c
@@ -1102,9 +1102,12 @@ __dma_fence_init(struct dma_fence *fence, const struct dma_fence_ops *ops,
* context and seqno are used for easy comparison between fences, allowing
* to check which fence is later by simply using dma_fence_later().
*
- * It is strongly discouraged to provide an external lock because this couples
- * lock and fence life time. This is only allowed for legacy use cases when
- * multiple fences need to be prevented from signaling out of order.
+ * External locks are a relic of legacy use cases that needed a shared lock
+ * to serialize signaling when no out-of-order signaling was possible through
+ * &dma_fence_ops.signaled. Drivers have abandoned this concept since the
+ * introduction of the callback, but the external lock is still around. New
+ * users MUST NOT use external locks, as they force the issuer to outlive all
+ * fences that reference the lock.
*/
void
dma_fence_init(struct dma_fence *fence, const struct dma_fence_ops *ops,
@@ -1129,9 +1132,8 @@ EXPORT_SYMBOL(dma_fence_init);
* Context and seqno are used for easy comparison between fences, allowing
* to check which fence is later by simply using dma_fence_later().
*
- * It is strongly discouraged to provide an external lock because this couples
- * lock and fence life time. This is only allowed for legacy use cases when
- * multiple fences need to be prevented from signaling out of order.
+ * New users MUST NOT use external locks. Check the documentation in
+ * dma_fence_init() to understand the motives behind the legacy use cases.
*/
void
dma_fence_init64(struct dma_fence *fence, const struct dma_fence_ops *ops,
--
2.54.0
Most of this patch series has already been pushed upstream, this is just
the second half of the patch series that has not been pushed yet + some
additional changes which were required to implement changes requested by
the mailing list. This patch series is originally from Asahi, previously
posted by Daniel Almeida.
The previous version of the patch series can be found here:
https://patchwork.freedesktop.org/series/164580/
Branch with patches applied available here:
https://gitlab.freedesktop.org/lyudess/linux/-/commits/rust/gem-shmem
This patch series applies on top of drm-rust-next with the following
dependencies applied:
https://lore.kernel.org/rust-for-linux/20260529173137.303717-1-lyude@redhat…
Lyude Paul (6):
rust: gem: shmem: Fix Default implementation for ObjectConfig
rust: drm: gem/shmem: Add DmaResvGuard helper
rust: drm: gem: Add vmap functions to shmem bindings
rust: faux: Allow retrieving a bound Device
drm/gem/shmem: Introduce __drm_gem_shmem_free_sgt_locked()
rust: drm: gem: Introduce shmem::Object::sg_table()
drivers/gpu/drm/drm_gem_shmem_helper.c | 32 +-
include/drm/drm_gem_shmem_helper.h | 1 +
rust/kernel/drm/gem/shmem.rs | 497 ++++++++++++++++++++++++-
rust/kernel/faux.rs | 7 +-
4 files changed, 512 insertions(+), 25 deletions(-)
base-commit: 0e42ec83d46ab8877d38d37493328ed7d1a24de8
prerequisite-patch-id: c8ade07eec6e9c9e875800b114137c459d362e4e
prerequisite-patch-id: c38da06dbc4cfd2589bf2e7e9f0ebaa4da521ddf
--
2.54.0
From: Mingyu Wang <25181214217(a)stu.xidian.edu.cn>
Syzkaller fuzzer triggered a kernel panic via a WARNING in
drm_prime_destroy_file_private() due to a non-empty prime rb_tree.
The root cause is a complete lack of synchronization in the teardown
path. While the import path (drm_gem_prime_fd_to_handle) holds the
&file_priv->prime.lock during lookup and insertion, the deletion path
(drm_prime_remove_buf_handle) traverses and mutates both the 'handles'
and 'dmabufs' rb_trees without acquiring any mutex.
When multiple threads concurrently close GEM handles or interleave import
and close operations, the pointers and balance states of the rb_tree
nodes get corrupted. As a result, certain members are erased from one
tree but remain orphaned in the other. Upon process exit, the final
sanity check triggers the WARNING.
[ 448.919314][T19739] ------------[ cut here ]------------
[ 448.945387][T19739] WARNING: CPU: 0 PID: 19739 at drivers/gpu/drm/drm_prime.c:223 drm_prime_destroy_file_private+0x43/0x60
...
[ 449.056535][T19739] Call Trace:
[ 449.056544][T19739] <TASK>
[ 449.056553][T19739] drm_file_free.part.0+0x805/0xcf0
[ 449.056652][T19739] drm_close_helper.isra.0+0x183/0x1f0
[ 449.056677][T19739] drm_release+0x1ab/0x360
[ 449.056719][T19739] __fput+0x402/0xb50
[ 449.056783][T19739] task_work_run+0x16b/0x260
[ 449.056883][T19739] exit_to_user_mode_loop+0xf9/0x130
[ 449.056931][T19739] do_syscall_64+0x424/0xfa0
[ 449.056977][T19739] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 449.057268][T19739] </TASK>
[ 449.057295][T19739] Kernel panic - not syncing: kernel: panic_on_warn set ...
Fix this by acquiring the prime_fpriv->lock mutex around the rb_tree
lookup and erasure logic. To respect the locking rules and avoid potential
deadlocks with driver-specific memory cleanups, assign the target node to
a temporary pointer and defer the dma_buf_put() and kfree() operations
until after the mutex is safely dropped.
Fixes: ea2aa97ca37a ("drm/gem: Fix GEM handle release errors")
Cc: stable(a)vger.kernel.org
Signed-off-by: Mingyu Wang <25181214217(a)stu.xidian.edu.cn>
---
drivers/gpu/drm/drm_prime.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 9b44c78cd77f..26319c638e0f 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -190,6 +190,9 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
uint32_t handle)
{
struct rb_node *rb;
+ struct drm_prime_member *found = NULL;
+
+ mutex_lock(&prime_fpriv->lock);
rb = prime_fpriv->handles.rb_node;
while (rb) {
@@ -200,8 +203,7 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
rb_erase(&member->handle_rb, &prime_fpriv->handles);
rb_erase(&member->dmabuf_rb, &prime_fpriv->dmabufs);
- dma_buf_put(member->dma_buf);
- kfree(member);
+ found = member;
break;
} else if (member->handle < handle) {
rb = rb->rb_right;
@@ -209,6 +211,13 @@ void drm_prime_remove_buf_handle(struct drm_prime_file_private *prime_fpriv,
rb = rb->rb_left;
}
}
+ mutex_unlock(&prime_fpriv->lock);
+
+ /* Defer resource release outside the mutex to prevent deadlocks */
+ if (found) {
+ dma_buf_put(found->dma_buf);
+ kfree(found);
+ }
}
void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv)
--
2.34.1
When dumping IB contents from a hung job, amdgpu_devcoredump_format()
acquires the VM root PD's reservation lock via amdgpu_vm_lock_by_pasid()
and then, for each IB referenced by the job, calls amdgpu_bo_reserve()
on the BO that backs the IB. Both reservations are taken on
reservation_ww_class_mutex objects but neither uses a ww_acquire_ctx,
which trips lockdep:
WARNING: possible recursive locking detected
--------------------------------------------
kworker/u128:0 is trying to acquire lock:
ffff88838b16e1f0 (reservation_ww_class_mutex){+.+.}-{4:4},
at: amdgpu_devcoredump_format+0x1594/0x23f0 [amdgpu]
but task is already holding lock:
ffff8882f82681f0 (reservation_ww_class_mutex){+.+.}-{4:4},
at: amdgpu_devcoredump_format+0x1594/0x23f0 [amdgpu]
Possible unsafe locking scenario:
CPU0
----
lock(reservation_ww_class_mutex);
lock(reservation_ww_class_mutex);
*** DEADLOCK ***
May be due to missing lock nesting notation
Workqueue: events_unbound amdgpu_devcoredump_deferred_work [amdgpu]
Call Trace:
__ww_mutex_lock.constprop.0
ww_mutex_lock
amdgpu_bo_reserve
amdgpu_devcoredump_format+0x1594 [amdgpu]
amdgpu_devcoredump_deferred_work+0xea [amdgpu]
process_one_work
worker_thread
kthread
The two reservations are on different BOs in the captured trace, so the
splat is a lockdep-correctness warning, not an observed deadlock. It
becomes a real self-deadlock whenever the IB BO shares its dma_resv
with the root PD (the always-valid case, see
amdgpu_vm_is_bo_always_valid()): amdgpu_bo_reserve(abo) re-acquires the
same ww_mutex without a ticket and blocks forever.
With amdgpu.gpu_recovery=0 the timeout handler refires every ~2 s and
each invocation produces this splat, drowning the kernel ring buffer.
Fix it by collecting the per-IB BO references under the root PD's
reservation, then releasing the root before reserving each IB BO
individually. The walk over the VM mapping tree must remain under the
root lock (mappings can be torn down without it), but the actual
content copies do not need to nest inside it. Each per-IB reservation
is now an independent top-level acquire, eliminating the nested
ww_mutex.
The collect/release logic is factored out into two small helpers
(amdgpu_devcoredump_collect_ib_refs / amdgpu_devcoredump_release_ib_refs)
to keep the main function's indentation reasonable.
This also fixes a BO refcount leak in the original code: when
amdgpu_bo_reserve() failed, control jumped to free_ib_content without
running amdgpu_bo_unref(). In the new structure the per-IB BO refs
are released unconditionally in the cleanup helper.
Reproducer (~150 LoC libdrm_amdgpu): submit a single GFX IB containing
PACKET3_INDIRECT_BUFFER chained at GPU VA 0 and wait for the fence.
The TDR fires within ~10 s and the deferred coredump worker produces
the splat above on every invocation.
Fixes: 7b15fc2d1f1a ("drm/amdgpu: dump job ibs in the devcoredump")
Cc: stable(a)vger.kernel.org # 7.1
Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov(a)gmail.com>
---
.../gpu/drm/amd/amdgpu/amdgpu_dev_coredump.c | 147 +++++++++++++-----
1 file changed, 110 insertions(+), 37 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dev_coredump.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dev_coredump.c
index d386bc775d03..f6bb968de756 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dev_coredump.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dev_coredump.c
@@ -207,6 +207,72 @@ static void amdgpu_devcoredump_fw_info(struct amdgpu_device *adev,
}
}
+struct amdgpu_devcoredump_ib_ref {
+ struct amdgpu_bo *bo;
+ u64 offset;
+};
+
+/*
+ * Walk the VM's mapping tree under the root PD's reservation to obtain the BO
+ * that backs each IB and pin it with a refcount. The root PD reservation is
+ * dropped before this function returns; the caller can then reserve each IB
+ * BO individually without nesting ww_mutex acquires on
+ * reservation_ww_class_mutex.
+ *
+ * Returns an array of num_ibs entries (each ib_refs[i].bo may be NULL if its
+ * mapping was not found), or NULL on allocation failure / VM lookup failure.
+ * The caller must release the BO refs and free the array.
+ */
+static struct amdgpu_devcoredump_ib_ref *
+amdgpu_devcoredump_collect_ib_refs(struct amdgpu_device *adev,
+ struct amdgpu_coredump_info *coredump)
+{
+ struct amdgpu_devcoredump_ib_ref *ib_refs;
+ struct amdgpu_bo_va_mapping *mapping;
+ struct amdgpu_bo *root;
+ struct amdgpu_vm *vm;
+ u64 va_start;
+
+ ib_refs = kcalloc(coredump->num_ibs, sizeof(*ib_refs), GFP_KERNEL);
+ if (!ib_refs)
+ return NULL;
+
+ vm = amdgpu_vm_lock_by_pasid(adev, &root, coredump->pasid);
+ if (!vm) {
+ kfree(ib_refs);
+ return NULL;
+ }
+
+ for (int i = 0; i < coredump->num_ibs; i++) {
+ va_start = coredump->ibs[i].gpu_addr & AMDGPU_GMC_HOLE_MASK;
+ mapping = amdgpu_vm_bo_lookup_mapping(vm, va_start / AMDGPU_GPU_PAGE_SIZE);
+ if (!mapping)
+ continue;
+
+ ib_refs[i].bo = amdgpu_bo_ref(mapping->bo_va->base.bo);
+ ib_refs[i].offset = va_start -
+ mapping->start * AMDGPU_GPU_PAGE_SIZE;
+ }
+
+ amdgpu_bo_unreserve(root);
+ amdgpu_bo_unref(&root);
+
+ return ib_refs;
+}
+
+static void
+amdgpu_devcoredump_release_ib_refs(struct amdgpu_devcoredump_ib_ref *ib_refs,
+ int num_ibs)
+{
+ if (!ib_refs)
+ return;
+
+ for (int i = 0; i < num_ibs; i++)
+ if (ib_refs[i].bo)
+ amdgpu_bo_unref(&ib_refs[i].bo);
+ kfree(ib_refs);
+}
+
static ssize_t
amdgpu_devcoredump_format(char *buffer, size_t count, struct amdgpu_coredump_info *coredump)
{
@@ -214,13 +280,11 @@ amdgpu_devcoredump_format(char *buffer, size_t count, struct amdgpu_coredump_inf
struct drm_printer p;
struct drm_print_iterator iter;
struct amdgpu_vm_fault_info *fault_info;
- struct amdgpu_bo_va_mapping *mapping;
struct amdgpu_ip_block *ip_block;
struct amdgpu_res_cursor cursor;
- struct amdgpu_bo *abo, *root;
- uint64_t va_start, offset;
+ struct amdgpu_bo *abo;
+ uint64_t offset;
struct amdgpu_ring *ring;
- struct amdgpu_vm *vm;
u32 *ib_content;
uint8_t *kptr;
int ver, i, j, r;
@@ -343,43 +407,52 @@ amdgpu_devcoredump_format(char *buffer, size_t count, struct amdgpu_coredump_inf
drm_printf(&p, "VRAM is lost due to GPU reset!\n");
if (coredump->num_ibs) {
- /* Don't try to lookup the VM or map the BOs when calculating the
- * size required to store the devcoredump.
+ struct amdgpu_devcoredump_ib_ref *ib_refs = NULL;
+
+ /*
+ * Snapshot per-IB BO references under the root PD's reservation,
+ * then release the root before reserving each IB BO individually
+ * to copy its contents.
+ *
+ * Reserving an IB BO while the root PD is still reserved would
+ * be a nested ww_mutex acquire on reservation_ww_class_mutex
+ * without a ww_acquire_ctx, which trips lockdep's recursive-
+ * locking check and self-deadlocks for IB BOs that share their
+ * dma_resv with the root PD (always-valid BOs).
+ *
+ * Skip lookup/reservation entirely on the sizing pass: it does
+ * not write IB content, and the size estimate doesn't depend on
+ * whether the BOs are reachable.
*/
- if (sizing_pass)
- vm = NULL;
- else
- vm = amdgpu_vm_lock_by_pasid(adev, &root, coredump->pasid);
+ if (!sizing_pass)
+ ib_refs = amdgpu_devcoredump_collect_ib_refs(adev, coredump);
- for (int i = 0; i < coredump->num_ibs && (sizing_pass || vm); i++) {
+ for (int i = 0; i < coredump->num_ibs; i++) {
ib_content = kvmalloc_array(coredump->ibs[i].ib_size_dw, 4,
GFP_KERNEL);
if (!ib_content)
continue;
- /* vm=NULL can only happen when 'sizing_pass' is true. Skip to the
- * drm_printf() calls (ib_content doesn't need to be initialized
- * as its content won't be written anywhere).
- */
- if (!vm)
+ if (sizing_pass)
goto output_ib_content;
- va_start = coredump->ibs[i].gpu_addr & AMDGPU_GMC_HOLE_MASK;
- mapping = amdgpu_vm_bo_lookup_mapping(vm, va_start / AMDGPU_GPU_PAGE_SIZE);
- if (!mapping)
- goto free_ib_content;
+ if (!ib_refs || !ib_refs[i].bo)
+ goto output_ib_content;
+
+ abo = ib_refs[i].bo;
+ offset = ib_refs[i].offset;
- offset = va_start - (mapping->start * AMDGPU_GPU_PAGE_SIZE);
- abo = amdgpu_bo_ref(mapping->bo_va->base.bo);
r = amdgpu_bo_reserve(abo, false);
if (r)
- goto free_ib_content;
+ goto output_ib_content;
if (abo->flags & AMDGPU_GEM_CREATE_NO_CPU_ACCESS) {
off = 0;
- if (abo->tbo.resource->mem_type != TTM_PL_VRAM)
- goto unreserve_abo;
+ if (abo->tbo.resource->mem_type != TTM_PL_VRAM) {
+ amdgpu_bo_unreserve(abo);
+ goto output_ib_content;
+ }
amdgpu_res_first(abo->tbo.resource, offset,
coredump->ibs[i].ib_size_dw * 4,
@@ -395,8 +468,10 @@ amdgpu_devcoredump_format(char *buffer, size_t count, struct amdgpu_coredump_inf
r = ttm_bo_kmap(&abo->tbo, 0,
PFN_UP(abo->tbo.base.size),
&abo->kmap);
- if (r)
- goto unreserve_abo;
+ if (r) {
+ amdgpu_bo_unreserve(abo);
+ goto output_ib_content;
+ }
kptr = amdgpu_bo_kptr(abo);
kptr += offset;
@@ -406,21 +481,19 @@ amdgpu_devcoredump_format(char *buffer, size_t count, struct amdgpu_coredump_inf
amdgpu_bo_kunmap(abo);
}
+ amdgpu_bo_unreserve(abo);
+
output_ib_content:
drm_printf(&p, "\nIB #%d 0x%llx %d dw\n",
i, coredump->ibs[i].gpu_addr, coredump->ibs[i].ib_size_dw);
- for (int j = 0; j < coredump->ibs[i].ib_size_dw; j++)
- drm_printf(&p, "0x%08x\n", ib_content[j]);
-unreserve_abo:
- if (vm)
- amdgpu_bo_unreserve(abo);
-free_ib_content:
+ if (!sizing_pass && ib_refs && ib_refs[i].bo) {
+ for (int j = 0; j < coredump->ibs[i].ib_size_dw; j++)
+ drm_printf(&p, "0x%08x\n", ib_content[j]);
+ }
kvfree(ib_content);
}
- if (vm) {
- amdgpu_bo_unreserve(root);
- amdgpu_bo_unref(&root);
- }
+
+ amdgpu_devcoredump_release_ib_refs(ib_refs, coredump->num_ibs);
}
return count - iter.remain;
--
2.54.0