A bunch of fixes for 6.17:

- analogix_dp: devm_drm_bridge_alloc() error handling fix
   - gaudi: Memory deallocation fix
   - gpuvm: Documentation warning fix
   - hibmc: Various misc fixes
   - nouveau: Memory leak fixes, typos
   - panic: u64 division handling on 32 bits architecture fix
   - rockchip: Kconfig fix, register caching fix
   - rust: memory layout and safety fixes
   - tests: Endianness fixes
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 dlzDAYCq9KkxgD1kDNyqREp+WGbjOPTvq9XkkVJIcJKycVZjMqsCdmJrp91vn3XY
 JnmXql0Bfjcysmz0OfPIUJtjlS94RFVkGF7ZVlBhqvIosqjfyFN5GGaLKXZyMYQK
 aIBJ+DFEcA==
 =2Zvh
 -----END PGP SIGNATURE-----

Merge tag 'drm-misc-fixes-2025-08-21' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes

A bunch of fixes for 6.17:
  - analogix_dp: devm_drm_bridge_alloc() error handling fix
  - gaudi: Memory deallocation fix
  - gpuvm: Documentation warning fix
  - hibmc: Various misc fixes
  - nouveau: Memory leak fixes, typos
  - panic: u64 division handling on 32 bits architecture fix
  - rockchip: Kconfig fix, register caching fix
  - rust: memory layout and safety fixes
  - tests: Endianness fixes

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

From: Maxime Ripard <mripard@redhat.com>
Link: https://lore.kernel.org/r/20250821-economic-dandelion-rooster-c57fa9@houat

MAINTAINERS

@@ -8426,6 +8426,17 @@ T:	git https://gitlab.freedesktop.org/drm/misc/kernel.git
 F:	drivers/gpu/drm/scheduler/
 F:	include/drm/gpu_scheduler.h
 
+DRM GPUVM
+M:	Danilo Krummrich <dakr@kernel.org>
+R:	Matthew Brost <matthew.brost@intel.com>
+R:	Thomas Hellström <thomas.hellstrom@linux.intel.com>
+R:	Alice Ryhl <aliceryhl@google.com>
+L:	dri-devel@lists.freedesktop.org
+S:	Supported
+T:	git https://gitlab.freedesktop.org/drm/misc/kernel.git
+F:	drivers/gpu/drm/drm_gpuvm.c
+F:	include/drm/drm_gpuvm.h
+
 DRM LOG
 M:	Jocelyn Falempe <jfalempe@redhat.com>
 M:	Javier Martinez Canillas <javierm@redhat.com>
@@ -10655,7 +10666,8 @@ S:	Maintained
 F:	block/partitions/efi.*
 
 HABANALABS PCI DRIVER
-M:	Yaron Avizrat <yaron.avizrat@intel.com>
+M:	Koby Elbaz <koby.elbaz@intel.com>
+M:	Konstantin Sinyuk <konstantin.sinyuk@intel.com>
 L:	dri-devel@lists.freedesktop.org
 S:	Supported
 C:	irc://irc.oftc.net/dri-devel

drivers/accel/habanalabs/gaudi2/gaudi2.c

@@ -10437,7 +10437,7 @@ end:
 				(u64 *)(lin_dma_pkts_arr), DEBUGFS_WRITE64);
 	WREG32(sob_addr, 0);
 
-	kfree(lin_dma_pkts_arr);
+	kvfree(lin_dma_pkts_arr);
 
 	return rc;
 }

drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c

@@ -514,7 +514,7 @@ bool amdgpu_dmabuf_is_xgmi_accessible(struct amdgpu_device *adev,
 		return false;
 
 	if (drm_gem_is_imported(obj)) {
-		struct dma_buf *dma_buf = obj->dma_buf;
+		struct dma_buf *dma_buf = obj->import_attach->dmabuf;
 
 		if (dma_buf->ops != &amdgpu_dmabuf_ops)
 			/* No XGMI with non AMD GPUs */

drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c

@@ -317,7 +317,8 @@ static int amdgpu_gem_object_open(struct drm_gem_object *obj,
 	 */
 	if (!vm->is_compute_context || !vm->process_info)
 		return 0;
-	if (!drm_gem_is_imported(obj) || !dma_buf_is_dynamic(obj->dma_buf))
+	if (!drm_gem_is_imported(obj) ||
+	    !dma_buf_is_dynamic(obj->import_attach->dmabuf))
 		return 0;
 	mutex_lock_nested(&vm->process_info->lock, 1);
 	if (!WARN_ON(!vm->process_info->eviction_fence)) {

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c

@@ -1283,7 +1283,7 @@ int amdgpu_vm_bo_update(struct amdgpu_device *adev, struct amdgpu_bo_va *bo_va,
 		struct drm_gem_object *obj = &bo->tbo.base;
 
 		if (drm_gem_is_imported(obj) && bo_va->is_xgmi) {
-			struct dma_buf *dma_buf = obj->dma_buf;
+			struct dma_buf *dma_buf = obj->import_attach->dmabuf;
 			struct drm_gem_object *gobj = dma_buf->priv;
 			struct amdgpu_bo *abo = gem_to_amdgpu_bo(gobj);
 

drivers/gpu/drm/bridge/analogix/analogix_dp_core.c

@@ -1474,8 +1474,8 @@ analogix_dp_probe(struct device *dev, struct analogix_dp_plat_data *plat_data)
 
 	dp = devm_drm_bridge_alloc(dev, struct analogix_dp_device, bridge,
 				   &analogix_dp_bridge_funcs);
-	if (!dp)
+	if (IS_ERR(dp))
-		return ERR_PTR(-ENOMEM);
+		return ERR_CAST(dp);
 
 	dp->dev = &pdev->dev;
 	dp->dpms_mode = DRM_MODE_DPMS_OFF;

drivers/gpu/drm/drm_gpuvm.c

@@ -2432,6 +2432,8 @@ static const struct drm_gpuvm_ops lock_ops = {
  *
  * The expected usage is:
  *
+ * .. code-block:: c
+ *
  *    vm_bind {
  *        struct drm_exec exec;
  *

drivers/gpu/drm/drm_panic_qr.rs

@@ -381,6 +381,26 @@ struct DecFifo {
     len: usize,
 }
 
+// On arm32 architecture, dividing an `u64` by a constant will generate a call
+// to `__aeabi_uldivmod` which is not present in the kernel.
+// So use the multiply by inverse method for this architecture.
+fn div10(val: u64) -> u64 {
+    if cfg!(target_arch = "arm") {
+        let val_h = val >> 32;
+        let val_l = val & 0xFFFFFFFF;
+        let b_h: u64 = 0x66666666;
+        let b_l: u64 = 0x66666667;
+
+        let tmp1 = val_h * b_l + ((val_l * b_l) >> 32);
+        let tmp2 = val_l * b_h + (tmp1 & 0xffffffff);
+        let tmp3 = val_h * b_h + (tmp1 >> 32) + (tmp2 >> 32);
+
+        tmp3 >> 2
+    } else {
+        val / 10
+    }
+}
+
 impl DecFifo {
     fn push(&mut self, data: u64, len: usize) {
         let mut chunk = data;
@@ -389,7 +409,7 @@ impl DecFifo {
         }
         for i in 0..len {
             self.decimals[i] = (chunk % 10) as u8;
-            chunk /= 10;
+            chunk = div10(chunk);
         }
         self.len += len;
     }

drivers/gpu/drm/hisilicon/hibmc/dp/dp_link.c

@@ -325,6 +325,17 @@ static int hibmc_dp_link_downgrade_training_eq(struct hibmc_dp_dev *dp)
 	return hibmc_dp_link_reduce_rate(dp);
 }
 
+static void hibmc_dp_update_caps(struct hibmc_dp_dev *dp)
+{
+	dp->link.cap.link_rate = dp->dpcd[DP_MAX_LINK_RATE];
+	if (dp->link.cap.link_rate > DP_LINK_BW_8_1 || !dp->link.cap.link_rate)
+		dp->link.cap.link_rate = DP_LINK_BW_8_1;
+
+	dp->link.cap.lanes = dp->dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
+	if (dp->link.cap.lanes > HIBMC_DP_LANE_NUM_MAX)
+		dp->link.cap.lanes = HIBMC_DP_LANE_NUM_MAX;
+}
+
 int hibmc_dp_link_training(struct hibmc_dp_dev *dp)
 {
 	struct hibmc_dp_link *link = &dp->link;
@@ -334,8 +345,7 @@ int hibmc_dp_link_training(struct hibmc_dp_dev *dp)
 	if (ret)
 		drm_err(dp->dev, "dp aux read dpcd failed, ret: %d\n", ret);
 
-	dp->link.cap.link_rate = dp->dpcd[DP_MAX_LINK_RATE];
+	hibmc_dp_update_caps(dp);
-	dp->link.cap.lanes = 0x2;
 
 	ret = hibmc_dp_get_serdes_rate_cfg(dp);
 	if (ret < 0)

drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c

@@ -32,7 +32,7 @@
 
 DEFINE_DRM_GEM_FOPS(hibmc_fops);
 
-static const char *g_irqs_names_map[HIBMC_MAX_VECTORS] = { "vblank", "hpd" };
+static const char *g_irqs_names_map[HIBMC_MAX_VECTORS] = { "hibmc-vblank", "hibmc-hpd" };
 
 static irqreturn_t hibmc_interrupt(int irq, void *arg)
 {
@@ -115,6 +115,8 @@ static const struct drm_mode_config_funcs hibmc_mode_funcs = {
 static int hibmc_kms_init(struct hibmc_drm_private *priv)
 {
 	struct drm_device *dev = &priv->dev;
+	struct drm_encoder *encoder;
+	u32 clone_mask = 0;
 	int ret;
 
 	ret = drmm_mode_config_init(dev);
@@ -154,6 +156,12 @@ static int hibmc_kms_init(struct hibmc_drm_private *priv)
 		return ret;
 	}
 
+	drm_for_each_encoder(encoder, dev)
+		clone_mask |= drm_encoder_mask(encoder);
+
+	drm_for_each_encoder(encoder, dev)
+		encoder->possible_clones = clone_mask;
+
 	return 0;
 }
 
@@ -277,7 +285,6 @@ static void hibmc_unload(struct drm_device *dev)
 static int hibmc_msi_init(struct drm_device *dev)
 {
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
-	char name[32] = {0};
 	int valid_irq_num;
 	int irq;
 	int ret;
@@ -292,9 +299,6 @@ static int hibmc_msi_init(struct drm_device *dev)
 	valid_irq_num = ret;
 
 	for (int i = 0; i < valid_irq_num; i++) {
-		snprintf(name, ARRAY_SIZE(name) - 1, "%s-%s-%s",
-			 dev->driver->name, pci_name(pdev), g_irqs_names_map[i]);
-
 		irq = pci_irq_vector(pdev, i);
 
 		if (i)
@@ -302,10 +306,10 @@ static int hibmc_msi_init(struct drm_device *dev)
 			ret = devm_request_threaded_irq(&pdev->dev, irq,
 							hibmc_dp_interrupt,
 							hibmc_dp_hpd_isr,
-							IRQF_SHARED, name, dev);
+							IRQF_SHARED, g_irqs_names_map[i], dev);
 		else
 			ret = devm_request_irq(&pdev->dev, irq, hibmc_interrupt,
-					       IRQF_SHARED, name, dev);
+					       IRQF_SHARED, g_irqs_names_map[i], dev);
 		if (ret) {
 			drm_err(dev, "install irq failed: %d\n", ret);
 			return ret;
@@ -323,13 +327,13 @@ static int hibmc_load(struct drm_device *dev)
 
 	ret = hibmc_hw_init(priv);
 	if (ret)
-		goto err;
+		return ret;
 
 	ret = drmm_vram_helper_init(dev, pci_resource_start(pdev, 0),
 				    pci_resource_len(pdev, 0));
 	if (ret) {
 		drm_err(dev, "Error initializing VRAM MM; %d\n", ret);
-		goto err;
+		return ret;
 	}
 
 	ret = hibmc_kms_init(priv);

drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.h

@@ -69,6 +69,7 @@ int hibmc_de_init(struct hibmc_drm_private *priv);
 int hibmc_vdac_init(struct hibmc_drm_private *priv);
 
 int hibmc_ddc_create(struct drm_device *drm_dev, struct hibmc_vdac *connector);
+void hibmc_ddc_del(struct hibmc_vdac *vdac);
 
 int hibmc_dp_init(struct hibmc_drm_private *priv);
 

drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_i2c.c

@@ -95,3 +95,8 @@ int hibmc_ddc_create(struct drm_device *drm_dev, struct hibmc_vdac *vdac)
 
 	return i2c_bit_add_bus(&vdac->adapter);
 }
+
+void hibmc_ddc_del(struct hibmc_vdac *vdac)
+{
+	i2c_del_adapter(&vdac->adapter);
+}

drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_vdac.c

@@ -53,7 +53,7 @@ static void hibmc_connector_destroy(struct drm_connector *connector)
 {
 	struct hibmc_vdac *vdac = to_hibmc_vdac(connector);
 
-	i2c_del_adapter(&vdac->adapter);
+	hibmc_ddc_del(vdac);
 	drm_connector_cleanup(connector);
 }
 
@@ -110,7 +110,7 @@ int hibmc_vdac_init(struct hibmc_drm_private *priv)
 	ret = drmm_encoder_init(dev, encoder, NULL, DRM_MODE_ENCODER_DAC, NULL);
 	if (ret) {
 		drm_err(dev, "failed to init encoder: %d\n", ret);
-		return ret;
+		goto err;
 	}
 
 	drm_encoder_helper_add(encoder, &hibmc_encoder_helper_funcs);
@@ -121,7 +121,7 @@ int hibmc_vdac_init(struct hibmc_drm_private *priv)
 					  &vdac->adapter);
 	if (ret) {
 		drm_err(dev, "failed to init connector: %d\n", ret);
-		return ret;
+		goto err;
 	}
 
 	drm_connector_helper_add(connector, &hibmc_connector_helper_funcs);
@@ -131,4 +131,9 @@ int hibmc_vdac_init(struct hibmc_drm_private *priv)
 	connector->polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
 
 	return 0;
+
+err:
+	hibmc_ddc_del(vdac);
+
+	return ret;
 }

drivers/gpu/drm/nouveau/nouveau_exec.c

@@ -60,14 +60,14 @@
  * virtual address in the GPU's VA space there is no guarantee that the actual
  * mappings are created in the GPU's MMU. If the given memory is swapped out
  * at the time the bind operation is executed the kernel will stash the mapping
- * details into it's internal alloctor and create the actual MMU mappings once
+ * details into it's internal allocator and create the actual MMU mappings once
  * the memory is swapped back in. While this is transparent for userspace, it is
  * guaranteed that all the backing memory is swapped back in and all the memory
  * mappings, as requested by userspace previously, are actually mapped once the
  * DRM_NOUVEAU_EXEC ioctl is called to submit an exec job.
  *
  * A VM_BIND job can be executed either synchronously or asynchronously. If
- * exectued asynchronously, userspace may provide a list of syncobjs this job
+ * executed asynchronously, userspace may provide a list of syncobjs this job
  * will wait for and/or a list of syncobj the kernel will signal once the
  * VM_BIND job finished execution. If executed synchronously the ioctl will
  * block until the bind job is finished. For synchronous jobs the kernel will
@@ -82,7 +82,7 @@
  * Since VM_BIND jobs update the GPU's VA space on job submit, EXEC jobs do have
  * an up to date view of the VA space. However, the actual mappings might still
  * be pending. Hence, EXEC jobs require to have the particular fences - of
- * the corresponding VM_BIND jobs they depent on - attached to them.
+ * the corresponding VM_BIND jobs they depend on - attached to them.
  */
 
 static int

drivers/gpu/drm/nouveau/nvif/vmm.c

@@ -219,7 +219,8 @@ nvif_vmm_ctor(struct nvif_mmu *mmu, const char *name, s32 oclass,
 	case RAW: args->type = NVIF_VMM_V0_TYPE_RAW; break;
 	default:
 		WARN_ON(1);
-		return -EINVAL;
+		ret = -EINVAL;
+		goto done;
 	}
 
 	memcpy(args->data, argv, argc);

drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/rpc.c

@@ -325,7 +325,7 @@ r535_gsp_msgq_recv(struct nvkm_gsp *gsp, u32 gsp_rpc_len, int *retries)
 
 		rpc = r535_gsp_msgq_peek(gsp, sizeof(*rpc), info.retries);
 		if (IS_ERR_OR_NULL(rpc)) {
-			kfree(buf);
+			kvfree(buf);
 			return rpc;
 		}
 
@@ -334,7 +334,7 @@ r535_gsp_msgq_recv(struct nvkm_gsp *gsp, u32 gsp_rpc_len, int *retries)
 
 		rpc = r535_gsp_msgq_recv_one_elem(gsp, &info);
 		if (IS_ERR_OR_NULL(rpc)) {
-			kfree(buf);
+			kvfree(buf);
 			return rpc;
 		}
 

drivers/gpu/drm/nova/file.rs

@@ -39,7 +39,8 @@ impl File {
             _ => return Err(EINVAL),
         };
 
-        getparam.set_value(value);
+        #[allow(clippy::useless_conversion)]
+        getparam.set_value(value.into());
 
         Ok(0)
     }

drivers/gpu/drm/rockchip/Kconfig

@@ -53,6 +53,7 @@ config ROCKCHIP_CDN_DP
 	bool "Rockchip cdn DP"
 	depends on EXTCON=y || (EXTCON=m && DRM_ROCKCHIP=m)
 	select DRM_DISPLAY_HELPER
+	select DRM_BRIDGE_CONNECTOR
 	select DRM_DISPLAY_DP_HELPER
 	help
 	  This selects support for Rockchip SoC specific extensions

drivers/gpu/drm/rockchip/rockchip_drm_vop2.c

@@ -2579,12 +2579,13 @@ static int vop2_win_init(struct vop2 *vop2)
 }
 
 /*
- * The window registers are only updated when config done is written.
+ * The window and video port registers are only updated when config
- * Until that they read back the old value. As we read-modify-write
+ * done is written. Until that they read back the old value. As we
- * these registers mark them as non-volatile. This makes sure we read
+ * read-modify-write these registers mark them as non-volatile. This
- * the new values from the regmap register cache.
+ * makes sure we read the new values from the regmap register cache.
  */
 static const struct regmap_range vop2_nonvolatile_range[] = {
+	regmap_reg_range(RK3568_VP0_CTRL_BASE, RK3588_VP3_CTRL_BASE + 255),
 	regmap_reg_range(0x1000, 0x23ff),
 };
 

drivers/gpu/drm/tests/drm_format_helper_test.c

@@ -1033,13 +1033,14 @@ static void drm_test_fb_xrgb8888_to_xrgb2101010(struct kunit *test)
 		NULL : &result->dst_pitch;
 
 	drm_fb_xrgb8888_to_xrgb2101010(&dst, dst_pitch, &src, &fb, &params->clip, &fmtcnv_state);
-	buf = le32buf_to_cpu(test, buf, dst_size / sizeof(u32));
+	buf = le32buf_to_cpu(test, (__force const __le32 *)buf, dst_size / sizeof(u32));
 	KUNIT_EXPECT_MEMEQ(test, buf, result->expected, dst_size);
 
 	buf = dst.vaddr; /* restore original value of buf */
 	memset(buf, 0, dst_size);
 
 	drm_fb_xrgb8888_to_xrgb2101010(&dst, dst_pitch, &src, &fb, &params->clip, &fmtcnv_state);
+	buf = le32buf_to_cpu(test, (__force const __le32 *)buf, dst_size / sizeof(u32));
 	KUNIT_EXPECT_MEMEQ(test, buf, result->expected, dst_size);
 }
 

include/linux/iosys-map.h

@@ -264,12 +264,7 @@ static inline bool iosys_map_is_set(const struct iosys_map *map)
  */
 static inline void iosys_map_clear(struct iosys_map *map)
 {
-	if (map->is_iomem) {
+	memset(map, 0, sizeof(*map));
-		map->vaddr_iomem = NULL;
-		map->is_iomem = false;
-	} else {
-		map->vaddr = NULL;
-	}
 }
 
 /**

rust/kernel/alloc/allocator.rs

@@ -43,17 +43,6 @@ pub struct Vmalloc;
 /// For more details see [self].
 pub struct KVmalloc;
 
-/// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment.
-fn aligned_size(new_layout: Layout) -> usize {
-    // Customized layouts from `Layout::from_size_align()` can have size < align, so pad first.
-    let layout = new_layout.pad_to_align();
-
-    // Note that `layout.size()` (after padding) is guaranteed to be a multiple of `layout.align()`
-    // which together with the slab guarantees means the `krealloc` will return a properly aligned
-    // object (see comments in `kmalloc()` for more information).
-    layout.size()
-}
-
 /// # Invariants
 ///
 /// One of the following: `krealloc`, `vrealloc`, `kvrealloc`.
@@ -88,7 +77,7 @@ impl ReallocFunc {
         old_layout: Layout,
         flags: Flags,
     ) -> Result<NonNull<[u8]>, AllocError> {
-        let size = aligned_size(layout);
+        let size = layout.size();
         let ptr = match ptr {
             Some(ptr) => {
                 if old_layout.size() == 0 {
@@ -123,6 +112,17 @@ impl ReallocFunc {
     }
 }
 
+impl Kmalloc {
+    /// Returns a [`Layout`] that makes [`Kmalloc`] fulfill the requested size and alignment of
+    /// `layout`.
+    pub fn aligned_layout(layout: Layout) -> Layout {
+        // Note that `layout.size()` (after padding) is guaranteed to be a multiple of
+        // `layout.align()` which together with the slab guarantees means that `Kmalloc` will return
+        // a properly aligned object (see comments in `kmalloc()` for more information).
+        layout.pad_to_align()
+    }
+}
+
 // SAFETY: `realloc` delegates to `ReallocFunc::call`, which guarantees that
 // - memory remains valid until it is explicitly freed,
 // - passing a pointer to a valid memory allocation is OK,
@@ -135,6 +135,8 @@ unsafe impl Allocator for Kmalloc {
         old_layout: Layout,
         flags: Flags,
     ) -> Result<NonNull<[u8]>, AllocError> {
+        let layout = Kmalloc::aligned_layout(layout);
+
         // SAFETY: `ReallocFunc::call` has the same safety requirements as `Allocator::realloc`.
         unsafe { ReallocFunc::KREALLOC.call(ptr, layout, old_layout, flags) }
     }
@@ -176,6 +178,10 @@ unsafe impl Allocator for KVmalloc {
         old_layout: Layout,
         flags: Flags,
     ) -> Result<NonNull<[u8]>, AllocError> {
+        // `KVmalloc` may use the `Kmalloc` backend, hence we have to enforce a `Kmalloc`
+        // compatible layout.
+        let layout = Kmalloc::aligned_layout(layout);
+
         // TODO: Support alignments larger than PAGE_SIZE.
         if layout.align() > bindings::PAGE_SIZE {
             pr_warn!("KVmalloc does not support alignments larger than PAGE_SIZE yet.\n");

rust/kernel/alloc/allocator_test.rs

@@ -22,6 +22,17 @@ pub type Kmalloc = Cmalloc;
 pub type Vmalloc = Kmalloc;
 pub type KVmalloc = Kmalloc;
 
+impl Cmalloc {
+    /// Returns a [`Layout`] that makes [`Kmalloc`] fulfill the requested size and alignment of
+    /// `layout`.
+    pub fn aligned_layout(layout: Layout) -> Layout {
+        // Note that `layout.size()` (after padding) is guaranteed to be a multiple of
+        // `layout.align()` which together with the slab guarantees means that `Kmalloc` will return
+        // a properly aligned object (see comments in `kmalloc()` for more information).
+        layout.pad_to_align()
+    }
+}
+
 extern "C" {
     #[link_name = "aligned_alloc"]
     fn libc_aligned_alloc(align: usize, size: usize) -> *mut crate::ffi::c_void;

rust/kernel/drm/device.rs

@@ -5,6 +5,7 @@
 //! C header: [`include/linux/drm/drm_device.h`](srctree/include/linux/drm/drm_device.h)
 
 use crate::{
+    alloc::allocator::Kmalloc,
     bindings, device, drm,
     drm::driver::AllocImpl,
     error::from_err_ptr,
@@ -12,7 +13,7 @@ use crate::{
     prelude::*,
     types::{ARef, AlwaysRefCounted, Opaque},
 };
-use core::{mem, ops::Deref, ptr, ptr::NonNull};
+use core::{alloc::Layout, mem, ops::Deref, ptr, ptr::NonNull};
 
 #[cfg(CONFIG_DRM_LEGACY)]
 macro_rules! drm_legacy_fields {
@@ -53,10 +54,8 @@ macro_rules! drm_legacy_fields {
 ///
 /// `self.dev` is a valid instance of a `struct device`.
 #[repr(C)]
-#[pin_data]
 pub struct Device<T: drm::Driver> {
     dev: Opaque<bindings::drm_device>,
-    #[pin]
     data: T::Data,
 }
 
@@ -96,6 +95,10 @@ impl<T: drm::Driver> Device<T> {
 
     /// Create a new `drm::Device` for a `drm::Driver`.
     pub fn new(dev: &device::Device, data: impl PinInit<T::Data, Error>) -> Result<ARef<Self>> {
+        // `__drm_dev_alloc` uses `kmalloc()` to allocate memory, hence ensure a `kmalloc()`
+        // compatible `Layout`.
+        let layout = Kmalloc::aligned_layout(Layout::new::<Self>());
+
         // SAFETY:
         // - `VTABLE`, as a `const` is pinned to the read-only section of the compilation,
         // - `dev` is valid by its type invarants,
@@ -103,7 +106,7 @@ impl<T: drm::Driver> Device<T> {
             bindings::__drm_dev_alloc(
                 dev.as_raw(),
                 &Self::VTABLE,
-                mem::size_of::<Self>(),
+                layout.size(),
                 mem::offset_of!(Self, dev),
             )
         }
@@ -117,9 +120,13 @@ impl<T: drm::Driver> Device<T> {
         // - `raw_data` is a valid pointer to uninitialized memory.
         // - `raw_data` will not move until it is dropped.
         unsafe { data.__pinned_init(raw_data) }.inspect_err(|_| {
-            // SAFETY: `__drm_dev_alloc()` was successful, hence `raw_drm` must be valid and the
+            // SAFETY: `raw_drm` is a valid pointer to `Self`, given that `__drm_dev_alloc` was
+            // successful.
+            let drm_dev = unsafe { Self::into_drm_device(raw_drm) };
+
+            // SAFETY: `__drm_dev_alloc()` was successful, hence `drm_dev` must be valid and the
             // refcount must be non-zero.
-            unsafe { bindings::drm_dev_put(ptr::addr_of_mut!((*raw_drm.as_ptr()).dev).cast()) };
+            unsafe { bindings::drm_dev_put(drm_dev) };
         })?;
 
         // SAFETY: The reference count is one, and now we take ownership of that reference as a
@@ -140,6 +147,14 @@ impl<T: drm::Driver> Device<T> {
         unsafe { crate::container_of!(Opaque::cast_from(ptr), Self, dev) }.cast_mut()
     }
 
+    /// # Safety
+    ///
+    /// `ptr` must be a valid pointer to `Self`.
+    unsafe fn into_drm_device(ptr: NonNull<Self>) -> *mut bindings::drm_device {
+        // SAFETY: By the safety requirements of this function, `ptr` is a valid pointer to `Self`.
+        unsafe { &raw mut (*ptr.as_ptr()).dev }.cast()
+    }
+
     /// Not intended to be called externally, except via declare_drm_ioctls!()
     ///
     /// # Safety
@@ -189,8 +204,11 @@ unsafe impl<T: drm::Driver> AlwaysRefCounted for Device<T> {
     }
 
     unsafe fn dec_ref(obj: NonNull<Self>) {
+        // SAFETY: `obj` is a valid pointer to `Self`.
+        let drm_dev = unsafe { Self::into_drm_device(obj) };
+
         // SAFETY: The safety requirements guarantee that the refcount is non-zero.
-        unsafe { bindings::drm_dev_put(obj.cast().as_ptr()) };
+        unsafe { bindings::drm_dev_put(drm_dev) };
     }
 }