Linaro-mm-sig December 2025

linaro-mm-sig@lists.linaro.org

56 participants
42 discussions

[PATCH v6 2/8] rust: helpers: Add bindings/wrappers for dma_resv_lock

by Lyude Paul

From: Asahi Lina <lina(a)asahilina.net> This is just for basic usage in the DRM shmem abstractions for implied locking, not intended as a full DMA Reservation abstraction yet. Signed-off-by: Asahi Lina <lina(a)asahilina.net> Signed-off-by: Daniel Almeida <daniel.almeida(a)collabora.com> Reviewed-by: Alice Ryhl <aliceryhl(a)google.com> Signed-off-by: Lyude Paul <lyude(a)redhat.com> --- rust/bindings/bindings_helper.h | 1 + rust/helpers/dma-resv.c | 13 +++++++++++++ rust/helpers/helpers.c | 1 + 3 files changed, 15 insertions(+) create mode 100644 rust/helpers/dma-resv.c diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h index 2e43c66635a2c..07f79e125c329 100644 --- a/rust/bindings/bindings_helper.h +++ b/rust/bindings/bindings_helper.h @@ -48,6 +48,7 @@ #include <linux/cpumask.h> #include <linux/cred.h> #include <linux/debugfs.h> +#include <linux/dma-resv.h> #include <linux/device/faux.h> #include <linux/dma-direction.h> #include <linux/dma-mapping.h> diff --git a/rust/helpers/dma-resv.c b/rust/helpers/dma-resv.c new file mode 100644 index 0000000000000..05501cb814513 --- /dev/null +++ b/rust/helpers/dma-resv.c @@ -0,0 +1,13 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/dma-resv.h> + +int rust_helper_dma_resv_lock(struct dma_resv *obj, struct ww_acquire_ctx *ctx) +{ + return dma_resv_lock(obj, ctx); +} + +void rust_helper_dma_resv_unlock(struct dma_resv *obj) +{ + dma_resv_unlock(obj); +} diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c index 551da6c9b5064..36d40f911345c 100644 --- a/rust/helpers/helpers.c +++ b/rust/helpers/helpers.c @@ -25,6 +25,7 @@ #include "cred.c" #include "device.c" #include "dma.c" +#include "dma-resv.c" #include "drm.c" #include "err.c" #include "irq.c" -- 2.52.0

4 months, 1 week

[syzbot] [media?] [dri?] WARNING in dma_buf_vmap

by syzbot

Hello, syzbot found the following issue on: HEAD commit: 1d18101a644e Merge tag 'kernel-6.19-rc1.cred' of git://git.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=13fba192580000 kernel config: https://syzkaller.appspot.com/x/.config?x=a1db0fea040c2a9f dashboard link: https://syzkaller.appspot.com/bug?extid=4317d7108e14e5d56308 compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1055e2b4580000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16ddf484580000 Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk… vmlinux: https://storage.googleapis.com/syzbot-assets/98f78b52cccd/vmlinux-1d18101a.… kernel image: https://storage.googleapis.com/syzbot-assets/7a8898061bfb/bzImage-1d18101a.… IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+4317d7108e14e5d56308(a)syzkaller.appspotmail.com Total swap = 124996kB 393083 pages RAM 0 pages HighMem/MovableOnly 184478 pages reserved 0 pages cma reserved ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5488 at drivers/dma-buf/dma-buf.c:1536 dma_buf_vmap+0x306/0x3b0 drivers/dma-buf/dma-buf.c:1536 Modules linked in: CPU: 0 UID: 0 PID: 5488 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:dma_buf_vmap+0x306/0x3b0 drivers/dma-buf/dma-buf.c:1536 Code: 64 05 cc e8 0c 99 d7 fb 90 0f 0b 90 b8 ea ff ff ff eb bc e8 fc 98 d7 fb 90 0f 0b 90 e9 0d fe ff ff e8 ee 98 d7 fb 44 89 f0 90 <0f> 0b 90 49 bd 00 00 00 00 00 fc ff df eb 91 e8 c6 9c 61 05 48 c7 RSP: 0018:ffffc90002bbf3a0 EFLAGS: 00010293 RAX: 00000000fffffff4 RBX: ffff888000e02428 RCX: ffff888000eb4900 RDX: 0000000000000000 RSI: 00000000fffffff4 RDI: 0000000000000000 RBP: ffffc90002bbf450 R08: ffffc90002bbf227 R09: 1ffff92000577e44 R10: dffffc0000000000 R11: fffff52000577e45 R12: ffffffff85ea4500 R13: ffff888000e02430 R14: 00000000fffffff4 R15: 1ffff110001c0485 FS: 0000555591ecc500(0000) GS:ffff88808d722000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055859af10a08 CR3: 00000000589bb000 CR4: 0000000000352ef0 Call Trace: <TASK> drm_gem_shmem_vmap_locked+0x14c/0x790 drivers/gpu/drm/drm_gem_shmem_helper.c:354 drm_gem_vmap_locked drivers/gpu/drm/drm_gem.c:1279 [inline] drm_gem_vmap+0x10a/0x1d0 drivers/gpu/drm/drm_gem.c:1321 drm_gem_fb_vmap+0xaa/0x8d0 drivers/gpu/drm/drm_gem_framebuffer_helper.c:368 drm_atomic_helper_prepare_planes+0x2d6/0xb60 drivers/gpu/drm/drm_atomic_helper.c:2760 drm_atomic_helper_commit+0x19a/0xb10 drivers/gpu/drm/drm_atomic_helper.c:2189 drm_atomic_commit+0x262/0x2c0 drivers/gpu/drm/drm_atomic.c:1577 drm_atomic_helper_update_plane+0x248/0x3b0 drivers/gpu/drm/drm_atomic_helper.c:3348 drm_mode_cursor_universal drivers/gpu/drm/drm_plane.c:1256 [inline] drm_mode_cursor_common+0xb7e/0x12d0 drivers/gpu/drm/drm_plane.c:1315 drm_mode_cursor_ioctl+0xbf/0x110 drivers/gpu/drm/drm_plane.c:1365 drm_ioctl_kernel+0x2cf/0x390 drivers/gpu/drm/drm_ioctl.c:797 drm_ioctl+0x67f/0xb10 drivers/gpu/drm/drm_ioctl.c:894 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcd9898f7c9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe37777948 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcd98be5fa0 RCX: 00007fcd9898f7c9 RDX: 0000200000000280 RSI: 00000000c01c64a3 RDI: 0000000000000003 RBP: 00007ffe377779a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007fcd98be5fa0 R14: 00007fcd98be5fa0 R15: 0000000000000003 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller(a)googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup

4 months, 1 week

[PATCH 1/2] dma-buf: improve sg_table debugging hack v3

by Christian König

This debugging hack is important to enforce the rule that importers should *never* touch the underlying struct page of the exporter. Instead of just mangling the page link create a copy of the sg_table but only copy over the DMA addresses and not the pages. This will cause a NULL pointer de-reference if the importer tries to touch the struct page. Still quite a hack but this at least allows the exporter to properly keeps it's sg_table intact while allowing the DMA-buf maintainer to find and fix misbehaving importers and finally switch over to using a different data structure in the future. v2: improve the hack further by using a wrapper structure and explaining the background a bit more in the commit message. v3: fix some whitespace issues, use sg_assign_page(). Signed-off-by: Christian König <christian.koenig(a)amd.com> Reviewed-by: Michael J. Ruhl <michael.j.ruhl(a)intel.com> (v1) --- drivers/dma-buf/dma-buf.c | 74 +++++++++++++++++++++++++++++++-------- 1 file changed, 60 insertions(+), 14 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 2305bb2cc1f1..944f4103b5cc 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -35,6 +35,12 @@ #include "dma-buf-sysfs-stats.h" +/* Wrapper to hide the sg_table page link from the importer */ +struct dma_buf_sg_table_wrapper { + struct sg_table *original; + struct sg_table wrapper; +}; + static inline int is_dma_buf_file(struct file *); static DEFINE_MUTEX(dmabuf_list_mutex); @@ -828,21 +834,59 @@ void dma_buf_put(struct dma_buf *dmabuf) } EXPORT_SYMBOL_NS_GPL(dma_buf_put, "DMA_BUF"); -static void mangle_sg_table(struct sg_table *sg_table) +static int dma_buf_mangle_sg_table(struct sg_table **sg_table) { -#ifdef CONFIG_DMABUF_DEBUG - int i; - struct scatterlist *sg; - - /* To catch abuse of the underlying struct page by importers mix - * up the bits, but take care to preserve the low SG_ bits to - * not corrupt the sgt. The mixing is undone on unmap - * before passing the sgt back to the exporter. + struct scatterlist *to_sg, *from_sg; + struct sg_table *from = *sg_table; + struct dma_buf_sg_table_wrapper *to; + int i, ret; + + if (!IS_ENABLED(CONFIG_DMABUF_DEBUG)) + return 0; + + /* + * To catch abuse of the underlying struct page by importers copy the + * sg_table without copying the page_link and give only the copy back to + * the importer. */ - for_each_sgtable_sg(sg_table, sg, i) - sg->page_link ^= ~0xffUL; -#endif + to = kzalloc(sizeof(*to), GFP_KERNEL); + if (!to) + return -ENOMEM; + + ret = sg_alloc_table(&to->wrapper, from->nents, GFP_KERNEL); + if (ret) + goto free_to; + + to_sg = to->wrapper.sgl; + for_each_sgtable_dma_sg(from, from_sg, i) { + to_sg->offset = 0; + to_sg->length = 0; + sg_assign_page(to_sg, NULL); + sg_dma_address(to_sg) = sg_dma_address(from_sg); + sg_dma_len(to_sg) = sg_dma_len(from_sg); + to_sg = sg_next(to_sg); + } + to->original = from; + *sg_table = &to->wrapper; + return 0; + +free_to: + kfree(to); + return ret; +} + +static void dma_buf_demangle_sg_table(struct sg_table **sg_table) +{ + struct dma_buf_sg_table_wrapper *copy; + + if (!IS_ENABLED(CONFIG_DMABUF_DEBUG)) + return; + + copy = container_of(*sg_table, typeof(*copy), wrapper); + *sg_table = copy->original; + sg_free_table(&copy->wrapper); + kfree(copy); } static inline bool @@ -1139,7 +1183,9 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, if (ret < 0) goto error_unmap; } - mangle_sg_table(sg_table); + ret = dma_buf_mangle_sg_table(&sg_table); + if (ret) + goto error_unmap; if (IS_ENABLED(CONFIG_DMA_API_DEBUG)) { struct scatterlist *sg; @@ -1220,7 +1266,7 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, dma_resv_assert_held(attach->dmabuf->resv); - mangle_sg_table(sg_table); + dma_buf_demangle_sg_table(&sg_table); attach->dmabuf->ops->unmap_dma_buf(attach, sg_table, direction); if (dma_buf_pin_on_map(attach)) -- 2.43.0

4 months, 1 week

Reasonable maximum signaling timeout for dma_fences

by Christian König

Hi everybody, we have documented here https://www.kernel.org/doc/html/latest/driver-api/dma-buf.html#dma-fence-cr… that dma_fence objects must signal in a reasonable amount of time, but at the same time note that drivers might have a different idea of what reasonable means. Recently I realized that this is actually not a good idea. Background is that the wall clock timeout means that for example the OOM killer might actually wait for this timeout to be able to terminate a process and reclaim the memory used. And this is just an example of how general kernel features might depend on that. Some drivers and fence implementations used 10 seconds and that raised complains by end users. So at least amdgpu recently switched to 2 second which triggered an internal discussion about it. This patch set here now adds a define to the dma_fence header which gives 2 seconds as reasonable amount of time. SW-sync is modified to always taint the kernel (since it doesn't has a timeout), VGEM is switched over to the new define and the scheduler gets a warning and taints the kernel if a driver uses a timeout longer than that. I have not much intention of actually committing the patches (maybe except the SW-sync one), but question is if 2 seconds are reasonable? Regards, Christian.

4 months, 2 weeks

[PATCH 1/2] dma-buf: improve sg_table debugging hack v2

by Christian König

This debugging hack is important to enforce the rule that importers should *never* touch the underlying struct page of the exporter. Instead of just mangling the page link create a copy of the sg_table but only copy over the DMA addresses and not the pages. This will cause a NULL pointer de-reference if the importer tries to touch the struct page. Still quite a hack but this at least allows the exporter to properly keeps it's sg_table intact while allowing the DMA-buf maintainer to find and fix misbehaving importers and finally switch over to using a different data structure in the future. v2: improve the hack further by using a wrapper structure and explaining the background a bit more in the commit message. Signed-off-by: Christian König <christian.koenig(a)amd.com> Reviewed-by: Michael J. Ruhl <michael.j.ruhl(a)intel.com> (v1) --- drivers/dma-buf/dma-buf.c | 72 +++++++++++++++++++++++++++++++-------- 1 file changed, 58 insertions(+), 14 deletions(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 2305bb2cc1f1..8c4afd360b72 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -35,6 +35,12 @@ #include "dma-buf-sysfs-stats.h" +/* Wrapper to hide the sg_table page link from the importer */ +struct dma_buf_sg_table_wrapper { + struct sg_table *original; + struct sg_table wrapper; +}; + static inline int is_dma_buf_file(struct file *); static DEFINE_MUTEX(dmabuf_list_mutex); @@ -828,21 +834,57 @@ void dma_buf_put(struct dma_buf *dmabuf) } EXPORT_SYMBOL_NS_GPL(dma_buf_put, "DMA_BUF"); -static void mangle_sg_table(struct sg_table *sg_table) +static int dma_buf_mangle_sg_table(struct sg_table **sg_table) { -#ifdef CONFIG_DMABUF_DEBUG - int i; - struct scatterlist *sg; - - /* To catch abuse of the underlying struct page by importers mix - * up the bits, but take care to preserve the low SG_ bits to - * not corrupt the sgt. The mixing is undone on unmap - * before passing the sgt back to the exporter. + struct scatterlist *to_sg, *from_sg; + struct sg_table *from = *sg_table; + struct dma_buf_sg_table_wrapper *to; + int i, ret; + + if (!IS_ENABLED(CONFIG_DMABUF_DEBUG)) + return 0; + + /* + * To catch abuse of the underlying struct page by importers copy the + * sg_table without copying the page_link and give only the copy back to + * the importer. */ - for_each_sgtable_sg(sg_table, sg, i) - sg->page_link ^= ~0xffUL; -#endif + to = kzalloc(sizeof(*to), GFP_KERNEL); + if (!to) + return -ENOMEM; + + ret = sg_alloc_table(&to->wrapper, from->nents, GFP_KERNEL); + if (ret) + goto free_to; + + to_sg = to->wrapper.sgl; + for_each_sgtable_dma_sg(from, from_sg, i) { + sg_set_page(to_sg, NULL, 0, 0); + sg_dma_address(to_sg) = sg_dma_address(from_sg); + sg_dma_len(to_sg) = sg_dma_len(from_sg); + to_sg = sg_next(to_sg); + } + to->original = from; + *sg_table = &to->wrapper; + return 0; + +free_to: + kfree(to); + return ret; +} + +static void dma_buf_demangle_sg_table(struct sg_table **sg_table) +{ + struct dma_buf_sg_table_wrapper *copy; + + if (!IS_ENABLED(CONFIG_DMABUF_DEBUG)) + return; + + copy = container_of(*sg_table, typeof(*copy), wrapper); + *sg_table = copy->original; + sg_free_table(&copy->wrapper); + kfree(copy); } static inline bool @@ -1139,7 +1181,9 @@ struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach, if (ret < 0) goto error_unmap; } - mangle_sg_table(sg_table); + ret = dma_buf_mangle_sg_table(&sg_table); + if (ret) + goto error_unmap; if (IS_ENABLED(CONFIG_DMA_API_DEBUG)) { struct scatterlist *sg; @@ -1220,7 +1264,7 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, dma_resv_assert_held(attach->dmabuf->resv); - mangle_sg_table(sg_table); + dma_buf_demangle_sg_table(&sg_table); attach->dmabuf->ops->unmap_dma_buf(attach, sg_table, direction); if (dma_buf_pin_on_map(attach)) -- 2.43.0

4 months, 2 weeks

[RFC v2 06/11] nvme-pci: add support for dmabuf reggistration

by asml.silence＠gmail.com

The content of this message was lost. It was probably cross-posted to multiple lists and previously handled on another list.

4 months, 2 weeks

[RFC v2 07/11] nvme-pci: implement dma_token backed requests

by asml.silence＠gmail.com

The content of this message was lost. It was probably cross-posted to multiple lists and previously handled on another list.

4 months, 2 weeks

[PATCH v6 3/8] rust: drm: gem: Add raw_dma_resv() function

by Lyude Paul

For retrieving a pointer to the struct dma_resv for a given GEM object. We also introduce it in a new trait, BaseObjectPrivate, which we automatically implement for all gem objects and don't expose to users outside of the crate. Signed-off-by: Lyude Paul <lyude(a)redhat.com> --- rust/kernel/drm/gem/mod.rs | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/rust/kernel/drm/gem/mod.rs b/rust/kernel/drm/gem/mod.rs index 5c215e83c1b09..ec3c1b1775196 100644 --- a/rust/kernel/drm/gem/mod.rs +++ b/rust/kernel/drm/gem/mod.rs @@ -199,6 +199,18 @@ fn create_mmap_offset(&self) -> Result<u64> { impl<T: IntoGEMObject> BaseObject for T {} +/// Crate-private base operations shared by all GEM object classes. +#[expect(unused)] +pub(crate) trait BaseObjectPrivate: IntoGEMObject { + /// Return a pointer to this object's dma_resv. + fn raw_dma_resv(&self) -> *mut bindings::dma_resv { + // SAFETY: `as_gem_obj()` always returns a valid pointer to the base DRM gem object + unsafe { (*self.as_raw()).resv } + } +} + +impl<T: IntoGEMObject> BaseObjectPrivate for T {} + /// A base GEM object. /// /// # Invariants -- 2.52.0

4 months, 2 weeks

[PATCH RFC] mm/vmap: map contiguous pages in batches whenever possible

by Barry Song

From: Barry Song <v-songbaohua(a)oppo.com> In many cases, the pages passed to vmap() may include high-order pages—for example, the systemheap often allocates pages in descending order: order 8, then 4, then 0. Currently, vmap() iterates over every page individually—even the pages inside a high-order block are handled one by one. This patch detects high-order pages and maps them as a single contiguous block whenever possible. Another possibility is to implement a new API, vmap_sg(). However, that change seems to be quite large in scope. When vmapping a 128MB dma-buf using the systemheap, this RFC appears to make system_heap_do_vmap() 16× faster: W/ patch: [ 51.363682] system_heap_do_vmap took 2474000 ns [ 53.307044] system_heap_do_vmap took 2469008 ns [ 55.061985] system_heap_do_vmap took 2519008 ns [ 56.653810] system_heap_do_vmap took 2674000 ns W/o patch: [ 8.260880] system_heap_do_vmap took 39490000 ns [ 32.513292] system_heap_do_vmap took 38784000 ns [ 82.673374] system_heap_do_vmap took 40711008 ns [ 84.579062] system_heap_do_vmap took 40236000 ns Cc: Uladzislau Rezki <urezki(a)gmail.com> Cc: Sumit Semwal <sumit.semwal(a)linaro.org> Cc: John Stultz <jstultz(a)google.com> Cc: Maxime Ripard <mripard(a)kernel.org> Signed-off-by: Barry Song <v-songbaohua(a)oppo.com> --- mm/vmalloc.c | 49 +++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 43 insertions(+), 6 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 0832f944544c..af2e3e8c052a 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -642,6 +642,34 @@ static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end, return err; } +static inline int get_vmap_batch_order(struct page **pages, + unsigned int stride, + int max_steps, + unsigned int idx) +{ + /* + * Currently, batching is only supported in vmap_pages_range + * when page_shift == PAGE_SHIFT. + */ + if (stride != 1) + return 0; + + struct page *base = pages[idx]; + if (!PageHead(base)) + return 0; + + int order = compound_order(base); + int nr_pages = 1 << order; + + if (max_steps < nr_pages) + return 0; + + for (int i = 0; i < nr_pages; i++) + if (pages[idx + i] != base + i) + return 0; + return order; +} + /* * vmap_pages_range_noflush is similar to vmap_pages_range, but does not * flush caches. @@ -655,23 +683,32 @@ int __vmap_pages_range_noflush(unsigned long addr, unsigned long end, pgprot_t prot, struct page **pages, unsigned int page_shift) { unsigned int i, nr = (end - addr) >> PAGE_SHIFT; + unsigned int stride; WARN_ON(page_shift < PAGE_SHIFT); + /* + * Some users may allocate pages from high-order down to order 0. + * We roughly check if the first page is a compound page. If so, + * there is a chance to batch multiple pages together. + */ if (!IS_ENABLED(CONFIG_HAVE_ARCH_HUGE_VMALLOC) || - page_shift == PAGE_SHIFT) + (page_shift == PAGE_SHIFT && !PageCompound(pages[0]))) return vmap_small_pages_range_noflush(addr, end, prot, pages); - for (i = 0; i < nr; i += 1U << (page_shift - PAGE_SHIFT)) { - int err; + stride = 1U << (page_shift - PAGE_SHIFT); + for (i = 0; i < nr; ) { + int err, order; - err = vmap_range_noflush(addr, addr + (1UL << page_shift), + order = get_vmap_batch_order(pages, stride, nr - i, i); + err = vmap_range_noflush(addr, addr + (1UL << (page_shift + order)), page_to_phys(pages[i]), prot, - page_shift); + page_shift + order); if (err) return err; - addr += 1UL << page_shift; + addr += 1UL << (page_shift + order); + i += 1U << (order + page_shift - PAGE_SHIFT); } return 0; -- 2.39.3 (Apple Git-146)

4 months, 2 weeks

[PATCH v4 00/13] drm/amdgpu: preparation patchs for the use all SDMA instances series

by Pierre-Eric Pelloux-Prayer

This series is a subset of the "use all SDMA instances" series. It starts at the first modified patch and ends at the last patch before the drm/ttm patch that got merged through drm-misc-next. v3 of the full series: https://lists.freedesktop.org/archives/dri-devel/2025-November/537830.html Pierre-Eric Pelloux-Prayer (13): drm/amdgpu: introduce amdgpu_ttm_buffer_entity drm/amdgpu: add amdgpu_ttm_job_submit helper drm/amdgpu: fix error handling in amdgpu_copy_buffer drm/amdgpu: pass the entity to use to amdgpu_ttm_map_buffer drm/amdgpu: pass the entity to use to ttm public functions drm/amdgpu: statically assign gart windows to ttm entities drm/amdgpu: remove AMDGPU_GTT_NUM_TRANSFER_WINDOWS drm/amdgpu: add missing lock in amdgpu_benchmark_do_move drm/amdgpu: check entity lock is held in amdgpu_ttm_job_submit drm/amdgpu: double AMDGPU_GTT_MAX_TRANSFER_SIZE drm/amdgpu: use larger gart window when possible drm/amdgpu: introduce amdgpu_sdma_set_vm_pte_scheds drm/amdgpu: move sched status check inside amdgpu_ttm_set_buffer_funcs_status drivers/gpu/drm/amd/amdgpu/amdgpu.h | 2 + drivers/gpu/drm/amd/amdgpu/amdgpu_benchmark.c | 5 +- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 13 +- drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c | 8 +- drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c | 8 +- drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 4 +- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 295 ++++++++++++------ drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h | 54 +++- drivers/gpu/drm/amd/amdgpu/amdgpu_vce.c | 6 +- drivers/gpu/drm/amd/amdgpu/amdgpu_vce.h | 3 +- drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 17 + drivers/gpu/drm/amd/amdgpu/cik_sdma.c | 31 +- drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c | 31 +- drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c | 31 +- drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c | 35 +-- drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c | 35 +-- drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c | 31 +- drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c | 31 +- drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c | 29 +- drivers/gpu/drm/amd/amdgpu/sdma_v7_0.c | 29 +- drivers/gpu/drm/amd/amdgpu/si_dma.c | 31 +- drivers/gpu/drm/amd/amdgpu/vce_v1_0.c | 12 +- drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 25 +- 23 files changed, 381 insertions(+), 385 deletions(-) -- 2.43.0

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Linaro-mm-sig December 2025