Linaro-mm-sig August 2025

linaro-mm-sig@lists.linaro.org

22 participants
31 discussions

Re: [RFC PATCH 10/30] vfio/pci: Export vfio dma-buf specific info for importers

by Jason Gunthorpe

On Thu, May 29, 2025 at 01:34:53PM +0800, Xu Yilun wrote: > Export vfio dma-buf specific info by attaching vfio_dma_buf_data in > struct dma_buf::priv. Provide a helper vfio_dma_buf_get_data() for > importers to fetch these data. Exporters identify VFIO dma-buf by > successfully getting these data. > > VFIO dma-buf supports disabling host access to these exported MMIO > regions when the device is converted to private. Exporters like KVM > need to identify this type of dma-buf to decide if it is good to use. > KVM only allows host unaccessible MMIO regions been mapped in private > roots. > > Export struct kvm * handler attached to the vfio device. This > allows KVM to do another sanity check. MMIO should only be assigned to > a CoCo VM if its owner device is already assigned to the same VM. This doesn't seem right, it should be encapsulated into the standard DMABUF API in some way. Jason

3 days, 1 hour

Re: [PATCH] drm: docs: Remove item from TODO list

by Maxime Ripard

Hi, On Mon, Oct 23, 2023 at 10:25:50AM -0700, Doug Anderson wrote: > On Mon, Oct 23, 2023 at 9:31 AM Yuran Pereira <yuran.pereira(a)hotmail.com> wrote: > > > > Since "Clean up checks for already prepared/enabled in panels" has > > already been done and merged [1], I think there is no longer a need > > for this item to be in the gpu TODO. > > > > [1] https://patchwork.freedesktop.org/patch/551421/ > > > > Signed-off-by: Yuran Pereira <yuran.pereira(a)hotmail.com> > > --- > > Documentation/gpu/todo.rst | 25 ------------------------- > > 1 file changed, 25 deletions(-) > > It's not actually all done. It's in a bit of a limbo state right now, > unfortunately. I landed all of the "simple" cases where panels were > needlessly tracking prepare/enable, but the less simple cases are > still outstanding. > > Specifically the issue is that many panels have code to properly power > cycle themselves off at shutdown time and in order to do that they > need to keep track of the prepare/enable state. After a big, long > discussion [1] it was decided that we could get rid of all the panel > code handling shutdown if only all relevant DRM KMS drivers would > properly call drm_atomic_helper_shutdown(). > > I made an attempt to get DRM KMS drivers to call > drm_atomic_helper_shutdown() [2] [3] [4]. I was able to land the > patches that went through drm-misc, but currently many of the > non-drm-misc ones are blocked waiting for attention. > > ...so things that could be done to help out: > > a) Could review patches that haven't landed in [4]. Maybe adding a > Reviewed-by tag would help wake up maintainers? > > b) Could see if you can identify panels that are exclusively used w/ > DRM drivers that have already been converted and then we could post > patches for just those panels. I have no idea how easy this task would > be. Is it enough to look at upstream dts files by "compatible" string? I think it is, yes. Maxime

2 weeks

[PATCH v4] Documentation: dma-buf: heaps: Add naming guidelines

by Maxime Ripard

We've discussed a number of times of how some heap names are bad, but not really what makes a good heap name. Let's document what we expect the heap names to look like. Reviewed-by: Andrew Davis <afd(a)ti.com> Reviewed-by: Bagas Sanjaya <bagasdotme(a)gmail.com> Signed-off-by: Maxime Ripard <mripard(a)kernel.org> --- Changes in v4: - Dropped *all* the cacheable mentions - Link to v3: https://lore.kernel.org/r/20250717-dma-buf-heap-names-doc-v3-1-d2dbb4b95ef6… Changes in v3: - Grammar, spelling fixes - Remove the cacheable / uncacheable name suggestion - Link to v2: https://lore.kernel.org/r/20250616-dma-buf-heap-names-doc-v2-1-8ae43174cdbf… Changes in v2: - Added justifications for each requirement / suggestions - Added a mention and example of buffer attributes - Link to v1: https://lore.kernel.org/r/20250520-dma-buf-heap-names-doc-v1-1-ab31f74809ee… --- Documentation/userspace-api/dma-buf-heaps.rst | 35 +++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/Documentation/userspace-api/dma-buf-heaps.rst b/Documentation/userspace-api/dma-buf-heaps.rst index 535f49047ce6450796bf4380c989e109355efc05..1ced2720f929432661182f1a3a88aa1ff80bd6af 100644 --- a/Documentation/userspace-api/dma-buf-heaps.rst +++ b/Documentation/userspace-api/dma-buf-heaps.rst @@ -21,5 +21,40 @@ following heaps: usually created either through the kernel commandline through the `cma` parameter, a memory region Device-Tree node with the `linux,cma-default` property set, or through the `CMA_SIZE_MBYTES` or `CMA_SIZE_PERCENTAGE` Kconfig options. Depending on the platform, it might be called ``reserved``, ``linux,cma``, or ``default-pool``. + +Naming Convention +================= + +``dma-buf`` heaps name should meet a number of constraints: + +- The name must be stable, and must not change from one version to the other. + Userspace identifies heaps by their name, so if the names ever change, we + would be likely to introduce regressions. + +- The name must describe the memory region the heap will allocate from, and + must uniquely identify it in a given platform. Since userspace applications + use the heap name as the discriminant, it must be able to tell which heap it + wants to use reliably if there's multiple heaps. + +- The name must not mention implementation details, such as the allocator. The + heap driver will change over time, and implementation details when it was + introduced might not be relevant in the future. + +- The name should describe properties of the buffers that would be allocated. + Doing so will make heap identification easier for userspace. Such properties + are: + + - ``contiguous`` for physically contiguous buffers; + + - ``protected`` for encrypted buffers not accessible the OS; + +- The name may describe intended usage. Doing so will make heap identification + easier for userspace applications and users. + +For example, assuming a platform with a reserved memory region located +at the RAM address 0x42000000, intended to allocate video framebuffers, +physically contiguous, and backed by the CMA kernel allocator, good +names would be ``memory@42000000-contiguous`` or ``video@42000000``, but +``cma-video`` wouldn't. --- base-commit: 038d61fd642278bab63ee8ef722c50d10ab01e8f change-id: 20250520-dma-buf-heap-names-doc-31261aa0cfe6 Best regards, -- Maxime Ripard <mripard(a)kernel.org>

9 months, 3 weeks

[PATCH v7 0/5] dma-buf: heaps: Create a CMA heap for each CMA reserved region

by Maxime Ripard

Hi, Here's another attempt at supporting user-space allocations from a specific carved-out reserved memory region. The initial problem we were discussing was that I'm currently working on a platform which has a memory layout with ECC enabled. However, enabling the ECC has a number of drawbacks on that platform: lower performance, increased memory usage, etc. So for things like framebuffers, the trade-off isn't great and thus there's a memory region with ECC disabled to allocate from for such use cases. After a suggestion from John, I chose to first start using heap allocations flags to allow for userspace to ask for a particular ECC setup. This is then backed by a new heap type that runs from reserved memory chunks flagged as such, and the existing DT properties to specify the ECC properties. After further discussion, it was considered that flags were not the right solution, and relying on the names of the heaps would be enough to let userspace know the kind of buffer it deals with. Thus, even though the uAPI part of it had been dropped in this second version, we still needed a driver to create heaps out of carved-out memory regions. In addition to the original usecase, a similar driver can be found in BSPs from most vendors, so I believe it would be a useful addition to the kernel. Some extra discussion with Rob Herring [1] came to the conclusion that some specific compatible for this is not great either, and as such an new driver probably isn't called for either. Some other discussions we had with John [2] also dropped some hints that multiple CMA heaps might be a good idea, and some vendors seem to do that too. So here's another attempt that doesn't affect the device tree at all and will just create a heap for every CMA reserved memory region. It also falls nicely into the current plan we have to support cgroups in DRM/KMS and v4l2, which is an additional benefit. Let me know what you think, Maxime 1: https://lore.kernel.org/all/20250707-cobalt-dingo-of-serenity-dbf92c@houat/ 2: https://lore.kernel.org/all/CANDhNCroe6ZBtN_o=c71kzFFaWK-fF5rCdnr9P5h1sgPOW… Let me know what you think, Maxime Signed-off-by: Maxime Ripard <mripard(a)kernel.org> --- Changes in v7: - Invert the logic and register CMA heap from the reserved memory / dma contiguous code, instead of iterating over them from the CMA heap. - Link to v6: https://lore.kernel.org/r/20250709-dma-buf-ecc-heap-v6-0-dac9bf80f35d@kerne… Changes in v6: - Drop the new driver and allocate a CMA heap for each region now - Dropped the binding - Rebased on 6.16-rc5 - Link to v5: https://lore.kernel.org/r/20250617-dma-buf-ecc-heap-v5-0-0abdc5863a4f@kerne… Changes in v5: - Rebased on 6.16-rc2 - Switch from property to dedicated binding - Link to v4: https://lore.kernel.org/r/20250520-dma-buf-ecc-heap-v4-1-bd2e1f1bb42c@kerne… Changes in v4: - Rebased on 6.15-rc7 - Map buffers only when map is actually called, not at allocation time - Deal with restricted-dma-pool and shared-dma-pool - Reword Kconfig options - Properly report dma_map_sgtable failures - Link to v3: https://lore.kernel.org/r/20250407-dma-buf-ecc-heap-v3-0-97cdd36a5f29@kerne… Changes in v3: - Reworked global variable patch - Link to v2: https://lore.kernel.org/r/20250401-dma-buf-ecc-heap-v2-0-043fd006a1af@kerne… Changes in v2: - Add vmap/vunmap operations - Drop ECC flags uapi - Rebase on top of 6.14 - Link to v1: https://lore.kernel.org/r/20240515-dma-buf-ecc-heap-v1-0-54cbbd049511@kerne… --- Maxime Ripard (5): doc: dma-buf: List the heaps by name dma-buf: heaps: cma: Register list of CMA regions at boot dma: contiguous: Register reusable CMA regions at boot dma: contiguous: Reserve default CMA heap dma-buf: heaps: cma: Create CMA heap for each CMA reserved region Documentation/userspace-api/dma-buf-heaps.rst | 24 ++++++++------ MAINTAINERS | 1 + drivers/dma-buf/heaps/Kconfig | 10 ------ drivers/dma-buf/heaps/cma_heap.c | 47 +++++++++++++++++---------- include/linux/dma-buf/heaps/cma.h | 16 +++++++++ kernel/dma/contiguous.c | 11 +++++++ 6 files changed, 72 insertions(+), 37 deletions(-) --- base-commit: 47633099a672fc7bfe604ef454e4f116e2c954b1 change-id: 20240515-dma-buf-ecc-heap-28a311d2c94e prerequisite-message-id: <20250610131231.1724627-1-jkangas(a)redhat.com> prerequisite-patch-id: bc44be5968feb187f2bc1b8074af7209462b18e7 prerequisite-patch-id: f02a91b723e5ec01fbfedf3c3905218b43d432da prerequisite-patch-id: e944d0a3e22f2cdf4d3b3906e5603af934696deb Best regards, -- Maxime Ripard <mripard(a)kernel.org>

10 months, 1 week

Re: [PATCH v11 2/9] dma-buf: dma-heap: export declared functions

by T.J. Mercier

On Wed, Aug 13, 2025 at 11:13 PM Sumit Garg <sumit.garg(a)kernel.org> wrote: > > On Wed, Aug 13, 2025 at 08:02:51AM +0200, Jens Wiklander wrote: > > Export the dma-buf heap functions to allow them to be used by the OP-TEE > > driver. The OP-TEE driver wants to register and manage specific secure > > DMA heaps with it. > > > > Signed-off-by: Jens Wiklander <jens.wiklander(a)linaro.org> > > Reviewed-by: Sumit Garg <sumit.garg(a)oss.qualcomm.com> > > --- > > drivers/dma-buf/dma-heap.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > Can we get an ack from DMAbuf maintainers here? With that we should be > able to queue this patch-set for linux-next targetting the 6.18 merge > window. > > -Sumit Reviewed-by: T.J. Mercier <tjmercier(a)google.com> Sorry I haven't been able to participate much upstream lately. > > > diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c > > index 3cbe87d4a464..cdddf0e24dce 100644 > > --- a/drivers/dma-buf/dma-heap.c > > +++ b/drivers/dma-buf/dma-heap.c > > @@ -202,6 +202,7 @@ void *dma_heap_get_drvdata(struct dma_heap *heap) > > { > > return heap->priv; > > } > > +EXPORT_SYMBOL(dma_heap_get_drvdata); > > > > /** > > * dma_heap_get_name - get heap name > > @@ -214,6 +215,7 @@ const char *dma_heap_get_name(struct dma_heap *heap) > > { > > return heap->name; > > } > > +EXPORT_SYMBOL(dma_heap_get_name); > > > > /** > > * dma_heap_add - adds a heap to dmabuf heaps > > @@ -303,6 +305,7 @@ struct dma_heap *dma_heap_add(const struct dma_heap_export_info *exp_info) > > kfree(heap); > > return err_ret; > > } > > +EXPORT_SYMBOL(dma_heap_add); > > > > static char *dma_heap_devnode(const struct device *dev, umode_t *mode) > > { > > -- > > 2.43.0 > >

10 months, 1 week

[PATCH v1 00/10] vfio/pci: Allow MMIO regions to be exported through dma-buf

by Leon Romanovsky

Changelog: v1: * Changed commit messages. * Reused DMA_ATTR_MMIO attribute. * Returned support for multiple DMA ranges per-dMABUF. v0: https://lore.kernel.org/all/cover.1753274085.git.leonro@nvidia.com --------------------------------------------------------------------------- Based on "[PATCH v1 00/16] dma-mapping: migrate to physical address-based API" https://lore.kernel.org/all/cover.1754292567.git.leon@kernel.org series. --------------------------------------------------------------------------- This series extends the VFIO PCI subsystem to support exporting MMIO regions from PCI device BARs as dma-buf objects, enabling safe sharing of non-struct page memory with controlled lifetime management. This allows RDMA and other subsystems to import dma-buf FDs and build them into memory regions for PCI P2P operations. The series supports a use case for SPDK where a NVMe device will be owned by SPDK through VFIO but interacting with a RDMA device. The RDMA device may directly access the NVMe CMB or directly manipulate the NVMe device's doorbell using PCI P2P. However, as a general mechanism, it can support many other scenarios with VFIO. This dmabuf approach can be usable by iommufd as well for generic and safe P2P mappings. In addition to the SPDK use-case mentioned above, the capability added in this patch series can also be useful when a buffer (located in device memory such as VRAM) needs to be shared between any two dGPU devices or instances (assuming one of them is bound to VFIO PCI) as long as they are P2P DMA compatible. The implementation provides a revocable attachment mechanism using dma-buf move operations. MMIO regions are normally pinned as BARs don't change physical addresses, but access is revoked when the VFIO device is closed or a PCI reset is issued. This ensures kernel self-defense against potentially hostile userspace. The series includes significant refactoring of the PCI P2PDMA subsystem to separate core P2P functionality from memory allocation features, making it more modular and suitable for VFIO use cases that don't need struct page support. ----------------------------------------------------------------------- The series is based originally on https://lore.kernel.org/all/20250307052248.405803-1-vivek.kasireddy@intel.c… but heavily rewritten to be based on DMA physical API. ----------------------------------------------------------------------- The WIP branch can be found here: https://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma.git/log/?h=… Thanks Leon Romanovsky (8): PCI/P2PDMA: Remove redundant bus_offset from map state PCI/P2PDMA: Separate the mmap() support from the core logic PCI/P2PDMA: Simplify bus address mapping API PCI/P2PDMA: Refactor to separate core P2P functionality from memory allocation PCI/P2PDMA: Export pci_p2pdma_map_type() function types: move phys_vec definition to common header vfio/pci: Enable peer-to-peer DMA transactions by default vfio/pci: Add dma-buf export support for MMIO regions Vivek Kasireddy (2): vfio: Export vfio device get and put registration helpers vfio/pci: Share the core device pointer while invoking feature functions block/blk-mq-dma.c | 7 +- drivers/iommu/dma-iommu.c | 4 +- drivers/pci/p2pdma.c | 154 ++++++++---- drivers/vfio/pci/Kconfig | 20 ++ drivers/vfio/pci/Makefile | 2 + drivers/vfio/pci/vfio_pci_config.c | 22 +- drivers/vfio/pci/vfio_pci_core.c | 59 +++-- drivers/vfio/pci/vfio_pci_dmabuf.c | 390 +++++++++++++++++++++++++++++ drivers/vfio/pci/vfio_pci_priv.h | 23 ++ drivers/vfio/vfio_main.c | 2 + include/linux/dma-buf.h | 1 + include/linux/pci-p2pdma.h | 114 +++++---- include/linux/types.h | 5 + include/linux/vfio.h | 2 + include/linux/vfio_pci_core.h | 4 + include/uapi/linux/vfio.h | 25 ++ kernel/dma/direct.c | 4 +- mm/hmm.c | 2 +- 18 files changed, 715 insertions(+), 125 deletions(-) create mode 100644 drivers/vfio/pci/vfio_pci_dmabuf.c -- 2.50.1

10 months, 2 weeks

[PATCH v11 0/9] TEE subsystem for protected dma-buf allocations

by Jens Wiklander

Hi, This patch set allocates the protected DMA-bufs from a DMA-heap instantiated from the TEE subsystem. The TEE subsystem handles the DMA-buf allocations since it is the TEE (OP-TEE, AMD-TEE, TS-TEE, or perhaps a future QTEE) which sets up the protection for the memory used for the DMA-bufs. The DMA-heap uses a protected memory pool provided by the backend TEE driver, allowing it to choose how to allocate the protected physical memory. The allocated DMA-bufs must be imported with a new TEE_IOC_SHM_REGISTER_FD before they can be passed as arguments when requesting services from the secure world. Three use-cases (Secure Video Playback, Trusted UI, and Secure Video Recording) have been identified so far to serve as examples of what can be expected. The use-cases have predefined DMA-heap names, "protected,secure-video", "protected,trusted-ui", and "protected,secure-video-record". The backend driver registers protected memory pools for the use-cases it supports. Each use-case has its own protected memory pool since different use-cases require isolation from different parts of the system. A protected memory pool can be based on a static carveout instantiated while probing the TEE backend driver, or dynamically allocated from CMA (dma_alloc_pages()) and made protected as needed by the TEE. This can be tested on a RockPi 4B+ with the following steps: repo init -u https://github.com/jenswi-linaro/manifest.git -m rockpi4.xml \ -b prototype/sdp-v11 repo sync -j8 cd build make toolchains -j$(nproc) make all -j$(nproc) # Copy ../out/rockpi4.img to an SD card and boot the RockPi from that # Connect a monitor to the RockPi # login and at the prompt: gst-launch-1.0 videotestsrc ! \ aesenc key=1f9423681beb9a79215820f6bda73d0f \ iv=e9aa8e834d8d70b7e0d254ff670dd718 serialize-iv=true ! \ aesdec key=1f9423681beb9a79215820f6bda73d0f ! \ kmssink The aesdec module has been hacked to use an OP-TEE TA to decrypt the stream into protected DMA-bufs which are consumed by the kmssink. The primitive QEMU tests from previous patch sets can be tested on RockPi in the same way using: xtest --sdp-basic The primitive tests are tested on QEMU with the following steps: repo init -u https://github.com/jenswi-linaro/manifest.git -m qemu_v8.xml \ -b prototype/sdp-v11 repo sync -j8 cd build make toolchains -j$(nproc) make SPMC_AT_EL=1 all -j$(nproc) make SPMC_AT_EL=1 run-only # login and at the prompt: xtest --sdp-basic The SPMC_AT_EL=1 parameter configures the build with FF-A and an SPMC at S-EL1 inside OP-TEE. The parameter can be changed to SPMC_AT_EL=n to test without FF-A using the original SMC ABI instead. Please remember to do %make arm-tf-clean for TF-A to be rebuilt properly using the new configuration. https://optee.readthedocs.io/en/latest/building/prerequisites.html list dependencies required to build the above. The primitive tests are pretty basic, mostly checking that a Trusted Application in the secure world can access and manipulate the memory. There are also some negative tests for out of bounds buffers, etc. Thanks, Jens Changes since V10: * Changed the new ABI OPTEE_MSG_CMD_GET_PROTMEM_CONFIG to report a list of u32 memory attributes instead of u16 endpoints to make room for both endpoint and access permissions in each entry. * In "tee: new ioctl to a register tee_shm from a dmabuf file descriptor", remove the unused path for DMA-bufs allocated by other means than the on in the TEE SS. * In "tee: implement protected DMA-heap", handle unloading of the backend driver module implementing the heap. The heap is reference counted and also calls tee_device_get() to guarantee that the module remains available while the heap is instantiated. * In "optee: support protected memory allocation", use dma_coerce_mask_and_coherent() instead of open-coding the function. * Added Sumit's R-B to - "optee: smc abi: dynamic protected memory allocation" - "optee: FF-A: dynamic protected memory allocation" - "optee: support protected memory allocation" - "tee: implement protected DMA-heap" - "dma-buf: dma-heap: export declared functions" Changes since V9: * Adding Sumit's R-B to "optee: sync secure world ABI headers" * Update commit message as requested for "dma-buf: dma-heap: export declared functions". * In "tee: implement protected DMA-heap": - add the hidden config option TEE_DMABUF_HEAPS to tell if the TEE subsystem can support DMA heaps - add a pfn_valid() to check that the passed physical address can be used by __pfn_to_page() and friends - remove the memremap() call, the caller is should do that instead if needed * In "tee: add tee_shm_alloc_dma_mem()" guard the calls to dma_alloc_pages() and dma_free_pages() with TEE_DMABUF_HEAPS to avoid linking errors in some configurations * In "optee: support protected memory allocation": - add the hidden config option OPTEE_STATIC_PROTMEM_POOL to tell if the driver can support a static protected memory pool - optee_protmem_pool_init() is slightly refactored to make the patches that follow easier - Call devm_memremap() before calling tee_protmem_static_pool_alloc() Changes since V8: * Using dma_alloc_pages() instead of cma_alloc() so the direct dependency on CMA can be removed together with the patches "cma: export cma_alloc() and cma_release()" and "dma-contiguous: export dma_contiguous_default_area". The patch * Renaming the patch "tee: add tee_shm_alloc_cma_phys_mem()" to "tee: add tee_shm_alloc_dma_mem()" * Setting DMA mask for the OP-TEE TEE device based on input from the secure world instead of relying on the parent device so following patches are removed: "tee: tee_device_alloc(): copy dma_mask from parent device" and "optee: pass parent device to tee_device_alloc()". * Adding Sumit Garg's R-B to "tee: refactor params_from_user()" * In the patch "tee: implement protected DMA-heap", map the physical memory passed to tee_protmem_static_pool_alloc(). Changes since V7: * Adding "dma-buf: dma-heap: export declared functions", "cma: export cma_alloc() and cma_release()", and "dma-contiguous: export dma_contiguous_default_area" to export the symbols needed to keep the TEE subsystem as a load module. * Removing CONFIG_TEE_DMABUF_HEAP and CONFIG_TEE_CMA since they aren't needed any longer. * Addressing review comments in "optee: sync secure world ABI headers" * Better align protected memory pool initialization between the smc-abi and ffa-abi parts of the optee driver. * Removing the patch "optee: account for direction while converting parameters" Changes since V6: * Restricted memory is now known as protected memory since to use the same term as https://docs.vulkan.org/guide/latest/protected.html. Update all patches to consistently use protected memory. * In "tee: implement protected DMA-heap" add the hidden config option TEE_DMABUF_HEAP to tell if the DMABUF_HEAPS functions are available for the TEE subsystem * Adding "tee: refactor params_from_user()", broken out from the patch "tee: new ioctl to a register tee_shm from a dmabuf file descriptor" * For "tee: new ioctl to a register tee_shm from a dmabuf file descriptor": - Update commit message to mention protected memory - Remove and open code tee_shm_get_parent_shm() in param_from_user_memref() * In "tee: add tee_shm_alloc_cma_phys_mem" add the hidden config option TEE_CMA to tell if the CMA functions are available for the TEE subsystem * For "tee: tee_device_alloc(): copy dma_mask from parent device" and "optee: pass parent device to tee_device_alloc", added Reviewed-by: Sumit Garg <sumit.garg(a)kernel.org> Changes since V5: * Removing "tee: add restricted memory allocation" and "tee: add TEE_IOC_RSTMEM_FD_INFO" * Adding "tee: implement restricted DMA-heap", "tee: new ioctl to a register tee_shm from a dmabuf file descriptor", "tee: add tee_shm_alloc_cma_phys_mem()", "optee: pass parent device to tee_device_alloc()", and "tee: tee_device_alloc(): copy dma_mask from parent device" * The two TEE driver OPs "rstmem_alloc()" and "rstmem_free()" are replaced with a struct tee_rstmem_pool abstraction. * Replaced the the TEE_IOC_RSTMEM_ALLOC user space API with the DMA-heap API Changes since V4: * Adding the patch "tee: add TEE_IOC_RSTMEM_FD_INFO" needed by the GStreamer demo * Removing the dummy CPU access and mmap functions from the dma_buf_ops * Fixing a compile error in "optee: FF-A: dynamic restricted memory allocation" reported by kernel test robot <lkp(a)intel.com> Changes since V3: * Make the use_case and flags field in struct tee_shm u32's instead of u16's * Add more description for TEE_IOC_RSTMEM_ALLOC in the header file * Import namespace DMA_BUF in module tee, reported by lkp(a)intel.com * Added a note in the commit message for "optee: account for direction while converting parameters" why it's needed * Factor out dynamic restricted memory allocation from "optee: support restricted memory allocation" into two new commits "optee: FF-A: dynamic restricted memory allocation" and "optee: smc abi: dynamic restricted memory allocation" * Guard CMA usage with #ifdef CONFIG_CMA, effectively disabling dynamic restricted memory allocate if CMA isn't configured Changes since the V2 RFC: * Based on v6.12 * Replaced the flags for SVP and Trusted UID memory with a u32 field with unique id for each use case * Added dynamic allocation of restricted memory pools * Added OP-TEE ABI both with and without FF-A for dynamic restricted memory * Added support for FF-A with FFA_LEND Changes since the V1 RFC: * Based on v6.11 * Complete rewrite, replacing the restricted heap with TEE_IOC_RSTMEM_ALLOC Changes since Olivier's post [2]: * Based on Yong Wu's post [1] where much of dma-buf handling is done in the generic restricted heap * Simplifications and cleanup * New commit message for "dma-buf: heaps: add Linaro restricted dmabuf heap support" * Replaced the word "secure" with "restricted" where applicable Etienne Carriere (1): tee: new ioctl to a register tee_shm from a dmabuf file descriptor Jens Wiklander (8): optee: sync secure world ABI headers dma-buf: dma-heap: export declared functions tee: implement protected DMA-heap tee: refactor params_from_user() tee: add tee_shm_alloc_dma_mem() optee: support protected memory allocation optee: FF-A: dynamic protected memory allocation optee: smc abi: dynamic protected memory allocation drivers/dma-buf/dma-heap.c | 3 + drivers/tee/Kconfig | 5 + drivers/tee/Makefile | 1 + drivers/tee/optee/Kconfig | 5 + drivers/tee/optee/Makefile | 1 + drivers/tee/optee/core.c | 7 + drivers/tee/optee/ffa_abi.c | 146 ++++++++- drivers/tee/optee/optee_ffa.h | 27 +- drivers/tee/optee/optee_msg.h | 84 ++++- drivers/tee/optee/optee_private.h | 15 +- drivers/tee/optee/optee_smc.h | 37 ++- drivers/tee/optee/protmem.c | 335 ++++++++++++++++++++ drivers/tee/optee/smc_abi.c | 141 ++++++++- drivers/tee/tee_core.c | 157 +++++++--- drivers/tee/tee_heap.c | 500 ++++++++++++++++++++++++++++++ drivers/tee/tee_private.h | 14 + drivers/tee/tee_shm.c | 157 +++++++++- include/linux/tee_core.h | 59 ++++ include/linux/tee_drv.h | 10 + include/uapi/linux/tee.h | 31 ++ 20 files changed, 1668 insertions(+), 67 deletions(-) create mode 100644 drivers/tee/optee/protmem.c create mode 100644 drivers/tee/tee_heap.c base-commit: 038d61fd642278bab63ee8ef722c50d10ab01e8f -- 2.43.0

10 months, 2 weeks

[PATCH v3 00/14] Rust abstractions for shmem-backed GEM objects

by Lyude Paul

This is the next version of the shmem backed GEM objects series originally from Asahi, previously posted by Daniel Almeida. Along with bindings for shmem backed GEM objects. This applies on top of Danilo and Abdiel's sgtable patches: https://lkml.org/lkml/2025/8/28/1018 Asahi Lina (2): rust: helpers: Add bindings/wrappers for dma_resv_lock rust: drm: gem: shmem: Add DRM shmem helper abstraction Lyude Paul (12): rust: drm: gem: Simplify use of generics rust: drm: gem: Add DriverFile type alias rust: drm: gem: Drop Object::SIZE rust: drm: gem: Support driver-private GEM object types rust: drm: gem: Add raw_dma_resv() function drm/gem/shmem: Extract drm_gem_shmem_init() from drm_gem_shmem_create() drm/gem/shmem: Extract drm_gem_shmem_release() from drm_gem_shmem_free() rust: gem: Introduce DriverObject::Args rust: drm: gem: Introduce SGTableRef rust: Add dma_buf stub bindings rust: drm: gem: Add export() callback rust: drm: gem: Add BaseObject::prime_export() drivers/gpu/drm/drm_gem_shmem_helper.c | 98 +++++-- drivers/gpu/drm/nova/driver.rs | 8 +- drivers/gpu/drm/nova/gem.rs | 15 +- include/drm/drm_gem_shmem_helper.h | 2 + rust/bindings/bindings_helper.h | 3 + rust/helpers/dma-resv.c | 13 + rust/helpers/drm.c | 48 +++- rust/helpers/helpers.c | 1 + rust/kernel/dma_buf.rs | 39 +++ rust/kernel/drm/device.rs | 17 +- rust/kernel/drm/driver.rs | 5 +- rust/kernel/drm/gem/mod.rs | 274 +++++++++++++++---- rust/kernel/drm/gem/shmem.rs | 365 +++++++++++++++++++++++++ rust/kernel/lib.rs | 1 + 14 files changed, 783 insertions(+), 106 deletions(-) create mode 100644 rust/helpers/dma-resv.c create mode 100644 rust/kernel/dma_buf.rs create mode 100644 rust/kernel/drm/gem/shmem.rs base-commit: 09f90256e8902793f594517ef440698585eb3595 prerequisite-patch-id: 0e1b1f9a665317ff569a37df6ff49cd1880b04f8 prerequisite-patch-id: 178b864e6d1b88ee299dcc05d1a7a4c89ec7ed51 prerequisite-patch-id: 7f72c4bfd0e5f50b6d2f8ce96751782894a3ba81 prerequisite-patch-id: 62fa6de7d3ae99dc54c092087bd716e6749545fd prerequisite-patch-id: 3d14d56ca93b0831837aa26b802100a250adeac6 prerequisite-patch-id: 7a12f4b0e7588874ce589b41b70671dc261b9468 prerequisite-patch-id: c44763ec35c4e4431e769df088b98424cbddf7df prerequisite-patch-id: a9e008c179b1c2fbe76654a191e5018880383d49 prerequisite-patch-id: 1e9ce500ce25188c575be608cd39e15a59836f83 prerequisite-patch-id: 39ca3a210a6c365434924c07a0c98a074eb73b97 prerequisite-patch-id: a747e05834cdb8b8f727e1f7c8b110c636cadab8 prerequisite-patch-id: 24833689bdecd3fc7a604e13bfe203ccd2fca6f0 -- 2.50.0

10 months, 3 weeks

Re: [PATCH v8 09/11] qcomtee: add primordial object

by Bjorn Andersson

On Wed, Aug 20, 2025 at 04:38:56PM -0700, Amirreza Zarrabi wrote: Looking at other commits in drivers/tee/ I'd expect the subject prefix to be "tee: qcom: ". > After booting, the kernel provides a static object known as the > primordial object. This object is utilized by QTEE for native > kernel services such as yield or privileged operations. > > Acked-by: Sumit Garg <sumit.garg(a)oss.qualcomm.com> > Tested-by: Neil Armstrong <neil.armstrong(a)linaro.org> > Tested-by: Harshal Dev <quic_hdev(a)quicinc.com> > Signed-off-by: Amirreza Zarrabi <amirreza.zarrabi(a)oss.qualcomm.com> > --- > drivers/tee/qcomtee/Makefile | 1 + > drivers/tee/qcomtee/core.c | 19 ++++++++--- > drivers/tee/qcomtee/primordial_obj.c | 66 ++++++++++++++++++++++++++++++++++++ > drivers/tee/qcomtee/qcomtee.h | 3 ++ > 4 files changed, 84 insertions(+), 5 deletions(-) > > diff --git a/drivers/tee/qcomtee/Makefile b/drivers/tee/qcomtee/Makefile > index 600af2b8f1c1..78f8e899d143 100644 > --- a/drivers/tee/qcomtee/Makefile > +++ b/drivers/tee/qcomtee/Makefile > @@ -3,5 +3,6 @@ obj-$(CONFIG_QCOMTEE) += qcomtee.o > qcomtee-objs += async.o > qcomtee-objs += call.o > qcomtee-objs += core.o > +qcomtee-objs += primordial_obj.o > qcomtee-objs += shm.o > qcomtee-objs += user_obj.o > diff --git a/drivers/tee/qcomtee/core.c b/drivers/tee/qcomtee/core.c > index 578299a3eabc..561a48319f91 100644 > --- a/drivers/tee/qcomtee/core.c > +++ b/drivers/tee/qcomtee/core.c > @@ -31,10 +31,12 @@ int qcomtee_next_arg_type(struct qcomtee_arg *u, int i, > } > > /* > - * QTEE expects IDs with the QCOMTEE_MSG_OBJECT_NS_BIT set for objects > - * of the QCOMTEE_OBJECT_TYPE_CB type. > + * QTEE expects IDs with QCOMTEE_MSG_OBJECT_NS_BIT set for objects of > + * QCOMTEE_OBJECT_TYPE_CB type. The first ID with QCOMTEE_MSG_OBJECT_NS_BIT > + * set is reserved for the primordial object. > */ > -#define QCOMTEE_OBJECT_ID_START (QCOMTEE_MSG_OBJECT_NS_BIT + 1) > +#define QCOMTEE_OBJECT_PRIMORDIAL (QCOMTEE_MSG_OBJECT_NS_BIT) > +#define QCOMTEE_OBJECT_ID_START (QCOMTEE_OBJECT_PRIMORDIAL + 1) > #define QCOMTEE_OBJECT_ID_END (U32_MAX) > > #define QCOMTEE_OBJECT_SET(p, type, ...) \ > @@ -157,7 +159,9 @@ static void qcomtee_object_release(struct kref *refcount) > */ > int qcomtee_object_get(struct qcomtee_object *object) > { > - if (object != NULL_QCOMTEE_OBJECT && object != ROOT_QCOMTEE_OBJECT) > + if (object != &qcomtee_primordial_object && > + object != NULL_QCOMTEE_OBJECT && > + object != ROOT_QCOMTEE_OBJECT) > return kref_get_unless_zero(&object->refcount); > > return 0; > @@ -169,7 +173,9 @@ int qcomtee_object_get(struct qcomtee_object *object) > */ > void qcomtee_object_put(struct qcomtee_object *object) > { > - if (object != NULL_QCOMTEE_OBJECT && object != ROOT_QCOMTEE_OBJECT) > + if (object != &qcomtee_primordial_object && > + object != NULL_QCOMTEE_OBJECT && > + object != ROOT_QCOMTEE_OBJECT) > kref_put(&object->refcount, qcomtee_object_release); > } > > @@ -261,6 +267,9 @@ qcomtee_local_object_get(struct qcomtee_object_invoke_ctx *oic, > struct qcomtee *qcomtee = tee_get_drvdata(oic->ctx->teedev); > struct qcomtee_object *object; > > + if (object_id == QCOMTEE_OBJECT_PRIMORDIAL) > + return &qcomtee_primordial_object; > + > guard(rcu)(); > object = xa_load(&qcomtee->xa_local_objects, object_id); > /* It already checks for %NULL_QCOMTEE_OBJECT. */ > diff --git a/drivers/tee/qcomtee/primordial_obj.c b/drivers/tee/qcomtee/primordial_obj.c > new file mode 100644 > index 000000000000..df94fbf5f141 > --- /dev/null > +++ b/drivers/tee/qcomtee/primordial_obj.c > @@ -0,0 +1,66 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries. > + */ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt I don't see any pr_*() functions in this file, please drop this. Regards, Bjorn > + > +#include <linux/delay.h> > + > +#include "qcomtee.h" > + > +/** > + * DOC: Primordial Object > + * > + * After boot, the kernel provides a static object of type > + * %QCOMTEE_OBJECT_TYPE_CB called the primordial object. This object is used > + * for native kernel services or privileged operations. > + * > + * We support: > + * - %QCOMTEE_OBJECT_OP_YIELD to yield by the thread running in QTEE. > + * - %QCOMTEE_OBJECT_OP_SLEEP to wait for a period of time. > + */ > + > +#define QCOMTEE_OBJECT_OP_YIELD 1 > +#define QCOMTEE_OBJECT_OP_SLEEP 2 > + > +static int > +qcomtee_primordial_obj_dispatch(struct qcomtee_object_invoke_ctx *oic, > + struct qcomtee_object *primordial_object_unused, > + u32 op, struct qcomtee_arg *args) > +{ > + int err = 0; > + > + switch (op) { > + case QCOMTEE_OBJECT_OP_YIELD: > + cond_resched(); > + /* No output object. */ > + oic->data = NULL; > + break; > + case QCOMTEE_OBJECT_OP_SLEEP: > + /* Check message format matched QCOMTEE_OBJECT_OP_SLEEP op. */ > + if (qcomtee_args_len(args) != 1 || > + args[0].type != QCOMTEE_ARG_TYPE_IB || > + args[0].b.size < sizeof(u32)) > + return -EINVAL; > + > + msleep(*(u32 *)(args[0].b.addr)); > + /* No output object. */ > + oic->data = NULL; > + break; > + default: > + err = -EINVAL; > + } > + > + return err; > +} > + > +static struct qcomtee_object_operations qcomtee_primordial_obj_ops = { > + .dispatch = qcomtee_primordial_obj_dispatch, > +}; > + > +struct qcomtee_object qcomtee_primordial_object = { > + .name = "primordial", > + .object_type = QCOMTEE_OBJECT_TYPE_CB, > + .ops = &qcomtee_primordial_obj_ops > +}; > diff --git a/drivers/tee/qcomtee/qcomtee.h b/drivers/tee/qcomtee/qcomtee.h > index f34be992e68b..084b3882017e 100644 > --- a/drivers/tee/qcomtee/qcomtee.h > +++ b/drivers/tee/qcomtee/qcomtee.h > @@ -140,4 +140,7 @@ int qcomtee_user_object_submit(struct tee_context *ctx, > struct tee_param *params, int num_params, > int req_id, int errno); > > +/* (2) Primordial Object. */ > +extern struct qcomtee_object qcomtee_primordial_object; > + > #endif /* QCOMTEE_H */ > > -- > 2.34.1 >

10 months, 3 weeks

Re: [PATCH v8 06/11] firmware: qcom: scm: add support for object invocation

by Bjorn Andersson

On Wed, Aug 20, 2025 at 04:38:53PM -0700, Amirreza Zarrabi wrote: > diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c [..] > +static void qcom_scm_qtee_free(void *data) > +{ > + struct platform_device *qtee_dev = data; > + > + platform_device_unregister(qtee_dev); > +} > + > +static int qcom_scm_qtee_init(struct qcom_scm *scm) > +{ > + struct platform_device *qtee_dev; > + u64 result, response_type; > + int ret; > + > + /* > + * Check if QTEE supports smcinvoke: > + * This will fail due to invalid buffers, but first, it checks whether > + * the call is supported in QTEE syscall handler. > + * If not supported, -EIO is returned. > + */ > + ret = qcom_scm_qtee_invoke_smc(0, 0, 0, 0, &result, &response_type); > + if (ret == -EIO) > + return -EIO; > + > + /* Setup QTEE interface device. */ > + qtee_dev = platform_device_alloc("qcomtee", -1); > + if (!qtee_dev) > + return -ENOMEM; > + > + qtee_dev->dev.parent = scm->dev; > + > + ret = platform_device_add(qtee_dev); > + if (ret) { > + platform_device_put(qtee_dev); > + return ret; > + } Wouldn't this work instead of the alloc + parent + add? qtee_dev = platform_device_alloc_data(scm->dev, "qcomtee", -1, NULL, 0); if (IS_ERR(qtee_dev)) return PTR_ERR(qtee_dev); > + > + return devm_add_action_or_reset(scm->dev, qcom_scm_qtee_free, qtee_dev); > +} > + > /** > * qcom_scm_is_available() - Checks if SCM is available > */ > @@ -2326,6 +2450,16 @@ static int qcom_scm_probe(struct platform_device *pdev) > ret = qcom_scm_qseecom_init(scm); > WARN(ret < 0, "failed to initialize qseecom: %d\n", ret); > > + /* > + * Initialize the QTEE object interface. > + * > + * This only represents the availability for QTEE object invocation > + * and callback support. On failure, ignore the result. Any subsystem > + * depending on it may fail if it tries to access this interface. > + */ > + ret = qcom_scm_qtee_init(scm); > + dev_warn_probe(scm->dev, ret, "Failed to initialize qcomtee\n"); A successful boot of db410c (APQ8016) now has the following in the log: [ 0.161437] qcom_scm firmware:scm: error -EIO: Failed to initialize qcomtee If the target doesn't implement qtee, I'd expect that you tell me that - or preferably stay silent. Looking at the other error conditions, we find -ENOMEM, for which you should also avoid printing. In fact, I believe all other error paths of qcom_scm_qtee_init() will have printed an error already (if not, please move the error print to the place(s) where it's needed). As you're ignoring the return value, please then also change the return type of the function to void. Regards, Bjorn > + > return 0; > }

10 months, 3 weeks

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

Linaro-mm-sig August 2025