Linaro-mm-sig May 2026

linaro-mm-sig@lists.linaro.org

107 participants
351 discussions

[PATCH] dma-buf: set SB_I_NOEXEC on the pseudo filesystem

by John Hubbard

The dma-buf pseudo filesystem dispenses S_ANON_INODE inodes via alloc_anon_inode() but never sets SB_I_NOEXEC on its superblock. Since commit 1e7ab6f67824 ("anon_inode: rework assertions") in 6.17, path_noexec() warns on exactly that combination, so an mmap() on any dma-buf fd trips the warning: WARNING: CPU: 11 PID: 121813 at fs/exec.c:118 path_noexec+0x47/0x50 do_mmap+0x2b5/0x680 vm_mmap_pgoff+0x129/0x210 ksys_mmap_pgoff+0x177/0x240 __x64_sys_mmap+0x33/0x70 dma-bufs have no business being executable, which is the invariant that the new assertion is enforcing. Set SB_I_NOEXEC on the dmabuf superblock. Reproducer on a CONFIG_DEBUG_VFS=y kernel: make -C tools/testing/selftests/dmabuf-heaps sudo ./tools/testing/selftests/dmabuf-heaps/dmabuf-heap -t system The selftest allocates from /dev/dma_heap/system and mmaps the returned fd, which trips the warning without this patch. Fixes: 1e7ab6f67824 ("anon_inode: rework assertions") Cc: stable(a)vger.kernel.org Signed-off-by: John Hubbard <jhubbard(a)nvidia.com> --- drivers/dma-buf/dma-buf.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 71f37544a5c6..d86a99d7b8dc 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -216,6 +216,7 @@ static int dma_buf_fs_init_context(struct fs_context *fc) if (!ctx) return -ENOMEM; ctx->dops = &dma_buf_dentry_ops; + fc->s_iflags |= SB_I_NOEXEC; return 0; } -- 2.54.0

2 months

World’s Best Licensed Blockchain Recovery Companies in 2026

by carbideinfos＠gmail.com

Victim of cryptocurrency fraud or wallet compromise? JimRecoveryTeam provides professional, confidential investigations for stolen or misused digital assets. No upfront costs involved. WhatsApp: +1 929 399 9264 | Website: https://jimrecoveryteam.online | Email: info(a)jimrecoveryteam.online

2 months

Chasing digital trails: Thoughts on JimRecoveryTeam?

by carbideinfos＠gmail.com

JimRecoveryTeam offers trusted crypto fraud investigation services designed to assist victims of wallet hacks, online scams, and digital currency theft. Confidential assistance with zero upfront fees. WhatsApp: +1 929 399 9264 | Website: https://jimrecoveryteam.online | Email: info(a)jimrecoveryteam.online

2 months

[PATCH v5 0/4] dma-buf: heaps: Turn heaps into modules

by Maxime Ripard

Hi, The recent introduction of heaps in the optee driver [1] made possible the creation of heaps as modules. It's generally a good idea if possible, including for the already existing system and CMA heaps. The system one is pretty trivial, the CMA is now easy too with the reworks we got in 7.1-r1. Let me know what you think, Maxime 1: https://lore.kernel.org/dri-devel/20250911135007.1275833-4-jens.wiklander@l… Signed-off-by: Maxime Ripard <mripard(a)kernel.org> --- Changes in v5: - Rebase on 7.1-rc1 - Add a patch to enable the heaps in arm64 defconfig - Link to v4: https://lore.kernel.org/r/20260331-dma-buf-heaps-as-modules-v4-0-e18fda5044… Changes in v4: - Fix compilation failure - Rework to take into account OF_RESERVED_MEM - Fix regression making the default CMA area disappear if not created through the DT - Added some documentation and comments - Link to v3: https://lore.kernel.org/r/20260303-dma-buf-heaps-as-modules-v3-0-24344812c7… Changes in v3: - Squashed cma_get_name and cma_alloc/release patches - Fixed typo in Export dev_get_cma_area commit title - Fixed compilation failure with DMA_CMA but not OF_RESERVED_MEM - Link to v2: https://lore.kernel.org/r/20260227-dma-buf-heaps-as-modules-v2-0-454aee7e06… Changes in v2: - Collect tags - Don't export dma_contiguous_default_area anymore, but export dev_get_cma_area instead - Mentioned that heap modules can't be removed - Link to v1: https://lore.kernel.org/r/20260225-dma-buf-heaps-as-modules-v1-0-2109225a09… --- Maxime Ripard (4): dma-buf: heaps: Export mem_accounting parameter dma-buf: heaps: cma: Turn the heap into a module dma-buf: heaps: system: Turn the heap into a module arm64: defconfig: Enable dma-buf heaps arch/arm64/configs/defconfig | 3 +++ drivers/dma-buf/dma-heap.c | 1 + drivers/dma-buf/heaps/Kconfig | 4 ++-- drivers/dma-buf/heaps/cma_heap.c | 3 +++ drivers/dma-buf/heaps/system_heap.c | 5 +++++ 5 files changed, 14 insertions(+), 2 deletions(-) --- base-commit: 5e9b7d093f3f77cb0af4409559e3d139babfb443 change-id: 20260225-dma-buf-heaps-as-modules-1034b3ec9f2a Best regards, -- Maxime Ripard <mripard(a)kernel.org>

2 months

[PATCH 0/2] dma-buf: add DMA_BUF_IOCTL_DERIVE for reduced-permission aliases

by Albert Esteve

When sharing a dma-buf between components of different trust levels, the allocator may need to hand a consumer a read-only view of a buffer it holds with read-write access. An example is a camera pipeline where the capture component writes frames into a buffer and needs to pass a read-only handle to a downstream processing component that should not be able to modify the data. However, no such mechanism exists today. The access mode of a dma-buf file descriptor is fixed at export time, and the standard POSIX interfaces for duplicating or changing file descriptors (i.e., dup(2), dup3(2), and fcntl(F_SETFL)) cannot alter the read/write access mode of the copy. One natural candidate would be reopening via /proc/self/fd/<N> with O_RDONLY, which works for regular files. For dma-buf this would fail (that is, if we were to add a new handler for open f_op) with ENXIO because the dmabuf pseudo-filesystem carries SB_NOUSER, which prevents the VFS from opening its files through path-based resolution from userspace. Alternatively, exporting the buffer twice would produce two independent dma_buf instances, which breaks fence synchronization. Therefore we add a new DMA_BUF_IOCTL_DERIVE ioctl, which produces a new file descriptor for an existing dma-buf with a caller-specified subset of the original permissions: ``` struct dma_buf_derive { __u32 flags; __s32 fd; }; struct dma_buf_derive req = { .flags = O_RDONLY | O_CLOEXEC }; ioctl(rw_fd, DMA_BUF_IOCTL_DERIVE, &req); /* req.fd is now a read-only alias of the same buffer */ ``` Permission escalation is rejected with -EACCES. The new fd aliases the same struct dma_buf as the original, same dma_resv, same exporter ops, same underlying memory; so importers attaching to either fd see the same fence timeline and operate on the same object. Access control for which components may receive or pass on restricted descriptors can be layered on top via SELinux file:read and file:write permissions. A shared writable mapping (PROT_WRITE | MAP_SHARED) on the read-only fd is rejected with -EACCES in dma_buf_mmap_internal(). Two small internal adjustments accompany the ioctl: - __dma_buf_list_del() is moved to dma_buf_release() so it fires exactly once on dentry destruction rather than on every file close. - dma_buf_file_release() is updated to call dma_buf_put() only for files that are not the primary dma-buf file. This may not be the best approach, but after considering different options and alternatives (as described above), we decided to raise the discussion upstream. Thus, we welcome any alternative proposal or ideas. The series is structured as: - Patch 1 adds the new ioctl implementation. - Patch 2 adds selftests covering the new ioctl. Signed-off-by: Albert Esteve <aesteve(a)redhat.com> --- Albert Esteve (2): dma-buf: add DMA_BUF_IOCTL_DERIVE for reduced-permission aliases selftests: dma-buf: add DERIVE ioctl tests drivers/dma-buf/dma-buf.c | 58 ++++++++++- include/uapi/linux/dma-buf.h | 28 +++++ tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c | 114 ++++++++++++++++++++- 3 files changed, 198 insertions(+), 2 deletions(-) --- base-commit: ab5fce87a778cb780a05984a2ca448f2b41aafbf change-id: 20260520-dmabuf-limit-access-73261353841a Best regards, -- Albert Esteve <aesteve(a)redhat.com>

2 months

[PATCH 0/6] drm/panthor: Use guards

by Boris Brezillon

Turn the mixed bag of manual locks and guards into something more consistent. This patchset takes care of locks that already have guards available, but also adds new guards for resv, drm_dev_enter/exit and the custom panthor_device_resume_and_get() helper we have around runtime PM. I've intentionally placed the patch transition all locks with readily available guards first so we can merge it even if the new guards face some controversy. Signed-off-by: Boris Brezillon <boris.brezillon(a)collabora.com> --- Boris Brezillon (6): drm/panthor: Driver-wide xxx_[un]lock -> [scoped_]guard replacement dma-resv: Define guards for context-less dma_resv locks drm: Define a conditional guard for drm_dev_{enter,exit}() drm/panthor: Use guards for resv locking drm/panthor: Use the drm_dev_access guard drm/panthor: Add a new guard for our custom resume_and_get() PM helper drivers/gpu/drm/panthor/panthor_devfreq.c | 29 +- drivers/gpu/drm/panthor/panthor_device.c | 163 +++++----- drivers/gpu/drm/panthor/panthor_device.h | 10 +- drivers/gpu/drm/panthor/panthor_drv.c | 62 ++-- drivers/gpu/drm/panthor/panthor_gem.c | 102 +++---- drivers/gpu/drm/panthor/panthor_gpu.c | 40 +-- drivers/gpu/drm/panthor/panthor_heap.c | 139 ++++----- drivers/gpu/drm/panthor/panthor_mmu.c | 480 ++++++++++++++---------------- drivers/gpu/drm/panthor/panthor_pwr.c | 8 +- drivers/gpu/drm/panthor/panthor_sched.c | 254 ++++++++-------- include/drm/drm_drv.h | 9 + include/linux/dma-resv.h | 5 + 12 files changed, 589 insertions(+), 712 deletions(-) --- base-commit: ac5ac0acf11df04295eb1811066097b7022d6c7f change-id: 20260512-panthor-guard-refactor-f1c6bc30c321 prerequisite-message-id: 20260512-panthor-signal-from-irq-v2-0-95c614a739cb(a)collabora.com prerequisite-patch-id: e3cfd6399b2dc5439687932c6e961d845369562a prerequisite-patch-id: 79820e6740c0c456efc1dfa273de04e495515a1c prerequisite-patch-id: a3611a7c9551c606aaf87125782e6d18b6a6549e prerequisite-patch-id: 6e9dc83a60e53e7b0d84030727ad9b1921e4b2ca prerequisite-patch-id: eabd36064a01418a6ada3176b996a4038a314c21 prerequisite-patch-id: ca3a30182b71bf66c51ed2b6411d7ed8dc761c8e prerequisite-patch-id: 6e549dd0ee9e3e0c8866da72dcabc82209d88360 prerequisite-patch-id: 5217700df7026ef533a2f273ea2535f9fc1274ac prerequisite-patch-id: 8d57abec9f92bcbb21108d3005805b7c155a48f6 prerequisite-patch-id: 0bf98de955fce577ff8d4fb82c02dc04684beca6 prerequisite-patch-id: a9e0d90a64dfd5950a69b857af3867404be1ab45 Best regards, -- Boris Brezillon <boris.brezillon(a)collabora.com>

2 months

4mmc best quality for sale WhatsApp +33605825265

by takulopez45＠gmail.com

4mmc best quality for sale WhatsApp +33605825265 3mmc best quality for sale WhatsApp +33605825265 We offer a wide range of products from the best laboratories in the world. All our products are 100% original and delivered worldwide at affordable prices. Contact details. WhatsApp +33605825265 E-mail: cryvojaserty(a)gmail.com after registering their products, customers can track their shipment online and know its current location, until it reaches the addressee. Our products are characterized by purity from 98 to 99%. For questions about our products, please contact us. Contact details. WhatsApp +33605825265 Email .. cryvojaserty(a)gmail.com Buy 4MMC Online|4MMC For Sale|Order 4MMC Online.. WhatsApp +33605825265 Buy 6apb, 4mmc, 5mapb, MDMA, Coke, Ketamine ... WhatsApp +33605825265 buy crystal meth online, buy meth online, how to buy cheap meth online, buy methamphetamine for personal use, buy MDPV online, buy cheap meth online, buy cheap methylone online, buy amphetamine tablets online, buy methylone online, buy MDMA online, how to buy cheap amphetamines online, concert for sale online, cheap concerts online buy meth online, methamphetamine for sale, lisdexamfetamine used to treat ADHD for sale online Contact details. WhatsApp +33605825265 Email .. cryvojaserty(a)gmail.com Each product has its own unique properties. We import directly from factory, so we can guarantee high quality product with purity over 99.9%. We are one of the safest and most trusted sellers of mephedrone, methylone, amphetamines, MDAI, 4- Buy weight loss medications: Mounjaro, Ozempic, Wegovy, Saxenda Buy weight loss medications without a prescription Buy Mounjaro, Buy Ozempic, What is the most effective weight loss remedy available over the counter? What is the most effective weight loss drug? Ketamine HCl 200 mg/ml, solution for injection, 10 ml Where to buy ketamine HCL 200 mg/ml Contact details. WhatsApp +33605825265 Email .. cryvojaserty(a)gmail.com Ketamine Sale Online ..WhatsApp +33605825265 Ketamine hydrochloride injection 50 mg Buy ketamine online with delivery via PayPal Ketamine hydrochloride injection 50 mg, 10 ml vial BUY COKE, XANAX, ADDERALL, ESTACY, METH, AMPHETAMINE SPEED, OXY 80 MG, COCAINE, MDMA WhatsApp +33605825265 Buy Ketamine, Nembutal, Adderall Online: WhatsApp +33605825265 ,Buy Xanax 2 mg Online, Buy Painkillers, Buy Ozempic, Buy Sexanda Online, Buy Abortion Pills Online, Buy Xanax, Buy Wegovy | MDMA, 2CB, A-PVP, 3CMC | OZEMPIC | STEROIDS (ECT/Nembutal) | Heroin, cocaine. Buy Xanax Online, Buy Painkillers Online, Buy Nembutal Online, Buy Anxiety Pills Online Contact details. WhatsApp +33605825265 Email .. cryvojaserty(a)gmail.com

2 months

[PATCH 00/12] misc/syncobj: add /dev/syncobj device

by Julian Orth

This series adds a new device /dev/syncobj that can be used to create and manipulate DRM syncobjs. Previously, these operations required the use of a DRM device and the device needed to support the DRIVER_SYNCOBJ and DRIVER_SYNCOBJ_TIMELINE features. There are several issues with the existing API: - Syncobjs are the only explicit sync mechanism available on wayland. Most compositors do not use GPU waits. Instead, they use the DRM_IOCTL_SYNCOBJ_EVENTFD ioctl to perform a CPU wait. Being tied to DRM devices means that compositors cannot consistently offer this feature even though no device-specific logic is involved. - llvmpipe currently cannot offer syncobj interop because it does not have access to a DRM device. This means that applications using llvmpipe cannot present images before they have finished rendering, despite llvmpipe using threaded rendering. - Clients that do not use the Vulkan WSI need to manually probe /dev/dri for devices that support the syncobj ioctls in order to use the wayland syncobj protocol. - Similarly, clients that want to use screen capture have no equivalent to the WSI and are therefore forced into that path. - Having to keep a DRM device open has potentially negative interactions with GPU hotplug. - Having to translate between syncobj FDs and handles is troublesome in the compositor usecase since syncobjs come and go frequently and need to be cleaned up when clients disconnect. /dev/syncobj solves these issues by providing all syncobj ioctls under a consistent path that is not tied to any DRM device. It also operates directly on file descriptors instead of syncobj handles. The series starts with a number of small refactorings in drm_syncobj.c to make its functionality available outside of the file and without the need for drm_file/handle pairs. The last commit adds the /dev/syncobj module. I've added it as a misc device but maybe this should instead live somewhere under gpu/drm. An application using the new interface can be found at [1]. [1]: https://github.com/mahkoh/jay/pull/947 --- Julian Orth (12): drm/syncobj: add drm_syncobj_from_fd drm/syncobj: add drm_syncobj_fence_lookup drm/syncobj: make drm_syncobj_array_wait_timeout public drm/syncobj: add drm_syncobj_register_eventfd drm/syncobj: have transfer functions accept drm_syncobj directly drm/syncobj: add drm_syncobj_transfer drm/syncobj: add drm_syncobj_timeline_signal drm/syncobj: add drm_syncobj_query drm/syncobj: fix resource leak in drm_syncobj_import_sync_file_fence drm/syncobj: add drm_syncobj_import_sync_file drm/syncobj: add drm_syncobj_export_sync_file misc/syncobj: add new device Documentation/userspace-api/ioctl/ioctl-number.rst | 1 + drivers/gpu/drm/drm_syncobj.c | 374 ++++++++++++++----- drivers/misc/Kconfig | 10 + drivers/misc/Makefile | 1 + drivers/misc/syncobj.c | 404 +++++++++++++++++++++ include/drm/drm_syncobj.h | 21 ++ include/uapi/linux/syncobj.h | 75 ++++ 7 files changed, 795 insertions(+), 91 deletions(-) --- base-commit: 6916d5703ddf9a38f1f6c2cc793381a24ee914c6 change-id: 20260516-jorth-syncobj-d4d374c8c61b Best regards, -- Julian Orth <ju.orth(a)gmail.com>

2 months

[PATCH] dma-buf: system_heap: Use LIST_HEAD() to initialize on stack list head

by Jisheng Zhang

Use LIST_HEAD to initialize on stack list head. No intentional functional impact. Change generated with below coccinelle script: @@ identifier name; @@ - struct list_head name; + LIST_HEAD(name); ... when != name - INIT_LIST_HEAD(&name); Signed-off-by: Jisheng Zhang <jszhang(a)kernel.org> --- drivers/dma-buf/heaps/system_heap.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c index 03c2b87cb111..6f8b7138ff56 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -409,7 +409,7 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap, struct dma_buf *dmabuf; struct sg_table *table; struct scatterlist *sg; - struct list_head pages; + LIST_HEAD(pages); struct page *page, *tmp_page; int i, ret = -ENOMEM; @@ -423,7 +423,6 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap, buffer->len = len; buffer->cc_shared = cc_shared; - INIT_LIST_HEAD(&pages); i = 0; while (size_remaining > 0) { /* -- 2.53.0

2 months, 1 week

[PATCH RFC 0/5] memcg: dma-buf per-cgroup accounting via pid_fd

by Albert Esteve

This RFC builds on T.J. Mercier's earlier series [1] which added a memory.stat counter for exported dma-bufs and a binder-backed mechanism to transfer charges between cgroups. The first commit is taken almost verbatim from TJ's series: it introduces MEMCG_DMABUF as a dedicated per-cgroup stat, so that the total exported dma-buf footprint is visible both system-wide (via the root cgroup) and per-application (via per-process cgroups). This avoids the overhead of DMABUF_SYSFS_STATS and integrates naturally into the existing cgroup memory hierarchy. The rest of the series departs from TJ's approach. While the first commit introduces the memcg stat infrastructure for dmabufs, the export-time charging it introduces in dma_buf_export() is then superseded: we charge at dma_heap_ioctl_allocate() time, using a new charge_pid_fd field in struct dma_heap_allocation_data. The allocator opens a pidfd for its client (e.g., from binder's sender_pid), passes it to the ioctl, and the kernel charges the buffer directly to the client's cgroup at allocation time, so no transfer step is needed. This decouples the accounting path from binder entirely: any allocator that knows its client's PID can use the pid_fd mechanism regardless of the IPC transport in use. The cross-cgroup charging capability requires access control. Patches #3 and #4 add a generic LSM hook (security_dma_heap_alloc) and an SELinux implementation based on a new dma_heap object class with a charge_to permission, so policy authors can express which domains are allowed to charge memory to another domain's cgroup. Last patch adds some tests to verify the new charge_pid_fd field. We are sending it as an RFC to spark broader discussion. It may or may not be the right path forward, and we welcome feedback on the trade-offs. Collision note: Eric Chanudet's series [2] adds __GFP_ACCOUNT to system_heap page allocations as an opt-in module parameter. That approach charges pages to the allocator's own kmem, which overlaps with MEMCG_DMABUF. This series explicitly removes __GFP_ACCOUNT from system heap allocations and routes all accounting through the MEMCG_DMABUF path to avoid double-counting. [1] https://lore.kernel.org/cgroups/20230109213809.418135-1-tjmercier@google.co… [2] https://lore.kernel.org/r/20260113-dmabuf-heap-system-memcg-v2-0-e85722cc2f… Signed-off-by: Albert Esteve <aesteve(a)redhat.com> --- Albert Esteve (4): dma-heap: charge dma-buf memory via explicit memcg security: dma-heap: Add dma_heap_alloc LSM hook selinux: Restrict cross-cgroup dma-heap charging selftests/dmabuf-heaps: Add dma-buf memcg accounting tests T.J. Mercier (1): memcg: Track exported dma-buffers Documentation/admin-guide/cgroup-v2.rst | 5 + drivers/dma-buf/dma-buf.c | 7 + drivers/dma-buf/dma-heap.c | 54 +++++- drivers/dma-buf/heaps/system_heap.c | 2 - include/linux/dma-buf.h | 4 + include/linux/lsm_hook_defs.h | 1 + include/linux/memcontrol.h | 37 ++++ include/linux/security.h | 7 + include/uapi/linux/dma-heap.h | 6 + mm/memcontrol.c | 19 ++ security/security.c | 16 ++ security/selinux/hooks.c | 7 + security/selinux/include/classmap.h | 1 + tools/testing/selftests/cgroup/Makefile | 2 +- tools/testing/selftests/cgroup/test_memcontrol.c | 143 +++++++++++++- tools/testing/selftests/dmabuf-heaps/config | 1 + tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c | 126 ++++++++++++- tools/testing/selftests/dmabuf-heaps/vmtest.sh | 205 +++++++++++++++++++++ 18 files changed, 633 insertions(+), 10 deletions(-) --- base-commit: 74fe02ce122a6103f207d29fafc8b3a53de6abaf change-id: 20260508-v2_20230123_tjmercier_google_com-f44fcfb16530 Best regards, -- Albert Esteve <aesteve(a)redhat.com>

2 months, 1 week

← Newer
1
...
6
7
8
9
10
11
12
...
36
Older →

Jump to page:

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

Linaro-mm-sig May 2026