kernel/git/stable/linux.git/Documentation/userspace-api, branch linux-5.15.y

media: v4l2-ctrls: Allow unknown HDR10 white point and luminance

2026-09-14T11:20:21+00:00

commit 49af0c7cad889f7dabe5cf080b019392066122a3 upstream. SMPTE ST 2086 defines the nominal ranges for mastering display chromaticity and luminance values. Its Annex A also documents that CTA 861-G uses zero maximum and minimum luminance values to signal that the corresponding values are unknown, and the xy chromaticity coordinate (0, 0) to signal that the white point chromaticity is unknown. The V4L2 HDR10 mastering display compound control currently rejects these values. Consequently, an unknown white point or luminance value prevents the entire compound control from being updated, making the other valid mastering display metadata unavailable to userspace. Accept (0, 0) as an unknown white point and zero as an unknown maximum or minimum mastering luminance. Continue to reject partially zero white point coordinates and non-zero values outside the nominal ranges. Display primary validation remains unchanged. Document the newly accepted unknown values in the V4L2 userspace API. Fixes: 1ad0de78e794 ("media: v4l: Add HDR10 static metadata controls") Cc: stable@vger.kernel.org Signed-off-by: Ming Qian Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

crypto: qat - remove unused character device and IOCTLs

2026-07-04T11:39:41+00:00

[ Upstream commit d237230728c567297f2f98b425d63156ab2ed17f ] The QAT driver exposes a character device (qat_adf_ctl) with IOCTLs for device configuration, start, stop, status query and enumeration. These IOCTLs are not part of any public uAPI header and have no known in-tree or out-of-tree users. Device lifecycle is already managed via sysfs. The ioctl interface also increases the attack surface and is the subject of a number of bug reports. Remove the character device, the IOCTL definitions, and the related data structures (adf_dev_status_info, adf_user_cfg_key_val, adf_user_cfg_section, adf_user_cfg_ctl_data). Drop the now-unused adf_cfg_user.h header and strip adf_ctl_drv.c down to the minimal module_init/module_exit hooks for workqueue, AER, and crypto/compression algorithm registration. Clean up leftover dead code that was only reachable from the removed IOCTL paths: adf_cfg_del_all(), adf_devmgr_verify_id(), adf_devmgr_get_num_dev(), adf_devmgr_get_dev_by_id(), adf_get_vf_real_id() and the unused ADF_CFG macros. Additionally, drop the entry associated to QAT IOCTLs in ioctl-number.rst. Cc: stable@vger.kernel.org Fixes: d8cba25d2c68 ("crypto: qat - Intel(R) QAT driver framework") Reported-by: Zhi Wang Reported-by: Bin Yu Reported-by: MingYu Wang Closes: https://lore.kernel.org/all/61d6d499.ab89.19b9b7f3186.Coremail.wangzhi_xd@stu.xidian.edu.cn/ Link: https://lore.kernel.org/all/20260508034841.256794-1-w15303746062@163.com/ Link: https://lore.kernel.org/all/20260508023542.256299-1-w15303746062@163.com/ Link: https://lore.kernel.org/all/20260504025120.98242-1-w15303746062@163.com/ Signed-off-by: Giovanni Cabiddu Reviewed-by: Ahsan Atta Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Documentation: ioctl-number: Extend "Include File" column width

2026-07-04T11:39:41+00:00

[ Upstream commit 15afd5def819e4df2a29cef6fcfa6ae7ba167c0f ] Extend width of "Include File" column to fit full path to papr-physical-attestation.h in later commit. Reviewed-by: Haren Myneni Signed-off-by: Bagas Sanjaya Acked-by: Madhavan Srinivasan Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20250714015711.14525-3-bagasdotme@gmail.com Stable-dep-of: d237230728c5 ("crypto: qat - remove unused character device and IOCTLs") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Remove DECnet support from kernel

2023-06-21T13:59:15+00:00

commit 1202cdd665315c525b5237e96e0bedc76d7e754f upstream. DECnet is an obsolete network protocol that receives more attention from kernel janitors than users. It belongs in computer protocol history museum not in Linux kernel. It has been "Orphaned" in kernel since 2010. The iproute2 support for DECnet was dropped in 5.0 release. The documentation link on Sourceforge says it is abandoned there as well. Leave the UAPI alone to keep userspace programs compiling. This means that there is still an empty neighbour table for AF_DECNET. The table of /proc/sys/net entries was updated to match current directories and reformatted to be alphabetical. Signed-off-by: Stephen Hemminger Acked-by: David Ahern Acked-by: Nikolay Aleksandrov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

media: hevc: Embedded indexes in RPS

2022-08-17T12:23:31+00:00

[ Upstream commit d95a63daca85f4bca3b70e622c75586b5bf0ea5c ] Reference Picture Set lists provide indices of short and long term reference in DBP array. Fix Hantro to not do a look up in DBP entries. Make documentation more clear about it. [hverkuil: fix typo in commit log] Signed-off-by: Benjamin Gaignard Reviewed-by: Ezequiel Garcia Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin

landlock: Reduce the maximum number of layers to 16

2022-06-09T08:23:24+00:00

commit 75c542d6c6cc48720376862d5496d51509160dfd upstream. The maximum number of nested Landlock domains is currently 64. Because of the following fix and to help reduce the stack size, let's reduce it to 16. This seems large enough for a lot of use cases (e.g. sandboxed init service, spawning a sandboxed SSH service, in nested sandboxed containers). Reducing the number of nested domains may also help to discover misuse of Landlock (e.g. creating a domain per rule). Add and use a dedicated layer_mask_t typedef to fit with the number of layers. This might be useful when changing it and to keep it consistent with the maximum number of layers. Reviewed-by: Paul Moore Link: https://lore.kernel.org/r/20220506161102.525323-3-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün Signed-off-by: Greg Kroah-Hartman

ptp: Document the PTP_CLK_MAGIC ioctl number

2021-10-28T00:02:51+00:00

Add PTP_CLK_MAGIC to the userspace-api/ioctl/ioctl-number.rst documentation file. Fixes: d94ba80ebbea ("ptp: Added a brand new class driver for ptp clocks.") Signed-off-by: Randy Dunlap Cc: Richard Cochran Cc: John Stultz Cc: Jonathan Corbet Link: https://lore.kernel.org/r/20211024163831.10200-1-rdunlap@infradead.org Signed-off-by: Jakub Kicinski

VDUSE: fix documentation underline warning

2021-10-13T12:42:07+00:00

Fix a VDUSE documentation build warning: Documentation/userspace-api/vduse.rst:21: WARNING: Title underline too short. Fixes: 7bc7f61897b6 ("Documentation: Add documentation for VDUSE") Signed-off-by: Randy Dunlap Cc: Xie Yongji Cc: Jason Wang Cc: Michael S. Tsirkin Cc: virtualization@lists.linux-foundation.org Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20211006202904.30241-1-rdunlap@infradead.org Signed-off-by: Michael S. Tsirkin Reviewed-by: Xie Yongji Acked-by: Jason Wang

Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

2021-09-11T21:48:42+00:00

Pull virtio updates from Michael Tsirkin: - vduse driver ("vDPA Device in Userspace") supporting emulated virtio block devices - virtio-vsock support for end of record with SEQPACKET - vdpa: mac and mq support for ifcvf and mlx5 - vdpa: management netlink for ifcvf - virtio-i2c, gpio dt bindings - misc fixes and cleanups * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (39 commits) Documentation: Add documentation for VDUSE vduse: Introduce VDUSE - vDPA Device in Userspace vduse: Implement an MMU-based software IOTLB vdpa: Support transferring virtual addressing during DMA mapping vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap() vdpa: Add an opaque pointer for vdpa_config_ops.dma_map() vhost-iotlb: Add an opaque pointer for vhost IOTLB vhost-vdpa: Handle the failure of vdpa_reset() vdpa: Add reset callback in vdpa_config_ops vdpa: Fix some coding style issues file: Export receive_fd() to modules eventfd: Export eventfd_wake_count to modules iova: Export alloc_iova_fast() and free_iova_fast() virtio-blk: remove unneeded "likely" statements virtio-balloon: Use virtio_find_vqs() helper vdpa: Make use of PFN_PHYS/PFN_UP/PFN_DOWN helper macro vsock_test: update message bounds test for MSG_EOR af_vsock: rename variables in receive loop virtio/vsock: support MSG_EOR bit processing vhost/vsock: support MSG_EOR bit processing ...

Documentation: Add documentation for VDUSE

2021-09-06T11:20:58+00:00

VDUSE (vDPA Device in Userspace) is a framework to support implementing software-emulated vDPA devices in userspace. This document is intended to clarify the VDUSE design and usage. Signed-off-by: Xie Yongji Acked-by: Jason Wang Link: https://lore.kernel.org/r/20210831103634.33-14-xieyongji@bytedance.com Signed-off-by: Michael S. Tsirkin