linux/kernel/cgroup, branch v6.14

Merge tag 'drm-misc-fixes-2025-02-20' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes

2025-02-20T23:16:35Z

An reset signal polarity fix for the jd9365da-h3 panel, a folio handling fix and config fix in nouveau, a dmem cgroup descendant pool handling fix, and a missing header for amdxdna. Signed-off-by: Dave Airlie From: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20250220-glorious-cockle-of-might-5b35f7@houat

cgroup/dmem: Don't open-code css_for_each_descendant_pre

2025-02-19T08:50:37Z

The current implementation has a bug: If the current css doesn't contain any pool that is a descendant of the "pool" (i.e. when found_descendant == false), then "pool" will point to some unrelated pool. If the current css has a child, we'll overwrite parent_pool with this unrelated pool on the next iteration. Since we can just check whether a pool refers to the same region to determine whether or not it's related, all the additional pool tracking is unnecessary, so just switch to using css_for_each_descendant_pre for traversal. Fixes: b168ed458dde ("kernel/cgroup: Add "dmem" memory accounting cgroup") Signed-off-by: Friedrich Vock Reviewed-by: Maarten Lankhorst Link: https://patchwork.freedesktop.org/patch/msgid/20250127152754.21325-1-friedrich.vock@gmx.de Signed-off-by: Maarten Lankhorst

cgroup: Remove steal time from usage_usec

2025-02-07T21:02:17Z

The CPU usage time is the time when user, system or both are using the CPU. Steal time is the time when CPU is waiting to be run by the Hypervisor. It should not be added to the CPU usage time, hence removing it from the usage_usec entry. Fixes: 936f2a70f2077 ("cgroup: add cpu.stat file to root cgroup") Acked-by: Axel Busch Acked-by: Michal Koutný Signed-off-by: Muhammad Adeel Signed-off-by: Tejun Heo

cgroup: fix race between fork and cgroup.kill

2025-02-02T16:54:51Z

Tejun reported the following race between fork() and cgroup.kill at [1]. Tejun: I was looking at cgroup.kill implementation and wondering whether there could be a race window. So, __cgroup_kill() does the following: k1. Set CGRP_KILL. k2. Iterate tasks and deliver SIGKILL. k3. Clear CGRP_KILL. The copy_process() does the following: c1. Copy a bunch of stuff. c2. Grab siglock. c3. Check fatal_signal_pending(). c4. Commit to forking. c5. Release siglock. c6. Call cgroup_post_fork() which puts the task on the css_set and tests CGRP_KILL. The intention seems to be that either a forking task gets SIGKILL and terminates on c3 or it sees CGRP_KILL on c6 and kills the child. However, I don't see what guarantees that k3 can't happen before c6. ie. After a forking task passes c5, k2 can take place and then before the forking task reaches c6, k3 can happen. Then, nobody would send SIGKILL to the child. What am I missing? This is indeed a race. One way to fix this race is by taking cgroup_threadgroup_rwsem in write mode in __cgroup_kill() as the fork() side takes cgroup_threadgroup_rwsem in read mode from cgroup_can_fork() to cgroup_post_fork(). However that would be heavy handed as this adds one more potential stall scenario for cgroup.kill which is usually called under extreme situation like memory pressure. To fix this race, let's maintain a sequence number per cgroup which gets incremented on __cgroup_kill() call. On the fork() side, the cgroup_can_fork() will cache the sequence number locally and recheck it against the cgroup's sequence number at cgroup_post_fork() site. If the sequence numbers mismatch, it means __cgroup_kill() can been called and we should send SIGKILL to the newly created task. Reported-by: Tejun Heo Closes: https://lore.kernel.org/all/Z5QHE2Qn-QZ6M-KW@slm.duckdns.org/ [1] Fixes: 661ee6280931 ("cgroup: introduce cgroup.kill") Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Shakeel Butt Reviewed-by: Michal Koutný Signed-off-by: Tejun Heo

Merge v6.13 into drm-next

2025-01-23T13:42:21Z

A regression was caused by commit e4b5ccd392b9 ("drm/v3d: Ensure job pointer is set to NULL after job completion"), but this commit is not yet in next-fixes, fast-forward it. Note that this recreates Linus merge in 96c84703f1cf ("Merge tag 'drm-next-2025-01-17' of https://gitlab.freedesktop.org/drm/kernel") because I didn't want to backmerge a random point in the merge window. Signed-off-by: Simona Vetter

Merge tag 'drm-next-2025-01-17' of https://gitlab.freedesktop.org/drm/kernel

2025-01-22T00:09:47Z

Pull drm updates from Dave Airlie: "There are two external interactions of note, the msm tree pull in some opp tree, hopefully the opp tree arrives from the same git tree however it normally does. There is also a new cgroup controller for device memory, that is used by drm, so is merging through my tree. This will hopefully help open up gpu cgroup usage a bit more and move us forward. There is a new accelerator driver for the AMD XDNA Ryzen AI NPUs. Then the usual xe/amdgpu/i915/msm leaders and lots of changes and refactors across the board: core: - device memory cgroup controller added - Remove driver date from drm_driver - Add drm_printer based hex dumper - drm memory stats docs update - scheduler documentation improvements new driver: - amdxdna - Ryzen AI NPU support connector: - add a mutex to protect ELD - make connector setup two-step panels: - Introduce backlight quirks infrastructure - New panels: KDB KD116N2130B12, Tianma TM070JDHG34-00, - Multi-Inno Technology MI1010Z1T-1CP11 bridge: - ti-sn65dsi83: Add ti,lvds-vod-swing optional properties - Provide default implementation of atomic_check for HDMI bridges - it605: HDCP improvements, MCCS Support xe: - make OA buffer size configurable - GuC capture fixes - add ufence and g2h flushes - restore system memory GGTT mappings - ioctl fixes - SRIOV PF scheduling priority - allow fault injection - lots of improvements/refactors - Enable GuC's WA_DUAL_QUEUE for newer platforms - IRQ related fixes and improvements i915: - More accurate engine busyness metrics with GuC submission - Ensure partial BO segment offset never exceeds allowed max - Flush GuC CT receive tasklet during reset preparation - Some DG2 refactor to fix DG2 bugs when operating with certain CPUs - Fix DG1 power gate sequence - Enabling uncompressed 128b/132b UHBR SST - Handle hdmi connector init failures, and no HDMI/DP cases - More robust engine resets on Haswell and older i915/xe display: - HDCP fixes for Xe3Lpd - New GSC FW ARL-H/ARL-U - support 3 VDSC engines 12 slices - MBUS joining sanitisation - reconcile i915/xe display power mgmt - Xe3Lpd fixes - UHBR rates for Thunderbolt amdgpu: - DRM panic support - track BO memory stats at runtime - Fix max surface handling in DC - Cleaner shader support for gfx10.3 dGPUs - fix drm buddy trim handling - SDMA engine reset updates - Fix doorbell ttm cleanup - RAS updates - ISP updates - SDMA queue reset support - Rework DPM powergating interfaces - Documentation updates and cleanups - DCN 3.5 updates - Use a pm notifier to more gracefully handle VRAM eviction on suspend or hibernate - Add debugfs interfaces for forcing scheduling to specific engine instances - GG 9.5 updates - IH 4.4 updates - Make missing optional firmware less noisy - PSP 13.x updates - SMU 13.x updates - VCN 5.x updates - JPEG 5.x updates - GC 12.x updates - DC FAMS updates amdkfd: - GG 9.5 updates - Logging improvements - Shader debugger fixes - Trap handler cleanup - Cleanup includes - Eviction fence wq fix msm: - MDSS: - properly described UBWC registers - added SM6150 (aka QCS615) support - DPU: - added SM6150 (aka QCS615) support - enabled wide planes if virtual planes are enabled (by using two SSPPs for a single plane) - added CWB hardware blocks support - DSI: - added SM6150 (aka QCS615) support - GPU: - Print GMU core fw version - GMU bandwidth voting for a740 and a750 - Expose uche trap base via uapi - UAPI error reporting rcar-du: - Add r8a779h0 Support ivpu: - Fix qemu crash when using passthrough nouveau: - expose GSP-RM logging buffers via debugfs panfrost: - Add MT8188 Mali-G57 MC3 support rockchip: - Gamma LUT support hisilicon: - new HIBMC support virtio-gpu: - convert to helpers - add prime support for scanout buffers v3d: - Add DRM_IOCTL_V3D_PERFMON_SET_GLOBAL vc4: - Add support for BCM2712 vkms: - line-per-line compositing algorithm to improve performance zynqmp: - Add DP audio support mediatek: - dp: Add sdp path reset - dp: Support flexible length of DP calibration data etnaviv: - add fdinfo memory support - add explicit reset handling" * tag 'drm-next-2025-01-17' of https://gitlab.freedesktop.org/drm/kernel: (1070 commits) drm/bridge: fix documentation for the hdmi_audio_prepare() callback doc/cgroup: Fix title underline length drm/doc: Include new drm-compute documentation cgroup/dmem: Fix parameters documentation cgroup/dmem: Select PAGE_COUNTER kernel/cgroup: Remove the unused variable climit drm/display: hdmi: Do not read EDID on disconnected connectors drm/tests: hdmi: Add connector disablement test drm/connector: hdmi: Do atomic check when necessary drm/amd/display: 3.2.316 drm/amd/display: avoid reset DTBCLK at clock init drm/amd/display: improve dpia pre-train drm/amd/display: Apply DML21 Patches drm/amd/display: Use HW lock mgr for PSR1 drm/amd/display: Revised for Replay Pseudo vblank control drm/amd/display: Add a new flag for replay low hz drm/amd/display: Remove unused read_ono_state function from Hwss module drm/amd/display: Do not elevate mem_type change to full update drm/amd/display: Do not wait for PSR disable on vbl enable drm/amd/display: Remove unnecessary eDP power down ...

cgroup/dmem: Fix parameters documentation

2025-01-15T08:45:24Z

During the dmem cgroup development, the parameters to the dmem_cgroup_state_evict_valuable() and dmem_cgroup_try_charge() were changed, but the documentation wasn't adjusted accordingly. This results in a documentation build warning. Adjust the documentation to reflect what the final functions parameters are. Fixes: b168ed458dde ("kernel/cgroup: Add "dmem" memory accounting cgroup") Reported-by: Stephen Rothwell Closes: https://lore.kernel.org/r/20250113160334.1f09f881@canb.auug.org.au/ Acked-by: Tejun Heo Reviewed-by: Simona Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20250113092608.1349287-2-mripard@kernel.org Signed-off-by: Maxime Ripard

kernel/cgroup: Remove the unused variable climit

2025-01-15T08:39:26Z

Variable climit is not effectively used, so delete it. kernel/cgroup/dmem.c:302:23: warning: variable ‘climit’ set but not used. Reported-by: Abaci Robot Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=13512 Signed-off-by: Jiapeng Chong Acked-by: Tejun Heo Link: https://patchwork.freedesktop.org/patch/msgid/20250114062804.5092-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Maxime Ripard

cgroup/cpuset: remove kernfs active break

2025-01-09T01:54:39Z

A warning was found: WARNING: CPU: 10 PID: 3486953 at fs/kernfs/file.c:828 CPU: 10 PID: 3486953 Comm: rmdir Kdump: loaded Tainted: G RIP: 0010:kernfs_should_drain_open_files+0x1a1/0x1b0 RSP: 0018:ffff8881107ef9e0 EFLAGS: 00010202 RAX: 0000000080000002 RBX: ffff888154738c00 RCX: dffffc0000000000 RDX: 0000000000000007 RSI: 0000000000000004 RDI: ffff888154738c04 RBP: ffff888154738c04 R08: ffffffffaf27fa15 R09: ffffed102a8e7180 R10: ffff888154738c07 R11: 0000000000000000 R12: ffff888154738c08 R13: ffff888750f8c000 R14: ffff888750f8c0e8 R15: ffff888154738ca0 FS: 00007f84cd0be740(0000) GS:ffff8887ddc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555f9fbe00c8 CR3: 0000000153eec001 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kernfs_drain+0x15e/0x2f0 __kernfs_remove+0x165/0x300 kernfs_remove_by_name_ns+0x7b/0xc0 cgroup_rm_file+0x154/0x1c0 cgroup_addrm_files+0x1c2/0x1f0 css_clear_dir+0x77/0x110 kill_css+0x4c/0x1b0 cgroup_destroy_locked+0x194/0x380 cgroup_rmdir+0x2a/0x140 It can be explained by: rmdir echo 1 > cpuset.cpus kernfs_fop_write_iter // active=0 cgroup_rm_file kernfs_remove_by_name_ns kernfs_get_active // active=1 __kernfs_remove // active=0x80000002 kernfs_drain cpuset_write_resmask wait_event //waiting (active == 0x80000001) kernfs_break_active_protection // active = 0x80000001 // continue kernfs_unbreak_active_protection // active = 0x80000002 ... kernfs_should_drain_open_files // warning occurs kernfs_put_active This warning is caused by 'kernfs_break_active_protection' when it is writing to cpuset.cpus, and the cgroup is removed concurrently. The commit 3a5a6d0c2b03 ("cpuset: don't nest cgroup_mutex inside get_online_cpus()") made cpuset_hotplug_workfn asynchronous, This change involves calling flush_work(), which can create a multiple processes circular locking dependency that involve cgroup_mutex, potentially leading to a deadlock. To avoid deadlock. the commit 76bb5ab8f6e3 ("cpuset: break kernfs active protection in cpuset_write_resmask()") added 'kernfs_break_active_protection' in the cpuset_write_resmask. This could lead to this warning. After the commit 2125c0034c5d ("cgroup/cpuset: Make cpuset hotplug processing synchronous"), the cpuset_write_resmask no longer needs to wait the hotplug to finish, which means that concurrent hotplug and cpuset operations are no longer possible. Therefore, the deadlock doesn't exist anymore and it does not have to 'break active protection' now. To fix this warning, just remove kernfs_break_active_protection operation in the 'cpuset_write_resmask'. Fixes: bdb2fd7fc56e ("kernfs: Skip kernfs_drain_open_files() more aggressively") Fixes: 76bb5ab8f6e3 ("cpuset: break kernfs active protection in cpuset_write_resmask()") Reported-by: Ji Fa Signed-off-by: Chen Ridong Acked-by: Waiman Long Signed-off-by: Tejun Heo

kernel/cgroup: Add "dmem" memory accounting cgroup

2025-01-06T16:24:38Z

This code is based on the RDMA and misc cgroup initially, but now uses page_counter. It uses the same min/low/max semantics as the memory cgroup as a result. There's a small mismatch as TTM uses u64, and page_counter long pages. In practice it's not a problem. 32-bits systems don't really come with >=4GB cards and as long as we're consistently wrong with units, it's fine. The device page size may not be in the same units as kernel page size, and each region might also have a different page size (VRAM vs GART for example). The interface is simple: - Call dmem_cgroup_register_region() - Use dmem_cgroup_try_charge to check if you can allocate a chunk of memory, use dmem_cgroup__uncharge when freeing it. This may return an error code, or -EAGAIN when the cgroup limit is reached. In that case a reference to the limiting pool is returned. - The limiting cs can be used as compare function for dmem_cgroup_state_evict_valuable. - After having evicted enough, drop reference to limiting cs with dmem_cgroup_pool_state_put. This API allows you to limit device resources with cgroups. You can see the supported cards in /sys/fs/cgroup/dmem.capacity You need to echo +dmem to cgroup.subtree_control, and then you can partition device memory. Co-developed-by: Friedrich Vock Signed-off-by: Friedrich Vock Co-developed-by: Maxime Ripard Signed-off-by: Maarten Lankhorst Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20241204143112.1250983-1-dev@lankhorst.se Signed-off-by: Maxime Ripard