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2025-07-28Merge tag 'pm-6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "As is tradition, cpufreq is the part with the largest number of updates that include core fixes and cleanups as well as updates of several assorted drivers, but there are also quite a few updates related to system sleep, mostly focused on asynchronous suspend and resume of devices and on making the integration of system suspend and resume with runtime PM easier. Runtime PM is also updated to allow some code duplication in drivers to be eliminated going forward and to work more consistently overall in some cases. Apart from that, there are some driver core updates related to PM domains that should help to address ordering issues with devm_ cleanup routines relying on PM domains, some assorted devfreq updates including core fixes and cleanups, tooling updates, and documentation and MAINTAINERS updates. Specifics: - Fix two initialization ordering issues in the cpufreq core and a governor initialization error path in it, and clean it up (Lifeng Zheng) - Add Granite Rapids support in no-HWP mode to the intel_pstate cpufreq driver (Li RongQing) - Make intel_pstate always use HWP_DESIRED_PERF when operating in the passive mode (Rafael Wysocki) - Allow building the tegra124 cpufreq driver as a module (Aaron Kling) - Do minor cleanups for Rust cpufreq and cpumask APIs and fix MAINTAINERS entry for cpu.rs (Abhinav Ananthu, Ritvik Gupta, Lukas Bulwahn) - Clean up assorted cpufreq drivers (Arnd Bergmann, Dan Carpenter, Krzysztof Kozlowski, Sven Peter, Svyatoslav Ryhel, Lifeng Zheng) - Add the NEED_UPDATE_LIMITS flag to the CPPC cpufreq driver (Prashant Malani) - Fix minimum performance state label error in the amd-pstate driver documentation (Shouye Liu) - Add the CPUFREQ_GOV_STRICT_TARGET flag to the userspace cpufreq governor and explain HW coordination influence on it in the documentation (Shashank Balaji) - Fix opencoded for_each_cpu() in idle_state_valid() in the DT cpuidle driver (Yury Norov) - Remove info about non-existing QoS interfaces from the PM QoS documentation (Ulf Hansson) - Use c_* types via kernel prelude in Rust for OPP (Abhinav Ananthu) - Add HiSilicon uncore frequency scaling driver to devfreq (Jie Zhan) - Allow devfreq drivers to add custom sysfs ABIs (Jie Zhan) - Simplify the sun8i-a33-mbus devfreq driver by using more devm functions (Uwe Kleine-König) - Fix an index typo in trans_stat() in devfreq (Chanwoo Choi) - Check devfreq governor before using governor->name (Lifeng Zheng) - Remove a redundant devfreq_get_freq_range() call from devfreq_add_device() (Lifeng Zheng) - Limit max_freq with scaling_min_freq in devfreq (Lifeng Zheng) - Replace sscanf() with kstrtoul() in set_freq_store() (Lifeng Zheng) - Extend the asynchronous suspend and resume of devices to handle suppliers like parents and consumers like children (Rafael Wysocki) - Make pm_runtime_force_resume() work for drivers that set the DPM_FLAG_SMART_SUSPEND flag and allow PCI drivers and drivers that collaborate with the general ACPI PM domain to set it (Rafael Wysocki) - Add kernel parameter to disable asynchronous suspend/resume of devices (Tudor Ambarus) - Drop redundant might_sleep() calls from some functions in the device suspend/resume core code (Zhongqiu Han) - Fix the handling of monitors connected right before waking up the system from sleep (tuhaowen) - Clean up MAINTAINERS entries for suspend and hibernation (Rafael Wysocki) - Fix error code path in the KEXEC_JUMP flow and drop a redundant pm_restore_gfp_mask() call from it (Rafael Wysocki) - Rearrange suspend/resume error handling in the core device suspend and resume code (Rafael Wysocki) - Fix up white space that does not follow coding style in the hibernation core code (Darshan Rathod) - Document return values of suspend-related API functions in the runtime PM framework (Sakari Ailus) - Mark last busy stamp in multiple autosuspend-related functions in the runtime PM framework and update its documentation (Sakari Ailus) - Take active children into account in pm_runtime_get_if_in_use() for consistency (Rafael Wysocki) - Fix NULL pointer dereference in get_pd_power_uw() in the dtpm_cpu power capping driver (Sivan Zohar-Kotzer) - Add support for the Bartlett Lake platform to the Intel RAPL power capping driver (Qiao Wei) - Add PL4 support for Panther Lake to the intel_rapl_msr power capping driver (Zhang Rui) - Update contact information in the PM ABI docs and maintainer information in the power domains DT binding (Rafael Wysocki) - Update PM header inclusions to follow the IWYU (Include What You Use) principle (Andy Shevchenko) - Add flags to specify power on attach/detach for PM domains, make the driver core detach PM domains in device_unbind_cleanup(), and drop the dev_pm_domain_detach() call from the platform bus type (Claudiu Beznea) - Improve Python binding's Makefile for cpupower (John B. Wyatt IV) - Fix printing of CORE, CPU fields in cpupower-monitor (Gautham Shenoy)" * tag 'pm-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits) cpufreq: CPPC: Mark driver with NEED_UPDATE_LIMITS flag PM: docs: Use my kernel.org address in ABI docs and DT bindings PM: hibernate: Fix up white space that does not follow coding style PM: sleep: Rearrange suspend/resume error handling in the core Documentation: amd-pstate:fix minimum performance state label error PM: runtime: Take active children into account in pm_runtime_get_if_in_use() kexec_core: Drop redundant pm_restore_gfp_mask() call kexec_core: Fix error code path in the KEXEC_JUMP flow PM: sleep: Clean up MAINTAINERS entries for suspend and hibernation drivers: cpufreq: add Tegra114 support rust: cpumask: Replace `MaybeUninit` and `mem::zeroed` with `Opaque` APIs cpufreq: Exit governor when failed to start old governor cpufreq: Move the check of cpufreq_driver->get into cpufreq_verify_current_freq() cpufreq: Init policy->rwsem before it may be possibly used cpufreq: Initialize cpufreq-based frequency-invariance later cpufreq: Remove duplicate check in __cpufreq_offline() cpufreq: Contain scaling_cur_freq.attr in cpufreq_attrs cpufreq: intel_pstate: Add Granite Rapids support in no-HWP mode cpufreq: intel_pstate: Always use HWP_DESIRED_PERF in passive mode PM / devfreq: Add HiSilicon uncore frequency scaling driver ...
2025-07-28Merge tag 'selinux-pr-20250725' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: - Introduce the concept of a SELinux "neveraudit" type which prevents all auditing of the given type/domain. Taken by itself, the benefit of marking a SELinux domain with the "neveraudit" tag is likely not very interesting, especially given the significant overlap with the "dontaudit" tag. However, given that the "neveraudit" tag applies to *all* auditing of the tagged domain, we can do some fairly interesting optimizations when a SELinux domain is marked as both "permissive" and "dontaudit" (think of the unconfined_t domain). While this pull request includes optimized inode permission and getattr hooks, these optimizations require SELinux policy changes, therefore the improvements may not be visible on standard downstream Linux distos for a period of time. - Continue the deprecation process of /sys/fs/selinux/user. After removing the associated userspace code in 2020, we marked the /sys/fs/selinux/user interface as deprecated in Linux v6.13 with pr_warn() and the usual documention update. This adds a five second sleep after the pr_warn(), following a previous deprecation process pattern that has worked well for us in the past in helping identify any existing users that we haven't yet reached. - Add a __GFP_NOWARN flag to our initial hash table allocation. Fuzzers such a syzbot often attempt abnormally large SELinux policy loads, which the SELinux code gracefully handles by checking for allocation failures, but not before the allocator emits a warning which causes the automated fuzzing to flag this as an error and report it to the list. While we want to continue to support the work done by the fuzzing teams, we want to focus on proper issues and not an error case that is already handled safely. Add a NOWARN flag to quiet the allocator and prevent syzbot from tripping on this again. - Remove some unnecessary selinuxfs cleanup code, courtesy of Al. - Update the SELinux in-kernel documentation with pointers to additional information. * tag 'selinux-pr-20250725' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: don't bother with selinuxfs_info_free() on failures selinux: add __GFP_NOWARN to hashtab_init() allocations selinux: optimize selinux_inode_getattr/permission() based on neveraudit|permissive selinux: introduce neveraudit types documentation: add links to SELinux resources selinux: add a 5 second sleep to /sys/fs/selinux/user
2025-07-28Merge tag 'tpmdd-next-6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd Pull tpm updates from Jarkko Sakkinen: "Quite a few commits but nothing really that would be worth of spending too much time for, or would want to emphasize in particular" * tag 'tpmdd-next-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd: tpm_crb_ffa: handle tpm busy return code tpm_crb_ffa: Remove memset usage tpm_crb_ffa: Fix typos in function name tpm: Check for completion after timeout tpm: Use of_reserved_mem_region_to_resource() for "memory-region" tpm: Replace scnprintf() with sysfs_emit() and sysfs_emit_at() in sysfs show functions tpm_crb_ffa: Remove unused export tpm: tpm_crb_ffa: try to probe tpm_crb_ffa when it's built-in firmware: arm_ffa: Change initcall level of ffa_init() to rootfs_initcall tpm/tpm_svsm: support TPM_CHIP_FLAG_SYNC tpm/tpm_ftpm_tee: support TPM_CHIP_FLAG_SYNC tpm: support devices with synchronous send() tpm: add bufsiz parameter in the .send callback
2025-07-28Merge tag 'hardening-v6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - Introduce and start using TRAILING_OVERLAP() helper for fixing embedded flex array instances (Gustavo A. R. Silva) - mux: Convert mux_control_ops to a flex array member in mux_chip (Thorsten Blum) - string: Group str_has_prefix() and strstarts() (Andy Shevchenko) - Remove KCOV instrumentation from __init and __head (Ritesh Harjani, Kees Cook) - Refactor and rename stackleak feature to support Clang - Add KUnit test for seq_buf API - Fix KUnit fortify test under LTO * tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits) sched/task_stack: Add missing const qualifier to end_of_stack() kstack_erase: Support Clang stack depth tracking kstack_erase: Add -mgeneral-regs-only to silence Clang warnings init.h: Disable sanitizer coverage for __init and __head kstack_erase: Disable kstack_erase for all of arm compressed boot code x86: Handle KCOV __init vs inline mismatches arm64: Handle KCOV __init vs inline mismatches s390: Handle KCOV __init vs inline mismatches arm: Handle KCOV __init vs inline mismatches mips: Handle KCOV __init vs inline mismatch powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON configs/hardening: Enable CONFIG_KSTACK_ERASE stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth stackleak: Rename STACKLEAK to KSTACK_ERASE seq_buf: Introduce KUnit tests string: Group str_has_prefix() and strstarts() kunit/fortify: Add back "volatile" for sizeof() constants acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings ...
2025-07-24docs: update THP documentation to clarify sysfs "never" settingLorenzo Stoakes
Rather confusingly, setting all Transparent Huge Page sysfs settings to "never" does not in fact result in THP being globally disabled. Rather, it results in khugepaged being disabled, but one can still obtain THP pages using madvise(..., MADV_COLLAPSE). This is something that has remained poorly documented for some time, and it is likely the received wisdom of most users of THP that never does, in fact, mean never. It is therefore important to highlight, very clearly, that this is not the case. [lorenzo.stoakes@oracle.com: update transhuge page to mention MADV_COLLAPSE] Link: https://lkml.kernel.org/r/d54d1dfb-f06d-4979-983b-73998f05867e@lucifer.local Link: https://lkml.kernel.org/r/20250721155530.75944-1-lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: SeongJae Park <sj@kernel.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Barry Song <baohua@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mariano Pache <npache@redhat.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-24Docs/admin-guide/mm/damon/usage: document refresh_ms fileSeongJae Park
Document the new DAMON sysfs file, refresh_ms, on the usage document. Link: https://lkml.kernel.org/r/20250717055448.56976-4-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-23docs: Downgrade arm64 & riscv from titles to commentJoel Granados
Remove the title string ("====") from under arm64 & riscv and move them to a commment under the perf_user_access sysctl. They are explanations, *not* sysctls themselves This effectively removes these two strings from appearing as not implemented when the check-sysctl-docs script is run Signed-off-by: Joel Granados <joel.granados@kernel.org>
2025-07-23docs: Remove colon from ctltable title in vm.rstJoel Granados
Removing them solves an issue where they were incorrectly considered as not implemented by the check-sysctl-docs script Signed-off-by: Joel Granados <joel.granados@kernel.org>
2025-07-23tpm_crb_ffa: handle tpm busy return codePrachotan Bathi
Platforms supporting direct message request v2 [1] can support secure partitions that support multiple services. For CRB over FF-A interface, if the firmware TPM or TPM service [1] shares its Secure Partition (SP) with another service, message requests may fail with a -EBUSY error. To handle this, replace the single check and call with a retry loop that attempts the TPM message send operation until it succeeds or a configurable timeout is reached. Implement a _try_send_receive function to do a single send/receive and modify the existing send_receive to add this retry loop. The retry mechanism introduces a module parameter (`busy_timeout_ms`, default: 2000ms) to control how long to keep retrying on -EBUSY responses. Between retries, the code waits briefly (50-100 microseconds) to avoid busy-waiting and handling TPM BUSY conditions more gracefully. The parameter can be modified at run-time as such: echo 3000 | tee /sys/module/tpm_crb_ffa/parameters/busy_timeout_ms This changes the timeout from the default 2000ms to 3000ms. [1] TPM Service Command Response Buffer Interface Over FF-A https://developer.arm.com/documentation/den0138/latest/ Signed-off-by: Prachotan Bathi <prachotan.bathi@arm.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2025-07-22Merge branch 'pm-sleep'Rafael J. Wysocki
Merge updates related to system sleep for 6.17-rc1: - Extend the asynchronous suspend and resume of devices to handle suppliers like parents and consumers like children (Rafael Wysocki) - Make pm_runtime_force_resume() work for drivers that set the DPM_FLAG_SMART_SUSPEND flag and allow PCI drivers and drivers that collaborate with the general ACPI PM domain to set it (Rafael Wysocki) - Add kernel parameter to disable asynchronous suspend/resume of devices (Tudor Ambarus) - Drop redundant might_sleep() calls from some functions in the device suspend/resume core code (Zhongqiu Han) - Fix the handling of monitors connected right before waking up the system from sleep (tuhaowen) - Clean up MAINTAINERS entries for suspend and hibernation (Rafael Wysocki) - Fix error code path in the KEXEC_JUMP flow and drop a redundant pm_restore_gfp_mask() call from it (Rafael Wysocki) - Rearrange suspend/resume error handling in the core device suspend and resume code (Rafael Wysocki) - Fix up white space that does not follow coding style in the hibernation core code (Darshan Rathod) * pm-sleep: PM: hibernate: Fix up white space that does not follow coding style PM: sleep: Rearrange suspend/resume error handling in the core kexec_core: Drop redundant pm_restore_gfp_mask() call kexec_core: Fix error code path in the KEXEC_JUMP flow PM: sleep: Clean up MAINTAINERS entries for suspend and hibernation PM: sleep: add kernel parameter to disable asynchronous suspend/resume PCI/PM: Set power.strict_midlayer in pci_pm_init() ACPI: PM: Set/clear power.strict_midlayer in prepare/complete PM: sleep: Add strict_midlayer flag to struct dev_pm_info PM: runtime: Introduce __rpm_get_driver_callback() PM: Check power.needs_force_resume in pm_runtime_force_suspend() PM: runtime: Clear power.needs_force_resume in pm_runtime_reinit() PM: Make pm_runtime_force_resume() work with DPM_FLAG_SMART_SUSPEND PM: Move two sleep-related functions under CONFIG_PM_SLEEP PM: Use true/false as power.needs_force_resume values PM: sleep: Make async suspend handle suppliers like parents PM: sleep: Make async resume handle consumers like children PM: sleep: Drop superfluous might_sleep() calls PM: sleep: console: Fix the black screen issue
2025-07-21stackleak: Rename STACKLEAK to KSTACK_ERASEKees Cook
In preparation for adding Clang sanitizer coverage stack depth tracking that can support stack depth callbacks: - Add the new top-level CONFIG_KSTACK_ERASE option which will be implemented either with the stackleak GCC plugin, or with the Clang stack depth callback support. - Rename CONFIG_GCC_PLUGIN_STACKLEAK as needed to CONFIG_KSTACK_ERASE, but keep it for anything specific to the GCC plugin itself. - Rename all exposed "STACKLEAK" names and files to "KSTACK_ERASE" (named for what it does rather than what it protects against), but leave as many of the internals alone as possible to avoid even more churn. While here, also split "prev_lowest_stack" into CONFIG_KSTACK_ERASE_METRICS, since that's the only place it is referenced from. Suggested-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250717232519.2984886-1-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>
2025-07-19panic: add note that panic_print sysctl interface is deprecatedFeng Tang
Add a dedicated core parameter 'panic_console_replay' for controlling console replay, and add note that 'panic_print' sysctl interface will be obsoleted by 'panic_sys_info' and 'panic_console_replay'. When it happens, the SYS_INFO_PANIC_CONSOLE_REPLAY can be removed as well. Link: https://lkml.kernel.org/r/20250703021004.42328-6-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Suggested-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19panic: add 'panic_sys_info=' setup option for kernel cmdlineFeng Tang
'panic_sys_info=' sysctl interface is already added for runtime setting. Add counterpart kernel cmdline option for boottime setting. Link: https://lkml.kernel.org/r/20250703021004.42328-5-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Suggested-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19panic: add 'panic_sys_info' sysctl to take human readable string parameterFeng Tang
Bitmap definition for 'panic_print' is hard to remember and decode. Add 'panic_sys_info='sysctl to take human readable string like "tasks,mem,timers,locks,ftrace,..." and translate it into bitmap. The detailed mapping is: SYS_INFO_TASKS "tasks" SYS_INFO_MEM "mem" SYS_INFO_TIMERS "timers" SYS_INFO_LOCKS "locks" SYS_INFO_FTRACE "ftrace" SYS_INFO_ALL_CPU_BT "all_bt" SYS_INFO_BLOCKED_TASKS "blocked_tasks" [nathan@kernel.org: add __maybe_unused to sys_info_avail] Link: https://lkml.kernel.org/r/20250708-fix-clang-sys_info_avail-warning-v1-1-60d239eacd64@kernel.org Link: https://lkml.kernel.org/r/20250703021004.42328-4-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Suggested-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19panic: clean up code for console replayFeng Tang
Patch series "generalize panic_print's dump function to be used by other kernel parts", v3. When working on kernel stability issues, panic, task-hung and software/hardware lockup are frequently met. And to debug them, user may need lots of system information at that time, like task call stacks, lock info, memory info etc. panic case already has panic_print_sys_info() for this purpose, and has a 'panic_print' bitmask to control what kinds of information is needed, which is also helpful to debug other task-hung and lockup cases. So this patchset extracts the function out to a new file 'lib/sys_info.c', and makes it available for other cases which also need to dump system info for debugging. Also as suggested by Petr Mladek, add 'panic_sys_info=' interface to take human readable string like "tasks,mem,locks,timers,ftrace,....", and eventually obsolete the current 'panic_print' bitmap interface. In RFC and V1 version, hung_task and SW/HW watchdog modules are enabled with the new sys_info dump interface. In v2, they are kept out for better review of current change, and will be posted later. Locally these have been used in our bug chasing for stability issues and was proven helpful. Many thanks to Petr Mladek for great suggestions on both the code and architectures! This patch (of 5): Currently the panic_print_sys_info() was called twice with different parameters to handle console replay case, which is kind of confusing. Add panic_console_replay() explicitly and rename 'PANIC_PRINT_ALL_PRINTK_MSG' to 'PANIC_CONSOLE_REPLAY', to make the code straightforward. The related kernel document is also updated. Link: https://lkml.kernel.org/r/20250703021004.42328-1-feng.tang@linux.alibaba.com Link: https://lkml.kernel.org/r/20250703021004.42328-2-feng.tang@linux.alibaba.com Signed-off-by: Feng Tang <feng.tang@linux.alibaba.com> Suggested-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Lance Yang <lance.yang@linux.dev> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19kdump, documentation: describe craskernel CMA reservationJiri Bohac
Describe the new crashkernel ",cma" suffix in Documentation/ Link: https://lkml.kernel.org/r/aEqpQwUy6gqSiUkV@dwarf.suse.cz Signed-off-by: Jiri Bohac <jbohac@suse.cz> Cc: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Donald Dutile <ddutile@redhat.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Philipp Rudo <prudo@redhat.com> Cc: Pingfan Liu <piliu@redhat.com> Cc: Tao Liu <ltao@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19Docs/admin-guide/mm/damon/usage: document dests directorySeongJae Park
Document the newly added DAMOS action destination directory of the DAMON sysfs interface on the usage document. Link: https://lkml.kernel.org/r/20250709005952.17776-7-bijan311@gmail.com Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Bijan Tabatabai <bijantabatab@micron.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ravi Shankar Jonnalagadda <ravis.opensrc@micron.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-19cgroup: Add compatibility option for content of /proc/cgroupsMichal Koutný
/proc/cgroups lists only v1 controllers by default, however, this is only enforced since the commit af000ce85293b ("cgroup: Do not report unavailable v1 controllers in /proc/cgroups") and there is software in the wild that uses content of /proc/cgroups to decide on availability of v2 (sic) controllers. Add a boottime param that can bring back the previous behavior for setups where the check in the software cannot be changed and it causes e.g. unintended OOMs. Also, this patch takes out cgrp_v1_visible from cgroup1_subsys_absent() guard since it's only important to check which hierarchy (v1 vs v2) the subsys is attached to. This has no effect on the printed message but the code is cleaner since cgrp_v1_visible is really about mounted hierarchies, not the content of /proc/cgroups. Link: https://lore.kernel.org/r/b26b60b7d0d2a5ecfd2f3c45f95f32922ed24686.camel@decadent.org.uk Fixes: af000ce85293b ("cgroup: Do not report unavailable v1 controllers in /proc/cgroups") Fixes: a0ab1453226d8 ("cgroup: Print message when /proc/cgroups is read on v2-only system") Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-07-18irqchip/riscv-imsic: Add kernel parameter to disable IPIsAnup Patel
When injecting IPIs to a set of harts, the IMSIC IPI support will do a separate MMIO write to the SETIPNUM_LE register of each target hart. This means on a platform where IMSIC is trap-n-emulated, there will be N MMIO traps when injecting IPI to N target harts hence IMSIC IPIs will be slow on such platforms compared to the SBI IPI extension. Unfortunately, there is no DT, ACPI, or any other way of discovering whether the underlying IMSIC is trap-n-emulated. Using MMIO write to the SETIPNUM_LE register for injecting IPI is purely a software choice in the IMSIC driver hence add a kernel parameter to allow users to disable IMSIC IPIs on platforms with trap-n-emulated IMSIC. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250716123745.557585-1-apatel@ventanamicro.com
2025-07-17docs: kernel: Clarify printk_ratelimit_burst reset behaviorBreno Leitao
Add clarification that the printk_ratelimit_burst window resets after printk_ratelimit seconds have elapsed, allowing another burst of messages to be sent. This helps users understand that the rate limiting is not permanent but operates in periodic windows. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250714-docs_ratelimit-v1-1-51a6d9071f1a@debian.org
2025-07-17Merge back earlier cpufreq material for 6.17-rc1Rafael J. Wysocki
2025-07-17Merge back earlier material related to system sleepRafael J. Wysocki
2025-07-16Documentation: amd-pstate:fix minimum performance state label errorshouyeliu
In the AMD P-States Performance Scale diagram, the labels for "Max Perf" and "Lowest Perf" were incorrectly used to define the range for "Desired Perf".The "Desired performance target" should be bounded by the "Maximum requested performance" and the "Minimum requested performance", which corresponds to "Max Perf" and "Min Perf", respectively. Signed-off-by: Shouye Liu <shouyeliu@tencent.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Link: https://lore.kernel.org/r/20250522070140.17557-1-shouyeliu@gmail.com Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
2025-07-16Documentation/kernel-parameters: Update rcu_normal_wake_from_gp docUladzislau Rezki (Sony)
Update the documentation about rcu_normal_wake_from_gp parameter. Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.upadhyay@kernel.org>
2025-07-14sched: Add CONFIG_SCHED_PROXY_EXEC & boot argument to enable/disableJohn Stultz
Add a CONFIG_SCHED_PROXY_EXEC option, along with a boot argument sched_proxy_exec= that can be used to disable the feature at boot time if CONFIG_SCHED_PROXY_EXEC was enabled. Also uses this option to allow the rq->donor to be different from rq->curr. Signed-off-by: John Stultz <jstultz@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com> Link: https://lkml.kernel.org/r/20250712033407.2383110-2-jstultz@google.com
2025-07-12Merge branch 'mm-hotfixes-stable' into mm-stable to pick up changes whichAndrew Morton
are required for a merge of the series "mm: folio_pte_batch() improvements".
2025-07-12Merge tag 'mm-hotfixes-stable-2025-07-11-16-16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "19 hotfixes. A whopping 16 are cc:stable and the remainder address post-6.15 issues or aren't considered necessary for -stable kernels. 14 are for MM. Three gdb-script fixes and a kallsyms build fix" * tag 'mm-hotfixes-stable-2025-07-11-16-16' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: Revert "sched/numa: add statistics of numa balance task" mm: fix the inaccurate memory statistics issue for users mm/damon: fix divide by zero in damon_get_intervals_score() samples/damon: fix damon sample mtier for start failure samples/damon: fix damon sample wsse for start failure samples/damon: fix damon sample prcl for start failure kasan: remove kasan_find_vm_area() to prevent possible deadlock scripts: gdb: vfs: support external dentry names mm/migrate: fix do_pages_stat in compat mode mm/damon/core: handle damon_call_control as normal under kdmond deactivation mm/rmap: fix potential out-of-bounds page table access during batched unmap mm/hugetlb: don't crash when allocating a folio if there are no resv scripts/gdb: de-reference per-CPU MCE interrupts scripts/gdb: fix interrupts.py after maple tree conversion maple_tree: fix mt_destroy_walk() on root leaf node mm/vmalloc: leave lazy MMU mode on PTE mapping error scripts/gdb: fix interrupts display after MCP on x86 lib/alloc_tag: do not acquire non-existent lock in alloc_tag_top_users() kallsyms: fix build without execinfo
2025-07-11Documentation/x86: Document new attack vector controlsDavid Kaplan
Document the 5 new attack vector command line options, how they interact with existing vulnerability controls, and recommendations on when they can be disabled. Note that while mitigating against untrusted userspace requires both user-to-kernel and user-to-user protection, these are kept separate. The kernel can control what code executes inside of it and that may affect the risk associated with vulnerabilities especially if new kernel mitigations are implemented. The same isn't typically true of userspace. In other words, the risk associated with user-to-user or guest-to-guest attacks is unlikely to change over time. While the risk associated with user-to-kernel or guest-to-host attacks may change. Therefore, these controls are separated. Signed-off-by: David Kaplan <david.kaplan@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250709155731.3279419-1-david.kaplan@amd.com
2025-07-10PM: sleep: add kernel parameter to disable asynchronous suspend/resumeTudor Ambarus
On some platforms, device dependencies are not properly represented by device links, which can cause issues when asynchronous power management is enabled. While it is possible to disable this via sysfs, doing so at runtime can race with the first system suspend event. This patch introduces a kernel command-line parameter, "pm_async", which can be set to "off" to globally disable asynchronous suspend and resume operations from early boot. It effectively provides a way to set the initial value of the existing pm_async sysfs knob at boot time. This offers a robust method to fall back to synchronous (sequential) operation, which can stabilize platforms with problematic dependencies and also serve as a useful debugging tool. The default behavior remains unchanged (asynchronous enabled). To disable it, boot the kernel with the "pm_async=off" parameter. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patch.msgid.link/20250709-pm-async-off-v3-1-cb69a6fc8d04@linaro.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-07-09Docs/admin-guide/mm/damon: add DAMON_STAT usage documentSeongJae Park
Document DAMON_STAT usage and add a link to it on DAMON admin-guide page. Link: https://lkml.kernel.org/r/20250604183127.13968-5-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09Revert "sched/numa: add statistics of numa balance task"Chen Yu
This reverts commit ad6b26b6a0a79166b53209df2ca1cf8636296382. This commit introduces per-memcg/task NUMA balance statistics, but unfortunately it introduced a NULL pointer exception due to the following race condition: After a swap task candidate was chosen, its mm_struct pointer was set to NULL due to task exit. Later, when performing the actual task swapping, the p->mm caused the problem. CPU0 CPU1 : ... task_numa_migrate task_numa_find_cpu task_numa_compare # a normal task p is chosen env->best_task = p # p exit: exit_signals(p); p->flags |= PF_EXITING exit_mm p->mm = NULL; migrate_swap_stop __migrate_swap_task((arg->src_task, arg->dst_cpu) count_memcg_event_mm(p->mm, NUMA_TASK_SWAP)# p->mm is NULL task_lock() should be held and the PF_EXITING flag needs to be checked to prevent this from happening. After discussion, the conclusion was that adding a lock is not worthwhile for some statistics calculations. Revert the change and rely on the tracepoint for this purpose. Link: https://lkml.kernel.org/r/20250704135620.685752-1-yu.c.chen@intel.com Link: https://lkml.kernel.org/r/20250708064917.BBD13C4CEED@smtp.kernel.org Fixes: ad6b26b6a0a7 ("sched/numa: add statistics of numa balance task") Signed-off-by: Chen Yu <yu.c.chen@intel.com> Reported-by: Jirka Hladky <jhladky@redhat.com> Closes: https://lore.kernel.org/all/CAE4VaGBLJxpd=NeRJXpSCuw=REhC5LWJpC29kDy-Zh2ZDyzQZA@mail.gmail.com/ Reported-by: Srikanth Aithal <Srikanth.Aithal@amd.com> Reported-by: Suneeth D <Suneeth.D@amd.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Hladky <jhladky@redhat.com> Cc: Libo Chen <libo.chen@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-09gpio: sim: allow to mark simulated lines as invalidBartosz Golaszewski
Add a new line-level, boolean property to the gpio-sim configfs interface called 'valid'. It's set by default and the user can unset it to make the line be included in the standard `gpio-reserved-ranges` property when the chip is registered with GPIO core. This allows users to specify which lines should not be available for requesting as GPIOs. Link: https://lore.kernel.org/r/20250630130358.40352-1-brgl@bgdev.pl Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-07-08Documentation: Remove duplicate word size in bootconfigSumeet Pawnikar
Remove duplicate word size in bootconfig.rst Signed-off-by: Sumeet Pawnikar <sumeet4linux@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250705151618.4806-1-sumeet4linux@gmail.com
2025-06-24smack: fix bug: setting task label silently ignores input garbageKonstantin Andreev
This command: # echo foo/bar >/proc/$$/attr/smack/current gives the task a label 'foo' w/o indication that label does not match input. Setting the label with lsm_set_self_attr() syscall behaves identically. This occures because: 1) smk_parse_smack() is used to convert input to a label 2) smk_parse_smack() takes only that part from the beginning of the input that looks like a label. 3) `/' is prohibited in labels, so only "foo" is taken. (2) is by design, because smk_parse_smack() is used for parsing strings which are more than just a label. Silent failure is not a good thing, and there are two indicators that this was not done intentionally: (size >= SMK_LONGLABEL) ~> invalid clause at the beginning of the do_setattr() and the "Returns the length of the smack label" claim in the do_setattr() description. So I fixed this by adding one tiny check: the taken label length == input length. Since input length is now strictly controlled, I changed the two ways of setting label smack_setselfattr(): lsm_set_self_attr() syscall smack_setprocattr(): > /proc/.../current to accommodate the divergence in what they understand by "input length": smack_setselfattr counts mandatory \0 into input length, smack_setprocattr does not. smack_setprocattr allows various trailers after label Related changes: * fixed description for smk_parse_smack * allow unprivileged tasks validate label syntax. * extract smk_parse_label_len() from smk_parse_smack() so parsing may be done w/o string allocation. * extract smk_import_valid_label() from smk_import_entry() to avoid repeated parsing. * smk_parse_smack(): scan null-terminated strings for no more than SMK_LONGLABEL(256) characters * smack_setselfattr(): require struct lsm_ctx . flags == 0 to reserve them for future. Fixes: e114e473771c ("Smack: Simplified Mandatory Access Control Kernel") Signed-off-by: Konstantin Andreev <andreev@swemel.ru> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2025-06-22smack: fix bug: invalid label of unix socket fileKonstantin Andreev
According to [1], the label of a UNIX domain socket (UDS) file (i.e., the filesystem object representing the socket) is not supposed to participate in Smack security. To achieve this, [1] labels UDS files with "*" in smack_d_instantiate(). Before [2], smack_d_instantiate() was responsible for initializing Smack security for all inodes, except ones under /proc [2] imposed the sole responsibility for initializing inode security for newly created filesystem objects on smack_inode_init_security(). However, smack_inode_init_security() lacks some logic present in smack_d_instantiate(). In particular, it does not label UDS files with "*". This patch adds the missing labeling of UDS files with "*" to smack_inode_init_security(). Labeling UDS files with "*" in smack_d_instantiate() still works for stale UDS files that already exist on disk. Stale UDS files are useless, but I keep labeling them for consistency and maybe to make easier for user to delete them. Compared to [1], this version introduces the following improvements: * UDS file label is held inside inode only and not saved to xattrs. * relabeling UDS files (setxattr, removexattr, etc.) is blocked. [1] 2010-11-24 Casey Schaufler commit b4e0d5f0791b ("Smack: UDS revision") [2] 2023-11-16 roberto.sassu Fixes: e63d86b8b764 ("smack: Initialize the in-memory inode in smack_inode_init_security()") Link: https://lore.kernel.org/linux-security-module/20231116090125.187209-5-roberto.sassu@huaweicloud.com/ Signed-off-by: Konstantin Andreev <andreev@swemel.ru> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2025-06-21Documentation/sysctl: coredump: add %F for pidfd numberSalvatore Bonaccorso
In commit b5325b2a270f ("coredump: hand a pidfd to the usermode coredump helper") a new core_pattern specifier, %F, was added to provide a pidfs to the usermode helper process referring to the crashed process. Update the documentation to include the new core_pattern specifier. Signed-off-by: Salvatore Bonaccorso <carnil@debian.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250612060204.1159734-1-carnil@debian.org
2025-06-21Documentation: amd-pstate:fix minimum performance state label errorShouye Liu
In the AMD P-States Performance Scale diagram, the labels for "Max Perf" and "Lowest Perf" were incorrectly used to define the range for "Desired Perf".The "Desired performance target" should be bounded by the "Maximum requested performance" and the "Minimum requested performance", which corresponds to "Max Perf" and "Min Perf", respectively. Signed-off-by: Shouye Liu <shouyeliu@tencent.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250620021658.92161-1-shouyeliu@gmail.com
2025-06-18cpufreq: docs: userspace: Explain HW coordination influenceShashank Balaji
Extend the "scaling_setspeed" sysfs attribute description in the userspace governor documentation to cover possible differences between the requested and actual CPU frequency. Signed-off-by: Shashank Balaji <shashank.mahadasyam@sony.com> Link: https://patch.msgid.link/20250527-userspace-governor-doc-v2-2-0e22c69920f2@sony.com [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-06-18documentation: add links to SELinux resourcesStephen Smalley
Add links to the SELinux kernel subsystem README.md file, the SELinux kernel wiki, and the SELinux userspace wiki to the SELinux guide. Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com> [PM: spacing and style corrections, subject tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2025-06-18vmcoreinfo: Remove documentation of PG_slab and PG_hugetlbMatthew Wilcox (Oracle)
The changes to kernel/vmcore_info.c were sadly not reflected in the documentation. Rectify that for both these flags as well as adding PAGE_UNACCEPTED_MAPCOUNT_VALUE. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Harry Yoo <harry.yoo@oracle.com> Link: https://patch.msgid.link/20250611155916.2579160-8-willy@infradead.org Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2025-06-18doc: Move SLUB documentation to the admin guideMatthew Wilcox (Oracle)
This section is supposed to be for internal documentation, while the document is advice for sysadmins. Move it to the appropriate place. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Harry Yoo <harry.yoo@oracle.com> Link: https://patch.msgid.link/20250611155916.2579160-2-willy@infradead.org Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2025-06-17x86/bugs: Add a Transient Scheduler Attacks mitigationBorislav Petkov (AMD)
Add the required features detection glue to bugs.c et all in order to support the TSA mitigation. Co-developed-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
2025-06-16x86/bugs: Rename MDS machinery to something more genericBorislav Petkov (AMD)
It will be used by other x86 mitigations. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
2025-06-16ima: add a knob ima= to allow disabling IMA in kdump kernelBaoquan He
Kdump kernel doesn't need IMA functionality, and enabling IMA will cost extra memory. It would be very helpful to allow IMA to be disabled for kdump kernel. Hence add a knob ima=on|off here to allow turning IMA off in kdump kernel if needed. Note that this IMA disabling is limited to kdump kernel, please don't abuse it in other kernel and thus serious consequences are caused. Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2025-06-13syscall_user_dispatch: Add PR_SYS_DISPATCH_INCLUSIVE_ONDmitry Vyukov
There are two possible scenarios for syscall filtering: - having a trusted/allowed range of PCs, and intercepting everything else - or the opposite: a single untrusted/intercepted range and allowing everything else (this is relevant for any kind of sandboxing scenario, or monitoring behavior of a single library) The current API only allows the former use case due to allowed range wrap-around check. Add PR_SYS_DISPATCH_INCLUSIVE_ON that enables the second use case. Add PR_SYS_DISPATCH_EXCLUSIVE_ON alias for PR_SYS_DISPATCH_ON to make it clear how it's different from the new PR_SYS_DISPATCH_INCLUSIVE_ON. Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/97947cc8e205ff49675826d7b0327ef2e2c66eea.1747839857.git.dvyukov@google.com
2025-06-13Documentation: ABI: Update WMI device paths in ABI docsArmin Wolf
The WMI driver core might append an ID to the WMI device name to avoid name collisions in case multiple WMI devices with the same GUID are present. Update all sysfs path referring to WMI devices to inform users about this important detail. Signed-off-by: Armin Wolf <W_Armin@gmx.de> Link: https://lore.kernel.org/r/20250610055526.23688-1-W_Armin@gmx.de Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-06-09smb: client: disable path remapping with POSIX extensionsPhilipp Kerling
If SMB 3.1.1 POSIX Extensions are available and negotiated, the client should be able to use all characters and not remap anything. Currently, the user has to explicitly request this behavior by specifying the "nomapposix" mount option. Link: https://lore.kernel.org/4195bb677b33d680e77549890a4f4dd3b474ceaf.camel@rx2.rx-server.de Signed-off-by: Philipp Kerling <pkerling@casix.org> Reviewed-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-09Documentation: cgroup: add section explaining controller availabilityVishal Chourasia
Add "Availability" section to Control Group v2 docs. It describes the meaning of a controller being available in a cgroup, complementing the existing "Enabling and Disabling" section. This update improves the clarity of cgroup controller management by explicitly distinguishing between: 1. Availability – when a controller is supported by the kernel and listed in "cgroup.controllers", making its interface files accessible in the cgroup's directory. 2. Enabling – when a controller is enabled via explicitly writing the name of the controller to "cgroup.subtree_control" to control distribution of resource across the cgroup's immediate children. As an example, consider /sys/fs/cgroup # cat cgroup.controllers cpuset cpu io memory hugetlb pids misc /sys/fs/cgroup # cat cgroup.subtree_control # No controllers enabled by default /sys/fs/cgroup # echo +cpu +memory > cgroup.subtree_control # enabling "cpu" and "memory" /sys/fs/cgroup # cat cgroup.subtree_control cpu memory # cpu and memory enabled in /sys/fs/cgroup /sys/fs/cgroup # mkdir foo_cgrp /sys/fs/cgroup # cd foo_cgrp/ /sys/fs/cgroup/foo_cgrp # cat cgroup.controllers cpu memory # cpu and memory available in 'foo_cgrp' /sys/fs/cgroup/foo_cgrp # cat cgroup.subtree_control # empty by default /sys/fs/cgroup/foo_cgrp # ls cgroup.controllers cpu.max.burst memory.numa_stat cgroup.events cpu.pressure memory.oom.group cgroup.freeze cpu.stat memory.peak cgroup.kill cpu.stat.local memory.pressure cgroup.max.depth cpu.weight memory.reclaim cgroup.max.descendants cpu.weight.nice memory.stat cgroup.pressure io.pressure memory.swap.current cgroup.procs memory.current memory.swap.events cgroup.stat memory.events memory.swap.high cgroup.subtree_control memory.events.local memory.swap.max cgroup.threads memory.high memory.swap.peak cgroup.type memory.low memory.zswap.current cpu.idle memory.max memory.zswap.max cpu.max memory.min memory.zswap.writeback In this example, "cpu" and "memory" are enabled in the root cgroup, making them available in "foo_cgrp". This exposes the corresponding interface files in "foo_cgrp/", allowing resource control of processes in that cgroup. However, these controllers are not yet enabled in "foo_cgrp" itself. Once a controller is available in a cgroup it can be used to resource control processes of the cgroup. Acked-by: Michal Koutný <mkoutny@suse.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Vishal Chourasia <vishalc@linux.ibm.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-06-09slab: Decouple slab_debug and no_hash_pointersKees Cook
Some system owners use slab_debug=FPZ (or similar) as a hardening option, but do not want to be forced into having kernel addresses exposed due to the implicit "no_hash_pointers" boot param setting.[1] Introduce the "hash_pointers" boot param, which defaults to "auto" (the current behavior), but also includes "always" (forcing on hashing even when "slab_debug=..." is defined), and "never". The existing "no_hash_pointers" boot param becomes an alias for "hash_pointers=never". This makes it possible to boot with "slab_debug=FPZ hash_pointers=always". Link: https://github.com/KSPP/linux/issues/368 [1] Fixes: 792702911f58 ("slub: force on no_hash_pointers when slub_debug is enabled") Co-developed-by: Sergio Perez Gonzalez <sperezglz@gmail.com> Signed-off-by: Sergio Perez Gonzalez <sperezglz@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Kees Cook <kees@kernel.org> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Rafael Aquini <raquini@redhat.com> Tested-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Link: https://patch.msgid.link/20250415170232.it.467-kees@kernel.org [kees@kernel.org: Add note about hash_pointers into slab_debug kernel parameter documentation.] Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-06-06Merge tag 'usb-6.16-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB / Thunderbolt updates from Greg KH: "Here is the big set of USB and Thunderbolt changes for 6.16-rc1. Included in here are the following: - USB offload support for audio devices. I think this takes the record for the most number of patch series (30+) over the longest period of time (2+ years) to get merged properly. Many props go to Wesley Cheng for seeing this effort through, they took a major out-of-tree hacked-up-monstrosity that was created by multiple vendors for their specific devices, got it all merged into a semi-coherent set of changes, and got all of the different major subsystems to agree on how this should be implemented both with changes to their code as well as userspace apis, AND wrangled the hardware companies into agreeing to go forward with this, despite making them all redo work they had already done in their private device trees. This feature offers major power savings on embedded devices where a USB audio stream can continue to flow while the rest of the system is sleeping, something that devices running on battery power really care about. There are still some more small tweaks left to be done here, and those patches are still out for review and arguing among the different hardware companies, but this is a major step forward and a great example of how to do upstream development well. - small number of thunderbolt fixes and updates, things seem to be slowing down here (famous last words...) - xhci refactors and reworking to try to handle some rough corner cases in some hardware implementations where things don't always work properly - typec driver updates - USB3 power management reworking and updates - Removal of some old and orphaned UDC gadget drivers that had not been used in a very long time, dropping over 11 thousand lines from the tree, always a nice thing, making up for the 12k lines added for the USB offload feature. - lots of little updates and fixes in different drivers All of these have been in linux-next for over 2 weeks, the USB offload logic has been in there for 8 weeks now, with no reported issues" * tag 'usb-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (172 commits) ALSA: usb-audio: qcom: fix USB_XHCI dependency ASoC: qdsp6: fix compile-testing without CONFIG_OF usb: misc: onboard_usb_dev: fix build warning for CONFIG_USB_ONBOARD_DEV_USB5744=n usb: typec: tipd: fix typo in TPS_STATUS_HIGH_VOLAGE_WARNING macro USB: typec: fix const issue in typec_match() USB: gadget: udc: fix const issue in gadget_match_driver() USB: gadget: fix up const issue with struct usb_function_instance USB: serial: pl2303: add new chip PL2303GC-Q20 and PL2303GT-2AB USB: serial: bus: fix const issue in usb_serial_device_match() usb: usbtmc: Fix timeout value in get_stb usb: usbtmc: Fix read_stb function and get_stb ioctl ALSA: qc_audio_offload: try to reduce address space confusion ALSA: qc_audio_offload: avoid leaking xfer_buf allocation ALSA: qc_audio_offload: rename dma/iova/va/cpu/phys variables ALSA: usb-audio: qcom: Fix an error handling path in qc_usb_audio_probe() usb: misc: onboard_usb_dev: Fix usb5744 initialization sequence dt-bindings: usb: ti,usb8041: Add binding for TI USB8044 hub controller usb: misc: onboard_usb_dev: Add support for TI TUSB8044 hub usb: gadget: lpc32xx_udc: Use USB API functions rather than constants usb: gadget: epautoconf: Use USB API functions rather than constants ...
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