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2022-08-02Merge tag 'audit-pr-20220801' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "Two minor audit patches: on marks a function as static, the other removes a redundant length check" * tag 'audit-pr-20220801' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: make is_audit_feature_set() static audit: remove redundant data_len check
2022-08-02Merge tag 'execve-v5.20-rc1' of ↵Linus Torvalds2-2/+6
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull execve updates from Kees Cook: - Allow unsharing time namespace on vfork+exec (Andrei Vagin) - Replace usage of deprecated kmap APIs (Fabio M. De Francesco) - Fix spelling mistake (Zhang Jiaming) * tag 'execve-v5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: exec: Call kmap_local_page() in copy_string_kernel() exec: Fix a spelling mistake selftests/timens: add a test for vfork+exit fs/exec: allow to unshare a time namespace on vfork+exec
2022-08-02wireguard: ratelimiter: use hrtimer in selftestJason A. Donenfeld1-0/+1
Using msleep() is problematic because it's compared against ratelimiter.c's ktime_get_coarse_boottime_ns(), which means on systems with slow jiffies (such as UML's forced HZ=100), the result is inaccurate. So switch to using schedule_hrtimeout(). However, hrtimer gives us access only to the traditional posix timers, and none of the _COARSE variants. So now, rather than being too imprecise like jiffies, it's too precise. One solution would be to give it a large "range" value, but this will still fire early on a loaded system. A better solution is to align the timeout to the actual coarse timer, and then round up to the nearest tick, plus change. So add the timeout to the current coarse time, and then schedule_hrtimer() until the absolute computed time. This should hopefully reduce flakes in CI as well. Note that we keep the retry loop in case the entire function is running behind, because the test could still be scheduled out, by either the kernel or by the hypervisor's kernel, in which case restarting the test and hoping to not be scheduled out still helps. Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-02Merge tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-blockLinus Torvalds2-58/+43
Pull block updates from Jens Axboe: - Improve the type checking of request flags (Bart) - Ensure queue mapping for a single queues always picks the right queue (Bart) - Sanitize the io priority handling (Jan) - rq-qos race fix (Jinke) - Reserved tags handling improvements (John) - Separate memory alignment from file/disk offset aligment for O_DIRECT (Keith) - Add new ublk driver, userspace block driver using io_uring for communication with the userspace backend (Ming) - Use try_cmpxchg() to cleanup the code in various spots (Uros) - Finally remove bdevname() (Christoph) - Clean up the zoned device handling (Christoph) - Clean up independent access range support (Christoph) - Clean up and improve block sysfs handling (Christoph) - Clean up and improve teardown of block devices. This turns the usual two step process into something that is simpler to implement and handle in block drivers (Christoph) - Clean up chunk size handling (Christoph) - Misc cleanups and fixes (Bart, Bo, Dan, GuoYong, Jason, Keith, Liu, Ming, Sebastian, Yang, Ying) * tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block: (178 commits) ublk_drv: fix double shift bug ublk_drv: make sure that correct flags(features) returned to userspace ublk_drv: fix error handling of ublk_add_dev ublk_drv: fix lockdep warning block: remove __blk_get_queue block: call blk_mq_exit_queue from disk_release for never added disks blk-mq: fix error handling in __blk_mq_alloc_disk ublk: defer disk allocation ublk: rewrite ublk_ctrl_get_queue_affinity to not rely on hctx->cpumask ublk: fold __ublk_create_dev into ublk_ctrl_add_dev ublk: cleanup ublk_ctrl_uring_cmd ublk: simplify ublk_ch_open and ublk_ch_release ublk: remove the empty open and release block device operations ublk: remove UBLK_IO_F_PREFLUSH ublk: add a MAINTAINERS entry block: don't allow the same type rq_qos add more than once mmc: fix disk/queue leak in case of adding disk failure ublk_drv: fix an IS_ERR() vs NULL check ublk: remove UBLK_IO_F_INTEGRITY ublk_drv: remove unneeded semicolon ...
2022-08-02Merge tag 'for-5.20/io_uring-2022-07-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull io_uring updates from Jens Axboe: - As per (valid) complaint in the last merge window, fs/io_uring.c has grown quite large these days. io_uring isn't really tied to fs either, as it supports a wide variety of functionality outside of that. Move the code to io_uring/ and split it into files that either implement a specific request type, and split some code into helpers as well. The code is organized a lot better like this, and io_uring.c is now < 4K LOC (me). - Deprecate the epoll_ctl opcode. It'll still work, just trigger a warning once if used. If we don't get any complaints on this, and I don't expect any, then we can fully remove it in a future release (me). - Improve the cancel hash locking (Hao) - kbuf cleanups (Hao) - Efficiency improvements to the task_work handling (Dylan, Pavel) - Provided buffer improvements (Dylan) - Add support for recv/recvmsg multishot support. This is similar to the accept (or poll) support for have for multishot, where a single SQE can trigger everytime data is received. For applications that expect to do more than a few receives on an instantiated socket, this greatly improves efficiency (Dylan). - Efficiency improvements for poll handling (Pavel) - Poll cancelation improvements (Pavel) - Allow specifiying a range for direct descriptor allocations (Pavel) - Cleanup the cqe32 handling (Pavel) - Move io_uring types to greatly cleanup the tracing (Pavel) - Tons of great code cleanups and improvements (Pavel) - Add a way to do sync cancelations rather than through the sqe -> cqe interface, as that's a lot easier to use for some use cases (me). - Add support to IORING_OP_MSG_RING for sending direct descriptors to a different ring. This avoids the usually problematic SCM case, as we disallow those. (me) - Make the per-command alloc cache we use for apoll generic, place limits on it, and use it for netmsg as well (me). - Various cleanups (me, Michal, Gustavo, Uros) * tag 'for-5.20/io_uring-2022-07-29' of git://git.kernel.dk/linux-block: (172 commits) io_uring: ensure REQ_F_ISREG is set async offload net: fix compat pointer in get_compat_msghdr() io_uring: Don't require reinitable percpu_ref io_uring: fix types in io_recvmsg_multishot_overflow io_uring: Use atomic_long_try_cmpxchg in __io_account_mem io_uring: support multishot in recvmsg net: copy from user before calling __get_compat_msghdr net: copy from user before calling __copy_msghdr io_uring: support 0 length iov in buffer select in compat io_uring: fix multishot ending when not polled io_uring: add netmsg cache io_uring: impose max limit on apoll cache io_uring: add abstraction around apoll cache io_uring: move apoll cache to poll.c io_uring: consolidate hash_locked io-wq handling io_uring: clear REQ_F_HASH_LOCKED on hash removal io_uring: don't race double poll setting REQ_F_ASYNC_DATA io_uring: don't miss setting REQ_F_DOUBLE_POLL io_uring: disable multishot recvmsg io_uring: only trace one of complete or overflow ...
2022-08-02tracing/eprobe: Show syntax error logs in error_log fileMasami Hiramatsu (Google)2-3/+13
Show the syntax errors for event probes in error_log file as same as other dynamic events, so that user can understand what is the problem. Link: https://lkml.kernel.org/r/165932113556.2850673.3483079297896607612.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-02tracing: Use free_trace_buffer() in allocate_trace_buffers()Zhiqiang Liu1-14/+11
In allocate_trace_buffers(), if allocating tr->max_buffer fails, we can directly call free_trace_buffer to free tr->array_buffer. Link: https://lkml.kernel.org/r/65f0702d-07f6-08de-2a07-4c50af56a67b@huawei.com Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-02Merge tag 'pm-5.20-rc1' of ↵Linus Torvalds3-11/+30
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "These are mostly minor improvements all over including new CPU IDs for the Intel RAPL driver, an Energy Model rework to use micro-Watt as the power unit, cpufreq fixes and cleanus, cpuidle updates, devfreq updates, documentation cleanups and a new version of the pm-graph suite of utilities. Specifics: - Make cpufreq_show_cpus() more straightforward (Viresh Kumar). - Drop unnecessary CPU hotplug locking from store() used by cpufreq sysfs attributes (Viresh Kumar). - Make the ACPI cpufreq driver support the boost control interface on Zhaoxin/Centaur processors (Tony W Wang-oc). - Print a warning message on attempts to free an active cpufreq policy which should never happen (Viresh Kumar). - Fix grammar in the Kconfig help text for the loongson2 cpufreq driver (Randy Dunlap). - Use cpumask_var_t for an on-stack CPU mask in the ondemand cpufreq governor (Zhao Liu). - Add trace points for guest_halt_poll_ns grow/shrink to the haltpoll cpuidle driver (Eiichi Tsukata). - Modify intel_idle to treat C1 and C1E as independent idle states on Sapphire Rapids (Artem Bityutskiy). - Extend support for wakeirq to callback wrappers used during system suspend and resume (Ulf Hansson). - Defer waiting for device probe before loading a hibernation image till the first actual device access to avoid possible deadlocks reported by syzbot (Tetsuo Handa). - Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP (Bjorn Helgaas). - Add Raptor Lake-P to the list of processors supported by the Intel RAPL driver (George D Sworo). - Add Alder Lake-N and Raptor Lake-P to the list of processors for which Power Limit4 is supported in the Intel RAPL driver (Sumeet Pawnikar). - Make pm_genpd_remove() check genpd_debugfs_dir against NULL before attempting to remove it (Hsin-Yi Wang). - Change the Energy Model code to represent power in micro-Watts and adjust its users accordingly (Lukasz Luba). - Add new devfreq driver for Mediatek CCI (Cache Coherent Interconnect) (Johnson Wang). - Convert the Samsung Exynos SoC Bus bindings to DT schema of exynos-bus.c (Krzysztof Kozlowski). - Address kernel-doc warnings by adding the description for unused function parameters in devfreq core (Mauro Carvalho Chehab). - Use NULL to pass a null pointer rather than zero according to the function propotype in imx-bus.c (Colin Ian King). - Print error message instead of error interger value in tegra30-devfreq.c (Dmitry Osipenko). - Add checks to prevent setting negative frequency QoS limits for CPUs (Shivnandan Kumar). - Update the pm-graph suite of utilities to the latest revision 5.9 including multiple improvements (Todd Brandt). - Drop pme_interrupt reference from the PCI power management documentation (Mario Limonciello)" * tag 'pm-5.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (27 commits) powercap: RAPL: Add Power Limit4 support for Alder Lake-N and Raptor Lake-P PM: QoS: Add check to make sure CPU freq is non-negative PM: hibernate: defer device probing when resuming from hibernation intel_idle: make SPR C1 and C1E be independent cpufreq: ondemand: Use cpumask_var_t for on-stack cpu mask cpufreq: loongson2: fix Kconfig "its" grammar pm-graph v5.9 cpufreq: Warn users while freeing active policy cpufreq: scmi: Support the power scale in micro-Watts in SCMI v3.1 firmware: arm_scmi: Get detailed power scale from perf Documentation: EM: Switch to micro-Watts scale PM: EM: convert power field to micro-Watts precision and align drivers PM / devfreq: tegra30: Add error message for devm_devfreq_add_device() PM / devfreq: imx-bus: use NULL to pass a null pointer rather than zero PM / devfreq: shut up kernel-doc warnings dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema PM / devfreq: mediatek: Introduce MediaTek CCI devfreq driver dt-bindings: interconnect: Add MediaTek CCI dt-bindings PM: domains: Ensure genpd_debugfs_dir exists before remove PM: runtime: Extend support for wakeirq for force_suspend|resume ...
2022-08-02kprobes: Forbid probing on trampoline and BPF code areasChen Zhongjin1-1/+2
kernel_text_address() treats ftrace_trampoline, kprobe_insn_slot and bpf_text_address as valid kprobe addresses - which is not ideal. These text areas are removable and changeable without any notification to kprobes, and probing on them can trigger unexpected behavior: https://lkml.org/lkml/2022/7/26/1148 Considering that jump_label and static_call text are already forbiden to probe, kernel_text_address() should be replaced with core_kernel_text() and is_module_text_address() to check other text areas which are unsafe to kprobe. [ mingo: Rewrote the changelog. ] Fixes: 5b485629ba0d ("kprobes, extable: Identify kprobes trampolines as kernel text area") Fixes: 74451e66d516 ("bpf: make jited programs visible in traces") Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20220801033719.228248-1-chenzhongjin@huawei.com
2022-08-01Merge tag 'irq-core-2022-08-01' of ↵Linus Torvalds9-31/+30
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "Updates for interrupt core and drivers: Core: - Fix a few inconsistencies between UP and SMP vs interrupt affinities - Small updates and cleanups all over the place New drivers: - LoongArch interrupt controller - Renesas RZ/G2L interrupt controller Updates: - Hotpath optimization for SiFive PLIC - Workaround for broken PLIC edge triggered interrupts - Simall cleanups and improvements as usual" * tag 'irq-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) irqchip/mmp: Declare init functions in common header file irqchip/mips-gic: Check the return value of ioremap() in gic_of_init() genirq: Use for_each_action_of_desc in actions_show() irqchip / ACPI: Introduce ACPI_IRQ_MODEL_LPIC for LoongArch irqchip: Add LoongArch CPU interrupt controller support irqchip: Add Loongson Extended I/O interrupt controller support irqchip/loongson-liointc: Add ACPI init support irqchip/loongson-pch-msi: Add ACPI init support irqchip/loongson-pch-pic: Add ACPI init support irqchip: Add Loongson PCH LPC controller support LoongArch: Prepare to support multiple pch-pic and pch-msi irqdomain LoongArch: Use ACPI_GENERIC_GSI for gsi handling genirq/generic_chip: Export irq_unmap_generic_chip ACPI: irq: Allow acpi_gsi_to_irq() to have an arch-specific fallback APCI: irq: Add support for multiple GSI domains LoongArch: Provisionally add ACPICA data structures irqdomain: Use hwirq_max instead of revmap_size for NOMAP domains irqdomain: Report irq number for NOMAP domains irqchip/gic-v3: Fix comment typo dt-bindings: interrupt-controller: renesas,rzg2l-irqc: Document RZ/V2L SoC ...
2022-08-01Merge tag 'perf-core-2022-08-01' of ↵Linus Torvalds2-4/+22
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf events updates from Ingo Molnar: - Fix Intel Alder Lake PEBS memory access latency & data source profiling info bugs. - Use Intel large-PEBS hardware feature in more circumstances, to reduce PMI overhead & reduce sampling data. - Extend the lost-sample profiling output with the PERF_FORMAT_LOST ABI variant, which tells tooling the exact number of samples lost. - Add new IBS register bits definitions. - AMD uncore events: Add PerfMonV2 DF (Data Fabric) enhancements. * tag 'perf-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/ibs: Add new IBS register bits into header perf/x86/intel: Fix PEBS data source encoding for ADL perf/x86/intel: Fix PEBS memory access info encoding for ADL perf/core: Add a new read format to get a number of lost samples perf/x86/amd/uncore: Add PerfMonV2 RDPMC assignments perf/x86/amd/uncore: Add PerfMonV2 DF event format perf/x86/amd/uncore: Detect available DF counters perf/x86/amd/uncore: Use attr_update for format attributes perf/x86/amd/uncore: Use dynamic events array x86/events/intel/ds: Enable large PEBS for PERF_SAMPLE_WEIGHT_TYPE
2022-08-01Merge tag 'locking-core-2022-08-01' of ↵Linus Torvalds2-38/+10
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "This was a fairly quiet cycle for the locking subsystem: - lockdep: Fix a handful of the more complex lockdep_init_map_*() primitives that can lose the lock_type & cause false reports. No such mishap was observed in the wild. - jump_label improvements: simplify the cross-arch support of initial NOP patching by making it arch-specific code (used on MIPS only), and remove the s390 initial NOP patching that was superfluous" * tag 'locking-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/lockdep: Fix lockdep_init_map_*() confusion jump_label: make initial NOP patching the special case jump_label: mips: move module NOP patching into arch code jump_label: s390: avoid pointless initial NOP patching
2022-08-01Merge tag 'sched-core-2022-08-01' of ↵Linus Torvalds13-448/+837
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Load-balancing improvements: - Improve NUMA balancing on AMD Zen systems for affine workloads. - Improve the handling of reduced-capacity CPUs in load-balancing. - Energy Model improvements: fix & refine all the energy fairness metrics (PELT), and remove the conservative threshold requiring 6% energy savings to migrate a task. Doing this improves power efficiency for most workloads, and also increases the reliability of energy-efficiency scheduling. - Optimize/tweak select_idle_cpu() to spend (much) less time searching for an idle CPU on overloaded systems. There's reports of several milliseconds spent there on large systems with large workloads ... [ Since the search logic changed, there might be behavioral side effects. ] - Improve NUMA imbalance behavior. On certain systems with spare capacity, initial placement of tasks is non-deterministic, and such an artificial placement imbalance can persist for a long time, hurting (and sometimes helping) performance. The fix is to make fork-time task placement consistent with runtime NUMA balancing placement. Note that some performance regressions were reported against this, caused by workloads that are not memory bandwith limited, which benefit from the artificial locality of the placement bug(s). Mel Gorman's conclusion, with which we concur, was that consistency is better than random workload benefits from non-deterministic bugs: "Given there is no crystal ball and it's a tradeoff, I think it's better to be consistent and use similar logic at both fork time and runtime even if it doesn't have universal benefit." - Improve core scheduling by fixing a bug in sched_core_update_cookie() that caused unnecessary forced idling. - Improve wakeup-balancing by allowing same-LLC wakeup of idle CPUs for newly woken tasks. - Fix a newidle balancing bug that introduced unnecessary wakeup latencies. ABI improvements/fixes: - Do not check capabilities and do not issue capability check denial messages when a scheduler syscall doesn't require privileges. (Such as increasing niceness.) - Add forced-idle accounting to cgroups too. - Fix/improve the RSEQ ABI to not just silently accept unknown flags. (No existing tooling is known to have learned to rely on the previous behavior.) - Depreciate the (unused) RSEQ_CS_FLAG_NO_RESTART_ON_* flags. Optimizations: - Optimize & simplify leaf_cfs_rq_list() - Micro-optimize set_nr_{and_not,if}_polling() via try_cmpxchg(). Misc fixes & cleanups: - Fix the RSEQ self-tests on RISC-V and Glibc 2.35 systems. - Fix a full-NOHZ bug that can in some cases result in the tick not being re-enabled when the last SCHED_RT task is gone from a runqueue but there's still SCHED_OTHER tasks around. - Various PREEMPT_RT related fixes. - Misc cleanups & smaller fixes" * tag 'sched-core-2022-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits) rseq: Kill process when unknown flags are encountered in ABI structures rseq: Deprecate RSEQ_CS_FLAG_NO_RESTART_ON_* flags sched/core: Fix the bug that task won't enqueue into core tree when update cookie nohz/full, sched/rt: Fix missed tick-reenabling bug in dequeue_task_rt() sched/core: Always flush pending blk_plug sched/fair: fix case with reduced capacity CPU sched/core: Use try_cmpxchg in set_nr_{and_not,if}_polling sched/core: add forced idle accounting for cgroups sched/fair: Remove the energy margin in feec() sched/fair: Remove task_util from effective utilization in feec() sched/fair: Use the same cpumask per-PD throughout find_energy_efficient_cpu() sched/fair: Rename select_idle_mask to select_rq_mask sched, drivers: Remove max param from effective_cpu_util()/sched_cpu_util() sched/fair: Decay task PELT values during wakeup migration sched/fair: Provide u64 read for 32-bits arch helper sched/fair: Introduce SIS_UTIL to search idle CPU based on sum of util_avg sched: only perform capability check on privileged operation sched: Remove unused function group_first_cpu() sched/fair: Remove redundant word " *" selftests/rseq: check if libc rseq support is registered ...
2022-08-01rseq: Kill process when unknown flags are encountered in ABI structuresMathieu Desnoyers1-2/+2
rseq_abi()->flags and rseq_abi()->rseq_cs->flags 29 upper bits are currently unused. The current behavior when those bits are set is to ignore them. This is not an ideal behavior, because when future features will start using those flags, if user-space fails to correctly validate that the kernel indeed supports those flags (e.g. with a new sys_rseq flags bit) before using them, it may incorrectly assume that the kernel will handle those flags way when in fact those will be silently ignored on older kernels. Validating that unused flags bits are cleared will allow a smoother transition when those flags will start to be used by allowing applications to fail early, and obviously, when they attempt to use the new flags on an older kernel that does not support them. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20220622194617.1155957-2-mathieu.desnoyers@efficios.com
2022-08-01rseq: Deprecate RSEQ_CS_FLAG_NO_RESTART_ON_* flagsMathieu Desnoyers1-15/+8
The pretty much unused RSEQ_CS_FLAG_NO_RESTART_ON_* flags introduce complexity in rseq, and are subtly buggy [1]. Solving those issues requires introducing additional complexity in the rseq implementation for each supported architecture. Considering that it complexifies the rseq ABI, I am proposing that we deprecate those flags. [2] So far there appears to be consensus from maintainers of user-space projects impacted by this feature that its removal would be a welcome simplification. [3] The deprecation approach proposed here is to issue WARN_ON_ONCE() when encountering those flags and kill the offending process with sigsegv. This should allow us to quickly identify whether anyone yells at us for removing this. Link: https://lore.kernel.org/lkml/20220618182515.95831-1-minhquangbui99@gmail.com/ [1] Link: https://lore.kernel.org/lkml/258546133.12151.1655739550814.JavaMail.zimbra@efficios.com/ [2] Link: https://lore.kernel.org/lkml/87pmj1enjh.fsf@email.froward.int.ebiederm.org/ [3] Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/lkml/20220622194617.1155957-1-mathieu.desnoyers@efficios.com
2022-08-01kernel: remove platform_has() infrastructureJuergen Gross2-28/+1
The only use case of the platform_has() infrastructure has been removed again, so remove the whole feature. Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 guest using Xen Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/20220622063838.8854-3-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
2022-07-31Merge tag 'x86_urgent_for_v5.19' of ↵Linus Torvalds1-2/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Update the 'mitigations=' kernel param documentation - Check the IBPB feature flag before enabling IBPB in firmware calls because cloud vendors' fantasy when it comes to creating guest configurations is unlimited - Unexport sev_es_ghcb_hv_call() before 5.19 releases now that HyperV doesn't need it anymore - Remove dead CONFIG_* items * tag 'x86_urgent_for_v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: docs/kernel-parameters: Update descriptions for "mitigations=" param with retbleed x86/bugs: Do not enable IBPB at firmware entry when IBPB is not available Revert "x86/sev: Expose sev_es_ghcb_hv_call() for use by HyperV" x86/configs: Update configs in x86_debug.config
2022-07-31Merge tag 'locking_urgent_for_v5.19' of ↵Linus Torvalds1-10/+20
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fix from Borislav Petkov: - Avoid rwsem lockups in certain situations when handling the handoff bit * tag 'locking_urgent_for_v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rwsem: Allow slowpath writer to ignore handoff bit if not set by first waiter
2022-07-30rv/reactor: Add the panic reactorDaniel Bristot de Oliveira3-0/+52
Sample reactor that panics the system when an exception is found. This is useful both to capture a vmcore, or to fail-safe a critical system. Link: https://lkml.kernel.org/r/729aae3aba95f35738b8f8180e626d747d1d9da2.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv/reactor: Add the printk reactorDaniel Bristot de Oliveira3-1/+52
A reactor that printks the reaction message. Link: https://lkml.kernel.org/r/b65f18a7fd6dc6659a3008fd7b7392de3465d47b.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv/monitor: Add the wwnr monitorDaniel Bristot de Oliveira4-0/+146
Per task wakeup while not running (wwnr) monitor. This model is broken, the reason is that a task can be running in the processor without being set as RUNNABLE. Think about a task about to sleep: 1: set_current_state(TASK_UNINTERRUPTIBLE); 2: schedule(); And then imagine an IRQ happening in between the lines one and two, waking the task up. BOOM, the wakeup will happen while the task is running. Q: Why do we need this model, so? A: To test the reactors. Link: https://lkml.kernel.org/r/473c0fc39967250fdebcff8b620311c11dccad30.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv/monitor: Add the wip monitorDaniel Bristot de Oliveira3-36/+29
The wakeup in preemptive (wip) monitor verifies if the wakeup events always take place with preemption disabled: | | v #==================# H preemptive H <+ #==================# | | | | preempt_disable | preempt_enable v | sched_waking +------------------+ | +--------------- | | | | | non_preemptive | | +--------------> | | -+ +------------------+ The wakeup event always takes place with preemption disabled because of the scheduler synchronization. However, because the preempt_count and its trace event are not atomic with regard to interrupts, some inconsistencies might happen. The documentation illustrates one of these cases. Link: https://lkml.kernel.org/r/c98ca678df81115fddc04921b3c79720c836b18f.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv/monitor: Add the wip monitor skeleton created by dot2kDaniel Bristot de Oliveira2-0/+155
THIS CODE IS NOT LINKED TO THE MAKEFILE. This model does not compile because it lacks the instrumentation part, which will be added next. In the typical case, there will be only one patch, but it was split into two patches for educational purposes. This is the direct output this command line: $ dot2k -d tools/verification/models/wip.dot -t per_cpu Link: https://lkml.kernel.org/r/5eb7a9118917e8a814c5e49853a72fc62be0a101.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30Documentation/rv: Add a basic documentationDaniel Bristot de Oliveira2-0/+6
Add the runtime-verification.rst document, explaining the basics of RV and how to use the interface. Link: https://lkml.kernel.org/r/4be7d1a88ab1e2eb0767521e1ab52a149a154bc4.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv/include: Add deterministic automata monitor definition via C macrosDaniel Bristot de Oliveira3-0/+30
In Linux terms, the runtime verification monitors are encapsulated inside the "RV monitor" abstraction. The "RV monitor" includes a set of instances of the monitor (per-cpu monitor, per-task monitor, and so on), the helper functions that glue the monitor to the system reference model, and the trace output as a reaction for event parsing and exceptions, as depicted below: Linux +----- RV Monitor ----------------------------------+ Formal Realm | | Realm +-------------------+ +----------------+ +-----------------+ | Linux kernel | | Monitor | | Reference | | Tracing | -> | Instance(s) | <- | Model | | (instrumentation) | | (verification) | | (specification) | +-------------------+ +----------------+ +-----------------+ | | | | V | | +----------+ | | | Reaction | | | +--+--+--+-+ | | | | | | | | | +-> trace output ? | +------------------------|--|----------------------+ | +----> panic ? +-------> <user-specified> Add the rv/da_monitor.h, enabling automatic code generation for the *Monitor Instance(s)* using C macros, and code to support it. The benefits of the usage of macro for monitor synthesis are 3-fold as it: - Reduces the code duplication; - Facilitates the bug fix/improvement; - Avoids the case of developers changing the core of the monitor code to manipulate the model in a (let's say) non-standard way. This initial implementation presents three different types of monitor instances: - DECLARE_DA_MON_GLOBAL(name, type) - DECLARE_DA_MON_PER_CPU(name, type) - DECLARE_DA_MON_PER_TASK(name, type) The first declares the functions for a global deterministic automata monitor, the second for monitors with per-cpu instances, and the third with per-task instances. Link: https://lkml.kernel.org/r/51b0bf425a281e226dfeba7401d2115d6091f84e.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv: Add runtime reactors interfaceDaniel Bristot de Oliveira5-0/+564
A runtime monitor can cause a reaction to the detection of an exception on the model's execution. By default, the monitors have tracing reactions, printing the monitor output via tracepoints. But other reactions can be added (on-demand) via this interface. The user interface resembles the kernel tracing interface and presents these files: "available_reactors" - Reading shows the available reactors, one per line. For example: # cat available_reactors nop panic printk "reacting_on" - It is an on/off general switch for reactors, disabling all reactions. "monitors/MONITOR/reactors" - List available reactors, with the select reaction for the given MONITOR inside []. The default one is the nop (no operation) reactor. - Writing the name of a reactor enables it to the given MONITOR. For example: # cat monitors/wip/reactors [nop] panic printk # echo panic > monitors/wip/reactors # cat monitors/wip/reactors nop [panic] printk Link: https://lkml.kernel.org/r/1794eb994637457bdeaa6bad0b8263d2f7eece0c.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv: Add Runtime Verification (RV) interfaceDaniel Bristot de Oliveira8-0/+844
RV is a lightweight (yet rigorous) method that complements classical exhaustive verification techniques (such as model checking and theorem proving) with a more practical approach to complex systems. RV works by analyzing the trace of the system's actual execution, comparing it against a formal specification of the system behavior. RV can give precise information on the runtime behavior of the monitored system while enabling the reaction for unexpected events, avoiding, for example, the propagation of a failure on safety-critical systems. The development of this interface roots in the development of the paper: De Oliveira, Daniel Bristot; Cucinotta, Tommaso; De Oliveira, Romulo Silva. Efficient formal verification for the Linux kernel. In: International Conference on Software Engineering and Formal Methods. Springer, Cham, 2019. p. 315-332. And: De Oliveira, Daniel Bristot. Automata-based formal analysis and verification of the real-time Linux kernel. PhD Thesis, 2020. The RV interface resembles the tracing/ interface on purpose. The current path for the RV interface is /sys/kernel/tracing/rv/. It presents these files: "available_monitors" - List the available monitors, one per line. For example: # cat available_monitors wip wwnr "enabled_monitors" - Lists the enabled monitors, one per line; - Writing to it enables a given monitor; - Writing a monitor name with a '!' prefix disables it; - Truncating the file disables all enabled monitors. For example: # cat enabled_monitors # echo wip > enabled_monitors # echo wwnr >> enabled_monitors # cat enabled_monitors wip wwnr # echo '!wip' >> enabled_monitors # cat enabled_monitors wwnr # echo > enabled_monitors # cat enabled_monitors # Note that more than one monitor can be enabled concurrently. "monitoring_on" - It is an on/off general switcher for monitoring. Note that it does not disable enabled monitors or detach events, but stop the per-entity monitors of monitoring the events received from the system. It resembles the "tracing_on" switcher. "monitors/" Each monitor will have its one directory inside "monitors/". There the monitor specific files will be presented. The "monitors/" directory resembles the "events" directory on tracefs. For example: # cd monitors/wip/ # ls desc enable # cat desc wakeup in preemptive per-cpu testing monitor. # cat enable 0 For further information, see the comments in the header of kernel/trace/rv/rv.c from this patch. Link: https://lkml.kernel.org/r/a4bfe038f50cb047bfb343ad0e12b0e646ab308b.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30locking/rwsem: Allow slowpath writer to ignore handoff bit if not set by ↵Waiman Long1-10/+20
first waiter With commit d257cc8cb8d5 ("locking/rwsem: Make handoff bit handling more consistent"), the writer that sets the handoff bit can be interrupted out without clearing the bit if the wait queue isn't empty. This disables reader and writer optimistic lock spinning and stealing. Now if a non-first writer in the queue is somehow woken up or a new waiter enters the slowpath, it can't acquire the lock. This is not the case before commit d257cc8cb8d5 as the writer that set the handoff bit will clear it when exiting out via the out_nolock path. This is less efficient as the busy rwsem stays in an unlock state for a longer time. In some cases, this new behavior may cause lockups as shown in [1] and [2]. This patch allows a non-first writer to ignore the handoff bit if it is not originally set or initiated by the first waiter. This patch is shown to be effective in fixing the lockup problem reported in [1]. [1] https://lore.kernel.org/lkml/20220617134325.GC30825@techsingularity.net/ [2] https://lore.kernel.org/lkml/3f02975c-1a9d-be20-32cf-f1d8e3dfafcc@oracle.com/ Fixes: d257cc8cb8d5 ("locking/rwsem: Make handoff bit handling more consistent") Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: John Donnelly <john.p.donnelly@oracle.com> Tested-by: Mel Gorman <mgorman@techsingularity.net> Link: https://lore.kernel.org/r/20220622200419.778799-1-longman@redhat.com
2022-07-29Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski3-6/+9
Andrii Nakryiko says: ==================== bpf-next 2022-07-29 We've added 22 non-merge commits during the last 4 day(s) which contain a total of 27 files changed, 763 insertions(+), 120 deletions(-). The main changes are: 1) Fixes to allow setting any source IP with bpf_skb_set_tunnel_key() helper, from Paul Chaignon. 2) Fix for bpf_xdp_pointer() helper when doing sanity checking, from Joanne Koong. 3) Fix for XDP frame length calculation, from Lorenzo Bianconi. 4) Libbpf BPF_KSYSCALL docs improvements and fixes to selftests to accommodate s390x quirks with socketcall(), from Ilya Leoshkevich. 5) Allow/denylist and CI configs additions to selftests/bpf to improve BPF CI, from Daniel Müller. 6) BPF trampoline + ftrace follow up fixes, from Song Liu and Xu Kuohai. 7) Fix allocation warnings in netdevsim, from Jakub Kicinski. 8) bpf_obj_get_opts() libbpf API allowing to provide file flags, from Joe Burton. 9) vsnprintf usage fix in bpf_snprintf_btf(), from Fedor Tokarev. 10) Various small fixes and clean ups, from Daniel Müller, Rongguang Wei, Jörn-Thorben Hinz, Yang Li. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (22 commits) bpf: Remove unneeded semicolon libbpf: Add bpf_obj_get_opts() netdevsim: Avoid allocation warnings triggered from user space bpf: Fix NULL pointer dereference when registering bpf trampoline bpf: Fix test_progs -j error with fentry/fexit tests selftests/bpf: Bump internal send_signal/send_signal_tracepoint timeout bpftool: Don't try to return value from void function in skeleton bpftool: Replace sizeof(arr)/sizeof(arr[0]) with ARRAY_SIZE macro bpf: btf: Fix vsnprintf return value check libbpf: Support PPC in arch_specific_syscall_pfx selftests/bpf: Adjust vmtest.sh to use local kernel configuration selftests/bpf: Copy over libbpf configs selftests/bpf: Sort configuration selftests/bpf: Attach to socketcall() in test_probe_user libbpf: Extend BPF_KSYSCALL documentation bpf, devmap: Compute proper xdp_frame len redirecting frames bpf: Fix bpf_xdp_pointer return pointer selftests/bpf: Don't assign outer source IP to host bpf: Set flow flag to allow any source IP in bpf_tunnel_key geneve: Use ip_tunnel_key flow flags in route lookups ... ==================== Link: https://lore.kernel.org/r/20220729230948.1313527-1-andrii@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-29profile: setup_profiling_timer() is moslty not implementedBen Dooks1-2/+6
The setup_profiling_timer() is mostly un-implemented by many architectures. In many places it isn't guarded by CONFIG_PROFILE which is needed for it to be used. Make it a weak symbol in kernel/profile.c and remove the 'return -EINVAL' implementations from the kenrel. There are a couple of architectures which do return 0 from the setup_profiling_timer() function but they don't seem to do anything else with it. To keep the /proc compatibility for now, leave these for a future update or removal. On ARM, this fixes the following sparse warning: arch/arm/kernel/smp.c:793:5: warning: symbol 'setup_profiling_timer' was not declared. Should it be static? Link: https://lkml.kernel.org/r/20220721195509.418205-1-ben-linux@fluff.org Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-29kernel/hung_task: fix address space of proc_dohung_task_timeout_secsBen Dooks1-1/+1
The proc_dohung_task_timeout_secs() function is incorrectly marked as having a __user buffer as argument 3. However this is not the case and it is casing multiple sparse warnings. Fix the following warnings by removing __user from the argument: kernel/hung_task.c:237:52: warning: incorrect type in argument 3 (different address spaces) kernel/hung_task.c:237:52: expected void * kernel/hung_task.c:237:52: got void [noderef] __user *buffer kernel/hung_task.c:287:35: warning: incorrect type in initializer (incompatible argument 3 (different address spaces)) kernel/hung_task.c:287:35: expected int ( [usertype] *proc_handler )( ... ) kernel/hung_task.c:287:35: got int ( * )( ... ) kernel/hung_task.c:295:35: warning: incorrect type in initializer (incompatible argument 3 (different address spaces)) kernel/hung_task.c:295:35: expected int ( [usertype] *proc_handler )( ... ) kernel/hung_task.c:295:35: got int ( * )( ... ) Link: https://lkml.kernel.org/r/20220714074744.189017-1-ben.dooks@sifive.com Signed-off-by: Ben Dooks <ben.dooks@sifive.com> Cc: <Conor.Dooley@microchip.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-29bpf: Remove unneeded semicolonYang Li1-1/+1
Eliminate the following coccicheck warning: /kernel/bpf/trampoline.c:101:2-3: Unneeded semicolon Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220725222733.55613-1-yang.lee@linux.alibaba.com
2022-07-29bpf: Fix NULL pointer dereference when registering bpf trampolineXu Kuohai1-1/+4
A panic was reported on arm64: [ 44.517109] audit: type=1334 audit(1658859870.268:59): prog-id=19 op=LOAD [ 44.622031] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 [ 44.624321] Mem abort info: [ 44.625049] ESR = 0x0000000096000004 [ 44.625935] EC = 0x25: DABT (current EL), IL = 32 bits [ 44.627182] SET = 0, FnV = 0 [ 44.627930] EA = 0, S1PTW = 0 [ 44.628684] FSC = 0x04: level 0 translation fault [ 44.629788] Data abort info: [ 44.630474] ISV = 0, ISS = 0x00000004 [ 44.631362] CM = 0, WnR = 0 [ 44.632041] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000100ab5000 [ 44.633494] [0000000000000010] pgd=0000000000000000, p4d=0000000000000000 [ 44.635202] Internal error: Oops: 96000004 [#1] SMP [ 44.636452] Modules linked in: xfs crct10dif_ce ghash_ce virtio_blk virtio_console virtio_mmio qemu_fw_cfg [ 44.638713] CPU: 2 PID: 1 Comm: systemd Not tainted 5.19.0-rc7 #1 [ 44.640164] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 44.641799] pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 44.643404] pc : ftrace_set_filter_ip+0x24/0xa0 [ 44.644659] lr : bpf_trampoline_update.constprop.0+0x428/0x4a0 [ 44.646118] sp : ffff80000803b9f0 [ 44.646950] x29: ffff80000803b9f0 x28: ffff0b5d80364400 x27: ffff80000803bb48 [ 44.648721] x26: ffff8000085ad000 x25: ffff0b5d809d2400 x24: 0000000000000000 [ 44.650493] x23: 00000000ffffffed x22: ffff0b5dd7ea0900 x21: 0000000000000000 [ 44.652279] x20: 0000000000000000 x19: 0000000000000000 x18: ffffffffffffffff [ 44.654067] x17: 0000000000000000 x16: 0000000000000000 x15: ffffffffffffffff [ 44.655787] x14: ffff0b5d809d2498 x13: ffff0b5d809d2432 x12: 0000000005f5e100 [ 44.657535] x11: abcc77118461cefd x10: 000000000000005f x9 : ffffa7219cb5b190 [ 44.659254] x8 : ffffa7219c8e0000 x7 : 0000000000000000 x6 : ffffa7219db075e0 [ 44.661066] x5 : ffffa7219d3130e0 x4 : ffffa7219cab9da0 x3 : 0000000000000000 [ 44.662837] x2 : 0000000000000000 x1 : ffffa7219cb7a5c0 x0 : 0000000000000000 [ 44.664675] Call trace: [ 44.665274] ftrace_set_filter_ip+0x24/0xa0 [ 44.666327] bpf_trampoline_update.constprop.0+0x428/0x4a0 [ 44.667696] __bpf_trampoline_link_prog+0xcc/0x1c0 [ 44.668834] bpf_trampoline_link_prog+0x40/0x64 [ 44.669919] bpf_tracing_prog_attach+0x120/0x490 [ 44.671011] link_create+0xe0/0x2b0 [ 44.671869] __sys_bpf+0x484/0xd30 [ 44.672706] __arm64_sys_bpf+0x30/0x40 [ 44.673678] invoke_syscall+0x78/0x100 [ 44.674623] el0_svc_common.constprop.0+0x4c/0xf4 [ 44.675783] do_el0_svc+0x38/0x4c [ 44.676624] el0_svc+0x34/0x100 [ 44.677429] el0t_64_sync_handler+0x11c/0x150 [ 44.678532] el0t_64_sync+0x190/0x194 [ 44.679439] Code: 2a0203f4 f90013f5 2a0303f5 f9001fe1 (f9400800) [ 44.680959] ---[ end trace 0000000000000000 ]--- [ 44.682111] Kernel panic - not syncing: Oops: Fatal exception [ 44.683488] SMP: stopping secondary CPUs [ 44.684551] Kernel Offset: 0x2721948e0000 from 0xffff800008000000 [ 44.686095] PHYS_OFFSET: 0xfffff4a380000000 [ 44.687144] CPU features: 0x010,00022811,19001080 [ 44.688308] Memory Limit: none [ 44.689082] ---[ end Kernel panic - not syncing: Oops: Fatal exception ]--- It's caused by a NULL tr->fops passed to ftrace_set_filter_ip(). tr->fops is initialized to NULL and is assigned to an allocated memory address if CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS is enabled. Since there is no direct call on arm64 yet, the config can't be enabled. To fix it, call ftrace_set_filter_ip() only if tr->fops is not NULL. Fixes: 00963a2e75a8 ("bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)") Reported-by: Bruno Goncalves <bgoncalv@redhat.com> Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: Bruno Goncalves <bgoncalv@redhat.com> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20220728114048.3540461-1-xukuohai@huaweicloud.com
2022-07-29bpf: Fix test_progs -j error with fentry/fexit testsSong Liu1-1/+1
When multiple threads are attaching/detaching fentry/fexit programs to the same trampoline, we may call register_fentry on the same trampoline twice: register_fentry(), unregister_fentry(), then register_fentry again. This causes ftrace_set_filter_ip() for the same ip on tr->fops twice, which leaves duplicated ip in tr->fops. The extra ip is not cleaned up properly on unregister and thus causes failures with further register in register_ftrace_direct_multi(): register_ftrace_direct_multi() { ... for (i = 0; i < size; i++) { hlist_for_each_entry(entry, &hash->buckets[i], hlist) { if (ftrace_find_rec_direct(entry->ip)) goto out_unlock; } } ... } This can be triggered with parallel fentry/fexit tests with test_progs: ./test_progs -t fentry,fexit -j Fix this by resetting tr->fops in ftrace_set_filter_ip(), so that there will never be duplicated entries in tr->fops. Fixes: 00963a2e75a8 ("bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)") Reported-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220729194106.1207472-1-song@kernel.org
2022-07-29Merge tag 'wq-for-5.19-rc8-fixes' of ↵Linus Torvalds1-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue fix from Tejun Heo: "Just one commit to suppress a spurious warning added during the 5.19 cycle" * tag 'wq-for-5.19-rc8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: Avoid a false warning in unbind_workers()
2022-07-29workqueue: Avoid a false warning in unbind_workers()Lai Jiangshan1-1/+4
Doing set_cpus_allowed_ptr() with wq_unbound_cpumask can be possible fails and trigger the false warning. Use cpu_possible_mask instead when wq_unbound_cpumask has no active CPUs. It is very easy to trigger the warning: Set wq_unbound_cpumask to a small set of CPUs. Offline all the CPUs of wq_unbound_cpumask. Offline an extra CPU and trigger the warning. Fixes: 10a5a651e3af ("workqueue: Restrict kworker in the offline CPU pool running on housekeeping CPUs") Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2022-07-29Merge branches 'pm-devfreq', 'pm-qos', 'pm-tools' and 'pm-docs'Rafael J. Wysocki1-2/+2
Merge devfreq changes, PM QoS change, and power management tools and documentation changes for v5.20-rc1: - Add new devfreq driver for Mediatek CCI (Cache Coherent Interconnect) (Johnson Wang). - Convert the Samsung Exynos SoC Bus bindings to DT schema of exynos-bus.c (Krzysztof Kozlowski). - Address kernel-doc warnings by adding the description for unused fucntion parameters in devfreq core (Mauro Carvalho Chehab). - Use NULL to pass a null pointer rather than zero according to the function propotype in imx-bus.c (Colin Ian King). - Print error message instead of error interger value in tegra30-devfreq.c (Dmitry Osipenko). - Add checks to prevent setting negative frequency QoS limits for CPUs (Shivnandan Kumar). - Update the pm-graph suite of utilities to the latest revision 5.9 including multiple improvements (Todd Brandt). - Drop pme_interrupt reference from the PCI power management documentation (Mario Limonciello). * pm-devfreq: PM / devfreq: tegra30: Add error message for devm_devfreq_add_device() PM / devfreq: imx-bus: use NULL to pass a null pointer rather than zero PM / devfreq: shut up kernel-doc warnings dt-bindings: interconnect: samsung,exynos-bus: convert to dtschema PM / devfreq: mediatek: Introduce MediaTek CCI devfreq driver dt-bindings: interconnect: Add MediaTek CCI dt-bindings * pm-qos: PM: QoS: Add check to make sure CPU freq is non-negative * pm-tools: pm-graph v5.9 * pm-docs: Documentation: PM: Drop pme_interrupt reference
2022-07-29Merge branches 'pm-core', 'pm-sleep', 'powercap', 'pm-domains' and 'pm-em'Rafael J. Wysocki2-9/+28
Merge core device power management changes for v5.20-rc1: - Extend support for wakeirq to callback wrappers used during system suspend and resume (Ulf Hansson). - Defer waiting for device probe before loading a hibernation image till the first actual device access to avoid possible deadlocks reported by syzbot (Tetsuo Handa). - Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP (Bjorn Helgaas). - Add Raptor Lake-P to the list of processors supported by the Intel RAPL driver (George D Sworo). - Add Alder Lake-N and Raptor Lake-P to the list of processors for which Power Limit4 is supported in the Intel RAPL driver (Sumeet Pawnikar). - Make pm_genpd_remove() check genpd_debugfs_dir against NULL before attempting to remove it (Hsin-Yi Wang). - Change the Energy Model code to represent power in micro-Watts and adjust its users accordingly (Lukasz Luba). * pm-core: PM: runtime: Extend support for wakeirq for force_suspend|resume * pm-sleep: PM: hibernate: defer device probing when resuming from hibernation PM: wakeup: Unify device_init_wakeup() for PM_SLEEP and !PM_SLEEP * powercap: powercap: RAPL: Add Power Limit4 support for Alder Lake-N and Raptor Lake-P powercap: intel_rapl: Add support for RAPTORLAKE_P * pm-domains: PM: domains: Ensure genpd_debugfs_dir exists before remove * pm-em: cpufreq: scmi: Support the power scale in micro-Watts in SCMI v3.1 firmware: arm_scmi: Get detailed power scale from perf Documentation: EM: Switch to micro-Watts scale PM: EM: convert power field to micro-Watts precision and align drivers
2022-07-29bpf: btf: Fix vsnprintf return value checkFedor Tokarev1-1/+1
vsnprintf returns the number of characters which would have been written if enough space had been available, excluding the terminating null byte. Thus, the return value of 'len_left' means that the last character has been dropped. Signed-off-by: Fedor Tokarev <ftokarev@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/bpf/20220711211317.GA1143610@laptop
2022-07-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-47/+114
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-28cgroup: Skip subtree root in cgroup_update_dfl_csses()Waiman Long1-0/+9
The cgroup_update_dfl_csses() function updates css associations when a cgroup's subtree_control file is modified. Any changes made to a cgroup's subtree_control file, however, will only affect its descendants but not the cgroup itself. So there is no point in migrating csses associated with that cgroup. We can skip them instead. Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2022-07-28watch_queue: Fix missing locking in add_watch_to_object()Linus Torvalds1-22/+36
If a watch is being added to a queue, it needs to guard against interference from addition of a new watch, manual removal of a watch and removal of a watch due to some other queue being destroyed. KEYCTL_WATCH_KEY guards against this for the same {key,queue} pair by holding the key->sem writelocked and by holding refs on both the key and the queue - but that doesn't prevent interaction from other {key,queue} pairs. While add_watch_to_object() does take the spinlock on the event queue, it doesn't take the lock on the source's watch list. The assumption was that the caller would prevent that (say by taking key->sem) - but that doesn't prevent interference from the destruction of another queue. Fix this by locking the watcher list in add_watch_to_object(). Fixes: c73be61cede5 ("pipe: Add general notification queue support") Reported-by: syzbot+03d7b43290037d1f87ca@syzkaller.appspotmail.com Signed-off-by: David Howells <dhowells@redhat.com> cc: keyrings@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-07-28watch_queue: Fix missing rcu annotationDavid Howells1-1/+1
Since __post_watch_notification() walks wlist->watchers with only the RCU read lock held, we need to use RCU methods to add to the list (we already use RCU methods to remove from the list). Fix add_watch_to_object() to use hlist_add_head_rcu() instead of hlist_add_head() for that list. Fixes: c73be61cede5 ("pipe: Add general notification queue support") Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-07-28swiotlb: fix passing local variable to debugfs_create_ulong()Tianyu Lan1-3/+9
Debugfs node will be run-timely checked and so local variable should be not passed to debugfs_create_ulong(). Fix it via debugfs_create_file() to create io_tlb_used node and calculate used io tlb number with fops_io_tlb_used attribute. Fixes: 20347fca71a3 ("swiotlb: split up the global swiotlb lock") Signed-off-by: Tianyu Lan <tiala@microsoft.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-07-28dma-mapping: reformat comment to suppress htmldoc warningLogan Gunthorpe1-9/+9
make html doc reports a cryptic warning with the commit named below: kernel/dma/mapping.c:258: WARNING: Option list ends without a blank line; unexpected unindent. Seems the parser is a bit fussy about the tabbing and having a single space tab causes the warning. To suppress the warning add another tab to the list and reindent everything. Fixes: 7c2645a2a30a ("dma-mapping: allow EREMOTEIO return code for P2PDMA transfers") Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-07-28Merge tag 'irqchip-5.20' of ↵Thomas Gleixner18-42/+135
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core Pull irqchip/genirq updates from Marc Zyngier: * Core code update: - Non-SMP IRQ affinity fixes, allowing UP kernel to behave similarly to SMP ones for the purpose of interrupt affinity - Let irq_set_chip_handler_name_locked() take a const struct irq_chip * - Tidy-up the NOMAP irqdomain API variant - Teach action_show() to use for_each_action_of_desc() - Make irq_chip_request_resources_parent() allow the parent callback to be optional - Remove dynamic allocations from populate_parent_alloc_arg() * New drivers: - Merge the long awaited IRQ support for the LoongArch architecture, with the provisional ACPICA update (to be reverted once the official support lands) - New Renesas RZ/G2L IRQC driver, equipped with its companion GPIO driver * Driver updates - Optimise the hot path operations for the SiFive PLIC, trading the locking for per-CPU priority masking masking operations which are apparently faster - Work around broken PLIC implementations that deal pretty badly with edge-triggered interrupts. Flag two implementations as affected. - Simplify the irq-stm32-exti driver, particularly the table that remaps the interrupts from exti to the GIC, reducing the memory usage - Convert the ocelot irq_chip to being immutable - Check ioremap() return value in the MIPS GIC driver - Move MMP driver init function declarations into the common .h - The obligatory typo fixes Link: https://lore.kernel.org/all/20220727192356.1860546-1-maz@kernel.org
2022-07-27cgroup: remove "no" prefixed mount optionsTejun Heo1-20/+4
30312730bd02 ("cgroup: Add "no" prefixed mount options") added "no" prefixed mount options to allow turning them off and 6a010a49b63a ("cgroup: Make !percpu threadgroup_rwsem operations optional") added one more "no" prefixed mount option. However, Michal pointed out that the "no" prefixed options aren't necessary in allowing mount options to be turned off: # grep group /proc/mounts cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,relatime,nsdelegate,memory_recursiveprot 0 0 # mount -o remount,nsdelegate,memory_recursiveprot none /sys/fs/cgroup # grep cgroup /proc/mounts cgroup2 /sys/fs/cgroup cgroup2 rw,relatime,nsdelegate,memory_recursiveprot 0 0 Note that this is different from the remount behavior when the mount(1) is invoked without the device argument - "none": # grep cgroup /proc/mounts cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot 0 0 # mount -o remount,nsdelegate,memory_recursiveprot /sys/fs/cgroup # grep cgroup /proc/mounts cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot 0 0 While a bit confusing, given that there is a way to turn off the options, there's no reason to have the explicit "no" prefixed options. Let's remove them. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2022-07-27x86/configs: Update configs in x86_debug.configLukas Bulwahn1-2/+1
Commit 4675ff05de2d ("kmemcheck: rip it out") removed kmemcheck and its corresponding build config KMEMCHECK. Commit 0f620cefd775 ("objtool: Rename "VMLINUX_VALIDATION" -> "NOINSTR_VALIDATION"") renamed the debug config option. Adjust x86_debug.config to those changes in debug configs. Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20220722121815.27535-1-lukas.bulwahn@gmail.com
2022-07-27watchdog: export lockup_detector_reconfigureLaurent Dufour1-5/+16
In some circumstances it may be interesting to reconfigure the watchdog from inside the kernel. On PowerPC, this may helpful before and after a LPAR migration (LPM) is initiated, because it implies some latencies, watchdog, and especially NMI watchdog is expected to be triggered during this operation. Reconfiguring the watchdog with a factor, would prevent it to happen too frequently during LPM. Rename lockup_detector_reconfigure() as __lockup_detector_reconfigure() and create a new function lockup_detector_reconfigure() calling __lockup_detector_reconfigure() under the protection of watchdog_mutex. Signed-off-by: Laurent Dufour <ldufour@linux.ibm.com> [mpe: Squash in build fix from Laurent, reported by Sachin] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20220713154729.80789-3-ldufour@linux.ibm.com
2022-07-26PM: QoS: Add check to make sure CPU freq is non-negativeShivnandan Kumar1-2/+2
CPU frequency should never be negative. If some client driver calls freq_qos_update_request with a negative value which will be very high in absolute terms, then frequency QoS sets max CPU freq at fmax as it considers it's absolute value but it will add plist node with negative priority. plist node has priority from INT_MIN (highest) to INT_MAX(lowest). Once priority is set as negative, another client will not be able to reduce CPU frequency. Adding check to make sure CPU freq is non-negative will fix this problem. Signed-off-by: Shivnandan Kumar <quic_kshivnan@quicinc.com> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>