user/sven/linux.git/kernel/events, branch v5.10.167

perf/core: Call LSM hook after copying perf_event_attr

2023-01-14T09:16:33Z

commit 0a041ebca4956292cadfb14a63ace3a9c1dcb0a3 upstream. It passes the attr struct to the security_perf_event_open() but it's not initialized yet. Fixes: da97e18458fb ("perf_event: Add support for LSM and SELinux checks") Signed-off-by: Namhyung Kim Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Joel Fernandes (Google) Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20221220223140.4020470-1-namhyung@kernel.org Signed-off-by: Greg Kroah-Hartman

perf: Fix possible memleak in pmu_dev_alloc()

2023-01-14T09:15:16Z

[ Upstream commit e8d7a90c08ce963c592fb49845f2ccc606a2ac21 ] In pmu_dev_alloc(), when dev_set_name() failed, it will goto free_dev and call put_device(pmu->dev) to release it. However pmu->dev->release is assigned after this, which makes warning and memleak. Call dev_set_name() after pmu->dev->release = pmu_dev_release to fix it. Device '(null)' does not have a release() function... WARNING: CPU: 2 PID: 441 at drivers/base/core.c:2332 device_release+0x1b9/0x240 ... Call Trace: kobject_put+0x17f/0x460 put_device+0x20/0x30 pmu_dev_alloc+0x152/0x400 perf_pmu_register+0x96b/0xee0 ... kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) unreferenced object 0xffff888014759000 (size 2048): comm "modprobe", pid 441, jiffies 4294931444 (age 38.332s) backtrace: [<0000000005aed3b4>] kmalloc_trace+0x27/0x110 [<000000006b38f9b8>] pmu_dev_alloc+0x50/0x400 [<00000000735f17be>] perf_pmu_register+0x96b/0xee0 [<00000000e38477f1>] 0xffffffffc0ad8603 [<000000004e162216>] do_one_initcall+0xd0/0x4e0 ... Fixes: abe43400579d ("perf: Sysfs enumeration") Signed-off-by: Chen Zhongjin Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20221111103653.91058-1-chenzhongjin@huawei.com Signed-off-by: Sasha Levin

signal: Add task_sigpending() helper

2023-01-04T10:39:17Z

[ Upstream commit 5c251e9dc0e127bac6fc5b8e6696363d2e35f515 ] This is in preparation for maintaining signal_pending() as the decider of whether or not a schedule() loop should be broken, or continue sleeping. This is different than the core signal use cases, which really need to know whether an actual signal is pending or not. task_sigpending() returns non-zero if TIF_SIGPENDING is set. Only core kernel use cases should care about the distinction between the two, make sure those use the task_sigpending() helper. Signed-off-by: Jens Axboe Signed-off-by: Thomas Gleixner Reviewed-by: Thomas Gleixner Reviewed-by: Oleg Nesterov Link: https://lore.kernel.org/r/20201026203230.386348-2-axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman

bpf, perf: Use subprog name when reporting subprog ksymbol

2022-12-08T10:23:54Z

[ Upstream commit 47df8a2f78bc34ff170d147d05b121f84e252b85 ] Since commit bfea9a8574f3 ("bpf: Add name to struct bpf_ksym"), when reporting subprog ksymbol to perf, prog name instead of subprog name is used. The backtrace of bpf program with subprogs will be incorrect as shown below: ffffffffc02deace bpf_prog_e44a3057dcb151f8_overwrite+0x66 ffffffffc02de9f7 bpf_prog_e44a3057dcb151f8_overwrite+0x9f ffffffffa71d8d4e trace_call_bpf+0xce ffffffffa71c2938 perf_call_bpf_enter.isra.0+0x48 overwrite is the entry program and it invokes the overwrite_htab subprog through bpf_loop, but in above backtrace, overwrite program just jumps inside itself. Fixing it by using subprog name when reporting subprog ksymbol. After the fix, the output of perf script will be correct as shown below: ffffffffc031aad2 bpf_prog_37c0bec7d7c764a4_overwrite_htab+0x66 ffffffffc031a9e7 bpf_prog_c7eb827ef4f23e71_overwrite+0x9f ffffffffa3dd8d4e trace_call_bpf+0xce ffffffffa3dc2938 perf_call_bpf_enter.isra.0+0x48 Fixes: bfea9a8574f3 ("bpf: Add name to struct bpf_ksym") Signed-off-by: Hou Tao Signed-off-by: Daniel Borkmann Acked-by: Jiri Olsa Link: https://lore.kernel.org/bpf/20221114095733.158588-1-houtao@huaweicloud.com Signed-off-by: Sasha Levin

perf/core: Fix data race between perf_event_set_output() and perf_mmap_close()

2022-07-29T15:19:11Z

[ Upstream commit 68e3c69803dada336893640110cb87221bb01dcf ] Yang Jihing reported a race between perf_event_set_output() and perf_mmap_close(): CPU1 CPU2 perf_mmap_close(e2) if (atomic_dec_and_test(&e2->rb->mmap_count)) // 1 - > 0 detach_rest = true ioctl(e1, IOC_SET_OUTPUT, e2) perf_event_set_output(e1, e2) ... list_for_each_entry_rcu(e, &e2->rb->event_list, rb_entry) ring_buffer_attach(e, NULL); // e1 isn't yet added and // therefore not detached ring_buffer_attach(e1, e2->rb) list_add_rcu(&e1->rb_entry, &e2->rb->event_list) After this; e1 is attached to an unmapped rb and a subsequent perf_mmap() will loop forever more: again: mutex_lock(&e->mmap_mutex); if (event->rb) { ... if (!atomic_inc_not_zero(&e->rb->mmap_count)) { ... mutex_unlock(&e->mmap_mutex); goto again; } } The loop in perf_mmap_close() holds e2->mmap_mutex, while the attach in perf_event_set_output() holds e1->mmap_mutex. As such there is no serialization to avoid this race. Change perf_event_set_output() to take both e1->mmap_mutex and e2->mmap_mutex to alleviate that problem. Additionally, have the loop in perf_mmap() detach the rb directly, this avoids having to wait for the concurrent perf_mmap_close() to get around to doing it to make progress. Fixes: 9bb5d40cd93c ("perf: Fix mmap() accounting hole") Reported-by: Yang Jihong Signed-off-by: Peter Zijlstra (Intel) Tested-by: Yang Jihong Link: https://lkml.kernel.org/r/YsQ3jm2GR38SW7uD@worktop.programming.kicks-ass.net Signed-off-by: Sasha Levin

perf: Fix sys_perf_event_open() race against self

2022-05-25T07:17:55Z

commit 3ac6487e584a1eb54071dbe1212e05b884136704 upstream. Norbert reported that it's possible to race sys_perf_event_open() such that the looser ends up in another context from the group leader, triggering many WARNs. The move_group case checks for races against itself, but the !move_group case doesn't, seemingly relying on the previous group_leader->ctx == ctx check. However, that check is racy due to not holding any locks at that time. Therefore, re-check the result after acquiring locks and bailing if they no longer match. Additionally, clarify the not_move_group case from the move_group-vs-move_group race. Fixes: f63a8daa5812 ("perf: Fix event->ctx locking") Reported-by: Norbert Slusarek Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

perf/core: Fix perf_mmap fail when CONFIG_PERF_USE_VMALLOC enabled

2022-04-27T11:53:56Z

[ Upstream commit 60490e7966659b26d74bf1fa4aa8693d9a94ca88 ] This problem can be reproduced with CONFIG_PERF_USE_VMALLOC enabled on both x86_64 and aarch64 arch when using sysdig -B(using ebpf)[1]. sysdig -B works fine after rebuilding the kernel with CONFIG_PERF_USE_VMALLOC disabled. I tracked it down to the if condition event->rb->nr_pages != nr_pages in perf_mmap is true when CONFIG_PERF_USE_VMALLOC is enabled where event->rb->nr_pages = 1 and nr_pages = 2048 resulting perf_mmap to return -EINVAL. This is because when CONFIG_PERF_USE_VMALLOC is enabled, rb->nr_pages is always equal to 1. Arch with CONFIG_PERF_USE_VMALLOC enabled by default: arc/arm/csky/mips/sh/sparc/xtensa Arch with CONFIG_PERF_USE_VMALLOC disabled by default: x86_64/aarch64/... Fix this problem by using data_page_nr() [1] https://github.com/draios/sysdig Fixes: 906010b2134e ("perf_event: Provide vmalloc() based mmap() backing") Signed-off-by: Zhipeng Xie Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220209145417.6495-1-xiezhipeng1@huawei.com Signed-off-by: Sasha Levin

perf/core: Fix address filter parser for multiple filters

2022-04-08T12:40:03Z

[ Upstream commit d680ff24e9e14444c63945b43a37ede7cd6958f9 ] Reset appropriate variables in the parser loop between parsing separate filters, so that they do not interfere with parsing the next filter. Fixes: 375637bc524952 ("perf/core: Introduce address range filtering") Signed-off-by: Adrian Hunter Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20220131072453.2839535-4-adrian.hunter@intel.com Signed-off-by: Sasha Levin

perf: Fix list corruption in perf_cgroup_switch()

2022-02-16T11:54:31Z

commit 5f4e5ce638e6a490b976ade4a40017b40abb2da0 upstream. There's list corruption on cgrp_cpuctx_list. This happens on the following path: perf_cgroup_switch: list_for_each_entry(cgrp_cpuctx_list) cpu_ctx_sched_in ctx_sched_in ctx_pinned_sched_in merge_sched_in perf_cgroup_event_disable: remove the event from the list Use list_for_each_entry_safe() to allow removing an entry during iteration. Fixes: 058fe1c0440e ("perf/core: Make cgroup switch visit only cpuctxs with cgroup events") Signed-off-by: Song Liu Reviewed-by: Rik van Riel Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220204004057.2961252-1-song@kernel.org Signed-off-by: Greg Kroah-Hartman

perf: Always wake the parent event

2022-02-16T11:54:20Z

[ Upstream commit 961c39121759ad09a89598ec4ccdd34ae0468a19 ] When using per-process mode and event inheritance is set to true, forked processes will create a new perf events via inherit_event() -> perf_event_alloc(). But these events will not have ring buffers assigned to them. Any call to wakeup will be dropped if it's called on an event with no ring buffer assigned because that's the object that holds the wakeup list. If the child event is disabled due to a call to perf_aux_output_begin() or perf_aux_output_end(), the wakeup is dropped leaving userspace hanging forever on the poll. Normally the event is explicitly re-enabled by userspace after it wakes up to read the aux data, but in this case it does not get woken up so the event remains disabled. This can be reproduced when using Arm SPE and 'stress' which forks once before running the workload. By looking at the list of aux buffers read, it's apparent that they stop after the fork: perf record -e arm_spe// -vvv -- stress -c 1 With this patch applied they continue to be printed. This behaviour doesn't happen when using systemwide or per-cpu mode. Reported-by: Ruben Ayrapetyan Signed-off-by: James Clark Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20211206113840.130802-2-james.clark@arm.com Signed-off-by: Sasha Levin