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2023-05-11tracing/user_events: Ensure write index cannot be negativeBeau Belgrave
[ Upstream commit cd98c93286a30cc4588dfd02453bec63c2f4acf4 ] The write index indicates which event the data is for and accesses a per-file array. The index is passed by user processes during write() calls as the first 4 bytes. Ensure that it cannot be negative by returning -EINVAL to prevent out of bounds accesses. Update ftrace self-test to ensure this occurs properly. Link: https://lkml.kernel.org/r/20230425225107.8525-2-beaub@linux.microsoft.com Fixes: 7f5a08c79df3 ("user_events: Add minimal support for trace_event into ftrace") Reported-by: Doug Cook <dcook@linux.microsoft.com> Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-11tracing: Fix permissions for the buffer_percent fileOndrej Mosnacek
commit 4f94559f40ad06d627c0fdfc3319cec778a2845b upstream. This file defines both read and write operations, yet it is being created as read-only. This means that it can't be written to without the CAP_DAC_OVERRIDE capability. Fix the permissions to allow root to write to it without the need to override DAC perms. Link: https://lore.kernel.org/linux-trace-kernel/20230503140114.3280002-1-omosnace@redhat.com Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 03329f993978 ("tracing: Add tracefs file buffer_percentage") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-11ring-buffer: Sync IRQ works before buffer destructionJohannes Berg
commit 675751bb20634f981498c7d66161584080cc061e upstream. If something was written to the buffer just before destruction, it may be possible (maybe not in a real system, but it did happen in ARCH=um with time-travel) to destroy the ringbuffer before the IRQ work ran, leading this KASAN report (or a crash without KASAN): BUG: KASAN: slab-use-after-free in irq_work_run_list+0x11a/0x13a Read of size 8 at addr 000000006d640a48 by task swapper/0 CPU: 0 PID: 0 Comm: swapper Tainted: G W O 6.3.0-rc1 #7 Stack: 60c4f20f 0c203d48 41b58ab3 60f224fc 600477fa 60f35687 60c4f20f 601273dd 00000008 6101eb00 6101eab0 615be548 Call Trace: [<60047a58>] show_stack+0x25e/0x282 [<60c609e0>] dump_stack_lvl+0x96/0xfd [<60c50d4c>] print_report+0x1a7/0x5a8 [<603078d3>] kasan_report+0xc1/0xe9 [<60308950>] __asan_report_load8_noabort+0x1b/0x1d [<60232844>] irq_work_run_list+0x11a/0x13a [<602328b4>] irq_work_tick+0x24/0x34 [<6017f9dc>] update_process_times+0x162/0x196 [<6019f335>] tick_sched_handle+0x1a4/0x1c3 [<6019fd9e>] tick_sched_timer+0x79/0x10c [<601812b9>] __hrtimer_run_queues.constprop.0+0x425/0x695 [<60182913>] hrtimer_interrupt+0x16c/0x2c4 [<600486a3>] um_timer+0x164/0x183 [...] Allocated by task 411: save_stack_trace+0x99/0xb5 stack_trace_save+0x81/0x9b kasan_save_stack+0x2d/0x54 kasan_set_track+0x34/0x3e kasan_save_alloc_info+0x25/0x28 ____kasan_kmalloc+0x8b/0x97 __kasan_kmalloc+0x10/0x12 __kmalloc+0xb2/0xe8 load_elf_phdrs+0xee/0x182 [...] The buggy address belongs to the object at 000000006d640800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 584 bytes inside of freed 1024-byte region [000000006d640800, 000000006d640c00) Add the appropriate irq_work_sync() so the work finishes before the buffers are destroyed. Prior to the commit in the Fixes tag below, there was only a single global IRQ work, so this issue didn't exist. Link: https://lore.kernel.org/linux-trace-kernel/20230427175920.a76159263122.I8295e405c44362a86c995e9c2c37e3e03810aa56@changeid Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 15693458c4bc ("tracing/ring-buffer: Move poll wake ups into ring buffer code") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-11ring-buffer: Ensure proper resetting of atomic variables in ↵Tze-nan Wu
ring_buffer_reset_online_cpus commit 7c339fb4d8577792378136c15fde773cfb863cb8 upstream. In ring_buffer_reset_online_cpus, the buffer_size_kb write operation may permanently fail if the cpu_online_mask changes between two for_each_online_buffer_cpu loops. The number of increases and decreases on both cpu_buffer->resize_disabled and cpu_buffer->record_disabled may be inconsistent, causing some CPUs to have non-zero values for these atomic variables after the function returns. This issue can be reproduced by "echo 0 > trace" while hotplugging cpu. After reproducing success, we can find out buffer_size_kb will not be functional anymore. To prevent leaving 'resize_disabled' and 'record_disabled' non-zero after ring_buffer_reset_online_cpus returns, we ensure that each atomic variable has been set up before atomic_sub() to it. Link: https://lore.kernel.org/linux-trace-kernel/20230426062027.17451-1-Tze-nan.Wu@mediatek.com Cc: stable@vger.kernel.org Cc: <mhiramat@kernel.org> Cc: npiggin@gmail.com Fixes: b23d7a5f4a07 ("ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU") Reviewed-by: Cheng-Jui Wang <cheng-jui.wang@mediatek.com> Signed-off-by: Tze-nan Wu <Tze-nan.Wu@mediatek.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20tracing: Have tracing_snapshot_instance_cond() write errors to the ↵Steven Rostedt (Google)
appropriate instance [ Upstream commit 9d52727f8043cfda241ae96896628d92fa9c50bb ] If a trace instance has a failure with its snapshot code, the error message is to be written to that instance's buffer. But currently, the message is written to the top level buffer. Worse yet, it may also disable the top level buffer and not the instance that had the issue. Link: https://lkml.kernel.org/r/20230405022341.688730321@goodmis.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ross Zwisler <zwisler@google.com> Fixes: 2824f50332486 ("tracing: Make the snapshot trigger work with instances") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-20tracing: Add trace_array_puts() to write into instanceSteven Rostedt (Google)
[ Upstream commit d503b8f7474fe7ac616518f7fc49773cbab49f36 ] Add a generic trace_array_puts() that can be used to "trace_puts()" into an allocated trace_array instance. This is just another variant of trace_array_printk(). Link: https://lkml.kernel.org/r/20230207173026.584717290@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Ross Zwisler <zwisler@google.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Stable-dep-of: 9d52727f8043 ("tracing: Have tracing_snapshot_instance_cond() write errors to the appropriate instance") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-13ring-buffer: Fix race while reader and writer are on the same pageZheng Yejian
commit 6455b6163d8c680366663cdb8c679514d55fc30c upstream. When user reads file 'trace_pipe', kernel keeps printing following logs that warn at "cpu_buffer->reader_page->read > rb_page_size(reader)" in rb_get_reader_page(). It just looks like there's an infinite loop in tracing_read_pipe(). This problem occurs several times on arm64 platform when testing v5.10 and below. Call trace: rb_get_reader_page+0x248/0x1300 rb_buffer_peek+0x34/0x160 ring_buffer_peek+0xbc/0x224 peek_next_entry+0x98/0xbc __find_next_entry+0xc4/0x1c0 trace_find_next_entry_inc+0x30/0x94 tracing_read_pipe+0x198/0x304 vfs_read+0xb4/0x1e0 ksys_read+0x74/0x100 __arm64_sys_read+0x24/0x30 el0_svc_common.constprop.0+0x7c/0x1bc do_el0_svc+0x2c/0x94 el0_svc+0x20/0x30 el0_sync_handler+0xb0/0xb4 el0_sync+0x160/0x180 Then I dump the vmcore and look into the problematic per_cpu ring_buffer, I found that tail_page/commit_page/reader_page are on the same page while reader_page->read is obviously abnormal: tail_page == commit_page == reader_page == { .write = 0x100d20, .read = 0x8f9f4805, // Far greater than 0xd20, obviously abnormal!!! .entries = 0x10004c, .real_end = 0x0, .page = { .time_stamp = 0x857257416af0, .commit = 0xd20, // This page hasn't been full filled. // .data[0...0xd20] seems normal. } } The root cause is most likely the race that reader and writer are on the same page while reader saw an event that not fully committed by writer. To fix this, add memory barriers to make sure the reader can see the content of what is committed. Since commit a0fcaaed0c46 ("ring-buffer: Fix race between reset page and reading page") has added the read barrier in rb_get_reader_page(), here we just need to add the write barrier. Link: https://lore.kernel.org/linux-trace-kernel/20230325021247.2923907-1-zhengyejian1@huawei.com Cc: stable@vger.kernel.org Fixes: 77ae365eca89 ("ring-buffer: make lockless") Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-13tracing/synthetic: Make lastcmd_mutex staticSteven Rostedt (Google)
commit 31c683967174b487939efaf65e41f5ff1404e141 upstream. The lastcmd_mutex is only used in trace_events_synth.c and should be static. Link: https://lore.kernel.org/linux-trace-kernel/202304062033.cRStgOuP-lkp@intel.com/ Link: https://lore.kernel.org/linux-trace-kernel/20230406111033.6e26de93@gandalf.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Tze-nan Wu <Tze-nan.Wu@mediatek.com> Fixes: 4ccf11c4e8a8e ("tracing/synthetic: Fix races on freeing last_cmd") Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-13tracing: Free error logs of tracing instancesSteven Rostedt (Google)
commit 3357c6e429643231e60447b52ffbb7ac895aca22 upstream. When a tracing instance is removed, the error messages that hold errors that occurred in the instance needs to be freed. The following reports a memory leak: # cd /sys/kernel/tracing # mkdir instances/foo # echo 'hist:keys=x' > instances/foo/events/sched/sched_switch/trigger # cat instances/foo/error_log [ 117.404795] hist:sched:sched_switch: error: Couldn't find field Command: hist:keys=x ^ # rmdir instances/foo Then check for memory leaks: # echo scan > /sys/kernel/debug/kmemleak # cat /sys/kernel/debug/kmemleak unreferenced object 0xffff88810d8ec700 (size 192): comm "bash", pid 869, jiffies 4294950577 (age 215.752s) hex dump (first 32 bytes): 60 dd 68 61 81 88 ff ff 60 dd 68 61 81 88 ff ff `.ha....`.ha.... a0 30 8c 83 ff ff ff ff 26 00 0a 00 00 00 00 00 .0......&....... backtrace: [<00000000dae26536>] kmalloc_trace+0x2a/0xa0 [<00000000b2938940>] tracing_log_err+0x277/0x2e0 [<000000004a0e1b07>] parse_atom+0x966/0xb40 [<0000000023b24337>] parse_expr+0x5f3/0xdb0 [<00000000594ad074>] event_hist_trigger_parse+0x27f8/0x3560 [<00000000293a9645>] trigger_process_regex+0x135/0x1a0 [<000000005c22b4f2>] event_trigger_write+0x87/0xf0 [<000000002cadc509>] vfs_write+0x162/0x670 [<0000000059c3b9be>] ksys_write+0xca/0x170 [<00000000f1cddc00>] do_syscall_64+0x3e/0xc0 [<00000000868ac68c>] entry_SYSCALL_64_after_hwframe+0x72/0xdc unreferenced object 0xffff888170c35a00 (size 32): comm "bash", pid 869, jiffies 4294950577 (age 215.752s) hex dump (first 32 bytes): 0a 20 20 43 6f 6d 6d 61 6e 64 3a 20 68 69 73 74 . Command: hist 3a 6b 65 79 73 3d 78 0a 00 00 00 00 00 00 00 00 :keys=x......... backtrace: [<000000006a747de5>] __kmalloc+0x4d/0x160 [<000000000039df5f>] tracing_log_err+0x29b/0x2e0 [<000000004a0e1b07>] parse_atom+0x966/0xb40 [<0000000023b24337>] parse_expr+0x5f3/0xdb0 [<00000000594ad074>] event_hist_trigger_parse+0x27f8/0x3560 [<00000000293a9645>] trigger_process_regex+0x135/0x1a0 [<000000005c22b4f2>] event_trigger_write+0x87/0xf0 [<000000002cadc509>] vfs_write+0x162/0x670 [<0000000059c3b9be>] ksys_write+0xca/0x170 [<00000000f1cddc00>] do_syscall_64+0x3e/0xc0 [<00000000868ac68c>] entry_SYSCALL_64_after_hwframe+0x72/0xdc The problem is that the error log needs to be freed when the instance is removed. Link: https://lore.kernel.org/lkml/76134d9f-a5ba-6a0d-37b3-28310b4a1e91@alu.unizg.hr/ Link: https://lore.kernel.org/linux-trace-kernel/20230404194504.5790b95f@gandalf.local.home Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Thorsten Leemhuis <regressions@leemhuis.info> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Eric Biggers <ebiggers@kernel.org> Fixes: 2f754e771b1a6 ("tracing: Have the error logs show up in the proper instances") Reported-by: Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr> Tested-by: Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-13tracing/osnoise: Fix notify new tracing_max_latencyDaniel Bristot de Oliveira
commit d3cba7f02cd82118c32651c73374d8a5a459d9a6 upstream. osnoise/timerlat tracers are reporting new max latency on instances where the tracing is off, creating inconsistencies between the max reported values in the trace and in the tracing_max_latency. Thus only report new tracing_max_latency on active tracing instances. Link: https://lkml.kernel.org/r/ecd109fde4a0c24ab0f00ba1e9a144ac19a91322.1680104184.git.bristot@kernel.org Cc: stable@vger.kernel.org Fixes: dae181349f1e ("tracing/osnoise: Support a list of trace_array *tr") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-13tracing/timerlat: Notify new max thread latencyDaniel Bristot de Oliveira
commit b9f451a9029a16eb7913ace09b92493d00f2e564 upstream. timerlat is not reporting a new tracing_max_latency for the thread latency. The reason is that it is not calling notify_new_max_latency() function after the new thread latency is sampled. Call notify_new_max_latency() after computing the thread latency. Link: https://lkml.kernel.org/r/16e18d61d69073d0192ace07bf61e405cca96e9c.1680104184.git.bristot@kernel.org Cc: stable@vger.kernel.org Fixes: dae181349f1e ("tracing/osnoise: Support a list of trace_array *tr") Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-13tracing/synthetic: Fix races on freeing last_cmdTze-nan Wu
commit 4ccf11c4e8a8e051499d53a12f502196c97a758e upstream. Currently, the "last_cmd" variable can be accessed by multiple processes asynchronously when multiple users manipulate synthetic_events node at the same time, it could lead to use-after-free or double-free. This patch add "lastcmd_mutex" to prevent "last_cmd" from being accessed asynchronously. ================================================================ It's easy to reproduce in the KASAN environment by running the two scripts below in different shells. script 1: while : do echo -n -e '\x88' > /sys/kernel/tracing/synthetic_events done script 2: while : do echo -n -e '\xb0' > /sys/kernel/tracing/synthetic_events done ================================================================ double-free scenario: process A process B ------------------- --------------- 1.kstrdup last_cmd 2.free last_cmd 3.free last_cmd(double-free) ================================================================ use-after-free scenario: process A process B ------------------- --------------- 1.kstrdup last_cmd 2.free last_cmd 3.tracing_log_err(use-after-free) ================================================================ Appendix 1. KASAN report double-free: BUG: KASAN: double-free in kfree+0xdc/0x1d4 Free of addr ***** by task sh/4879 Call trace: ... kfree+0xdc/0x1d4 create_or_delete_synth_event+0x60/0x1e8 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Allocated by task 4879: ... kstrdup+0x5c/0x98 create_or_delete_synth_event+0x6c/0x1e8 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Freed by task 5464: ... kfree+0xdc/0x1d4 create_or_delete_synth_event+0x60/0x1e8 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... ================================================================ Appendix 2. KASAN report use-after-free: BUG: KASAN: use-after-free in strlen+0x5c/0x7c Read of size 1 at addr ***** by task sh/5483 sh: CPU: 7 PID: 5483 Comm: sh ... __asan_report_load1_noabort+0x34/0x44 strlen+0x5c/0x7c tracing_log_err+0x60/0x444 create_or_delete_synth_event+0xc4/0x204 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Allocated by task 5483: ... kstrdup+0x5c/0x98 create_or_delete_synth_event+0x80/0x204 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Freed by task 5480: ... kfree+0xdc/0x1d4 create_or_delete_synth_event+0x74/0x204 trace_parse_run_command+0x2bc/0x4b8 synth_events_write+0x20/0x30 vfs_write+0x200/0x830 ... Link: https://lore.kernel.org/linux-trace-kernel/20230321110444.1587-1-Tze-nan.Wu@mediatek.com Fixes: 27c888da9867 ("tracing: Remove size restriction on synthetic event cmd error logging") Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: "Tom Zanussi" <zanussi@kernel.org> Signed-off-by: Tze-nan Wu <Tze-nan.Wu@mediatek.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-13ftrace: Fix issue that 'direct->addr' not restored in modify_ftrace_direct()Zheng Yejian
commit 2a2d8c51defb446e8d89a83f42f8e5cd529111e9 upstream. Syzkaller report a WARNING: "WARN_ON(!direct)" in modify_ftrace_direct(). Root cause is 'direct->addr' was changed from 'old_addr' to 'new_addr' but not restored if error happened on calling ftrace_modify_direct_caller(). Then it can no longer find 'direct' by that 'old_addr'. To fix it, restore 'direct->addr' to 'old_addr' explicitly in error path. Link: https://lore.kernel.org/linux-trace-kernel/20230330025223.1046087-1-zhengyejian1@huawei.com Cc: stable@vger.kernel.org Cc: <mhiramat@kernel.org> Cc: <mark.rutland@arm.com> Cc: <ast@kernel.org> Cc: <daniel@iogearbox.net> Fixes: 8a141dd7f706 ("ftrace: Fix modify_ftrace_direct.") Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-06tracing: Fix wrong return in kprobe_event_gen_test.cAnton Gusev
[ Upstream commit bc4f359b3b607daac0290d0038561237a86b38cb ] Overwriting the error code with the deletion result may cause the function to return 0 despite encountering an error. Commit b111545d26c0 ("tracing: Remove the useless value assignment in test_create_synth_event()") solves a similar issue by returning the original error code, so this patch does the same. Found by Linux Verification Center (linuxtesting.org) with SVACE. Link: https://lore.kernel.org/linux-trace-kernel/20230131075818.5322-1-aagusev@ispras.ru Signed-off-by: Anton Gusev <aagusev@ispras.ru> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-30tracing/hwlat: Replace sched_setaffinity with set_cpus_allowed_ptrCosta Shulyupin
[ Upstream commit 71c7a30442b724717a30d5e7d1662ba4904eb3d4 ] There is a problem with the behavior of hwlat in a container, resulting in incorrect output. A warning message is generated: "cpumask changed while in round-robin mode, switching to mode none", and the tracing_cpumask is ignored. This issue arises because the kernel thread, hwlatd, is not a part of the container, and the function sched_setaffinity is unable to locate it using its PID. Additionally, the task_struct of hwlatd is already known. Ultimately, the function set_cpus_allowed_ptr achieves the same outcome as sched_setaffinity, but employs task_struct instead of PID. Test case: # cd /sys/kernel/tracing # echo 0 > tracing_on # echo round-robin > hwlat_detector/mode # echo hwlat > current_tracer # unshare --fork --pid bash -c 'echo 1 > tracing_on' # dmesg -c Actual behavior: [573502.809060] hwlat_detector: cpumask changed while in round-robin mode, switching to mode none Link: https://lore.kernel.org/linux-trace-kernel/20230316144535.1004952-1-costa.shul@redhat.com Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 0330f7aa8ee63 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Costa Shulyupin <costa.shul@redhat.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-22trace/hwlat: Do not start per-cpu thread if it is already runningTero Kristo
commit 08697bca9bbba15f2058fdbd9f970bd5f6a8a2e8 upstream. The hwlatd tracer will end up starting multiple per-cpu threads with the following script: #!/bin/sh cd /sys/kernel/debug/tracing echo 0 > tracing_on echo hwlat > current_tracer echo per-cpu > hwlat_detector/mode echo 100000 > hwlat_detector/width echo 200000 > hwlat_detector/window echo 1 > tracing_on To fix the issue, check if the hwlatd thread for the cpu is already running, before starting a new one. Along with the previous patch, this avoids running multiple instances of the same CPU thread on the system. Link: https://lore.kernel.org/all/20230302113654.2984709-1-tero.kristo@linux.intel.com/ Link: https://lkml.kernel.org/r/20230310100451.3948583-3-tero.kristo@linux.intel.com Cc: stable@vger.kernel.org Fixes: f46b16520a087 ("trace/hwlat: Implement the per-cpu mode") Signed-off-by: Tero Kristo <tero.kristo@linux.intel.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-22trace/hwlat: Do not wipe the contents of per-cpu thread dataTero Kristo
commit 4c42f5f0d1dd20bddd9f940beb1e6ccad60c4498 upstream. Do not wipe the contents of the per-cpu kthread data when starting the tracer, as this will completely forget about already running instances and can later start new additional per-cpu threads. Link: https://lore.kernel.org/all/20230302113654.2984709-1-tero.kristo@linux.intel.com/ Link: https://lkml.kernel.org/r/20230310100451.3948583-2-tero.kristo@linux.intel.com Cc: stable@vger.kernel.org Fixes: f46b16520a087 ("trace/hwlat: Implement the per-cpu mode") Signed-off-by: Tero Kristo <tero.kristo@linux.intel.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-22ftrace: Fix invalid address access in lookup_rec() when index is 0Chen Zhongjin
commit ee92fa443358f4fc0017c1d0d325c27b37802504 upstream. KASAN reported follow problem: BUG: KASAN: use-after-free in lookup_rec Read of size 8 at addr ffff000199270ff0 by task modprobe CPU: 2 Comm: modprobe Call trace: kasan_report __asan_load8 lookup_rec ftrace_location arch_check_ftrace_location check_kprobe_address_safe register_kprobe When checking pg->records[pg->index - 1].ip in lookup_rec(), it can get a pg which is newly added to ftrace_pages_start in ftrace_process_locs(). Before the first pg->index++, index is 0 and accessing pg->records[-1].ip will cause this problem. Don't check the ip when pg->index is 0. Link: https://lore.kernel.org/linux-trace-kernel/20230309080230.36064-1-chenzhongjin@huawei.com Cc: stable@vger.kernel.org Fixes: 9644302e3315 ("ftrace: Speed up search by skipping pages by address") Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-22tracing: Check field value in hist_field_name()Steven Rostedt (Google)
commit 9f116f76fa8c04c81aef33ad870dbf9a158e5b70 upstream. The function hist_field_name() cannot handle being passed a NULL field parameter. It should never be NULL, but due to a previous bug, NULL was passed to the function and the kernel crashed due to a NULL dereference. Mark Rutland reported this to me on IRC. The bug was fixed, but to prevent future bugs from crashing the kernel, check the field and add a WARN_ON() if it is NULL. Link: https://lkml.kernel.org/r/20230302020810.762384440@goodmis.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Reported-by: Mark Rutland <mark.rutland@arm.com> Fixes: c6afad49d127f ("tracing: Add hist trigger 'sym' and 'sym-offset' modifiers") Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-22tracing: Do not let histogram values have some modifiersSteven Rostedt (Google)
commit e0213434fe3e4a0d118923dc98d31e7ff1cd9e45 upstream. Histogram values can not be strings, stacktraces, graphs, symbols, syscalls, or grouped in buckets or log. Give an error if a value is set to do so. Note, the histogram code was not prepared to handle these modifiers for histograms and caused a bug. Mark Rutland reported: # echo 'p:copy_to_user __arch_copy_to_user n=$arg2' >> /sys/kernel/tracing/kprobe_events # echo 'hist:keys=n:vals=hitcount.buckets=8:sort=hitcount' > /sys/kernel/tracing/events/kprobes/copy_to_user/trigger # cat /sys/kernel/tracing/events/kprobes/copy_to_user/hist [ 143.694628] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 143.695190] Mem abort info: [ 143.695362] ESR = 0x0000000096000004 [ 143.695604] EC = 0x25: DABT (current EL), IL = 32 bits [ 143.695889] SET = 0, FnV = 0 [ 143.696077] EA = 0, S1PTW = 0 [ 143.696302] FSC = 0x04: level 0 translation fault [ 143.702381] Data abort info: [ 143.702614] ISV = 0, ISS = 0x00000004 [ 143.702832] CM = 0, WnR = 0 [ 143.703087] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000448f9000 [ 143.703407] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000 [ 143.704137] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 143.704714] Modules linked in: [ 143.705273] CPU: 0 PID: 133 Comm: cat Not tainted 6.2.0-00003-g6fc512c10a7c #3 [ 143.706138] Hardware name: linux,dummy-virt (DT) [ 143.706723] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 143.707120] pc : hist_field_name.part.0+0x14/0x140 [ 143.707504] lr : hist_field_name.part.0+0x104/0x140 [ 143.707774] sp : ffff800008333a30 [ 143.707952] x29: ffff800008333a30 x28: 0000000000000001 x27: 0000000000400cc0 [ 143.708429] x26: ffffd7a653b20260 x25: 0000000000000000 x24: ffff10d303ee5800 [ 143.708776] x23: ffffd7a6539b27b0 x22: ffff10d303fb8c00 x21: 0000000000000001 [ 143.709127] x20: ffff10d303ec2000 x19: 0000000000000000 x18: 0000000000000000 [ 143.709478] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 143.709824] x14: 0000000000000000 x13: 203a6f666e692072 x12: 6567676972742023 [ 143.710179] x11: 0a230a6d6172676f x10: 000000000000002c x9 : ffffd7a6521e018c [ 143.710584] x8 : 000000000000002c x7 : 7f7f7f7f7f7f7f7f x6 : 000000000000002c [ 143.710915] x5 : ffff10d303b0103e x4 : ffffd7a653b20261 x3 : 000000000000003d [ 143.711239] x2 : 0000000000020001 x1 : 0000000000000001 x0 : 0000000000000000 [ 143.711746] Call trace: [ 143.712115] hist_field_name.part.0+0x14/0x140 [ 143.712642] hist_field_name.part.0+0x104/0x140 [ 143.712925] hist_field_print+0x28/0x140 [ 143.713125] event_hist_trigger_print+0x174/0x4d0 [ 143.713348] hist_show+0xf8/0x980 [ 143.713521] seq_read_iter+0x1bc/0x4b0 [ 143.713711] seq_read+0x8c/0xc4 [ 143.713876] vfs_read+0xc8/0x2a4 [ 143.714043] ksys_read+0x70/0xfc [ 143.714218] __arm64_sys_read+0x24/0x30 [ 143.714400] invoke_syscall+0x50/0x120 [ 143.714587] el0_svc_common.constprop.0+0x4c/0x100 [ 143.714807] do_el0_svc+0x44/0xd0 [ 143.714970] el0_svc+0x2c/0x84 [ 143.715134] el0t_64_sync_handler+0xbc/0x140 [ 143.715334] el0t_64_sync+0x190/0x194 [ 143.715742] Code: a9bd7bfd 910003fd a90153f3 aa0003f3 (f9400000) [ 143.716510] ---[ end trace 0000000000000000 ]--- Segmentation fault Link: https://lkml.kernel.org/r/20230302020810.559462599@goodmis.org Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Fixes: c6afad49d127f ("tracing: Add hist trigger 'sym' and 'sym-offset' modifiers") Reported-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-22tracing: Make splice_read available againSung-hun Kim
commit e400be674a1a40e9dcb2e95f84d6c1fd2d88f31d upstream. Since the commit 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") is applied to the kernel, splice() and sendfile() calls on the trace file (/sys/kernel/debug/tracing /trace) return EINVAL. This patch restores these system calls by initializing splice_read in file_operations of the trace file. This patch only enables such functionalities for the read case. Link: https://lore.kernel.org/linux-trace-kernel/20230314013707.28814-1-sfoon.kim@samsung.com Cc: stable@vger.kernel.org Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") Signed-off-by: Sung-hun Kim <sfoon.kim@samsung.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11tracing: Add NULL checks for buffer in ring_buffer_free_read_page()Jia-Ju Bai
[ Upstream commit 3e4272b9954094907f16861199728f14002fcaf6 ] In a previous commit 7433632c9ff6, buffer, buffer->buffers and buffer->buffers[cpu] in ring_buffer_wake_waiters() can be NULL, and thus the related checks are added. However, in the same call stack, these variables are also used in ring_buffer_free_read_page(): tracing_buffers_release() ring_buffer_wake_waiters(iter->array_buffer->buffer) cpu_buffer = buffer->buffers[cpu] -> Add checks by previous commit ring_buffer_free_read_page(iter->array_buffer->buffer) cpu_buffer = buffer->buffers[cpu] -> No check Thus, to avod possible null-pointer derefernces, the related checks should be added. These results are reported by a static tool designed by myself. Link: https://lkml.kernel.org/r/20230113125501.760324-1-baijiaju1990@gmail.com Reported-by: TOTE Robot <oslab@tsinghua.edu.cn> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10tracing/eprobe: Fix to add filter on eprobe description in README fileMasami Hiramatsu (Google)
commit 133921530c42960c07d25d12677f9e131a2b0cdf upstream. Fix to add a description of the filter on eprobe in README file. This is required to identify the kernel supports the filter on eprobe or not. Link: https://lore.kernel.org/all/167309833728.640500.12232259238201433587.stgit@devnote3/ Fixes: 752be5c5c910 ("tracing/eprobe: Add eprobe filter support") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10ring-buffer: Handle race between rb_move_tail and rb_check_pagesMukesh Ojha
commit 8843e06f67b14f71c044bf6267b2387784c7e198 upstream. It seems a data race between ring_buffer writing and integrity check. That is, RB_FLAG of head_page is been updating, while at same time RB_FLAG was cleared when doing integrity check rb_check_pages(): rb_check_pages() rb_handle_head_page(): -------- -------- rb_head_page_deactivate() rb_head_page_set_normal() rb_head_page_activate() We do intergrity test of the list to check if the list is corrupted and it is still worth doing it. So, let's refactor rb_check_pages() such that we no longer clear and set flag during the list sanity checking. [1] and [2] are the test to reproduce and the crash report respectively. 1: ``` read_trace.sh while true; do # the "trace" file is closed after read head -1 /sys/kernel/tracing/trace > /dev/null done ``` ``` repro.sh sysctl -w kernel.panic_on_warn=1 # function tracer will writing enough data into ring_buffer echo function > /sys/kernel/tracing/current_tracer ./read_trace.sh & ./read_trace.sh & ./read_trace.sh & ./read_trace.sh & ./read_trace.sh & ./read_trace.sh & ./read_trace.sh & ./read_trace.sh & ``` 2: ------------[ cut here ]------------ WARNING: CPU: 9 PID: 62 at kernel/trace/ring_buffer.c:2653 rb_move_tail+0x450/0x470 Modules linked in: CPU: 9 PID: 62 Comm: ksoftirqd/9 Tainted: G W 6.2.0-rc6+ Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 RIP: 0010:rb_move_tail+0x450/0x470 Code: ff ff 4c 89 c8 f0 4d 0f b1 02 48 89 c2 48 83 e2 fc 49 39 d0 75 24 83 e0 03 83 f8 02 0f 84 e1 fb ff ff 48 8b 57 10 f0 ff 42 08 <0f> 0b 83 f8 02 0f 84 ce fb ff ff e9 db RSP: 0018:ffffb5564089bd00 EFLAGS: 00000203 RAX: 0000000000000000 RBX: ffff9db385a2bf81 RCX: ffffb5564089bd18 RDX: ffff9db281110100 RSI: 0000000000000fe4 RDI: ffff9db380145400 RBP: ffff9db385a2bf80 R08: ffff9db385a2bfc0 R09: ffff9db385a2bfc2 R10: ffff9db385a6c000 R11: ffff9db385a2bf80 R12: 0000000000000000 R13: 00000000000003e8 R14: ffff9db281110100 R15: ffffffffbb006108 FS: 0000000000000000(0000) GS:ffff9db3bdcc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005602323024c8 CR3: 0000000022e0c000 CR4: 00000000000006e0 Call Trace: <TASK> ring_buffer_lock_reserve+0x136/0x360 ? __do_softirq+0x287/0x2df ? __pfx_rcu_softirq_qs+0x10/0x10 trace_function+0x21/0x110 ? __pfx_rcu_softirq_qs+0x10/0x10 ? __do_softirq+0x287/0x2df function_trace_call+0xf6/0x120 0xffffffffc038f097 ? rcu_softirq_qs+0x5/0x140 rcu_softirq_qs+0x5/0x140 __do_softirq+0x287/0x2df run_ksoftirqd+0x2a/0x30 smpboot_thread_fn+0x188/0x220 ? __pfx_smpboot_thread_fn+0x10/0x10 kthread+0xe7/0x110 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2c/0x50 </TASK> ---[ end trace 0000000000000000 ]--- [ crash report and test reproducer credit goes to Zheng Yejian] Link: https://lore.kernel.org/linux-trace-kernel/1676376403-16462-1-git-send-email-quic_mojha@quicinc.com Cc: <mhiramat@kernel.org> Cc: stable@vger.kernel.org Fixes: 1039221cc278 ("ring-buffer: Do not disable recording when there is an iterator") Reported-by: Zheng Yejian <zhengyejian1@huawei.com> Signed-off-by: Mukesh Ojha <quic_mojha@quicinc.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10trace/blktrace: fix memory leak with using debugfs_lookup()Greg Kroah-Hartman
[ Upstream commit 83e8864fee26f63a7435e941b7c36a20fd6fe93e ] When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: Jens Axboe <axboe@kernel.dk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-kernel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20230202141956.2299521-1-gregkh@linuxfoundation.org Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-15Merge tag 'trace-v6.2-rc7-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixlet from Steven Rostedt: "Make trace_define_field_ext() static. Just after the fix to TASK_COMM_LEN not converted to its value in trace_events was pulled, the kernel test robot reported that the helper function trace_define_field_ext() added to that change was only used in the file it was defined in but was not declared static. Make it a local function" * tag 'trace-v6.2-rc7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Make trace_define_field_ext() static
2023-02-12tracing: Make trace_define_field_ext() staticSteven Rostedt (Google)
trace_define_field_ext() is not used outside of trace_events.c, it should be static. Link: https://lore.kernel.org/oe-kbuild-all/202302130750.679RaRog-lkp@intel.com/ Fixes: b6c7abd1c28a ("tracing: Fix TASK_COMM_LEN in trace event format file") Reported-by: Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-12Merge tag 'trace-v6.2-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fix from Steven Rostedt: "Fix showing of TASK_COMM_LEN instead of its value The TASK_COMM_LEN was converted from a macro into an enum so that BTF would have access to it. But this unfortunately caused TASK_COMM_LEN to display in the format fields of trace events, as they are created by the TRACE_EVENT() macro and such, macros convert to their values, where as enums do not. To handle this, instead of using the field itself to be display, save the value of the array size as another field in the trace_event_fields structure, and use that instead. Not only does this fix the issue, but also converts the other trace events that have this same problem (but were not breaking tooling). With this change, the original work around b3bc8547d3be6 ("tracing: Have TRACE_DEFINE_ENUM affect trace event types as well") could be reverted (but that should be done in the merge window)" * tag 'trace-v6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Fix TASK_COMM_LEN in trace event format file
2023-02-12tracing: Fix TASK_COMM_LEN in trace event format fileYafang Shao
After commit 3087c61ed2c4 ("tools/testing/selftests/bpf: replace open-coded 16 with TASK_COMM_LEN"), the content of the format file under /sys/kernel/tracing/events/task/task_newtask was changed from field:char comm[16]; offset:12; size:16; signed:0; to field:char comm[TASK_COMM_LEN]; offset:12; size:16; signed:0; John reported that this change breaks older versions of perfetto. Then Mathieu pointed out that this behavioral change was caused by the use of __stringify(_len), which happens to work on macros, but not on enum labels. And he also gave the suggestion on how to fix it: :One possible solution to make this more robust would be to extend :struct trace_event_fields with one more field that indicates the length :of an array as an actual integer, without storing it in its stringified :form in the type, and do the formatting in f_show where it belongs. The result as follows after this change, $ cat /sys/kernel/tracing/events/task/task_newtask/format field:char comm[16]; offset:12; size:16; signed:0; Link: https://lore.kernel.org/lkml/Y+QaZtz55LIirsUO@google.com/ Link: https://lore.kernel.org/linux-trace-kernel/20230210155921.4610-1-laoar.shao@gmail.com/ Link: https://lore.kernel.org/linux-trace-kernel/20230212151303.12353-1-laoar.shao@gmail.com Cc: stable@vger.kernel.org Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Kajetan Puchalski <kajetan.puchalski@arm.com> CC: Qais Yousef <qyousef@layalina.io> Fixes: 3087c61ed2c4 ("tools/testing/selftests/bpf: replace open-coded 16 with TASK_COMM_LEN") Reported-by: John Stultz <jstultz@google.com> Debugged-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-07Merge tag 'trace-v6.2-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fix from Steven Rostedt: "Fix regression in poll() and select() With the fix that made poll() and select() block if read would block caused a slight regression in rasdaemon, as it needed that kind of behavior. Add a way to make that behavior come back by writing zero into the 'buffer_percentage', which means to never block on read" * tag 'trace-v6.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing: Fix poll() and select() do not work on per_cpu trace_pipe and trace_pipe_raw
2023-02-02Merge tag 'net-6.2-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from bpf, can and netfilter. Current release - regressions: - phy: fix null-deref in phy_attach_direct - mac802154: fix possible double free upon parsing error Previous releases - regressions: - bpf: preserve reg parent/live fields when copying range info, prevent mis-verification of programs as safe - ip6: fix GRE tunnels not generating IPv6 link local addresses - phy: dp83822: fix null-deref on DP83825/DP83826 devices - sctp: do not check hb_timer.expires when resetting hb_timer - eth: mtk_sock: fix SGMII configuration after phylink conversion Previous releases - always broken: - eth: xdp: execute xdp_do_flush() before napi_complete_done() - skb: do not mix page pool and page referenced frags in GRO - bpf: - fix a possible task gone issue with bpf_send_signal[_thread]() - fix an off-by-one bug in bpf_mem_cache_idx() to select the right cache - add missing btf_put to register_btf_id_dtor_kfuncs - sockmap: fon't let sock_map_{close,destroy,unhash} call itself - gso: fix null-deref in skb_segment_list() - mctp: purge receive queues on sk destruction - fix UaF caused by accept on already connected socket in exotic socket families - tls: don't treat list head as an entry in tls_is_tx_ready() - netfilter: br_netfilter: disable sabotage_in hook after first suppression - wwan: t7xx: fix runtime PM implementation Misc: - MAINTAINERS: spring cleanup of networking maintainers" * tag 'net-6.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (65 commits) mtk_sgmii: enable PCS polling to allow SFP work net: mediatek: sgmii: fix duplex configuration net: mediatek: sgmii: ensure the SGMII PHY is powered down on configuration MAINTAINERS: update SCTP maintainers MAINTAINERS: ipv6: retire Hideaki Yoshifuji mailmap: add John Crispin's entry MAINTAINERS: bonding: move Veaceslav Falico to CREDITS net: openvswitch: fix flow memory leak in ovs_flow_cmd_new net: ethernet: mtk_eth_soc: disable hardware DSA untagging for second MAC virtio-net: Keep stop() to follow mirror sequence of open() selftests: net: udpgso_bench_tx: Cater for pending datagrams zerocopy benchmarking selftests: net: udpgso_bench: Fix racing bug between the rx/tx programs selftests: net: udpgso_bench_rx/tx: Stop when wrong CLI args are provided selftests: net: udpgso_bench_rx: Fix 'used uninitialized' compiler warning can: mcp251xfd: mcp251xfd_ring_set_ringparam(): assign missing tx_obj_num_coalesce_irq can: isotp: split tx timer into transmission and timeout can: isotp: handle wait_event_interruptible() return values can: raw: fix CAN FD frame transmissions over CAN XL devices can: j1939: fix errant WARN_ON_ONCE in j1939_session_deactivate hv_netvsc: Fix missed pagebuf entries in netvsc_dma_map/unmap() ...
2023-02-02tracing: Fix poll() and select() do not work on per_cpu trace_pipe and ↵Shiju Jose
trace_pipe_raw poll() and select() on per_cpu trace_pipe and trace_pipe_raw do not work since kernel 6.1-rc6. This issue is seen after the commit 42fb0a1e84ff525ebe560e2baf9451ab69127e2b ("tracing/ring-buffer: Have polling block on watermark"). This issue is firstly detected and reported, when testing the CXL error events in the rasdaemon and also erified using the test application for poll() and select(). This issue occurs for the per_cpu case, when calling the ring_buffer_poll_wait(), in kernel/trace/ring_buffer.c, with the buffer_percent > 0 and then wait until the percentage of pages are available. The default value set for the buffer_percent is 50 in the kernel/trace/trace.c. As a fix, allow userspace application could set buffer_percent as 0 through the buffer_percent_fops, so that the task will wake up as soon as data is added to any of the specific cpu buffer. Link: https://lore.kernel.org/linux-trace-kernel/20230202182309.742-2-shiju.jose@huawei.com Cc: <mhiramat@kernel.org> Cc: <mchehab@kernel.org> Cc: <linux-edac@vger.kernel.org> Cc: stable@vger.kernel.org Fixes: 42fb0a1e84ff5 ("tracing/ring-buffer: Have polling block on watermark") Signed-off-by: Shiju Jose <shiju.jose@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-25rv: remove redundant initialization of pointer ptrColin Ian King
The pointer ptr is being initialized with a value that is never read, it is being updated later on a call to strim. Remove the extraneous initialization. Link: https://lkml.kernel.org/r/20230116161612.77192-1-colin.i.king@gmail.com Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-25tracing/filter: fix kernel-doc warningsRandy Dunlap
Use the 'struct' keyword for a struct's kernel-doc notation and use the correct function parameter name to eliminate kernel-doc warnings: kernel/trace/trace_events_filter.c:136: warning: cannot understand function prototype: 'struct prog_entry ' kerne/trace/trace_events_filter.c:155: warning: Excess function parameter 'when_to_branch' description in 'update_preds' Also correct some trivial punctuation problems. Link: https://lkml.kernel.org/r/20230108021238.16398-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-24trace_events_hist: add check for return value of 'create_hist_field'Natalia Petrova
Function 'create_hist_field' is called recursively at trace_events_hist.c:1954 and can return NULL-value that's why we have to check it to avoid null pointer dereference. Found by Linux Verification Center (linuxtesting.org) with SVACE. Link: https://lkml.kernel.org/r/20230111120409.4111-1-n.petrova@fintech.ru Cc: stable@vger.kernel.org Fixes: 30350d65ac56 ("tracing: Add variable support to hist triggers") Signed-off-by: Natalia Petrova <n.petrova@fintech.ru> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-24tracing/osnoise: Use built-in RCU list checkingChuang Wang
list_for_each_entry_rcu() has built-in RCU and lock checking. Pass cond argument to list_for_each_entry_rcu() to silence false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled. Execute as follow: [tracing]# echo osnoise > current_tracer [tracing]# echo 1 > tracing_on [tracing]# echo 0 > tracing_on The trace_types_lock is held when osnoise_tracer_stop() or timerlat_tracer_stop() are called in the non-RCU read side section. So, pass lockdep_is_held(&trace_types_lock) to silence false lockdep warning. Link: https://lkml.kernel.org/r/20221227023036.784337-1-nashuiliang@gmail.com Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: dae181349f1e ("tracing/osnoise: Support a list of trace_array *tr") Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Chuang Wang <nashuiliang@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-24tracing: Kconfig: Fix spelling/grammar/punctuationRandy Dunlap
Fix some editorial nits in trace Kconfig. Link: https://lkml.kernel.org/r/20230124181647.15902-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-24tracing: Make sure trace_printk() can output as soon as it can be usedSteven Rostedt (Google)
Currently trace_printk() can be used as soon as early_trace_init() is called from start_kernel(). But if a crash happens, and "ftrace_dump_on_oops" is set on the kernel command line, all you get will be: [ 0.456075] <idle>-0 0dN.2. 347519us : Unknown type 6 [ 0.456075] <idle>-0 0dN.2. 353141us : Unknown type 6 [ 0.456075] <idle>-0 0dN.2. 358684us : Unknown type 6 This is because the trace_printk() event (type 6) hasn't been registered yet. That gets done via an early_initcall(), which may be early, but not early enough. Instead of registering the trace_printk() event (and other ftrace events, which are not trace events) via an early_initcall(), have them registered at the same time that trace_printk() can be used. This way, if there is a crash before early_initcall(), then the trace_printk()s will actually be useful. Link: https://lkml.kernel.org/r/20230104161412.019f6c55@gandalf.local.home Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: e725c731e3bb1 ("tracing: Split tracing initialization into two for early initialization") Reported-by: "Joel Fernandes (Google)" <joel@joelfernandes.org> Tested-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-24ftrace: Export ftrace_free_filter() to modulesMark Rutland
Setting filters on an ftrace ops results in some memory being allocated for the filter hashes, which must be freed before the ops can be freed. This can be done by removing every individual element of the hash by calling ftrace_set_filter_ip() or ftrace_set_filter_ips() with `remove` set, but this is somewhat error prone as it's easy to forget to remove an element. Make it easier to clean this up by exporting ftrace_free_filter(), which can be used to clean up all of the filter hashes after an ftrace_ops has been unregistered. Using this, fix the ftrace-direct* samples to free hashes prior to being unloaded. All other code either removes individual filters explicitly or is built-in and already calls ftrace_free_filter(). Link: https://lkml.kernel.org/r/20230103124912.2948963-3-mark.rutland@arm.com Cc: stable@vger.kernel.org Cc: Florent Revest <revest@chromium.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Fixes: e1067a07cfbc ("ftrace/samples: Add module to test multi direct modify interface") Fixes: 5fae941b9a6f ("ftrace/samples: Add multi direct interface test module") Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-18bpf: Fix a possible task gone issue with bpf_send_signal[_thread]() helpersYonghong Song
In current bpf_send_signal() and bpf_send_signal_thread() helper implementation, irq_work is used to handle nmi context. Hao Sun reported in [1] that the current task at the entry of the helper might be gone during irq_work callback processing. To fix the issue, a reference is acquired for the current task before enqueuing into the irq_work so that the queued task is still available during irq_work callback processing. [1] https://lore.kernel.org/bpf/20230109074425.12556-1-sunhao.th@gmail.com/ Fixes: 8b401f9ed244 ("bpf: implement bpf_send_signal() helper") Tested-by: Hao Sun <sunhao.th@gmail.com> Reported-by: Hao Sun <sunhao.th@gmail.com> Signed-off-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/r/20230118204815.3331855-1-yhs@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-01-06bpf: Skip task with pid=1 in send_signal_common()Hao Sun
The following kernel panic can be triggered when a task with pid=1 attaches a prog that attempts to send killing signal to itself, also see [1] for more details: Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b CPU: 3 PID: 1 Comm: systemd Not tainted 6.1.0-09652-g59fe41b5255f #148 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x100/0x178 lib/dump_stack.c:106 panic+0x2c4/0x60f kernel/panic.c:275 do_exit.cold+0x63/0xe4 kernel/exit.c:789 do_group_exit+0xd4/0x2a0 kernel/exit.c:950 get_signal+0x2460/0x2600 kernel/signal.c:2858 arch_do_signal_or_restart+0x78/0x5d0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd So skip task with pid=1 in bpf_send_signal_common() to avoid the panic. [1] https://lore.kernel.org/bpf/20221222043507.33037-1-sunhao.th@gmail.com Signed-off-by: Hao Sun <sunhao.th@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20230106084838.12690-1-sunhao.th@gmail.com
2022-12-21Merge tag 'trace-v6.2-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fix from Steven Rostedt: "I missed this minor hardening of the kernel in the first pull. - Make monitor structures read only" * tag 'trace-v6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: rv/monitors: Move monitor structure in rodata
2022-12-21Merge tag 'trace-probes-v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull trace probes updates from Steven Rostedt: - New "symstr" type for dynamic events that writes the name of the function+offset into the ring buffer and not just the address - Prevent kernel symbol processing on addresses in user space probes (uprobes). - And minor fixes and clean ups * tag 'trace-probes-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Reject symbol/symstr type for uprobe tracing/probes: Add symstr type for dynamic events kprobes: kretprobe events missing on 2-core KVM guest kprobes: Fix check for probe enabled in kill_kprobe() test_kprobes: Fix implicit declaration error of test_kprobes tracing: Fix race where eprobes can be called before the event
2022-12-20rv/monitors: Move monitor structure in rodataAlessandro Carminati
It makes sense to move the important monitor structure into rodata to prevent accidental structure modification. Link: https://lkml.kernel.org/r/20221122173648.4732-1-acarmina@redhat.com Signed-off-by: Alessandro Carminati <acarmina@redhat.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-12-19Merge tag 'powerpc-6.2-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Add powerpc qspinlock implementation optimised for large system scalability and paravirt. See the merge message for more details - Enable objtool to be built on powerpc to generate mcount locations - Use a temporary mm for code patching with the Radix MMU, so the writable mapping is restricted to the patching CPU - Add an option to build the 64-bit big-endian kernel with the ELFv2 ABI - Sanitise user registers on interrupt entry on 64-bit Book3S - Many other small features and fixes Thanks to Aboorva Devarajan, Angel Iglesias, Benjamin Gray, Bjorn Helgaas, Bo Liu, Chen Lifu, Christoph Hellwig, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Deming Wang, Disha Goel, Dmitry Torokhov, Finn Thain, Geert Uytterhoeven, Gustavo A. R. Silva, Haowen Bai, Joel Stanley, Jordan Niethe, Julia Lawall, Kajol Jain, Laurent Dufour, Li zeming, Miaoqian Lin, Michael Jeanson, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Miehlbradt, Nicholas Piggin, Pali Rohár, Randy Dunlap, Rohan McLure, Russell Currey, Sathvika Vasireddy, Shaomin Deng, Stephen Kitt, Stephen Rothwell, Thomas Weißschuh, Tiezhu Yang, Uwe Kleine-König, Xie Shaowen, Xiu Jianfeng, XueBing Chen, Yang Yingliang, Zhang Jiaming, ruanjinjie, Jessica Yu, and Wolfram Sang. * tag 'powerpc-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (181 commits) powerpc/code-patching: Fix oops with DEBUG_VM enabled powerpc/qspinlock: Fix 32-bit build powerpc/prom: Fix 32-bit build powerpc/rtas: mandate RTAS syscall filtering powerpc/rtas: define pr_fmt and convert printk call sites powerpc/rtas: clean up includes powerpc/rtas: clean up rtas_error_log_max initialization powerpc/pseries/eeh: use correct API for error log size powerpc/rtas: avoid scheduling in rtas_os_term() powerpc/rtas: avoid device tree lookups in rtas_os_term() powerpc/rtasd: use correct OF API for event scan rate powerpc/rtas: document rtas_call() powerpc/pseries: unregister VPA when hot unplugging a CPU powerpc/pseries: reset the RCU watchdogs after a LPM powerpc: Take in account addition CPU node when building kexec FDT powerpc: export the CPU node count powerpc/cpuidle: Set CPUIDLE_FLAG_POLLING for snooze state powerpc/dts/fsl: Fix pca954x i2c-mux node names cxl: Remove unnecessary cxl_pci_window_alignment() selftests/powerpc: Fix resource leaks ...
2022-12-15Merge tag 'trace-v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - Add options to the osnoise tracer: - 'panic_on_stop' option that panics the kernel if osnoise is greater than some user defined threshold. - 'preempt' option, to test noise while preemption is disabled - 'irq' option, to test noise when interrupts are disabled - Add .percent and .graph suffix to histograms to give different outputs - Add nohitcount to disable showing hitcount in histogram output - Add new __cpumask() to trace event fields to annotate that a unsigned long array is a cpumask to user space and should be treated as one. - Add trace_trigger kernel command line parameter to enable trace event triggers at boot up. Useful to trace stack traces, disable tracing and take snapshots. - Fix x86/kmmio mmio tracer to work with the updates to lockdep - Unify the panic and die notifiers - Add back ftrace_expect reference that is used to extract more information in the ftrace_bug() code. - Have trigger filter parsing errors show up in the tracing error log. - Updated MAINTAINERS file to add kernel tracing mailing list and patchwork info - Use IDA to keep track of event type numbers. - And minor fixes and clean ups * tag 'trace-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (44 commits) tracing: Fix cpumask() example typo tracing: Improve panic/die notifiers ftrace: Prevent RCU stall on PREEMPT_VOLUNTARY kernels tracing: Do not synchronize freeing of trigger filter on boot up tracing: Remove pointer (asterisk) and brackets from cpumask_t field tracing: Have trigger filter parsing errors show up in error_log x86/mm/kmmio: Remove redundant preempt_disable() tracing: Fix infinite loop in tracing_read_pipe on overflowed print_trace_line Documentation/osnoise: Add osnoise/options documentation tracing/osnoise: Add preempt and/or irq disabled options tracing/osnoise: Add PANIC_ON_STOP option Documentation/osnoise: Escape underscore of NO_ prefix tracing: Fix some checker warnings tracing/osnoise: Make osnoise_options static tracing: remove unnecessary trace_trigger ifdef ring-buffer: Handle resize in early boot up tracing/hist: Fix issue of losting command info in error_log tracing: Fix issue of missing one synthetic field tracing/hist: Fix out-of-bound write on 'action_data.var_ref_idx' tracing/hist: Fix wrong return value in parse_action_params() ...
2022-12-15tracing/probes: Reject symbol/symstr type for uprobeMasami Hiramatsu (Google)
Since uprobe's argument must contain the user-space data, that should not be converted to kernel symbols. Reject if user specifies these types on uprobe events. e.g. /sys/kernel/debug/tracing # echo 'p /bin/sh:10 %ax:symbol' >> uprobe_events sh: write error: Invalid argument /sys/kernel/debug/tracing # echo 'p /bin/sh:10 %ax:symstr' >> uprobe_events sh: write error: Invalid argument /sys/kernel/debug/tracing # cat error_log [ 1783.134883] trace_uprobe: error: Unknown type is specified Command: p /bin/sh:10 %ax:symbol ^ [ 1792.201120] trace_uprobe: error: Unknown type is specified Command: p /bin/sh:10 %ax:symstr ^ Link: https://lore.kernel.org/all/166679931679.1528100.15540755370726009882.stgit@devnote3/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-12-15tracing/probes: Add symstr type for dynamic eventsMasami Hiramatsu (Google)
Add 'symstr' type for storing the kernel symbol as a string data instead of the symbol address. This allows us to filter the events by wildcard symbol name. e.g. # echo 'e:wqfunc workqueue.workqueue_execute_start symname=$function:symstr' >> dynamic_events # cat events/eprobes/wqfunc/format name: wqfunc ID: 2110 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:__data_loc char[] symname; offset:8; size:4; signed:1; print fmt: " symname=\"%s\"", __get_str(symname) Note that there is already 'symbol' type which just change the print format (so it still stores the symbol address in the tracing ring buffer.) On the other hand, 'symstr' type stores the actual "symbol+offset/size" data as a string. Link: https://lore.kernel.org/all/166679930847.1528100.4124308529180235965.stgit@devnote3/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-12-14Merge tag 'x86_core_for_v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Borislav Petkov: - Add the call depth tracking mitigation for Retbleed which has been long in the making. It is a lighterweight software-only fix for Skylake-based cores where enabling IBRS is a big hammer and causes a significant performance impact. What it basically does is, it aligns all kernel functions to 16 bytes boundary and adds a 16-byte padding before the function, objtool collects all functions' locations and when the mitigation gets applied, it patches a call accounting thunk which is used to track the call depth of the stack at any time. When that call depth reaches a magical, microarchitecture-specific value for the Return Stack Buffer, the code stuffs that RSB and avoids its underflow which could otherwise lead to the Intel variant of Retbleed. This software-only solution brings a lot of the lost performance back, as benchmarks suggest: https://lore.kernel.org/all/20220915111039.092790446@infradead.org/ That page above also contains a lot more detailed explanation of the whole mechanism - Implement a new control flow integrity scheme called FineIBT which is based on the software kCFI implementation and uses hardware IBT support where present to annotate and track indirect branches using a hash to validate them - Other misc fixes and cleanups * tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits) x86/paravirt: Use common macro for creating simple asm paravirt functions x86/paravirt: Remove clobber bitmask from .parainstructions x86/debug: Include percpu.h in debugreg.h to get DECLARE_PER_CPU() et al x86/cpufeatures: Move X86_FEATURE_CALL_DEPTH from bit 18 to bit 19 of word 11, to leave space for WIP X86_FEATURE_SGX_EDECCSSA bit x86/Kconfig: Enable kernel IBT by default x86,pm: Force out-of-line memcpy() objtool: Fix weak hole vs prefix symbol objtool: Optimize elf_dirty_reloc_sym() x86/cfi: Add boot time hash randomization x86/cfi: Boot time selection of CFI scheme x86/ibt: Implement FineIBT objtool: Add --cfi to generate the .cfi_sites section x86: Add prefix symbols for function padding objtool: Add option to generate prefix symbols objtool: Avoid O(bloody terrible) behaviour -- an ode to libelf objtool: Slice up elf_create_section_symbol() kallsyms: Revert "Take callthunks into account" x86: Unconfuse CONFIG_ and X86_FEATURE_ namespaces x86/retpoline: Fix crash printing warning x86/paravirt: Fix a !PARAVIRT build warning ...
2022-12-14tracing: Improve panic/die notifiersGuilherme G. Piccoli
Currently the tracing dump_on_oops feature is implemented through separate notifiers, one for die/oops and the other for panic; given they have the same functionality, let's unify them. Also improve the function comment and change the priority of the notifier to make it execute earlier, avoiding showing useless trace data (like the callback names for the other notifiers); finally, we also removed an unnecessary header inclusion. Link: https://lkml.kernel.org/r/20220819221731.480795-7-gpiccoli@igalia.com Cc: Petr Mladek <pmladek@suse.com> Cc: Sergei Shtylyov <sergei.shtylyov@gmail.com> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>