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2021-11-17ftrace: do CPU checking after preemption disabled王贇
[ Upstream commit d33cc657372366a8959f099c619a208b4c5dc664 ] With CONFIG_DEBUG_PREEMPT we observed reports like: BUG: using smp_processor_id() in preemptible caller is perf_ftrace_function_call+0x6f/0x2e0 CPU: 1 PID: 680 Comm: a.out Not tainted Call Trace: <TASK> dump_stack_lvl+0x8d/0xcf check_preemption_disabled+0x104/0x110 ? optimize_nops.isra.7+0x230/0x230 ? text_poke_bp_batch+0x9f/0x310 perf_ftrace_function_call+0x6f/0x2e0 ... __text_poke+0x5/0x620 text_poke_bp_batch+0x9f/0x310 This telling us the CPU could be changed after task is preempted, and the checking on CPU before preemption will be invalid. Since now ftrace_test_recursion_trylock() will help to disable the preemption, this patch just do the checking after trylock() to address the issue. Link: https://lkml.kernel.org/r/54880691-5fe2-33e7-d12f-1fa6136f5183@linux.alibaba.com CC: Steven Rostedt <rostedt@goodmis.org> Cc: Guo Ren <guoren@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Petr Mladek <pmladek@suse.com> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Jisheng Zhang <jszhang@kernel.org> Reported-by: Abaci <abaci@linux.alibaba.com> Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-17tracing/cfi: Fix cmp_entries_* functions signature mismatchKalesh Singh
[ Upstream commit 7ce1bb83a14019f8c396d57ec704d19478747716 ] If CONFIG_CFI_CLANG=y, attempting to read an event histogram will cause the kernel to panic due to failed CFI check. 1. echo 'hist:keys=common_pid' >> events/sched/sched_switch/trigger 2. cat events/sched/sched_switch/hist 3. kernel panics on attempting to read hist This happens because the sort() function expects a generic int (*)(const void *, const void *) pointer for the compare function. To prevent this CFI failure, change tracing map cmp_entries_* function signatures to match this. Also, fix the build error reported by the kernel test robot [1]. [1] https://lore.kernel.org/r/202110141140.zzi4dRh4-lkp@intel.com/ Link: https://lkml.kernel.org/r/20211014045217.3265162-1-kaleshsingh@google.com Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-17tracing: Disable "other" permission bits in the tracefs filesSteven Rostedt (VMware)
[ Upstream commit 21ccc9cd72116289469e5519b6159c675a2fa58f ] When building the files in the tracefs file system, do not by default set any permissions for OTH (other). This will make it easier for admins who want to define a group for accessing tracefs and not having to first disable all the permission bits for "other" in the file system. As tracing can leak sensitive information, it should never by default allowing all users access. An admin can still set the permission bits for others to have access, which may be useful for creating a honeypot and seeing who takes advantage of it and roots the machine. Link: https://lkml.kernel.org/r/20210818153038.864149276@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-17ring-buffer: Protect ring_buffer_reset() from reentrancySteven Rostedt (VMware)
commit 51d157946666382e779f94c39891e8e9a020da78 upstream. The resetting of the entire ring buffer use to simply go through and reset each individual CPU buffer that had its own protection and synchronization. But this was very slow, due to performing a synchronization for each CPU. The code was reshuffled to do one disabling of all CPU buffers, followed by a single RCU synchronization, and then the resetting of each of the CPU buffers. But unfortunately, the mutex that prevented multiple occurrences of resetting the buffer was not moved to the upper function, and there is nothing to protect from it. Take the ring buffer mutex around the global reset. Cc: stable@vger.kernel.org Fixes: b23d7a5f4a07a ("ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU") Reported-by: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-27tracing: Have all levels of checks prevent recursionSteven Rostedt (VMware)
commit ed65df63a39a3f6ed04f7258de8b6789e5021c18 upstream. While writing an email explaining the "bit = 0" logic for a discussion on making ftrace_test_recursion_trylock() disable preemption, I discovered a path that makes the "not do the logic if bit is zero" unsafe. The recursion logic is done in hot paths like the function tracer. Thus, any code executed causes noticeable overhead. Thus, tricks are done to try to limit the amount of code executed. This included the recursion testing logic. Having recursion testing is important, as there are many paths that can end up in an infinite recursion cycle when tracing every function in the kernel. Thus protection is needed to prevent that from happening. Because it is OK to recurse due to different running context levels (e.g. an interrupt preempts a trace, and then a trace occurs in the interrupt handler), a set of bits are used to know which context one is in (normal, softirq, irq and NMI). If a recursion occurs in the same level, it is prevented*. Then there are infrastructure levels of recursion as well. When more than one callback is attached to the same function to trace, it calls a loop function to iterate over all the callbacks. Both the callbacks and the loop function have recursion protection. The callbacks use the "ftrace_test_recursion_trylock()" which has a "function" set of context bits to test, and the loop function calls the internal trace_test_and_set_recursion() directly, with an "internal" set of bits. If an architecture does not implement all the features supported by ftrace then the callbacks are never called directly, and the loop function is called instead, which will implement the features of ftrace. Since both the loop function and the callbacks do recursion protection, it was seemed unnecessary to do it in both locations. Thus, a trick was made to have the internal set of recursion bits at a more significant bit location than the function bits. Then, if any of the higher bits were set, the logic of the function bits could be skipped, as any new recursion would first have to go through the loop function. This is true for architectures that do not support all the ftrace features, because all functions being traced must first go through the loop function before going to the callbacks. But this is not true for architectures that support all the ftrace features. That's because the loop function could be called due to two callbacks attached to the same function, but then a recursion function inside the callback could be called that does not share any other callback, and it will be called directly. i.e. traced_function_1: [ more than one callback tracing it ] call loop_func loop_func: trace_recursion set internal bit call callback callback: trace_recursion [ skipped because internal bit is set, return 0 ] call traced_function_2 traced_function_2: [ only traced by above callback ] call callback callback: trace_recursion [ skipped because internal bit is set, return 0 ] call traced_function_2 [ wash, rinse, repeat, BOOM! out of shampoo! ] Thus, the "bit == 0 skip" trick is not safe, unless the loop function is call for all functions. Since we want to encourage architectures to implement all ftrace features, having them slow down due to this extra logic may encourage the maintainers to update to the latest ftrace features. And because this logic is only safe for them, remove it completely. [*] There is on layer of recursion that is allowed, and that is to allow for the transition between interrupt context (normal -> softirq -> irq -> NMI), because a trace may occur before the context update is visible to the trace recursion logic. Link: https://lore.kernel.org/all/609b565a-ed6e-a1da-f025-166691b5d994@linux.alibaba.com/ Link: https://lkml.kernel.org/r/20211018154412.09fcad3c@gandalf.local.home Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@hansenpartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Jisheng Zhang <jszhang@kernel.org> Cc: =?utf-8?b?546L6LSH?= <yun.wang@linux.alibaba.com> Cc: Guo Ren <guoren@kernel.org> Cc: stable@vger.kernel.org Fixes: edc15cafcbfa3 ("tracing: Avoid unnecessary multiple recursion checks") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-20tracing: Fix missing osnoise tracer on max_latencyJackie Liu
commit 424b650f35c77defbb3cbd6e5221d3697af42250 upstream. The compiler warns when the data are actually unused: kernel/trace/trace.c:1712:13: error: ‘trace_create_maxlat_file’ defined but not used [-Werror=unused-function] 1712 | static void trace_create_maxlat_file(struct trace_array *tr, | ^~~~~~~~~~~~~~~~~~~~~~~~ [Why] CONFIG_HWLAT_TRACER=n, CONFIG_TRACER_MAX_TRACE=n, CONFIG_OSNOISE_TRACER=y gcc report warns. [How] Now trace_create_maxlat_file will only take effect when CONFIG_HWLAT_TRACER=y or CONFIG_TRACER_MAX_TRACE=y. In fact, after adding osnoise trace, it also needs to take effect. Link: https://lore.kernel.org/all/c1d9e328-ad7c-920b-6c24-9e1598a6421c@infradead.org/ Link: https://lkml.kernel.org/r/20210922025122.3268022-1-liu.yun@linux.dev Fixes: bce29ac9ce0b ("trace: Add osnoise tracer") Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@kernel.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Jackie Liu <liuyun01@kylinos.cn> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-30blktrace: Fix uaf in blk_trace access after removing by sysfsZhihao Cheng
[ Upstream commit 5afedf670caf30a2b5a52da96eb7eac7dee6a9c9 ] There is an use-after-free problem triggered by following process: P1(sda) P2(sdb) echo 0 > /sys/block/sdb/trace/enable blk_trace_remove_queue synchronize_rcu blk_trace_free relay_close rcu_read_lock __blk_add_trace trace_note_tsk (Iterate running_trace_list) relay_close_buf relay_destroy_buf kfree(buf) trace_note(sdb's bt) relay_reserve buf->offset <- nullptr deference (use-after-free) !!! rcu_read_unlock [ 502.714379] BUG: kernel NULL pointer dereference, address: 0000000000000010 [ 502.715260] #PF: supervisor read access in kernel mode [ 502.715903] #PF: error_code(0x0000) - not-present page [ 502.716546] PGD 103984067 P4D 103984067 PUD 17592b067 PMD 0 [ 502.717252] Oops: 0000 [#1] SMP [ 502.720308] RIP: 0010:trace_note.isra.0+0x86/0x360 [ 502.732872] Call Trace: [ 502.733193] __blk_add_trace.cold+0x137/0x1a3 [ 502.733734] blk_add_trace_rq+0x7b/0xd0 [ 502.734207] blk_add_trace_rq_issue+0x54/0xa0 [ 502.734755] blk_mq_start_request+0xde/0x1b0 [ 502.735287] scsi_queue_rq+0x528/0x1140 ... [ 502.742704] sg_new_write.isra.0+0x16e/0x3e0 [ 502.747501] sg_ioctl+0x466/0x1100 Reproduce method: ioctl(/dev/sda, BLKTRACESETUP, blk_user_trace_setup[buf_size=127]) ioctl(/dev/sda, BLKTRACESTART) ioctl(/dev/sdb, BLKTRACESETUP, blk_user_trace_setup[buf_size=127]) ioctl(/dev/sdb, BLKTRACESTART) echo 0 > /sys/block/sdb/trace/enable & // Add delay(mdelay/msleep) before kernel enters blk_trace_free() ioctl$SG_IO(/dev/sda, SG_IO, ...) // Enters trace_note_tsk() after blk_trace_free() returned // Use mdelay in rcu region rather than msleep(which may schedule out) Remove blk_trace from running_list before calling blk_trace_free() by sysfs if blk_trace is at Blktrace_running state. Fixes: c71a896154119f ("blktrace: add ftrace plugin") Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com> Link: https://lore.kernel.org/r/20210923134921.109194-1-chengzhihao1@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-26tracing/boot: Fix to loop on only subkeysMasami Hiramatsu
[ Upstream commit cfd799837dbc48499abb05d1891b3d9992354d3a ] Since the commit e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key") allows to co-exist a value node and key nodes under a node, xbc_node_for_each_child() is not only returning key node but also a value node. In the boot-time tracing using xbc_node_for_each_child() to iterate the events, groups and instances, but those must be key nodes. Thus it must use xbc_node_for_each_subkey(). Link: https://lkml.kernel.org/r/163112988361.74896.2267026262061819145.stgit@devnote2 Fixes: e5efaeb8a8f5 ("bootconfig: Support mixing a value and subkeys under a key") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22tracing/boot: Fix a hist trigger dependency for boot time tracingMasami Hiramatsu
[ Upstream commit 6fe7c745f2acb73e4cc961d7f91125eef5a8861f ] Fixes a build error when CONFIG_HIST_TRIGGERS=n with boot-time tracing. Since the trigger_process_regex() is defined only when CONFIG_HIST_TRIGGERS=y, if it is disabled, the 'actions' event option also must be disabled. Link: https://lkml.kernel.org/r/162856123376.203126.582144262622247352.stgit@devnote2 Fixes: 81a59555ff15 ("tracing/boot: Add per-event settings") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22tracing/probes: Reject events which have the same name of existing oneMasami Hiramatsu
[ Upstream commit 8e242060c6a4947e8ae7d29794af6a581db08841 ] Since kprobe_events and uprobe_events only check whether the other same-type probe event has the same name or not, if the user gives the same name of the existing tracepoint event (or the other type of probe events), it silently fails to create the tracefs entry (but registered.) as below. /sys/kernel/tracing # ls events/task/task_rename enable filter format hist id trigger /sys/kernel/tracing # echo p:task/task_rename vfs_read >> kprobe_events [ 113.048508] Could not create tracefs 'task_rename' directory /sys/kernel/tracing # cat kprobe_events p:task/task_rename vfs_read To fix this issue, check whether the existing events have the same name or not in trace_probe_register_event_call(). If exists, it rejects to register the new event. Link: https://lkml.kernel.org/r/162936876189.187130.17558311387542061930.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-18tracing/osnoise: Fix missed cpus_read_unlock() in start_per_cpu_kthreads()Qiang.Zhang
commit 4b6b08f2e45edda4c067ac40833e3c1f84383c0b upstream. When start_kthread() return error, the cpus_read_unlock() need to be called. Link: https://lkml.kernel.org/r/20210831022919.27630-1-qiang.zhang@windriver.com Cc: <stable@vger.kernel.org> Fixes: c8895e271f79 ("trace/osnoise: Support hotplug operations") Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Qiang.Zhang <qiang.zhang@windriver.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-17Merge tag 'trace-v5.14-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Limit the shooting in the foot of tp_printk The "tp_printk" option redirects the trace event output to printk at boot up. This is useful when a machine crashes before boot where the trace events can not be retrieved by the in kernel ring buffer. But it can be "dangerous" because trace events can be located in high frequency locations such as interrupts and the scheduler, where a printk can slow it down that it live locks the machine (because by the time the printk finishes, the next event is triggered). Thus tp_printk must be used with care. It was discovered that the filter logic to trace events does not apply to the tp_printk events. This can cause a surprise and live lock when the user expects it to be filtered to limit the amount of events printed to the console when in fact it still prints everything" * tag 'trace-v5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Apply trace filters on all output channels
2021-08-16Merge tag 'trace-v5.14-rc5-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Fixes and clean ups to tracing: - Fix header alignment when PREEMPT_RT is enabled for osnoise tracer - Inject "stop" event to see where osnoise stopped the trace - Define DYNAMIC_FTRACE_WITH_ARGS as some code had an #ifdef for it - Fix erroneous message for bootconfig cmdline parameter - Fix crash caused by not found variable in histograms" * tag 'trace-v5.14-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing / histogram: Fix NULL pointer dereference on strcmp() on NULL event name init: Suppress wrong warning for bootconfig cmdline parameter tracing: define needed config DYNAMIC_FTRACE_WITH_ARGS trace/osnoise: Print a stop tracing message trace/timerlat: Add a header with PREEMPT_RT additional fields trace/osnoise: Add a header with PREEMPT_RT additional fields
2021-08-16tracing: Apply trace filters on all output channelsPingfan Liu
The event filters are not applied on all of the output, which results in the flood of printk when using tp_printk. Unfolding event_trigger_unlock_commit_regs() into trace_event_buffer_commit(), so the filters can be applied on every output. Link: https://lkml.kernel.org/r/20210814034538.8428-1-kernelfans@gmail.com Cc: stable@vger.kernel.org Fixes: 0daa2302968c1 ("tracing: Add tp_printk cmdline to have tracepoints go to printk()") Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-12tracing / histogram: Fix NULL pointer dereference on strcmp() on NULL event nameSteven Rostedt (VMware)
The following commands: # echo 'read_max u64 size;' > synthetic_events # echo 'hist:keys=common_pid:count=count:onmax($count).trace(read_max,count)' > events/syscalls/sys_enter_read/trigger Causes: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 4 PID: 1763 Comm: bash Not tainted 5.14.0-rc2-test+ #155 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:strcmp+0xc/0x20 Code: 75 f7 31 c0 0f b6 0c 06 88 0c 02 48 83 c0 01 84 c9 75 f1 4c 89 c0 c3 0f 1f 80 00 00 00 00 31 c0 eb 08 48 83 c0 01 84 d2 74 0f <0f> b6 14 07 3a 14 06 74 ef 19 c0 83 c8 01 c3 31 c0 c3 66 90 48 89 RSP: 0018:ffffb5fdc0963ca8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffffb3a4e040 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff9714c0d0b640 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00000022986b7cde R09: ffffffffb3a4dff8 R10: 0000000000000000 R11: 0000000000000000 R12: ffff9714c50603c8 R13: 0000000000000000 R14: ffff97143fdf9e48 R15: ffff9714c01a2210 FS: 00007f1fa6785740(0000) GS:ffff9714da400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000002d863004 CR4: 00000000001706e0 Call Trace: __find_event_file+0x4e/0x80 action_create+0x6b7/0xeb0 ? kstrdup+0x44/0x60 event_hist_trigger_func+0x1a07/0x2130 trigger_process_regex+0xbd/0x110 event_trigger_write+0x71/0xd0 vfs_write+0xe9/0x310 ksys_write+0x68/0xe0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1fa6879e87 The problem was the "trace(read_max,count)" where the "count" should be "$count" as "onmax()" only handles variables (although it really should be able to figure out that "count" is a field of sys_enter_read). But there's a path that does not find the variable and ends up passing a NULL for the event, which ends up getting passed to "strcmp()". Add a check for NULL to return and error on the command with: # cat error_log hist:syscalls:sys_enter_read: error: Couldn't create or find variable Command: hist:keys=common_pid:count=count:onmax($count).trace(read_max,count) ^ Link: https://lkml.kernel.org/r/20210808003011.4037f8d0@oasis.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: stable@vger.kernel.org Fixes: 50450603ec9cb tracing: Add 'onmax' hist trigger action support Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-12tracing: define needed config DYNAMIC_FTRACE_WITH_ARGSLukas Bulwahn
Commit 2860cd8a2353 ("livepatch: Use the default ftrace_ops instead of REGS when ARGS is available") intends to enable config LIVEPATCH when ftrace with ARGS is available. However, the chain of configs to enable LIVEPATCH is incomplete, as HAVE_DYNAMIC_FTRACE_WITH_ARGS is available, but the definition of DYNAMIC_FTRACE_WITH_ARGS, combining DYNAMIC_FTRACE and HAVE_DYNAMIC_FTRACE_WITH_ARGS, needed to enable LIVEPATCH, is missing in the commit. Fortunately, ./scripts/checkkconfigsymbols.py detects this and warns: DYNAMIC_FTRACE_WITH_ARGS Referencing files: kernel/livepatch/Kconfig So, define the config DYNAMIC_FTRACE_WITH_ARGS analogously to the already existing similar configs, DYNAMIC_FTRACE_WITH_REGS and DYNAMIC_FTRACE_WITH_DIRECT_CALLS, in ./kernel/trace/Kconfig to connect the chain of configs. Link: https://lore.kernel.org/kernel-janitors/CAKXUXMwT2zS9fgyQHKUUiqo8ynZBdx2UEUu1WnV_q0OCmknqhw@mail.gmail.com/ Link: https://lkml.kernel.org/r/20210806195027.16808-1-lukas.bulwahn@gmail.com Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Miroslav Benes <mbenes@suse.cz> Cc: stable@vger.kernel.org Fixes: 2860cd8a2353 ("livepatch: Use the default ftrace_ops instead of REGS when ARGS is available") Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-12trace/osnoise: Print a stop tracing messageDaniel Bristot de Oliveira
When using osnoise/timerlat with stop tracing, sometimes it is not clear in which CPU the stop condition was hit, mainly when using some extra events. Print a message informing in which CPU the trace stopped, like in the example below: <idle>-0 [006] d.h. 2932.676616: #1672599 context irq timer_latency 34689 ns <idle>-0 [006] dNh. 2932.676618: irq_noise: local_timer:236 start 2932.676615639 duration 2391 ns <idle>-0 [006] dNh. 2932.676620: irq_noise: virtio0-output.0:47 start 2932.676620180 duration 86 ns <idle>-0 [003] d.h. 2932.676621: #1673374 context irq timer_latency 1200 ns <idle>-0 [006] d... 2932.676623: thread_noise: swapper/6:0 start 2932.676615964 duration 4339 ns <idle>-0 [003] dNh. 2932.676623: irq_noise: local_timer:236 start 2932.676620597 duration 1881 ns <idle>-0 [006] d... 2932.676623: sched_switch: prev_comm=swapper/6 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=timerlat/6 next_pid=852 next_prio=4 timerlat/6-852 [006] .... 2932.676623: #1672599 context thread timer_latency 41931 ns <idle>-0 [003] d... 2932.676623: thread_noise: swapper/3:0 start 2932.676620854 duration 880 ns <idle>-0 [003] d... 2932.676624: sched_switch: prev_comm=swapper/3 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=timerlat/3 next_pid=849 next_prio=4 timerlat/6-852 [006] .... 2932.676624: timerlat_main: stop tracing hit on cpu 6 timerlat/3-849 [003] .... 2932.676624: #1673374 context thread timer_latency 4310 ns Link: https://lkml.kernel.org/r/b30a0d7542adba019185f44ee648e60e14923b11.1626598844.git.bristot@kernel.org Cc: Tom Zanussi <zanussi@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-12trace/timerlat: Add a header with PREEMPT_RT additional fieldsDaniel Bristot de Oliveira
Some extra flags are printed to the trace header when using the PREEMPT_RT config. The extra flags are: need-resched-lazy, preempt-lazy-depth, and migrate-disable. Without printing these fields, the timerlat specific fields are shifted by three positions, for example: # tracer: timerlat # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # || / # |||| ACTIVATION # TASK-PID CPU# |||| TIMESTAMP ID CONTEXT LATENCY # | | | |||| | | | | <idle>-0 [000] d..h... 3279.798871: #1 context irq timer_latency 830 ns <...>-807 [000] ....... 3279.798881: #1 context thread timer_latency 11301 ns Add a new header for timerlat with the missing fields, to be used when the PREEMPT_RT is enabled. Link: https://lkml.kernel.org/r/babb83529a3211bd0805be0b8c21608230202c55.1626598844.git.bristot@kernel.org Cc: Tom Zanussi <zanussi@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-12trace/osnoise: Add a header with PREEMPT_RT additional fieldsDaniel Bristot de Oliveira
Some extra flags are printed to the trace header when using the PREEMPT_RT config. The extra flags are: need-resched-lazy, preempt-lazy-depth, and migrate-disable. Without printing these fields, the osnoise specific fields are shifted by three positions, for example: # tracer: osnoise # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth MAX # || / SINGLE Interference counters: # |||| RUNTIME NOISE %% OF CPU NOISE +-----------------------------+ # TASK-PID CPU# |||| TIMESTAMP IN US IN US AVAILABLE IN US HW NMI IRQ SIRQ THREAD # | | | |||| | | | | | | | | | | <...>-741 [000] ....... 1105.690909: 1000000 234 99.97660 36 21 0 1001 22 3 <...>-742 [001] ....... 1105.691923: 1000000 281 99.97190 197 7 0 1012 35 14 <...>-743 [002] ....... 1105.691958: 1000000 1324 99.86760 118 11 0 1016 155 143 <...>-744 [003] ....... 1105.691998: 1000000 109 99.98910 21 4 0 1004 33 7 <...>-745 [004] ....... 1105.692015: 1000000 2023 99.79770 97 37 0 1023 52 18 Add a new header for osnoise with the missing fields, to be used when the PREEMPT_RT is enabled. Link: https://lkml.kernel.org/r/1f03289d2a51fde5a58c2e7def063dc630820ad1.1626598844.git.bristot@kernel.org Cc: Tom Zanussi <zanussi@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-10bpf: Add lockdown check for probe_write_user helperDaniel Borkmann
Back then, commit 96ae52279594 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers") added the bpf_probe_write_user() helper in order to allow to override user space memory. Its original goal was to have a facility to "debug, divert, and manipulate execution of semi-cooperative processes" under CAP_SYS_ADMIN. Write to kernel was explicitly disallowed since it would otherwise tamper with its integrity. One use case was shown in cf9b1199de27 ("samples/bpf: Add test/example of using bpf_probe_write_user bpf helper") where the program DNATs traffic at the time of connect(2) syscall, meaning, it rewrites the arguments to a syscall while they're still in userspace, and before the syscall has a chance to copy the argument into kernel space. These days we have better mechanisms in BPF for achieving the same (e.g. for load-balancers), but without having to write to userspace memory. Of course the bpf_probe_write_user() helper can also be used to abuse many other things for both good or bad purpose. Outside of BPF, there is a similar mechanism for ptrace(2) such as PTRACE_PEEK{TEXT,DATA} and PTRACE_POKE{TEXT,DATA}, but would likely require some more effort. Commit 96ae52279594 explicitly dedicated the helper for experimentation purpose only. Thus, move the helper's availability behind a newly added LOCKDOWN_BPF_WRITE_USER lockdown knob so that the helper is disabled under the "integrity" mode. More fine-grained control can be implemented also from LSM side with this change. Fixes: 96ae52279594 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org>
2021-08-09bpf: Add _kernel suffix to internal lockdown_bpf_readDaniel Borkmann
Rename LOCKDOWN_BPF_READ into LOCKDOWN_BPF_READ_KERNEL so we have naming more consistent with a LOCKDOWN_BPF_WRITE_USER option that we are adding. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org>
2021-08-05tracing: Quiet smp_processor_id() use in preemptable warning in hwlatSteven Rostedt (VMware)
The hardware latency detector (hwlat) has a mode that it runs one thread across CPUs. The logic to move from the currently running CPU to the next one in the list does a smp_processor_id() to find where it currently is. Unfortunately, it's done with preemption enabled, and this triggers a warning for using smp_processor_id() in a preempt enabled section. As it is only using smp_processor_id() to get information on where it currently is in order to simply move it to the next CPU, it doesn't really care if it got moved in the mean time. It will simply balance out later if such a case arises. Switch smp_processor_id() to raw_smp_processor_id() to quiet that warning. Link: https://lkml.kernel.org/r/20210804141848.79edadc0@oasis.local.home Acked-by: Daniel Bristot de Oliveira <bristot@redhat.com> Fixes: 8fa826b7344d ("trace/hwlat: Implement the mode config option") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-04tracing: Reject string operand in the histogram expressionMasami Hiramatsu
Since the string type can not be the target of the addition / subtraction operation, it must be rejected. Without this fix, the string type silently converted to digits. Link: https://lkml.kernel.org/r/162742654278.290973.1523000673366456634.stgit@devnote2 Cc: stable@vger.kernel.org Fixes: 100719dcef447 ("tracing: Add simple expression support to hist triggers") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-08-04tracing / histogram: Give calculation hist_fields a sizeSteven Rostedt (VMware)
When working on my user space applications, I found a bug in the synthetic event code where the automated synthetic event field was not matching the event field calculation it was attached to. Looking deeper into it, it was because the calculation hist_field was not given a size. The synthetic event fields are matched to their hist_fields either by having the field have an identical string type, or if that does not match, then the size and signed values are used to match the fields. The problem arose when I tried to match a calculation where the fields were "unsigned int". My tool created a synthetic event of type "u32". But it failed to match. The string was: diff=field1-field2:onmatch(event).trace(synth,$diff) Adding debugging into the kernel, I found that the size of "diff" was 0. And since it was given "unsigned int" as a type, the histogram fallback code used size and signed. The signed matched, but the size of u32 (4) did not match zero, and the event failed to be created. This can be worse if the field you want to match is not one of the acceptable fields for a synthetic event. As event fields can have any type that is supported in Linux, this can cause an issue. For example, if a type is an enum. Then there's no way to use that with any calculations. Have the calculation field simply take on the size of what it is calculating. Link: https://lkml.kernel.org/r/20210730171951.59c7743f@oasis.local.home Cc: Tom Zanussi <zanussi@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Fixes: 100719dcef447 ("tracing: Add simple expression support to hist triggers") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-30tracing: Fix NULL pointer dereference in start_creatingKamal Agrawal
The event_trace_add_tracer() can fail. In this case, it leads to a crash in start_creating with below call stack. Handle the error scenario properly in trace_array_create_dir. Call trace: down_write+0x7c/0x204 start_creating.25017+0x6c/0x194 tracefs_create_file+0xc4/0x2b4 init_tracer_tracefs+0x5c/0x940 trace_array_create_dir+0x58/0xb4 trace_array_create+0x1bc/0x2b8 trace_array_get_by_name+0xdc/0x18c Link: https://lkml.kernel.org/r/1627651386-21315-1-git-send-email-kamaagra@codeaurora.org Cc: stable@vger.kernel.org Fixes: 4114fbfd02f1 ("tracing: Enable creating new instance early boot") Signed-off-by: Kamal Agrawal <kamaagra@codeaurora.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-23ftrace: Remove redundant initialization of variable retColin Ian King
The variable ret is being initialized with a value that is never read, it is being updated later on. The assignment is redundant and can be removed. Link: https://lkml.kernel.org/r/20210721120915.122278-1-colin.king@canonical.com Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-23ftrace: Avoid synchronize_rcu_tasks_rude() call when not necessaryNicolas Saenz Julienne
synchronize_rcu_tasks_rude() triggers IPIs and forces rescheduling on all CPUs. It is a costly operation and, when targeting nohz_full CPUs, very disrupting (hence the name). So avoid calling it when 'old_hash' doesn't need to be freed. Link: https://lkml.kernel.org/r/20210721114726.1545103-1-nsaenzju@redhat.com Signed-off-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-23tracing: Clean up alloc_synth_event()Steven Rostedt (VMware)
alloc_synth_event() currently has the following code to initialize the event fields and dynamic_fields: for (i = 0, j = 0; i < n_fields; i++) { event->fields[i] = fields[i]; if (fields[i]->is_dynamic) { event->dynamic_fields[j] = fields[i]; event->dynamic_fields[j]->field_pos = i; event->dynamic_fields[j++] = fields[i]; event->n_dynamic_fields++; } } 1) It would make more sense to have all fields keep track of their field_pos. 2) event->dynmaic_fields[j] is assigned twice for no reason. 3) We can move updating event->n_dynamic_fields outside the loop, and just assign it to j. This combination makes the code much cleaner. Link: https://lkml.kernel.org/r/20210721195341.29bb0f77@oasis.local.home Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-23tracing/histogram: Rename "cpu" to "common_cpu"Steven Rostedt (VMware)
Currently the histogram logic allows the user to write "cpu" in as an event field, and it will record the CPU that the event happened on. The problem with this is that there's a lot of events that have "cpu" as a real field, and using "cpu" as the CPU it ran on, makes it impossible to run histograms on the "cpu" field of events. For example, if I want to have a histogram on the count of the workqueue_queue_work event on its cpu field, running: ># echo 'hist:keys=cpu' > events/workqueue/workqueue_queue_work/trigger Gives a misleading and wrong result. Change the command to "common_cpu" as no event should have "common_*" fields as that's a reserved name for fields used by all events. And this makes sense here as common_cpu would be a field used by all events. Now we can even do: ># echo 'hist:keys=common_cpu,cpu if cpu < 100' > events/workqueue/workqueue_queue_work/trigger ># cat events/workqueue/workqueue_queue_work/hist # event histogram # # trigger info: hist:keys=common_cpu,cpu:vals=hitcount:sort=hitcount:size=2048 if cpu < 100 [active] # { common_cpu: 0, cpu: 2 } hitcount: 1 { common_cpu: 0, cpu: 4 } hitcount: 1 { common_cpu: 7, cpu: 7 } hitcount: 1 { common_cpu: 0, cpu: 7 } hitcount: 1 { common_cpu: 0, cpu: 1 } hitcount: 1 { common_cpu: 0, cpu: 6 } hitcount: 2 { common_cpu: 0, cpu: 5 } hitcount: 2 { common_cpu: 1, cpu: 1 } hitcount: 4 { common_cpu: 6, cpu: 6 } hitcount: 4 { common_cpu: 5, cpu: 5 } hitcount: 14 { common_cpu: 4, cpu: 4 } hitcount: 26 { common_cpu: 0, cpu: 0 } hitcount: 39 { common_cpu: 2, cpu: 2 } hitcount: 184 Now for backward compatibility, I added a trick. If "cpu" is used, and the field is not found, it will fall back to "common_cpu" and work as it did before. This way, it will still work for old programs that use "cpu" to get the actual CPU, but if the event has a "cpu" as a field, it will get that event's "cpu" field, which is probably what it wants anyway. I updated the tracefs/README to include documentation about both the common_timestamp and the common_cpu. This way, if that text is present in the README, then an application can know that common_cpu is supported over just plain "cpu". Link: https://lkml.kernel.org/r/20210721110053.26b4f641@oasis.local.home Cc: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Fixes: 8b7622bf94a44 ("tracing: Add cpu field for hist triggers") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-23tracing: Synthetic event field_pos is an index not a booleanSteven Rostedt (VMware)
Performing the following: ># echo 'wakeup_lat s32 pid; u64 delta; char wake_comm[]' > synthetic_events ># echo 'hist:keys=pid:__arg__1=common_timestamp.usecs' > events/sched/sched_waking/trigger ># echo 'hist:keys=next_pid:pid=next_pid,delta=common_timestamp.usecs-$__arg__1:onmatch(sched.sched_waking).trace(wakeup_lat,$pid,$delta,prev_comm)'\ > events/sched/sched_switch/trigger ># echo 1 > events/synthetic/enable Crashed the kernel: BUG: kernel NULL pointer dereference, address: 000000000000001b #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.13.0-rc5-test+ #104 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:strlen+0x0/0x20 Code: f6 82 80 2b 0b bc 20 74 11 0f b6 50 01 48 83 c0 01 f6 82 80 2b 0b bc 20 75 ef c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 9 f8 c3 31 RSP: 0018:ffffaa75000d79d0 EFLAGS: 00010046 RAX: 0000000000000002 RBX: ffff9cdb55575270 RCX: 0000000000000000 RDX: ffff9cdb58c7a320 RSI: ffffaa75000d7b40 RDI: 000000000000001b RBP: ffffaa75000d7b40 R08: ffff9cdb40a4f010 R09: ffffaa75000d7ab8 R10: ffff9cdb4398c700 R11: 0000000000000008 R12: ffff9cdb58c7a320 R13: ffff9cdb55575270 R14: ffff9cdb58c7a000 R15: 0000000000000018 FS: 0000000000000000(0000) GS:ffff9cdb5aa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000001b CR3: 00000000c0612006 CR4: 00000000001706e0 Call Trace: trace_event_raw_event_synth+0x90/0x1d0 action_trace+0x5b/0x70 event_hist_trigger+0x4bd/0x4e0 ? cpumask_next_and+0x20/0x30 ? update_sd_lb_stats.constprop.0+0xf6/0x840 ? __lock_acquire.constprop.0+0x125/0x550 ? find_held_lock+0x32/0x90 ? sched_clock_cpu+0xe/0xd0 ? lock_release+0x155/0x440 ? update_load_avg+0x8c/0x6f0 ? enqueue_entity+0x18a/0x920 ? __rb_reserve_next+0xe5/0x460 ? ring_buffer_lock_reserve+0x12a/0x3f0 event_triggers_call+0x52/0xe0 trace_event_buffer_commit+0x1ae/0x240 trace_event_raw_event_sched_switch+0x114/0x170 __traceiter_sched_switch+0x39/0x50 __schedule+0x431/0xb00 schedule_idle+0x28/0x40 do_idle+0x198/0x2e0 cpu_startup_entry+0x19/0x20 secondary_startup_64_no_verify+0xc2/0xcb The reason is that the dynamic events array keeps track of the field position of the fields array, via the field_pos variable in the synth_field structure. Unfortunately, that field is a boolean for some reason, which means any field_pos greater than 1 will be a bug (in this case it was 2). Link: https://lkml.kernel.org/r/20210721191008.638bce34@oasis.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Fixes: bd82631d7ccdc ("tracing: Add support for dynamic strings to synthetic events") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-22tracing: Fix bug in rb_per_cpu_empty() that might cause deadloop.Haoran Luo
The "rb_per_cpu_empty()" misinterpret the condition (as not-empty) when "head_page" and "commit_page" of "struct ring_buffer_per_cpu" points to the same buffer page, whose "buffer_data_page" is empty and "read" field is non-zero. An error scenario could be constructed as followed (kernel perspective): 1. All pages in the buffer has been accessed by reader(s) so that all of them will have non-zero "read" field. 2. Read and clear all buffer pages so that "rb_num_of_entries()" will return 0 rendering there's no more data to read. It is also required that the "read_page", "commit_page" and "tail_page" points to the same page, while "head_page" is the next page of them. 3. Invoke "ring_buffer_lock_reserve()" with large enough "length" so that it shot pass the end of current tail buffer page. Now the "head_page", "commit_page" and "tail_page" points to the same page. 4. Discard current event with "ring_buffer_discard_commit()", so that "head_page", "commit_page" and "tail_page" points to a page whose buffer data page is now empty. When the error scenario has been constructed, "tracing_read_pipe" will be trapped inside a deadloop: "trace_empty()" returns 0 since "rb_per_cpu_empty()" returns 0 when it hits the CPU containing such constructed ring buffer. Then "trace_find_next_entry_inc()" always return NULL since "rb_num_of_entries()" reports there's no more entry to read. Finally "trace_seq_to_user()" returns "-EBUSY" spanking "tracing_read_pipe" back to the start of the "waitagain" loop. I've also written a proof-of-concept script to construct the scenario and trigger the bug automatically, you can use it to trace and validate my reasoning above: https://github.com/aegistudio/RingBufferDetonator.git Tests has been carried out on linux kernel 5.14-rc2 (2734d6c1b1a089fb593ef6a23d4b70903526fe0c), my fixed version of kernel (for testing whether my update fixes the bug) and some older kernels (for range of affected kernels). Test result is also attached to the proof-of-concept repository. Link: https://lore.kernel.org/linux-trace-devel/YPaNxsIlb2yjSi5Y@aegistudio/ Link: https://lore.kernel.org/linux-trace-devel/YPgrN85WL9VyrZ55@aegistudio Cc: stable@vger.kernel.org Fixes: bf41a158cacba ("ring-buffer: make reentrant") Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Haoran Luo <www@aegistudio.net> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-17Merge tag 'trace-v5.14-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Fix the histogram logic from possibly crashing the kernel Working on the histogram code, I found that if you dereference a char pointer in a trace event that happens to point to user space, it can crash the kernel, as it does no checks of that pointer. I have code coming that will do this better, so just remove this ability to treat character pointers in trace events as stings in the histogram" * tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Do not reference char * as a string in histograms
2021-07-15tracing: Do not reference char * as a string in histogramsSteven Rostedt (VMware)
The histogram logic was allowing events with char * pointers to be used as normal strings. But it was easy to crash the kernel with: # echo 'hist:keys=filename' > events/syscalls/sys_enter_openat/trigger And open some files, and boom! BUG: unable to handle page fault for address: 00007f2ced0c3280 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 1173fa067 P4D 1173fa067 PUD 1171b6067 PMD 1171dd067 PTE 0 Oops: 0000 [#1] PREEMPT SMP CPU: 6 PID: 1810 Comm: cat Not tainted 5.13.0-rc5-test+ #61 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:strlen+0x0/0x20 Code: f6 82 80 2a 0b a9 20 74 11 0f b6 50 01 48 83 c0 01 f6 82 80 2a 0b a9 20 75 ef c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <80> 3f 00 74 10 48 89 f8 48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 RSP: 0018:ffffbdbf81567b50 EFLAGS: 00010246 RAX: 0000000000000003 RBX: ffff93815cdb3800 RCX: ffff9382401a22d0 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 00007f2ced0c3280 RBP: 0000000000000100 R08: ffff9382409ff074 R09: ffffbdbf81567c98 R10: ffff9382409ff074 R11: 0000000000000000 R12: ffff9382409ff074 R13: 0000000000000001 R14: ffff93815a744f00 R15: 00007f2ced0c3280 FS: 00007f2ced0f8580(0000) GS:ffff93825a800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2ced0c3280 CR3: 0000000107069005 CR4: 00000000001706e0 Call Trace: event_hist_trigger+0x463/0x5f0 ? find_held_lock+0x32/0x90 ? sched_clock_cpu+0xe/0xd0 ? lock_release+0x155/0x440 ? kernel_init_free_pages+0x6d/0x90 ? preempt_count_sub+0x9b/0xd0 ? kernel_init_free_pages+0x6d/0x90 ? get_page_from_freelist+0x12c4/0x1680 ? __rb_reserve_next+0xe5/0x460 ? ring_buffer_lock_reserve+0x12a/0x3f0 event_triggers_call+0x52/0xe0 ftrace_syscall_enter+0x264/0x2c0 syscall_trace_enter.constprop.0+0x1ee/0x210 do_syscall_64+0x1c/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Where it triggered a fault on strlen(key) where key was the filename. The reason is that filename is a char * to user space, and the histogram code just blindly dereferenced it, with obvious bad results. I originally tried to use strncpy_from_user/kernel_nofault() but found that there's other places that its dereferenced and not worth the effort. Just do not allow "char *" to act like strings. Link: https://lkml.kernel.org/r/20210715000206.025df9d2@rorschach.local.home Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com> Cc: stable@vger.kernel.org Acked-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Tom Zanussi <zanussi@kernel.org> Fixes: 79e577cbce4c4 ("tracing: Support string type key properly") Fixes: 5967bd5c4239 ("tracing: Let filter_assign_type() detect FILTER_PTR_STRING") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-09Merge tag 'trace-v5.14-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix and cleanup from Steven Rostedt: "Tracing fix for histograms and a clean up in ftrace: - Fixed a bug that broke the .sym-offset modifier and added a test to make sure nothing breaks it again. - Replace a list_del/list_add() with a list_move()" * tag 'trace-v5.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Use list_move instead of list_del/list_add tracing/selftests: Add tests to test histogram sym and sym-offset modifiers tracing/histograms: Fix parsing of "sym-offset" modifier
2021-07-08ftrace: Use list_move instead of list_del/list_addBaokun Li
Using list_move() instead of list_del() + list_add(). Link: https://lkml.kernel.org/r/20210608031108.2820996-1-libaokun1@huawei.com Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Baokun Li <libaokun1@huawei.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-07tracing/histograms: Fix parsing of "sym-offset" modifierSteven Rostedt (VMware)
With the addition of simple mathematical operations (plus and minus), the parsing of the "sym-offset" modifier broke, as it took the '-' part of the "sym-offset" as a minus, and tried to break it up into a mathematical operation of "field.sym - offset", in which case it failed to parse (unless the event had a field called "offset"). Both .sym and .sym-offset modifiers should not be entered into mathematical calculations anyway. If ".sym-offset" is found in the modifier, then simply make it not an operation that can be calculated on. Link: https://lkml.kernel.org/r/20210707110821.188ae255@oasis.local.home Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: stable@vger.kernel.org Fixes: 100719dcef447 ("tracing: Add simple expression support to hist triggers") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-03Merge tag 'trace-v5.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Added option for per CPU threads to the hwlat tracer - Have hwlat tracer handle hotplug CPUs - New tracer: osnoise, that detects latency caused by interrupts, softirqs and scheduling of other tasks. - Added timerlat tracer that creates a thread and measures in detail what sources of latency it has for wake ups. - Removed the "success" field of the sched_wakeup trace event. This has been hardcoded as "1" since 2015, no tooling should be looking at it now. If one exists, we can revert this commit, fix that tool and try to remove it again in the future. - tgid mapping fixed to handle more than PID_MAX_DEFAULT pids/tgids. - New boot command line option "tp_printk_stop", as tp_printk causes trace events to write to console. When user space starts, this can easily live lock the system. Having a boot option to stop just after boot up is useful to prevent that from happening. - Have ftrace_dump_on_oops boot command line option take numbers that match the numbers shown in /proc/sys/kernel/ftrace_dump_on_oops. - Bootconfig clean ups, fixes and enhancements. - New ktest script that tests bootconfig options. - Add tracepoint_probe_register_may_exist() to register a tracepoint without triggering a WARN*() if it already exists. BPF has a path from user space that can do this. All other paths are considered a bug. - Small clean ups and fixes * tag 'trace-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (49 commits) tracing: Resize tgid_map to pid_max, not PID_MAX_DEFAULT tracing: Simplify & fix saved_tgids logic treewide: Add missing semicolons to __assign_str uses tracing: Change variable type as bool for clean-up trace/timerlat: Fix indentation on timerlat_main() trace/osnoise: Make 'noise' variable s64 in run_osnoise() tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing tracing: Fix spelling in osnoise tracer "interferences" -> "interference" Documentation: Fix a typo on trace/osnoise-tracer trace/osnoise: Fix return value on osnoise_init_hotplug_support trace/osnoise: Make interval u64 on osnoise_main trace/osnoise: Fix 'no previous prototype' warnings tracing: Have osnoise_main() add a quiescent state for task rcu seq_buf: Make trace_seq_putmem_hex() support data longer than 8 seq_buf: Fix overflow in seq_buf_putmem_hex() trace/osnoise: Support hotplug operations trace/hwlat: Support hotplug operations trace/hwlat: Protect kdata->kthread with get/put_online_cpus trace: Add timerlat tracer trace: Add osnoise tracer ...
2021-07-02Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: "190 patches. Subsystems affected by this patch series: mm (hugetlb, userfaultfd, vmscan, kconfig, proc, z3fold, zbud, ras, mempolicy, memblock, migration, thp, nommu, kconfig, madvise, memory-hotplug, zswap, zsmalloc, zram, cleanups, kfence, and hmm), procfs, sysctl, misc, core-kernel, lib, lz4, checkpatch, init, kprobes, nilfs2, hfs, signals, exec, kcov, selftests, compress/decompress, and ipc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits) ipc/util.c: use binary search for max_idx ipc/sem.c: use READ_ONCE()/WRITE_ONCE() for use_global_lock ipc: use kmalloc for msg_queue and shmid_kernel ipc sem: use kvmalloc for sem_undo allocation lib/decompressors: remove set but not used variabled 'level' selftests/vm/pkeys: exercise x86 XSAVE init state selftests/vm/pkeys: refill shadow register after implicit kernel write selftests/vm/pkeys: handle negative sys_pkey_alloc() return code selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random kcov: add __no_sanitize_coverage to fix noinstr for all architectures exec: remove checks in __register_bimfmt() x86: signal: don't do sas_ss_reset() until we are certain that sigframe won't be abandoned hfsplus: report create_date to kstat.btime hfsplus: remove unnecessary oom message nilfs2: remove redundant continue statement in a while-loop kprobes: remove duplicated strong free_insn_page in x86 and s390 init: print out unknown kernel parameters checkpatch: do not complain about positive return values starting with EPOLL checkpatch: improve the indented label test checkpatch: scripts/spdxcheck.py now requires python3 ...
2021-07-01tracing: Resize tgid_map to pid_max, not PID_MAX_DEFAULTPaul Burton
Currently tgid_map is sized at PID_MAX_DEFAULT entries, which means that on systems where pid_max is configured higher than PID_MAX_DEFAULT the ftrace record-tgid option doesn't work so well. Any tasks with PIDs higher than PID_MAX_DEFAULT are simply not recorded in tgid_map, and don't show up in the saved_tgids file. In particular since systemd v243 & above configure pid_max to its highest possible 1<<22 value by default on 64 bit systems this renders the record-tgids option of little use. Increase the size of tgid_map to the configured pid_max instead, allowing it to cover the full range of PIDs up to the maximum value of PID_MAX_LIMIT if the system is configured that way. On 64 bit systems with pid_max == PID_MAX_LIMIT this will increase the size of tgid_map from 256KiB to 16MiB. Whilst this 64x increase in memory overhead sounds significant 64 bit systems are presumably best placed to accommodate it, and since tgid_map is only allocated when the record-tgid option is actually used presumably the user would rather it spends sufficient memory to actually record the tgids they expect. The size of tgid_map could also increase for CONFIG_BASE_SMALL=y configurations, but these seem unlikely to be systems upon which people are both configuring a large pid_max and running ftrace with record-tgid anyway. Of note is that we only allocate tgid_map once, the first time that the record-tgid option is enabled. Therefore its size is only set once, to the value of pid_max at the time the record-tgid option is first enabled. If a user increases pid_max after that point, the saved_tgids file will not contain entries for any tasks with pids beyond the earlier value of pid_max. Link: https://lkml.kernel.org/r/20210701172407.889626-2-paulburton@google.com Fixes: d914ba37d714 ("tracing: Add support for recording tgid of tasks") Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Fernandes <joelaf@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Paul Burton <paulburton@google.com> [ Fixed comment coding style ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-07-01kernel.h: split out panic and oops helpersAndy Shevchenko
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out panic and oops helpers. There are several purposes of doing this: - dropping dependency in bug.h - dropping a loop by moving out panic_notifier.h - unload kernel.h from something which has its own domain At the same time convert users tree-wide to use new headers, although for the time being include new header back to kernel.h to avoid twisted indirected includes for existing users. [akpm@linux-foundation.org: thread_info.h needs limits.h] [andriy.shevchenko@linux.intel.com: ia64 fix] Link: https://lkml.kernel.org/r/20210520130557.55277-1-andriy.shevchenko@linux.intel.com Link: https://lkml.kernel.org/r/20210511074137.33666-1-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Co-developed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Corey Minyard <cminyard@mvista.com> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Wei Liu <wei.liu@kernel.org> Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Sebastian Reichel <sre@kernel.org> Acked-by: Luis Chamberlain <mcgrof@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Acked-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30tracing: Simplify & fix saved_tgids logicPaul Burton
The tgid_map array records a mapping from pid to tgid, where the index of an entry within the array is the pid & the value stored at that index is the tgid. The saved_tgids_next() function iterates over pointers into the tgid_map array & dereferences the pointers which results in the tgid, but then it passes that dereferenced value to trace_find_tgid() which treats it as a pid & does a further lookup within the tgid_map array. It seems likely that the intent here was to skip over entries in tgid_map for which the recorded tgid is zero, but instead we end up skipping over entries for which the thread group leader hasn't yet had its own tgid recorded in tgid_map. A minimal fix would be to remove the call to trace_find_tgid, turning: if (trace_find_tgid(*ptr)) into: if (*ptr) ..but it seems like this logic can be much simpler if we simply let seq_read() iterate over the whole tgid_map array & filter out empty entries by returning SEQ_SKIP from saved_tgids_show(). Here we take that approach, removing the incorrect logic here entirely. Link: https://lkml.kernel.org/r/20210630003406.4013668-1-paulburton@google.com Fixes: d914ba37d714 ("tracing: Add support for recording tgid of tasks") Cc: Ingo Molnar <mingo@redhat.com> Cc: Joel Fernandes <joelaf@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Paul Burton <paulburton@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-30tracing: Change variable type as bool for clean-upAustin Kim
The wakeup_rt wakeup_dl, tracing_dl is only set to 0, 1. So changing type of wakeup_rt wakeup_dl, tracing_dl as bool makes relevant routine be more readable. Link: https://lkml.kernel.org/r/20210629140548.GA1627@raspberrypi Signed-off-by: Austin Kim <austin.kim@lge.com> [ Removed unneeded initialization of static bool tracing_dl ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-29trace/timerlat: Fix indentation on timerlat_main()Daniel Bristot de Oliveira
Dan Carpenter reported that: The patch a955d7eac177: "trace: Add timerlat tracer" from Jun 22, 2021, leads to the following static checker warning: kernel/trace/trace_osnoise.c:1400 timerlat_main() warn: inconsistent indenting here: 1389 while (!kthread_should_stop()) { 1390 now = ktime_to_ns(hrtimer_cb_get_time(&tlat->timer)); 1391 diff = now - tlat->abs_period; 1392 1393 s.seqnum = tlat->count; 1394 s.timer_latency = diff; 1395 s.context = THREAD_CONTEXT; 1396 1397 trace_timerlat_sample(&s); 1398 1399 #ifdef CONFIG_STACKTRACE 1400 if (osnoise_data.print_stack) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This should be indented another tab? 1401 if (osnoise_data.print_stack <= time_to_us(diff)) 1402 timerlat_dump_stack(); 1403 #endif /* CONFIG_STACKTRACE */ 1404 1405 tlat->tracing_thread = false; 1406 if (osnoise_data.stop_tracing_total) 1407 if (time_to_us(diff) >= osnoise_data.stop_tracing_total) 1408 osnoise_stop_tracing(); 1409 1410 wait_next_period(tlat); 1411 } And the static checker is right. Fix the indentation. Link: https://lkml.kernel.org/r/3d5d8c9258fbdcfa9d3c7362941b3d13a2a28d9d.1624986368.git.bristot@redhat.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: linux-kernel@vger.kernel.org Fixes: a955d7eac177 ("trace: Add timerlat tracer") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-29trace/osnoise: Make 'noise' variable s64 in run_osnoise()Daniel Bristot de Oliveira
Dab Carpenter reported that: The patch bce29ac9ce0b: "trace: Add osnoise tracer" from Jun 22, 2021, leads to the following static checker warning: kernel/trace/trace_osnoise.c:1103 run_osnoise() warn: unsigned 'noise' is never less than zero. In this part of the code: 1100 /* 1101 * This shouldn't happen. 1102 */ 1103 if (noise < 0) { ^^^^^^^^^ 1104 osnoise_taint("negative noise!"); 1105 goto out; 1106 } 1107 And the static checker is right because 'noise' is u64. Make noise s64 and keep the check. It is important to check if the time read is behaving correctly - so we can trust the results. I also re-arranged some variable declarations. Link: https://lkml.kernel.org/r/acd7cd6e7d56b798a298c3bc8139a390b3c4ab52.1624986368.git.bristot@redhat.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Daniel Bristot de Oliveira <bristot@redhat.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: linux-kernel@vger.kernel.org Fixes: bce29ac9ce0b ("trace: Add osnoise tracer") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-29tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracingSteven Rostedt (VMware)
All internal use cases for tracepoint_probe_register() is set to not ever be called with the same function and data. If it is, it is considered a bug, as that means the accounting of handling tracepoints is corrupted. If the function and data for a tracepoint is already registered when tracepoint_probe_register() is called, it will call WARN_ON_ONCE() and return with EEXISTS. The BPF system call can end up calling tracepoint_probe_register() with the same data, which now means that this can trigger the warning because of a user space process. As WARN_ON_ONCE() should not be called because user space called a system call with bad data, there needs to be a way to register a tracepoint without triggering a warning. Enter tracepoint_probe_register_may_exist(), which can be called, but will not cause a WARN_ON() if the probe already exists. It will still error out with EEXIST, which will then be sent to the user space that performed the BPF system call. This keeps the previous testing for issues with other users of the tracepoint code, while letting BPF call it with duplicated data and not warn about it. Link: https://lore.kernel.org/lkml/20210626135845.4080-1-penguin-kernel@I-love.SAKURA.ne.jp/ Link: https://syzkaller.appspot.com/bug?id=41f4318cf01762389f4d1c1c459da4f542fe5153 Cc: stable@vger.kernel.org Fixes: c4f6699dfcb85 ("bpf: introduce BPF_RAW_TRACEPOINT") Reported-by: syzbot <syzbot+721aa903751db87aa244@syzkaller.appspotmail.com> Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Tested-by: syzbot+721aa903751db87aa244@syzkaller.appspotmail.com Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-28once: implement DO_ONCE_LITE for non-fast-path "do once" functionalityTanner Love
Certain uses of "do once" functionality reside outside of fast path, and so do not require jump label patching via static keys, making existing DO_ONCE undesirable in such cases. Replace uses of __section(".data.once") with DO_ONCE_LITE(_IF)? This patch changes the return values of xfs_printk_once, printk_once, and printk_deferred_once. Before, they returned whether the print was performed, but now, they always return true. This is okay because the return values of the following macros are entirely ignored throughout the kernel: - xfs_printk_once - xfs_warn_once - xfs_notice_once - xfs_info_once - printk_once - pr_emerg_once - pr_alert_once - pr_crit_once - pr_err_once - pr_warn_once - pr_notice_once - pr_info_once - pr_devel_once - pr_debug_once - printk_deferred_once - orc_warn Changes v3: - Expand commit message to explain why changing return values of xfs_printk_once, printk_once, printk_deferred_once is benign v2: - Fix i386 build warnings Signed-off-by: Tanner Love <tannerlove@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Mahesh Bandewar <maheshb@google.com> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2021-06-28 The following pull-request contains BPF updates for your *net-next* tree. We've added 37 non-merge commits during the last 12 day(s) which contain a total of 56 files changed, 394 insertions(+), 380 deletions(-). The main changes are: 1) XDP driver RCU cleanups, from Toke Høiland-Jørgensen and Paul E. McKenney. 2) Fix bpf_skb_change_proto() IPv4/v6 GSO handling, from Maciej Żenczykowski. 3) Fix false positive kmemleak report for BPF ringbuf alloc, from Rustam Kovhaev. 4) Fix x86 JIT's extable offset calculation for PROBE_LDX NULL, from Ravi Bangoria. 5) Enable libbpf fallback probing with tracing under RHEL7, from Jonathan Edwards. 6) Clean up x86 JIT to remove unused cnt tracking from EMIT macro, from Jiri Olsa. 7) Netlink cleanups for libbpf to please Coverity, from Kumar Kartikeya Dwivedi. 8) Allow to retrieve ancestor cgroup id in tracing programs, from Namhyung Kim. 9) Fix lirc BPF program query to use user-provided prog_cnt, from Sean Young. 10) Add initial libbpf doc including generated kdoc for its API, from Grant Seltzer. 11) Make xdp_rxq_info_unreg_mem_model() more robust, from Jakub Kicinski. 12) Fix up bpfilter startup log-level to info level, from Gary Lin. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28trace/osnoise: Fix return value on osnoise_init_hotplug_supportDaniel Bristot de Oliveira
kernel test robot reported: >> kernel/trace/trace_osnoise.c:1584:2: error: void function 'osnoise_init_hotplug_support' should not return a value [-Wreturn-type] return 0; When !CONFIG_HOTPLUG_CPU. Fix it problem by removing the return value. Link: https://lkml.kernel.org/r/c7fc67f1a117cc88bab2e508c898634872795341.1624872608.git.bristot@redhat.com Fixes: c8895e271f79 ("trace/osnoise: Support hotplug operations") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-28trace/osnoise: Make interval u64 on osnoise_mainDaniel Bristot de Oliveira
kernel test robot reported: >> kernel/trace/trace_osnoise.c:966:3: warning: comparison of distinct pointer types ('typeof ((interval)) *' (aka 'long long *') and 'uint64_t *' (aka 'unsigned long long *')) [-Wcompare-distinct-pointer-types] do_div(interval, USEC_PER_MSEC); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/asm-generic/div64.h:228:28: note: expanded from macro 'do_div' (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \ ~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~ As interval cannot be negative because sample_period >= sample_runtime, making interval u64 on osnoise_main() is enough to fix this problem. Link: https://lkml.kernel.org/r/4ae1e7780563598563de079a3ef6d4d10b5f5546.1624872608.git.bristot@redhat.com Fixes: bce29ac9ce0b ("trace: Add osnoise tracer") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-06-28trace/osnoise: Fix 'no previous prototype' warningsDaniel Bristot de Oliveira
kernel test robot reported some osnoise functions with "no previous prototype." Fix these warnings by making local functions static, and by adding: void osnoise_trace_irq_entry(int id); void osnoise_trace_irq_exit(int id, const char *desc); to include/linux/trace.h. Link: https://lkml.kernel.org/r/e40d3cb4be8bde921f4b40fa6a095cf85ab807bd.1624872608.git.bristot@redhat.com Fixes: bce29ac9ce0b ("trace: Add osnoise tracer") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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