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2022-06-14tracing: Avoid adding tracer option before update_tracer_optionsMark-PK Tsai
[ Upstream commit ef9188bcc6ca1d8a2ad83e826b548e6820721061 ] To prepare for support asynchronous tracer_init_tracefs initcall, avoid calling create_trace_option_files before __update_tracer_options. Otherwise, create_trace_option_files will show warning because some tracers in trace_types list are already in tr->topts. For example, hwlat_tracer call register_tracer in late_initcall, and global_trace.dir is already created in tracing_init_dentry, hwlat_tracer will be put into tr->topts. Then if the __update_tracer_options is executed after hwlat_tracer registered, create_trace_option_files find that hwlat_tracer is already in tr->topts. Link: https://lkml.kernel.org/r/20220426122407.17042-2-mark-pk.tsai@mediatek.com Link: https://lore.kernel.org/lkml/20220322133339.GA32582@xsang-OptiPlex-9020/ Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14tracing: Fix sleeping function called from invalid context on RT kernelJun Miao
[ Upstream commit 12025abdc8539ed9d5014e2d647a3fd1bd3de5cd ] When setting bootparams="trace_event=initcall:initcall_start tp_printk=1" in the cmdline, the output_printk() was called, and the spin_lock_irqsave() was called in the atomic and irq disable interrupt context suitation. On the PREEMPT_RT kernel, these locks are replaced with sleepable rt-spinlock, so the stack calltrace will be triggered. Fix it by raw_spin_lock_irqsave when PREEMPT_RT and "trace_event=initcall:initcall_start tp_printk=1" enabled. BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0 preempt_count: 2, expected: 0 RCU nest depth: 0, expected: 0 Preemption disabled at: [<ffffffff8992303e>] try_to_wake_up+0x7e/0xba0 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.1-rt17+ #19 34c5812404187a875f32bee7977f7367f9679ea7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x60/0x8c dump_stack+0x10/0x12 __might_resched.cold+0x11d/0x155 rt_spin_lock+0x40/0x70 trace_event_buffer_commit+0x2fa/0x4c0 ? map_vsyscall+0x93/0x93 trace_event_raw_event_initcall_start+0xbe/0x110 ? perf_trace_initcall_finish+0x210/0x210 ? probe_sched_wakeup+0x34/0x40 ? ttwu_do_wakeup+0xda/0x310 ? trace_hardirqs_on+0x35/0x170 ? map_vsyscall+0x93/0x93 do_one_initcall+0x217/0x3c0 ? trace_event_raw_event_initcall_level+0x170/0x170 ? push_cpu_stop+0x400/0x400 ? cblist_init_generic+0x241/0x290 kernel_init_freeable+0x1ac/0x347 ? _raw_spin_unlock_irq+0x65/0x80 ? rest_init+0xf0/0xf0 kernel_init+0x1e/0x150 ret_from_fork+0x22/0x30 </TASK> Link: https://lkml.kernel.org/r/20220419013910.894370-1-jun.miao@intel.com Signed-off-by: Jun Miao <jun.miao@intel.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-16tracing: Ensure trace buffer is at least 4096 bytes largeSven Schnelle
[ Upstream commit 7acf3a127bb7c65ff39099afd78960e77b2ca5de ] Booting the kernel with 'trace_buf_size=1' give a warning at boot during the ftrace selftests: [ 0.892809] Running postponed tracer tests: [ 0.892893] Testing tracer function: [ 0.901899] Callback from call_rcu_tasks_trace() invoked. [ 0.983829] Callback from call_rcu_tasks_rude() invoked. [ 1.072003] .. bad ring buffer .. corrupted trace buffer .. [ 1.091944] Callback from call_rcu_tasks() invoked. [ 1.097695] PASSED [ 1.097701] Testing dynamic ftrace: .. filter failed count=0 ..FAILED! [ 1.353474] ------------[ cut here ]------------ [ 1.353478] WARNING: CPU: 0 PID: 1 at kernel/trace/trace.c:1951 run_tracer_selftest+0x13c/0x1b0 Therefore enforce a minimum of 4096 bytes to make the selftest pass. Link: https://lkml.kernel.org/r/20220214134456.1751749-1-svens@linux.ibm.com Signed-off-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-03-08tracing: Fix return value of __setup handlersRandy Dunlap
commit 1d02b444b8d1345ea4708db3bab4db89a7784b55 upstream. __setup() handlers should generally return 1 to indicate that the boot options have been handled. Using invalid option values causes the entire kernel boot option string to be reported as Unknown and added to init's environment strings, polluting it. Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc6 kprobe_event=p,syscall_any,$arg1 trace_options=quiet trace_clock=jiffies", will be passed to user space. Run /sbin/init as init process with arguments: /sbin/init with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc6 kprobe_event=p,syscall_any,$arg1 trace_options=quiet trace_clock=jiffies Return 1 from the __setup() handlers so that init's environment is not polluted with kernel boot options. Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Link: https://lkml.kernel.org/r/20220303031744.32356-1-rdunlap@infradead.org Cc: stable@vger.kernel.org Fixes: 7bcfaf54f591 ("tracing: Add trace_options kernel command line parameter") Fixes: e1e232ca6b8f ("tracing: Add trace_clock=<clock> kernel parameter") Fixes: 970988e19eb0 ("tracing/kprobe: Add kprobe_event= boot parameter") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-23tracing: Fix tp_printk option related with tp_printk_stop_on_bootJaeSang Yoo
[ Upstream commit 3203ce39ac0b2a57a84382ec184c7d4a0bede175 ] The kernel parameter "tp_printk_stop_on_boot" starts with "tp_printk" which is the same as another kernel parameter "tp_printk". If "tp_printk" setup is called before the "tp_printk_stop_on_boot", it will override the latter and keep it from being set. This is similar to other kernel parameter issues, such as: Commit 745a600cf1a6 ("um: console: Ignore console= option") or init/do_mounts.c:45 (setup function of "ro" kernel param) Fix it by checking for a "_" right after the "tp_printk" and if that exists do not process the parameter. Link: https://lkml.kernel.org/r/20220208195421.969326-1-jsyoo5b@gmail.com Signed-off-by: JaeSang Yoo <jsyoo5b@gmail.com> [ Fixed up change log and added space after if condition ] Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-01tracing: Don't inc err_log entry count if entry allocation failsTom Zanussi
commit 67ab5eb71b37b55f7c5522d080a1b42823351776 upstream. tr->n_err_log_entries should only be increased if entry allocation succeeds. Doing it when it fails won't cause any problems other than wasting an entry, but should be fixed anyway. Link: https://lkml.kernel.org/r/cad1ab28f75968db0f466925e7cba5970cec6c29.1643319703.git.zanussi@kernel.org Cc: stable@vger.kernel.org Fixes: 2f754e771b1a6 ("tracing: Don't inc err_log entry count if entry allocation fails") Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-11tracing: Tag trace_percpu_buffer as a percpu pointerNaveen N. Rao
commit f28439db470cca8b6b082239314e9fd10bd39034 upstream. Tag trace_percpu_buffer as a percpu pointer to resolve warnings reported by sparse: /linux/kernel/trace/trace.c:3218:46: warning: incorrect type in initializer (different address spaces) /linux/kernel/trace/trace.c:3218:46: expected void const [noderef] __percpu *__vpp_verify /linux/kernel/trace/trace.c:3218:46: got struct trace_buffer_struct * /linux/kernel/trace/trace.c:3234:9: warning: incorrect type in initializer (different address spaces) /linux/kernel/trace/trace.c:3234:9: expected void const [noderef] __percpu *__vpp_verify /linux/kernel/trace/trace.c:3234:9: got int * Link: https://lkml.kernel.org/r/ebabd3f23101d89cb75671b68b6f819f5edc830b.1640255304.git.naveen.n.rao@linux.vnet.ibm.com Cc: stable@vger.kernel.org Reported-by: kernel test robot <lkp@intel.com> Fixes: 07d777fe8c398 ("tracing: Add percpu buffers for trace_printk()") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-11tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()Naveen N. Rao
commit 823e670f7ed616d0ce993075c8afe0217885f79d upstream. With the new osnoise tracer, we are seeing the below splat: Kernel attempted to read user page (c7d880000) - exploit attempt? (uid: 0) BUG: Unable to handle kernel data access on read at 0xc7d880000 Faulting instruction address: 0xc0000000002ffa10 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries ... NIP [c0000000002ffa10] __trace_array_vprintk.part.0+0x70/0x2f0 LR [c0000000002ff9fc] __trace_array_vprintk.part.0+0x5c/0x2f0 Call Trace: [c0000008bdd73b80] [c0000000001c49cc] put_prev_task_fair+0x3c/0x60 (unreliable) [c0000008bdd73be0] [c000000000301430] trace_array_printk_buf+0x70/0x90 [c0000008bdd73c00] [c0000000003178b0] trace_sched_switch_callback+0x250/0x290 [c0000008bdd73c90] [c000000000e70d60] __schedule+0x410/0x710 [c0000008bdd73d40] [c000000000e710c0] schedule+0x60/0x130 [c0000008bdd73d70] [c000000000030614] interrupt_exit_user_prepare_main+0x264/0x270 [c0000008bdd73de0] [c000000000030a70] syscall_exit_prepare+0x150/0x180 [c0000008bdd73e10] [c00000000000c174] system_call_vectored_common+0xf4/0x278 osnoise tracer on ppc64le is triggering osnoise_taint() for negative duration in get_int_safe_duration() called from trace_sched_switch_callback()->thread_exit(). The problem though is that the check for a valid trace_percpu_buffer is incorrect in get_trace_buf(). The check is being done after calculating the pointer for the current cpu, rather than on the main percpu pointer. Fix the check to be against trace_percpu_buffer. Link: https://lkml.kernel.org/r/a920e4272e0b0635cf20c444707cbce1b2c8973d.1640255304.git.naveen.n.rao@linux.vnet.ibm.com Cc: stable@vger.kernel.org Fixes: e2ace001176dc9 ("tracing: Choose static tp_printk buffer by explicit nesting count") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-08-12tracing: Fix NULL pointer dereference in start_creatingKamal Agrawal
commit ff41c28c4b54052942180d8b3f49e75f1445135a upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-28tracing/histogram: Rename "cpu" to "common_cpu"Steven Rostedt (VMware)
commit 1e3bac71c5053c99d438771fc9fa5082ae5d90aa upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-19tracing: Resize tgid_map to pid_max, not PID_MAX_DEFAULTPaul Burton
commit 4030a6e6a6a4a42ff8c18414c9e0c93e24cc70b8 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-19tracing: Simplify & fix saved_tgids logicPaul Burton
commit b81b3e959adb107cd5b36c7dc5ba1364bbd31eb2 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-23tracing: Do not stop recording comms if the trace file is being readSteven Rostedt (VMware)
commit 4fdd595e4f9a1ff6d93ec702eaecae451cfc6591 upstream. A while ago, when the "trace" file was opened, tracing was stopped, and code was added to stop recording the comms to saved_cmdlines, for mapping of the pids to the task name. Code has been added that only records the comm if a trace event occurred, and there's no reason to not trace it if the trace file is opened. Cc: stable@vger.kernel.org Fixes: 7ffbd48d5cab2 ("tracing: Cache comms only after an event occurred") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-23tracing: Do not stop recording cmdlines when tracing is offSteven Rostedt (VMware)
commit 85550c83da421fb12dc1816c45012e1e638d2b38 upstream. The saved_cmdlines is used to map pids to the task name, such that the output of the tracing does not just show pids, but also gives a human readable name for the task. If the name is not mapped, the output looks like this: <...>-1316 [005] ...2 132.044039: ... Instead of this: gnome-shell-1316 [005] ...2 132.044039: ... The names are updated when tracing is running, but are skipped if tracing is stopped. Unfortunately, this stops the recording of the names if the top level tracer is stopped, and not if there's other tracers active. The recording of a name only happens when a new event is written into a ring buffer, so there is no need to test if tracing is on or not. If tracing is off, then no event is written and no need to test if tracing is off or not. Remove the check, as it hides the names of tasks for events in the instance buffers. Cc: stable@vger.kernel.org Fixes: 7ffbd48d5cab2 ("tracing: Cache comms only after an event occurred") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-16tracing: Correct the length check which causes memory corruptionLiangyan
commit 3e08a9f9760f4a70d633c328a76408e62d6f80a3 upstream. We've suffered from severe kernel crashes due to memory corruption on our production environment, like, Call Trace: [1640542.554277] general protection fault: 0000 [#1] SMP PTI [1640542.554856] CPU: 17 PID: 26996 Comm: python Kdump: loaded Tainted:G [1640542.556629] RIP: 0010:kmem_cache_alloc+0x90/0x190 [1640542.559074] RSP: 0018:ffffb16faa597df8 EFLAGS: 00010286 [1640542.559587] RAX: 0000000000000000 RBX: 0000000000400200 RCX: 0000000006e931bf [1640542.560323] RDX: 0000000006e931be RSI: 0000000000400200 RDI: ffff9a45ff004300 [1640542.560996] RBP: 0000000000400200 R08: 0000000000023420 R09: 0000000000000000 [1640542.561670] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff9a20608d [1640542.562366] R13: ffff9a45ff004300 R14: ffff9a45ff004300 R15: 696c662f65636976 [1640542.563128] FS: 00007f45d7c6f740(0000) GS:ffff9a45ff840000(0000) knlGS:0000000000000000 [1640542.563937] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [1640542.564557] CR2: 00007f45d71311a0 CR3: 000000189d63e004 CR4: 00000000003606e0 [1640542.565279] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [1640542.566069] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [1640542.566742] Call Trace: [1640542.567009] anon_vma_clone+0x5d/0x170 [1640542.567417] __split_vma+0x91/0x1a0 [1640542.567777] do_munmap+0x2c6/0x320 [1640542.568128] vm_munmap+0x54/0x70 [1640542.569990] __x64_sys_munmap+0x22/0x30 [1640542.572005] do_syscall_64+0x5b/0x1b0 [1640542.573724] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [1640542.575642] RIP: 0033:0x7f45d6e61e27 James Wang has reproduced it stably on the latest 4.19 LTS. After some debugging, we finally proved that it's due to ftrace buffer out-of-bound access using a debug tool as follows: [ 86.775200] BUG: Out-of-bounds write at addr 0xffff88aefe8b7000 [ 86.780806] no_context+0xdf/0x3c0 [ 86.784327] __do_page_fault+0x252/0x470 [ 86.788367] do_page_fault+0x32/0x140 [ 86.792145] page_fault+0x1e/0x30 [ 86.795576] strncpy_from_unsafe+0x66/0xb0 [ 86.799789] fetch_memory_string+0x25/0x40 [ 86.804002] fetch_deref_string+0x51/0x60 [ 86.808134] kprobe_trace_func+0x32d/0x3a0 [ 86.812347] kprobe_dispatcher+0x45/0x50 [ 86.816385] kprobe_ftrace_handler+0x90/0xf0 [ 86.820779] ftrace_ops_assist_func+0xa1/0x140 [ 86.825340] 0xffffffffc00750bf [ 86.828603] do_sys_open+0x5/0x1f0 [ 86.832124] do_syscall_64+0x5b/0x1b0 [ 86.835900] entry_SYSCALL_64_after_hwframe+0x44/0xa9 commit b220c049d519 ("tracing: Check length before giving out the filter buffer") adds length check to protect trace data overflow introduced in 0fc1b09ff1ff, seems that this fix can't prevent overflow entirely, the length check should also take the sizeof entry->array[0] into account, since this array[0] is filled the length of trace data and occupy addtional space and risk overflow. Link: https://lkml.kernel.org/r/20210607125734.1770447-1-liangyan.peng@linux.alibaba.com Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@redhat.com> Cc: Xunlei Pang <xlpang@linux.alibaba.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: b220c049d519 ("tracing: Check length before giving out the filter buffer") Reviewed-by: Xunlei Pang <xlpang@linux.alibaba.com> Reviewed-by: yinbinbin <yinbinbin@alibabacloud.com> Reviewed-by: Wetp Zhang <wetp.zy@linux.alibaba.com> Tested-by: James Wang <jnwang@linux.alibaba.com> Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11tracing: Map all PIDs to command linesSteven Rostedt (VMware)
commit 785e3c0a3a870e72dc530856136ab4c8dd207128 upstream. The default max PID is set by PID_MAX_DEFAULT, and the tracing infrastructure uses this number to map PIDs to the comm names of the tasks, such output of the trace can show names from the recorded PIDs in the ring buffer. This mapping is also exported to user space via the "saved_cmdlines" file in the tracefs directory. But currently the mapping expects the PIDs to be less than PID_MAX_DEFAULT, which is the default maximum and not the real maximum. Recently, systemd will increases the maximum value of a PID on the system, and when tasks are traced that have a PID higher than PID_MAX_DEFAULT, its comm is not recorded. This leads to the entire trace to have "<...>" as the comm name, which is pretty useless. Instead, keep the array mapping the size of PID_MAX_DEFAULT, but instead of just mapping the index to the comm, map a mask of the PID (PID_MAX_DEFAULT - 1) to the comm, and find the full PID from the map_cmdline_to_pid array (that already exists). This bug goes back to the beginning of ftrace, but hasn't been an issue until user space started increasing the maximum value of PIDs. Link: https://lkml.kernel.org/r/20210427113207.3c601884@gandalf.local.home Cc: stable@vger.kernel.org Fixes: bc0c38d139ec7 ("ftrace: latency tracer infrastructure") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-07tracing: Fix stack trace event sizeSteven Rostedt (VMware)
commit 9deb193af69d3fd6dd8e47f292b67c805a787010 upstream. Commit cbc3b92ce037 fixed an issue to modify the macros of the stack trace event so that user space could parse it properly. Originally the stack trace format to user space showed that the called stack was a dynamic array. But it is not actually a dynamic array, in the way that other dynamic event arrays worked, and this broke user space parsing for it. The update was to make the array look to have 8 entries in it. Helper functions were added to make it parse it correctly, as the stack was dynamic, but was determined by the size of the event stored. Although this fixed user space on how it read the event, it changed the internal structure used for the stack trace event. It changed the array size from [0] to [8] (added 8 entries). This increased the size of the stack trace event by 8 words. The size reserved on the ring buffer was the size of the stack trace event plus the number of stack entries found in the stack trace. That commit caused the amount to be 8 more than what was needed because it did not expect the caller field to have any size. This produced 8 entries of garbage (and reading random data) from the stack trace event: <idle>-0 [002] d... 1976396.837549: <stack trace> => trace_event_raw_event_sched_switch => __traceiter_sched_switch => __schedule => schedule_idle => do_idle => cpu_startup_entry => secondary_startup_64_no_verify => 0xc8c5e150ffff93de => 0xffff93de => 0 => 0 => 0xc8c5e17800000000 => 0x1f30affff93de => 0x00000004 => 0x200000000 Instead, subtract the size of the caller field from the size of the event to make sure that only the amount needed to store the stack trace is reserved. Link: https://lore.kernel.org/lkml/your-ad-here.call-01617191565-ext-9692@work.hours/ Cc: stable@vger.kernel.org Fixes: cbc3b92ce037 ("tracing: Set kernel_stack's caller size properly") Reported-by: Vasily Gorbik <gor@linux.ibm.com> Tested-by: Vasily Gorbik <gor@linux.ibm.com> Acked-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-17tracing: Check length before giving out the filter bufferSteven Rostedt (VMware)
commit b220c049d5196dd94d992dd2dc8cba1a5e6123bf upstream. When filters are used by trace events, a page is allocated on each CPU and used to copy the trace event fields to this page before writing to the ring buffer. The reason to use the filter and not write directly into the ring buffer is because a filter may discard the event and there's more overhead on discarding from the ring buffer than the extra copy. The problem here is that there is no check against the size being allocated when using this page. If an event asks for more than a page size while being filtered, it will get only a page, leading to the caller writing more that what was allocated. Check the length of the request, and if it is more than PAGE_SIZE minus the header default back to allocating from the ring buffer directly. The ring buffer may reject the event if its too big anyway, but it wont overflow. Link: https://lore.kernel.org/ath10k/1612839593-2308-1-git-send-email-wgong@codeaurora.org/ Cc: stable@vger.kernel.org Fixes: 0fc1b09ff1ff4 ("tracing: Use temp buffer when filtering events") Reported-by: Wen Gong <wgong@codeaurora.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30tracing: Disable ftrace selftests when any tracer is runningMasami Hiramatsu
commit 60efe21e5976d3d4170a8190ca76a271d6419754 upstream. Disable ftrace selftests when any tracer (kernel command line options like ftrace=, trace_events=, kprobe_events=, and boot-time tracing) starts running because selftest can disturb it. Currently ftrace= and trace_events= are checked, but kprobe_events has a different flag, and boot-time tracing didn't checked. This unifies the disabled flag and all of those boot-time tracing features sets the flag. This also fixes warnings on kprobe-event selftest (CONFIG_FTRACE_STARTUP_TEST=y and CONFIG_KPROBE_EVENTS=y) with boot-time tracing (ftrace.event.kprobes.EVENT.probes) like below; [ 59.803496] trace_kprobe: Testing kprobe tracing: [ 59.804258] ------------[ cut here ]------------ [ 59.805682] WARNING: CPU: 3 PID: 1 at kernel/trace/trace_kprobe.c:1987 kprobe_trace_self_tests_ib [ 59.806944] Modules linked in: [ 59.807335] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc7+ #172 [ 59.808029] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/204 [ 59.808999] RIP: 0010:kprobe_trace_self_tests_init+0x5f/0x42b [ 59.809696] Code: e8 03 00 00 48 c7 c7 30 8e 07 82 e8 6d 3c 46 ff 48 c7 c6 00 b2 1a 81 48 c7 c7 7 [ 59.812439] RSP: 0018:ffffc90000013e78 EFLAGS: 00010282 [ 59.813038] RAX: 00000000ffffffef RBX: 0000000000000000 RCX: 0000000000049443 [ 59.813780] RDX: 0000000000049403 RSI: 0000000000049403 RDI: 000000000002deb0 [ 59.814589] RBP: ffffc90000013e90 R08: 0000000000000001 R09: 0000000000000001 [ 59.815349] R10: 0000000000000001 R11: 0000000000000000 R12: 00000000ffffffef [ 59.816138] R13: ffff888004613d80 R14: ffffffff82696940 R15: ffff888004429138 [ 59.816877] FS: 0000000000000000(0000) GS:ffff88807dcc0000(0000) knlGS:0000000000000000 [ 59.817772] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 59.818395] CR2: 0000000001a8dd38 CR3: 0000000002222000 CR4: 00000000000006a0 [ 59.819144] Call Trace: [ 59.819469] ? init_kprobe_trace+0x6b/0x6b [ 59.819948] do_one_initcall+0x5f/0x300 [ 59.820392] ? rcu_read_lock_sched_held+0x4f/0x80 [ 59.820916] kernel_init_freeable+0x22a/0x271 [ 59.821416] ? rest_init+0x241/0x241 [ 59.821841] kernel_init+0xe/0x10f [ 59.822251] ret_from_fork+0x22/0x30 [ 59.822683] irq event stamp: 16403349 [ 59.823121] hardirqs last enabled at (16403359): [<ffffffff810db81e>] console_unlock+0x48e/0x580 [ 59.824074] hardirqs last disabled at (16403368): [<ffffffff810db786>] console_unlock+0x3f6/0x580 [ 59.825036] softirqs last enabled at (16403200): [<ffffffff81c0033a>] __do_softirq+0x33a/0x484 [ 59.825982] softirqs last disabled at (16403087): [<ffffffff81a00f02>] asm_call_irq_on_stack+0x10 [ 59.827034] ---[ end trace 200c544775cdfeb3 ]--- [ 59.827635] trace_kprobe: error on probing function entry. Link: https://lkml.kernel.org/r/160741764955.3448999.3347769358299456915.stgit@devnote2 Fixes: 4d655281eb1b ("tracing/boot Add kprobe event support") Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tracing: Fix userstacktrace option for instancesSteven Rostedt (VMware)
When the instances were able to use their own options, the userstacktrace option was left hardcoded for the top level. This made the instance userstacktrace option bascially into a nop, and will confuse users that set it, but nothing happens (I was confused when it happened to me!) Cc: stable@vger.kernel.org Fixes: 16270145ce6b ("tracing: Add trace options for core options to instances") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-30tracing: Fix alignment of static bufferMinchan Kim
With 5.9 kernel on ARM64, I found ftrace_dump output was broken but it had no problem with normal output "cat /sys/kernel/debug/tracing/trace". With investigation, it seems coping the data into temporal buffer seems to break the align binary printf expects if the static buffer is not aligned with 4-byte. IIUC, get_arg in bstr_printf expects that args has already right align to be decoded and seq_buf_bprintf says ``the arguments are saved in a 32bit word array that is defined by the format string constraints``. So if we don't keep the align under copy to temporal buffer, the output will be broken by shifting some bytes. This patch fixes it. Link: https://lkml.kernel.org/r/20201125225654.1618966-1-minchan@kernel.org Cc: <stable@vger.kernel.org> Fixes: 8e99cf91b99bb ("tracing: Do not allocate buffer in trace_find_next_entry() in atomic") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-02tracing: Fix the checking of stackidx in __ftrace_trace_stackQiujun Huang
The array size is FTRACE_KSTACK_NESTING, so the index FTRACE_KSTACK_NESTING is illegal too. And fix two typos by the way. Link: https://lkml.kernel.org/r/20201031085714.2147-1-hqjagain@gmail.com Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-02tracing: Fix out of bounds write in get_trace_bufQiujun Huang
The nesting count of trace_printk allows for 4 levels of nesting. The nesting counter starts at zero and is incremented before being used to retrieve the current context's buffer. But the index to the buffer uses the nesting counter after it was incremented, and not its original number, which in needs to do. Link: https://lkml.kernel.org/r/20201029161905.4269-1-hqjagain@gmail.com Cc: stable@vger.kernel.org Fixes: 3d9622c12c887 ("tracing: Add barrier to trace_printk() buffer nesting modification") Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-15Merge tag 'trace-v5.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "Updates for tracing and bootconfig: - Add support for "bool" type in synthetic events - Add per instance tracing for bootconfig - Support perf-style return probe ("SYMBOL%return") in kprobes and uprobes - Allow for kprobes to be enabled earlier in boot up - Added tracepoint helper function to allow testing if tracepoints are enabled in headers - Synthetic events can now have dynamic strings (variable length) - Various fixes and cleanups" * tag 'trace-v5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (58 commits) tracing: support "bool" type in synthetic trace events selftests/ftrace: Add test case for synthetic event syntax errors tracing: Handle synthetic event array field type checking correctly selftests/ftrace: Change synthetic event name for inter-event-combined test tracing: Add synthetic event error logging tracing: Check that the synthetic event and field names are legal tracing: Move is_good_name() from trace_probe.h to trace.h tracing: Don't show dynamic string internals in synthetic event description tracing: Fix some typos in comments tracing/boot: Add ftrace.instance.*.alloc_snapshot option tracing: Fix race in trace_open and buffer resize call tracing: Check return value of __create_val_fields() before using its result tracing: Fix synthetic print fmt check for use of __get_str() tracing: Remove a pointless assignment ftrace: ftrace_global_list is renamed to ftrace_ops_list ftrace: Format variable declarations of ftrace_allocate_records ftrace: Simplify the calculation of page number for ftrace_page->records ftrace: Simplify the dyn_ftrace->flags macro ftrace: Simplify the hash calculation ftrace: Use fls() to get the bits for dup_hash() ...
2020-10-15Merge tag 'char-misc-5.10-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big set of char, misc, and other assorted driver subsystem patches for 5.10-rc1. There's a lot of different things in here, all over the drivers/ directory. Some summaries: - soundwire driver updates - habanalabs driver updates - extcon driver updates - nitro_enclaves new driver - fsl-mc driver and core updates - mhi core and bus updates - nvmem driver updates - eeprom driver updates - binder driver updates and fixes - vbox minor bugfixes - fsi driver updates - w1 driver updates - coresight driver updates - interconnect driver updates - misc driver updates - other minor driver updates All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (396 commits) binder: fix UAF when releasing todo list docs: w1: w1_therm: Fix broken xref, mistakes, clarify text misc: Kconfig: fix a HISI_HIKEY_USB dependency LSM: Fix type of id parameter in kernel_post_load_data prototype misc: Kconfig: add a new dependency for HISI_HIKEY_USB firmware_loader: fix a kernel-doc markup w1: w1_therm: make w1_poll_completion static binder: simplify the return expression of binder_mmap test_firmware: Test partial read support firmware: Add request_partial_firmware_into_buf() firmware: Store opt_flags in fw_priv fs/kernel_file_read: Add "offset" arg for partial reads IMA: Add support for file reads without contents LSM: Add "contents" flag to kernel_read_file hook module: Call security_kernel_post_load_data() firmware_loader: Use security_post_load_data() LSM: Introduce kernel_post_load_data() hook fs/kernel_read_file: Add file_size output argument fs/kernel_read_file: Switch buffer size arg to size_t fs/kernel_read_file: Remove redundant size argument ...
2020-10-15tracing: Fix some typos in commentsQiujun Huang
s/wihin/within/ s/retrieven/retrieved/ s/suppport/support/ s/wil/will/ s/accidently/accidentally/ s/if the if the/if the/ Link: https://lkml.kernel.org/r/20201010140924.3809-1-hqjagain@gmail.com Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-12Merge tag 'core-static_call-2020-10-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull static call support from Ingo Molnar: "This introduces static_call(), which is the idea of static_branch() applied to indirect function calls. Remove a data load (indirection) by modifying the text. They give the flexibility of function pointers, but with better performance. (This is especially important for cases where retpolines would otherwise be used, as retpolines can be pretty slow.) API overview: DECLARE_STATIC_CALL(name, func); DEFINE_STATIC_CALL(name, func); DEFINE_STATIC_CALL_NULL(name, typename); static_call(name)(args...); static_call_cond(name)(args...); static_call_update(name, func); x86 is supported via text patching, otherwise basic indirect calls are used, with function pointers. There's a second variant using inline code patching, inspired by jump-labels, implemented on x86 as well. The new APIs are utilized in the x86 perf code, a heavy user of function pointers, where static calls speed up the PMU handler by 4.2% (!). The generic implementation is not really excercised on other architectures, outside of the trivial test_static_call_init() self-test" * tag 'core-static_call-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) static_call: Fix return type of static_call_init tracepoint: Fix out of sync data passing by static caller tracepoint: Fix overly long tracepoint names x86/perf, static_call: Optimize x86_pmu methods tracepoint: Optimize using static_call() static_call: Allow early init static_call: Add some validation static_call: Handle tail-calls static_call: Add static_call_cond() x86/alternatives: Teach text_poke_bp() to emulate RET static_call: Add simple self-test for static calls x86/static_call: Add inline static call implementation for x86-64 x86/static_call: Add out-of-line static call implementation static_call: Avoid kprobes on inline static_call()s static_call: Add inline static call infrastructure static_call: Add basic static call infrastructure compiler.h: Make __ADDRESSABLE() symbol truly unique jump_label,module: Fix module lifetime for __jump_label_mod_text_reserved() module: Properly propagate MODULE_STATE_COMING failure module: Fix up module_notifier return values ...
2020-10-08tracing: Remove a pointless assignmentSudip Mukherjee
The variable 'len' has been assigned a value but is not used after that. So, remove the assignement. Link: https://lkml.kernel.org/r/20200930184303.22896-1-sudipm.mukherjee@gmail.com Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-08tracing: Add README information for synthetic_events fileTom Zanussi
Add an entry with a basic description of events/synthetic_events along with a simple example. Link: https://lkml.kernel.org/r/3c7f178cf95aaeebc01eda7d95600dd937233eb7.1601848695.git.zanussi@kernel.org Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-10-05tracing: Add trace_export support for trace_markerTingwei Zhang
Add the support to route trace_marker buffer to other destination via trace_export. Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lore.kernel.org/r/20201005071319.78508-5-alexander.shishkin@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05tracing: Add trace_export support for event traceTingwei Zhang
Only function traces can be exported to other destinations currently. This patch exports event trace as well. Move trace export related function to the beginning of file so other trace can call trace_process_export() to export. Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lore.kernel.org/r/20201005071319.78508-4-alexander.shishkin@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-05tracing: Add flag to control different tracesTingwei Zhang
More traces like event trace or trace marker will be supported. Add flag for difference traces, so that they can be controlled separately. Move current function trace to it's own flag instead of global ftrace enable flag. Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lore.kernel.org/r/20201005071319.78508-3-alexander.shishkin@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-29tracing: Fix trace_find_next_entry() accounting of temp buffer sizeSteven Rostedt (VMware)
The temp buffer size variable for trace_find_next_entry() was incorrectly being updated when the size did not change. The temp buffer size should only be updated when it is reallocated. This is mostly an issue when used with ftrace_dump(). That's because ftrace_dump() can not allocate a new buffer, and instead uses a temporary buffer with a fix size. But the variable that keeps track of that size is incorrectly updated with each call, and it could fall into the path that would try to reallocate the buffer and produce a warning. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1601 at kernel/trace/trace.c:3548 trace_find_next_entry+0xd0/0xe0 Modules linked in [..] CPU: 1 PID: 1601 Comm: bash Not tainted 5.9.0-rc5-test+ #521 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 RIP: 0010:trace_find_next_entry+0xd0/0xe0 Code: 40 21 00 00 4c 89 e1 31 d2 4c 89 ee 48 89 df e8 c6 9e ff ff 89 ab 54 21 00 00 5b 5d 41 5c 41 5d c3 48 63 d5 eb bf 31 c0 eb f0 <0f> 0b 48 63 d5 eb b4 66 0f 1f 84 00 00 00 00 00 53 48 8d 8f 60 21 RSP: 0018:ffff95a4f2e8bd70 EFLAGS: 00010046 RAX: ffffffff96679fc0 RBX: ffffffff97910de0 RCX: ffffffff96679fc0 RDX: ffff95a4f2e8bd98 RSI: ffff95a4ee321098 RDI: ffffffff97913000 RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000046 R12: ffff95a4f2e8bd98 R13: 0000000000000000 R14: ffff95a4ee321098 R15: 00000000009aa301 FS: 00007f8565484740(0000) GS:ffff95a55aa40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055876bd43d90 CR3: 00000000b76e6003 CR4: 00000000001706e0 Call Trace: trace_print_lat_context+0x58/0x2d0 ? cpumask_next+0x16/0x20 print_trace_line+0x1a4/0x4f0 ftrace_dump.cold+0xad/0x12c __handle_sysrq.cold+0x51/0x126 write_sysrq_trigger+0x3f/0x4a proc_reg_write+0x53/0x80 vfs_write+0xca/0x210 ksys_write+0x70/0xf0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f8565579487 Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007ffd40707948 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f8565579487 RDX: 0000000000000002 RSI: 000055876bd74de0 RDI: 0000000000000001 RBP: 000055876bd74de0 R08: 000000000000000a R09: 0000000000000001 R10: 000055876bdec280 R11: 0000000000000246 R12: 0000000000000002 R13: 00007f856564a500 R14: 0000000000000002 R15: 00007f856564a700 irq event stamp: 109958 ---[ end trace 7aab5b7e51484b00 ]--- Not only fix the updating of the temp buffer, but also do not free the temp buffer before a new buffer is allocated (there's no reason to not continue to use the current temp buffer if an allocation fails). Cc: stable@vger.kernel.org Fixes: 8e99cf91b99bb ("tracing: Do not allocate buffer in trace_find_next_entry() in atomic") Reported-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-25tracing/boot: Initialize per-instance event list in early bootMasami Hiramatsu
Initialize per-instance event list in early boot time (before initializing instance directory on tracefs). This fixes boot-time tracing to correctly handle the boot-time per-instance settings. Link: https://lkml.kernel.org/r/160096560826.182763.17110991546046128881.stgit@devnote2 Fixes: 4114fbfd02f1 ("tracing: Enable creating new instance early boot") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21tracing: Enable creating new instance early bootMasami Hiramatsu
Enable creating new trace_array instance in early boot stage. If the instances directory is not created, postpone it until the tracefs is initialized. Link: https://lkml.kernel.org/r/159974154763.478751.6289753509587233103.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21tracing/uprobes: Support perf-style return probeMasami Hiramatsu
Support perf-style return probe ("SYMBOL%return") for uprobe events as same as kprobe events does. Link: https://lkml.kernel.org/r/159972814601.428528.7641183316212425445.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21tracing/kprobes: Support perf-style return probeMasami Hiramatsu
Support perf-style return probe ("SYMBOL%return") for kprobe events. This will allow boot-time tracing user to define a return probe event. Link: https://lkml.kernel.org/r/159972813535.428528.4437029657208468954.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21tracing: remove a pointless assignmentDan Carpenter
The "tr" is a stack variable so setting it to NULL before a return is a no-op. Delete the assignment. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21tracing: Use __this_cpu_read() in trace_buffered_event_enable()Xianting Tian
The code is executed with preemption disabled, so it's safe to use __this_cpu_read(). Link: https://lkml.kernel.org/r/20200813112803.12256-1-tian.xianting@h3c.com Signed-off-by: Xianting Tian <tian.xianting@h3c.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-21tracing: Delete repeated words in commentsRandy Dunlap
Drop repeated words in kernel/trace/. {and, the, not} Link: https://lkml.kernel.org/r/20200807033259.13778-1-rdunlap@infradead.org Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-18tracing: make tracing_init_dentry() returns an integer instead of a d_entry ↵Wei Yang
pointer Current tracing_init_dentry() return a d_entry pointer, while is not necessary. This function returns NULL on success or error on failure, which means there is no valid d_entry pointer return. Let's return 0 on success and negative value for error. Link: https://lkml.kernel.org/r/20200712011036.70948-5-richard.weiyang@linux.alibaba.com Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-18tracing: Make the space reserved for the pid widerSebastian Andrzej Siewior
For 64bit CONFIG_BASE_SMALL=0 systems PID_MAX_LIMIT is set by default to 4194304. During boot the kernel sets a new value based on number of CPUs but no lower than 32768. It is 1024 per CPU so with 128 CPUs the default becomes 131072 which needs six digits. This value can be increased during run time but must not exceed the initial upper limit. Systemd sometime after v241 sets it to the upper limit during boot. The result is that when the pid exceeds five digits, the trace output is a little hard to read because it is no longer properly padded (same like on big iron with 98+ CPUs). Increase the pid padding to seven digits. Link: https://lkml.kernel.org/r/20200904082331.dcdkrr3bkn3e4qlg@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-09-01module: Fix up module_notifier return valuesPeter Zijlstra
While auditing all module notifiers I noticed a whole bunch of fail wrt the return value. Notifiers have a 'special' return semantics. As is; NOTIFY_DONE vs NOTIFY_OK is a bit vague; but notifier_from_errno(0) results in NOTIFY_OK and NOTIFY_DONE has a comment that says "Don't care". From this I've used NOTIFY_DONE when the function completely ignores the callback and notifier_to_error() isn't used. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Reviewed-by: Robert Richter <rric@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20200818135804.385360407@infradead.org
2020-08-07Merge tag 'trace-v5.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - The biggest news in that the tracing ring buffer can now time events that interrupted other ring buffer events. Before this change, if an interrupt came in while recording another event, and that interrupt also had an event, those events would all have the same time stamp as the event it interrupted. Now, with the new design, those events will have a unique time stamp and rightfully display the time for those events that were recorded while interrupting another event. - Bootconfig how has an "override" operator that lets the users have a default config, but then add options to override the default. - A fix was made to properly filter function graph tracing to the ftrace PIDs. This came in at the end of the -rc cycle, and needs to be backported. - Several clean ups, performance updates, and minor fixes as well. * tag 'trace-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (39 commits) tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers kprobes: Fix compiler warning for !CONFIG_KPROBES_ON_FTRACE tracing: Use trace_sched_process_free() instead of exit() for pid tracing bootconfig: Fix to find the initargs correctly Documentation: bootconfig: Add bootconfig override operator tools/bootconfig: Add testcases for value override operator lib/bootconfig: Add override operator support kprobes: Remove show_registers() function prototype tracing/uprobe: Remove dead code in trace_uprobe_register() kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler ftrace: Fix ftrace_trace_task return value tracepoint: Use __used attribute definitions from compiler_attributes.h tracepoint: Mark __tracepoint_string's __used trace : Have tracing buffer info use kvzalloc instead of kzalloc tracing: Remove outdated comment in stack handling ftrace: Do not let direct or IPMODIFY ftrace_ops be added to module and set trampolines ftrace: Setup correct FTRACE_FL_REGS flags for module tracing/hwlat: Honor the tracing_cpumask tracing/hwlat: Drop the duplicate assignment in start_kthread() tracing: Save one trace_event->type by using __TRACE_LAST_TYPE ...
2020-08-07tracing: Add trace_array_init_printk() to initialize instance trace_printk() ↵Steven Rostedt (VMware)
buffers As trace_array_printk() used with not global instances will not add noise to the main buffer, they are OK to have in the kernel (unlike trace_printk()). This require the subsystem to create their own tracing instance, and the trace_array_printk() only writes into those instances. Add trace_array_init_printk() to initialize the trace_printk() buffers without printing out the WARNING message. Reported-by: Sean Paul <sean@poorly.run> Reviewed-by: Sean Paul <sean@poorly.run> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-08-06Merge tag 'fsnotify_for_v5.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull fsnotify updates from Jan Kara: - fanotify fix for softlockups when there are many queued events - performance improvement to reduce fsnotify overhead when not used - Amir's implementation of fanotify events with names. With these you can now efficiently monitor whole filesystem, eg to mirror changes to another machine. * tag 'fsnotify_for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (37 commits) fanotify: compare fsid when merging name event fsnotify: create method handle_inode_event() in fsnotify_operations fanotify: report parent fid + child fid fanotify: report parent fid + name + child fid fanotify: add support for FAN_REPORT_NAME fanotify: report events with parent dir fid to sb/mount/non-dir marks fanotify: add basic support for FAN_REPORT_DIR_FID fsnotify: remove check that source dentry is positive fsnotify: send event with parent/name info to sb/mount/non-dir marks audit: do not set FS_EVENT_ON_CHILD in audit marks mask inotify: do not set FS_EVENT_ON_CHILD in non-dir mark mask fsnotify: pass dir and inode arguments to fsnotify() fsnotify: create helper fsnotify_inode() fsnotify: send event to parent and child with single callback inotify: report both events on parent and child with single callback dnotify: report both events on parent and child with single callback fanotify: no external fh buffer in fanotify_name_event fanotify: use struct fanotify_info to parcel the variable size buffer fsnotify: add object type "child" to object type iterator fanotify: use FAN_EVENT_ON_CHILD as implicit flag on sb/mount/non-dir marks ...
2020-08-03trace : Have tracing buffer info use kvzalloc instead of kzallocZhaoyang Huang
High order memory stuff within trace could introduce OOM, use kvzalloc instead. Please find the bellowing for the call stack we run across in an android system. The scenario happens when traced_probes is woken up to get a large quantity of trace even if free memory is even higher than watermark_low.  traced_probes invoked oom-killer: gfp_mask=0x140c0c0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO), nodemask=(null), order=2, oom_score_adj=-1 traced_probes cpuset=system-background mems_allowed=0 CPU: 3 PID: 588 Comm: traced_probes Tainted: G W O 4.14.181 #1 Hardware name: Generic DT based system (unwind_backtrace) from [<c010d824>] (show_stack+0x20/0x24) (show_stack) from [<c0b2e174>] (dump_stack+0xa8/0xec) (dump_stack) from [<c027d584>] (dump_header+0x9c/0x220) (dump_header) from [<c027cfe4>] (oom_kill_process+0xc0/0x5c4) (oom_kill_process) from [<c027cb94>] (out_of_memory+0x220/0x310) (out_of_memory) from [<c02816bc>] (__alloc_pages_nodemask+0xff8/0x13a4) (__alloc_pages_nodemask) from [<c02a6a1c>] (kmalloc_order+0x30/0x48) (kmalloc_order) from [<c02a6a64>] (kmalloc_order_trace+0x30/0x118) (kmalloc_order_trace) from [<c0223d7c>] (tracing_buffers_open+0x50/0xfc) (tracing_buffers_open) from [<c02e6f58>] (do_dentry_open+0x278/0x34c) (do_dentry_open) from [<c02e70d0>] (vfs_open+0x50/0x70) (vfs_open) from [<c02f7c24>] (path_openat+0x5fc/0x169c) (path_openat) from [<c02f75c4>] (do_filp_open+0x94/0xf8) (do_filp_open) from [<c02e7650>] (do_sys_open+0x168/0x26c) (do_sys_open) from [<c02e77bc>] (SyS_openat+0x34/0x38) (SyS_openat) from [<c0108bc0>] (ret_fast_syscall+0x0/0x28) Link: https://lkml.kernel.org/r/1596155265-32365-1-git-send-email-zhaoyang.huang@unisoc.com Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-07-30tracing: Remove outdated comment in stack handlingVincent Whitchurch
This comment describes the behaviour before commit 2a820bf74918 ("tracing: Use percpu stack trace buffer more intelligently"). Since that commit, interrupts and NMIs do use the per-cpu stacks so the comment is no longer correct. Remove it. (Note that the FTRACE_STACK_SIZE mentioned in the comment has never existed, it probably should have said FTRACE_STACK_ENTRIES.) Link: https://lkml.kernel.org/r/20200727092840.18659-1-vincent.whitchurch@axis.com Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-07-27fsnotify: create helper fsnotify_inode()Amir Goldstein
Simple helper to consolidate biolerplate code. Link: https://lore.kernel.org/r/20200722125849.17418-5-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
2020-07-23tracefs: Remove unnecessary debug_fs checks.Peter Enderborg
This is a preparation for debugfs restricted mode. We don't need debugfs to trace, the removed check stop tracefs to work if debugfs is not initialised. We instead tries to automount within debugfs and relay on it's handling. The code path is to create a backward compatibility from when tracefs was part of debugfs, it is now standalone and does not need debugfs. When debugfs is in restricted it is compiled in but not active and return EPERM to clients and tracefs wont work if it assumes it is active it is compiled in kernel. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Peter Enderborg <peter.enderborg@sony.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20200716071511.26864-2-peter.enderborg@sony.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-02 23:54:11 +0000