user/sven/linux.git/arch/arm/kernel/stacktrace.c, branch v3.16.1

ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation

2014-05-30T00:12:32Z

When configure kprobe events of ftrace with "stacktrace" option enabled in arm, there is no stacktrace was recorded after the kprobe event was triggered. The root cause is no save_stack_trace_regs() function implemented. Implement the save_stack_trace_regs() function in arm, then ftrace will call this architecture-related function to record the stacktrace into ring buffer. After this fix, stacktrace can be recorded, for example: # mount -t debugfs nodev /sys/kernel/debug # echo "p:netrx net_rx_action" >> /sys/kernel/debug/tracing/kprobe_events # echo 1 > /sys/kernel/debug/tracing/events/kprobes/netrx/enable # echo 1 > /sys/kernel/debug/tracing/options/stacktrace # echo 1 > /sys/kernel/debug/tracing/tracing_on # ping 127.0.0.1 -c 1 # echo 0 > /sys/kernel/debug/tracing/tracing_on # cat /sys/kernel/debug/tracing/trace # tracer: nop # # entries-in-buffer/entries-written: 12/12 #P:1 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | <------ missing some entries ----------------> ping-1200 [000] dNs1 667.603250: netrx: (net_rx_action+0x0/0x1f8) ping-1200 [000] dNs1 667.604738: => net_rx_action => do_softirq => local_bh_enable => ip_finish_output => ip_output => ip_local_out => ip_send_skb => ip_push_pending_frames => raw_sendmsg => inet_sendmsg => sock_sendmsg => SyS_sendto => ret_fast_syscall Signed-off-by: Lin Yongting Acked-by: Steven Rostedt Signed-off-by: Russell King

ARM: stacktrace: include exception PC value in stacktrace output

2014-05-22T15:33:24Z

When we unwind through an exception stack, include the saved PC value into the stack trace: this fills in an otherwise missed functions from the trace (as indicated below): [] fec_enet_interrupt+0xa0/0xe8 [] handle_irq_event_percpu+0x68/0x228 [] handle_irq_event+0x4c/0x6c [] handle_fasteoi_irq+0xac/0x198 [] generic_handle_irq+0x4c/0x60 [] handle_IRQ+0x40/0x98 [] gic_handle_irq+0x30/0x64 [] __irq_svc+0x40/0x50 [] __do_softirq+0xe0/0x2fc <==== [] irq_exit+0xb0/0x100 [] handle_IRQ+0x44/0x98 [] gic_handle_irq+0x30/0x64 [] __irq_svc+0x40/0x50 [] arch_cpu_idle+0x30/0x38 <==== [] cpu_startup_entry+0xac/0x214 [] rest_init+0x68/0x80 [] start_kernel+0x2fc/0x358 Signed-off-by: Russell King

ARM: stacktrace: avoid listing stacktrace functions in stacktrace

2014-05-22T15:33:19Z

While debugging the FEC ethernet driver using stacktrace, it was noticed that the stacktraces always begin as follows: [] save_stack_trace_tsk+0x0/0x98 [] save_stack_trace+0x24/0x28 ... This is because the stack trace code includes the stack frames for itself. This is incorrect behaviour, and also leads to "skip" doing the wrong thing (which is the number of stack frames to avoid recording.) Perversely, it does the right thing when passed a non-current thread. Fix this by ensuring that we have a known constant number of frames above the main stack trace function, and always skip these. Cc: Signed-off-by: Russell King

ARM: 7913/1: fix framepointer check in unwind_frame

2013-12-09T23:24:33Z

This patch fixes corner case when (fp + 4) overflows unsigned long, for example: fp = 0xFFFFFFFF -> fp + 4 == 3. Cc: Signed-off-by: Konstantin Khlebnikov Signed-off-by: Russell King

arm: convert core files from module.h to export.h

2011-10-31T23:30:49Z

Many of the core ARM kernel files are not modules, but just including module.h for exporting symbols. Now these files can use the lighter footprint export.h for this role. There are probably lots more, but ARM files of mach-* and plat-* don't get coverage via a simple yesconfig build. They will have to be cleaned up and tested via using their respective configs. Signed-off-by: Paul Gortmaker

ARM: fix /proc/$PID/stack on SMP

2011-01-15T09:27:04Z

Rabin Vincent reports: | On SMP, this BUG() in save_stack_trace_tsk() can be easily triggered | from user space by reading /proc/$PID/stack, where $PID is any pid but | the current process: | | if (tsk != current) { | #ifdef CONFIG_SMP | /* | * What guarantees do we have here that 'tsk' | * is not running on another CPU? | */ | BUG(); | #else Fix this by replacing the BUG() with an entry to terminate the stack trace, returning an empty trace - I'd rather not expose the dwarf unwinder to a volatile stack of a running thread. Reported-by: Rabin Vincent Tested-by: Rabin Vincent Signed-off-by: Russell King

ARM: 6468/1: backtrace: fix calculation of thread stack base

2010-11-07T16:12:37Z

When unwinding stack frames we must take care not to unwind areas of memory that lie outside of the known extent of the stack. This patch fixes an incorrect calculation of the stack base where THREAD_SIZE is added to the stack pointer after it has already been aligned to this value. Since the ALIGN macro performs this addition internally, we end up overshooting the base by 8k. Acked-by: Catalin Marinas Signed-off-by: Will Deacon Signed-off-by: Russell King

[ARM] 5613/1: implement CALLER_ADDRESSx

2009-07-21T16:21:28Z

From: Uwe Kleine-König As __builtin_return_address(n) doesn't work for ARM with n > 0, the kernel needs its own implementation. This fixes many warnings saying: warning: unsupported argument to '__builtin_return_address' The new methods and walk_stackframe must not be instrumented because CALLER_ADDRESSx is used in the various tracers and tracing the tracer is a bad idea. What's currently missing is an implementation using unwind tables. This is not fatal though, it's just that the tracers don't get enough information to be really useful. Note that if both ARM_UNWIND and FRAME_POINTER are enabled, walk_stackframe uses unwind information. So in this case the same implementation is used as when FRAME_POINTER is disabled. Cc: Catalin Marinas Signed-off-by: Uwe Kleine-König Signed-off-by: Russell King

[ARM] 5382/1: unwind: Reorganise the stacktrace support

2009-02-12T13:21:17Z

This patch changes the walk_stacktrace and its callers for easier integration of stack unwinding. The arch/arm/kernel/stacktrace.h file is also moved to arch/arm/include/asm/stacktrace.h. Signed-off-by: Catalin Marinas Signed-off-by: Russell King

Merge branch 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2008-07-15T17:31:35Z

* 'core/stacktrace' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: generic-ipi: powerpc/generic-ipi tree build failure stacktrace: fix build failure on sparc64 stacktrace: export save_stack_trace[_tsk] stacktrace: fix modular build, export print_stack_trace and save_stack_trace backtrace: replace timer with tasklet + completions stacktrace: add saved stack traces to backtrace self-test stacktrace: print_stack_trace() cleanup debugging: make stacktrace independent from DEBUG_KERNEL stacktrace: don't crash on invalid stack trace structs