[PATCH] arm:traps: Don't print stack or raw PC/LR values in backtraces

Sebastian Andrzej Siewior bigeasy at linutronix.de
Mon Oct 12 06:03:18 EDT 2020


On 2020-10-11 22:32:38 [+0100], Russell King - ARM Linux admin wrote:
> I don't have a problem getting rid of the hex numbers in [< >]
> although then I will need to convert the symbol back to an address
> using the vmlinux to then calculate its address to then find the
> appropriate place in the objdump output - because objdump does
> _not_ use the symbol+offset annotation.  Yes, I really do look up
> the numeric addresses in the objdump output to then read the
> disassembly.
> 
> $ objdump -d vmlinux | less
> 
> and then search for the address is the fastest and most convenient
> way for me rather than having to deal with some random script.
> 
> Maybe I'm just antequated about how I do my debugging, but this
> seems to me to be the most efficient and fastest way.

besides what Josh mentioned, there is also 
         scripts/decode_stacktrace.sh path-vmlinux
 
where you can copy/paste your complete stack trace / dmesg and it will
decode it line by line. So if you invoke
        scripts/decode_stacktrace.sh vmlinux.o

and paste this:

|[    7.568155] 001: PC is at do_work_pending+0x190/0x5c4
|[    7.568641] 001: LR is at slow_work_pending+0xc/0x20
|[    7.569232] 001: Backtrace:
|[    7.569367] 001: [<c020c2d0>] (do_work_pending) from [<c02000cc>] (slow_work_pending+0xc/0x20)

you get this in return:
|[    7.568155] 001: PC is at do_work_pending (arch/arm/kernel/signal.c:616 arch/arm/kernel/signal.c:670)
|[    7.568641] 001: LR is at slow_work_pending (arch/arm/kernel/entry-common.S:112)
|[    7.569232] 001: Backtrace:
|[    7.569367] 001: (do_work_pending) from slow_work_pending (arch/arm/kernel/entry-common.S:112)

Sebastian



More information about the linux-arm-kernel mailing list