Re: [PATCH 6/7] powerpc/traps: Print signal name for unhandled signals

LEROY Christophe
2018-07-25T15:49:33Z

Murilo Opsfelder Araujo <muriloo@linux.ibm.com> a écrit :

> This adds a human-readable name in the unhandled signal message.
>
> Before this patch, a page fault looked like:
>
> Jul 11 16:04:11 localhost kernel: pandafault[6303]: unhandled
> signal 11 at 00000000100007d0 nip 000000001000061c lr
> 00007fff93c55100 code 2 in pandafault[10000000+10000]
>
> After this patch, a page fault looks like:
>
> Jul 11 18:14:48 localhost kernel: pandafault[6352]: segfault
> (11) at 000000013a2a09f8 nip 000000013a2a086c lr 00007fffb63e5100
> code 2 in pandafault[13a2a0000+10000]
>
> Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
> ---
> arch/powerpc/kernel/traps.c | 43 +++++++++++++++++++++++++++++++++----
> 1 file changed, 39 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
> index e6c43ef9fb50..e55ee639d010 100644
> --- a/arch/powerpc/kernel/traps.c
> +++ b/arch/powerpc/kernel/traps.c
> @@ -96,6 +96,41 @@ EXPORT_SYMBOL(__debugger_fault_handler);
> #define TM_DEBUG(x...) do { } while(0)
> #endif
>
> +static const char *signames[SIGRTMIN + 1] = {
> + "UNKNOWN",
> + "SIGHUP", // 1
> + "SIGINT", // 2
> + "SIGQUIT", // 3
> + "SIGILL", // 4
> + "unhandled trap", // 5 = SIGTRAP
> + "SIGABRT", // 6 = SIGIOT
> + "bus error", // 7 = SIGBUS
> + "floating point exception", // 8 = SIGFPE
> + "illegal instruction", // 9 = SIGILL
> + "SIGUSR1", // 10
> + "segfault", // 11 = SIGSEGV
> + "SIGUSR2", // 12
> + "SIGPIPE", // 13
> + "SIGALRM", // 14
> + "SIGTERM", // 15
> + "SIGSTKFLT", // 16
> + "SIGCHLD", // 17
> + "SIGCONT", // 18
> + "SIGSTOP", // 19
> + "SIGTSTP", // 20
> + "SIGTTIN", // 21
> + "SIGTTOU", // 22
> + "SIGURG", // 23
> + "SIGXCPU", // 24
> + "SIGXFSZ", // 25
> + "SIGVTALRM", // 26
> + "SIGPROF", // 27
> + "SIGWINCH", // 28
> + "SIGIO", // 29 = SIGPOLL = SIGLOST
> + "SIGPWR", // 30
> + "SIGSYS", // 31 = SIGUNUSED
> +};
> +
> /*
> * Trap & Exception support
> */
> @@ -314,10 +349,10 @@ static void show_signal_msg(int signr, struct
> pt_regs *regs, int code,
> if (!unhandled_signal(current, signr))
> return;
>
> - pr_info("%s[%d]: unhandled signal %d at "REG_FMT \
> - " nip "REG_FMT" lr "REG_FMT" code %x",
> - current->comm, current->pid, signr, addr,
> - regs->nip, regs->link, code);
> + pr_info("%s[%d]: %s (%d) at "REG_FMT" nip "REG_FMT \
> + " lr "REG_FMT" code %x",
> + current->comm, current->pid, signames[signr],
> + signr, addr, regs->nip, regs->link, code);

Are we sure that signr is always within the limits of the table ?

Christophe
>
> print_vma_addr(KERN_CONT " in ", regs->nip);
>
> --
> 2.17.1