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

Murilo Opsfelder Araujo
2018-07-24T19:28:31Z

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);

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

--
2.17.1