arch/tile: support signal "exception-trace" hook
This change adds support for /proc/sys/debug/exception-trace to tile.
Like x86 and sparc, by default it is set to "1", generating a one-line
printk whenever a user process crashes. By setting it to "2", we get
a much more complete userspace diagnostic at crash time, including
a user-space backtrace, register dump, and memory dump around the
address of the crash.
Some vestiges of the Tilera-internal version of this support are
removed with this patch (the show_crashinfo variable and the
arch_coredump_signal function). We retain a "crashinfo" boot parameter
which allows you to set the boot-time value of exception-trace.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/kernel/single_step.c b/arch/tile/kernel/single_step.c
index 86df5a2..4032ca8 100644
--- a/arch/tile/kernel/single_step.c
+++ b/arch/tile/kernel/single_step.c
@@ -186,6 +186,8 @@
.si_code = SEGV_MAPERR,
.si_addr = addr
};
+ trace_unhandled_signal("segfault", regs,
+ (unsigned long)addr, SIGSEGV);
force_sig_info(info.si_signo, &info, current);
return (tile_bundle_bits) 0;
}
@@ -196,6 +198,8 @@
.si_code = BUS_ADRALN,
.si_addr = addr
};
+ trace_unhandled_signal("unaligned trap", regs,
+ (unsigned long)addr, SIGBUS);
force_sig_info(info.si_signo, &info, current);
return (tile_bundle_bits) 0;
}