Add printout of last accessed sysfs file, added to x86 in
ae87221d3c (sysfs: crash debugging)
Also add the notify_die hook that allows us to print out the ftrace
buffer on oops. This is useful in conjunction with ftrace function_graph:
Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=128 NUMA pSeries
last sysfs file: /sys/class/net/tunl0/type
Dumping ftrace buffer:
...
0) | .sysrq_handle_crash() {
0) 0.476 us | .hash_page();
0) 0.488 us | .xmon_fault_handler();
0) | .bad_page_fault() {
0) | .search_exception_tables() {
0) 0.590 us | .search_module_extables();
0) 2.546 us | }
0) | .printk() {
0) | .vprintk() {
0) 0.488 us | ._raw_spin_lock();
0) 0.572 us | .emit_log_char();
Showing the function graph of a sysrq-c crash.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
66fcb1059d