@@ -28,6 +28,7 @@ enum kmsg_dump_reason {
KMSG_DUMP_RESTART,
KMSG_DUMP_HALT,
KMSG_DUMP_POWEROFF,
+ KMSG_DUMP_MAX
};
/**
@@ -3157,12 +3157,19 @@ void kmsg_dump(enum kmsg_dump_reason reason)
struct kmsg_dumper *dumper;
unsigned long flags;
- if ((reason > KMSG_DUMP_OOPS) && !always_kmsg_dump)
- return;
-
rcu_read_lock();
list_for_each_entry_rcu(dumper, &dump_list, list) {
- if (dumper->max_reason && reason > dumper->max_reason)
+ enum kmsg_dump_reason cur_reason = dumper->max_reason;
+
+ /*
+ * If client has not provided a specific max_reason, default
+ * to KMSG_DUMP_OOPS, unless always_kmsg_dump was set.
+ */
+ if (cur_reason == KMSG_DUMP_UNDEF) {
+ cur_reason = always_kmsg_dump ? KMSG_DUMP_MAX :
+ KMSG_DUMP_OOPS;
+ }
+ if (reason > cur_reason)
continue;
/* initialize iterator with data about the stored records */
kmsg_dump() allows to dump kmesg buffer for various system events: oops, panic, reboot, etc. It provides an interface to register a callback call for clients, and in that callback interface there is a field "max_reason" which gets ignored unless always_kmsg_dump is passed as kernel parameter. Allow clients to decide max_reason, and keep the current behavior when max_reason is not set. Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> --- include/linux/kmsg_dump.h | 1 + kernel/printk/printk.c | 15 +++++++++++---- 2 files changed, 12 insertions(+), 4 deletions(-)