kern, arm: Dump dmesg on kernel panic/oops

Add helper functions to dump the guest kernel's dmesg buffer to a text
file in m5out. This functionality is split into two parts. First, a
dmesg dump function that can be used in other places:

void Linux::dumpDmesg(ThreadContext *, std::ostream &)

This function is used to implement two PCEvents: DmesgDumpEvent and
KernelPanic event. The only difference between the two is that the
latter produces a gem5 panic instead of a warning in addition to
dumping the kernel log.

Change-Id: I6d2af1d666ace57124089648ea906f6c787ac63c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Gabor Dozsa <gabor.dozsa@arm.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/src/arch/arm/linux/system.hh b/src/arch/arm/linux/system.hh
index ce1d84b6b..709776ffc 100644
--- a/src/arch/arm/linux/system.hh
+++ b/src/arch/arm/linux/system.hh
@@ -95,6 +95,12 @@ class LinuxArmSystem : public GenericArmSystem
      * @param tc thread context that is currentyl executing  */
     void mapPid(ThreadContext* tc, uint32_t pid);
 
+  public: // Exported Python methods
+    /**
+     * Dump the kernel's dmesg buffer to stdout
+     */
+    void dumpDmesg();
+
   private:
     /** Event to halt the simulator if the kernel calls panic()  */
     PCEvent *kernelPanicEvent;