From 8daaa5f8261bffd2f6217a960f9182d0503a5c44 Mon Sep 17 00:00:00 2001 From: Mike Travis Date: Wed, 2 Oct 2013 10:14:18 -0500 Subject: kdb: Add support for external NMI handler to call KGDB/KDB This patch adds a kgdb_nmicallin() interface that can be used by external NMI handlers to call the KGDB/KDB handler. The primary need for this is for those types of NMI interrupts where all the CPUs have already received the NMI signal. Therefore no send_IPI(NMI) is required, and in fact it will cause a 2nd unhandled NMI to occur. This generates the "Dazed and Confuzed" messages. Since all the CPUs are getting the NMI at roughly the same time, it's not guaranteed that the first CPU that hits the NMI handler will manage to enter KGDB and set the dbg_master_lock before the slaves start entering. The new argument "send_ready" was added for KGDB to signal the NMI handler to release the slave CPUs for entry into KGDB. Signed-off-by: Mike Travis Acked-by: Jason Wessel Reviewed-by: Dimitri Sivanich Reviewed-by: Hedi Berriche Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Link: http://lkml.kernel.org/r/20131002151417.928886849@asylum.americas.sgi.com Signed-off-by: Ingo Molnar --- kernel/debug/kdb/kdb_main.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/debug/kdb/kdb_main.c') diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 00eb8f7fbf41..0b097c8a1e50 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -1200,6 +1200,9 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs, instruction_pointer(regs)); kdb_dumpregs(regs); break; + case KDB_REASON_SYSTEM_NMI: + kdb_printf("due to System NonMaskable Interrupt\n"); + break; case KDB_REASON_NMI: kdb_printf("due to NonMaskable Interrupt @ " kdb_machreg_fmt "\n", -- cgit v1.2.3