[PATCH 27/37] debug_core,kdb: Allow the debug core to process a recursive debug entry

From: Jason Wessel
Date: Wed Dec 23 2009 - 16:22:52 EST


This allows kdb to debug a crash with in the kms code with a
single level recursive re-entry.

Signed-off-by: Jason Wessel <jason.wessel@xxxxxxxxxxxxx>
---
kernel/debug/debug_core.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index e44e693..e6c6f8a 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -443,6 +443,10 @@ static int kgdb_reenter_check(struct kgdb_state *ks)
}

printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n");
+#ifdef CONFIG_KGDB_KDB
+ /* Allow kdb to debug itself one level */
+ return 0;
+#endif
dump_stack();
panic("Recursive entry to debugger");

@@ -487,6 +491,9 @@ acquirelock:
smp_wmb();
atomic_set(&cpu_in_kgdb[cpu], 1);

+ if (exception_level == 1)
+ goto cpu_master_loop;
+
/*
* CPU will loop if it is a slave or request to become a kgdb
* master cpu and acquire the kgdb_active lock:
--
1.6.4.rc1

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