From 5edd19af18a36a4e22c570b1b969179e0ca1fe4c Mon Sep 17 00:00:00 2001 From: Cliff Wickman Date: Tue, 20 Jul 2010 18:09:05 -0500 Subject: x86, UV: Make kdump avoid stack dumps UV NMI callback's should not write stack dumps when a kdump is to be written. When invoking the crash kernel to write a dump, kdump_nmi_shootdown_cpus() uses NMI's to get all the cpu's to save their register context and halt. But the NMI interrupt handler runs a callback list. This patch sets a flag to prevent any of those callbacks from interfering with the halt of the cpu. For UV, which currently has the only callback to which this is relevant, the uv_handle_nmi() callback should not do dumping of stacks. The 'in_crash_kexec' flag is defined as an extern in kdebug.h firstly because x2apic_uv_x.c includes it. Secondly because some future callback might need the flag to know that it should not enter the debugger. (Such a scenario was in fact present in the 2.6.32 kernel, SuSE distribution, where a call to kdb needed to be avoided.) Signed-off-by: Cliff Wickman LKML-Reference: Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/kdebug.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/include/asm/kdebug.h') diff --git a/arch/x86/include/asm/kdebug.h b/arch/x86/include/asm/kdebug.h index fa7c0b974761..7a2910b3512b 100644 --- a/arch/x86/include/asm/kdebug.h +++ b/arch/x86/include/asm/kdebug.h @@ -33,5 +33,6 @@ extern void __show_regs(struct pt_regs *regs, int all); extern void show_regs(struct pt_regs *regs); extern unsigned long oops_begin(void); extern void oops_end(unsigned long, struct pt_regs *, int signr); +extern int in_crash_kexec; #endif /* _ASM_X86_KDEBUG_H */ -- cgit v1.2.1