Commit-ID: bda62633983f9db49ce0b1a9235b3709c1cda5f0 Gitweb: http://git.kernel.org/tip/bda62633983f9db49ce0b1a9235b3709c1cda5f0 Author: Don Zickus <dzickus@xxxxxxxxxx> AuthorDate: Thu, 13 Oct 2011 15:14:27 -0400 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Mon, 5 Dec 2011 12:00:23 +0100 x86, NMI: Add knob to disable using NMI IPIs to stop cpus Some machines may exhibit problems using the NMI to stop other cpus. This knob just allows one to revert back to the original behaviour to help diagnose the problem. V2: make function static Signed-off-by: Don Zickus <dzickus@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Robert Richter <robert.richter@xxxxxxx> Cc: seiji.aguchi@xxxxxxx Cc: vgoyal@xxxxxxxxxx Cc: mjg@xxxxxxxxxx Cc: tony.luck@xxxxxxxxx Cc: gong.chen@xxxxxxxxx Cc: satoru.moriya@xxxxxxx Cc: avi@xxxxxxxxxx Cc: Andi Kleen <andi@xxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1318533267-18880-4-git-send-email-dzickus@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- Documentation/kernel-parameters.txt | 4 ++++ arch/x86/kernel/smp.c | 13 +++++++++++++ 2 files changed, 17 insertions(+), 0 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index a0c5c5f..b4339e5 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1796,6 +1796,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nomfgpt [X86-32] Disable Multi-Function General Purpose Timer usage (for AMD Geode machines). + nonmi_ipi [X86] Disable using NMI IPIs during panic/reboot to + shutdown the other cpus. Instead use the REBOOT_VECTOR + irq. + nopat [X86] Disable PAT (page attribute table extension of pagetables) support. diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c index e72b175..113acda 100644 --- a/arch/x86/kernel/smp.c +++ b/arch/x86/kernel/smp.c @@ -249,6 +249,11 @@ static void native_irq_stop_other_cpus(int wait) local_irq_restore(flags); } +static void native_smp_disable_nmi_ipi(void) +{ + smp_ops.stop_other_cpus = native_irq_stop_other_cpus; +} + /* * Reschedule call back. */ @@ -280,6 +285,14 @@ void smp_call_function_single_interrupt(struct pt_regs *regs) irq_exit(); } +static int __init nonmi_ipi_setup(char *str) +{ + native_smp_disable_nmi_ipi(); + return 1; +} + +__setup("nonmi_ipi", nonmi_ipi_setup); + struct smp_ops smp_ops = { .smp_prepare_boot_cpu = native_smp_prepare_boot_cpu, .smp_prepare_cpus = native_smp_prepare_cpus, -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html