| Message ID | 4DD218B1.7080601@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 17, 2011 at 02:41:53PM +0800, Huang Ying wrote: > On 05/17/2011 03:33 AM, Don Zickus wrote: > > On Tue, May 10, 2011 at 11:08:41AM +0800, Huang Ying wrote: > >> The testing of Generic Hardware Error Source (GHES) is quite > >> difficult, because special hardware is needed to trigger the hardware > >> error. So a software based hardware error injector for GHES is > >> implemented. > >> > >> Error notification is not provided in this patch. So you still need > >> some NMI/SCI/IRQ injecting support to make it work. > > > > Should we add that to this patch, otherwise it seems like the injection > > isn't very useful or intuitive from the end-user perspective that they > > have to provide their own notification source (ie NMI/SCI/MCE/IRQ). > > We can provide the NMI/SCI/IRQ injecting in another patch. What do you > think about the NMI injecting patch attached? I understand what the patch is doing and I like the various injection points, but looking at your other injection modules I start to wonder if there is a smarter and easier way to do all this. I believe the software injection is definitely useful but it does add bloat to the kernel. I am starting to like Ingo's event filtering idea for stuff like this I think (though I am still wrapping my head around it). The beauty of kprobes and tracepoints and even jump labels was that they were not very intrusive, they did their work on the side. It would be nice if we could figure out a framework for the injection stuff that did something similar. Perhaps Ingo has some ideas? Cheers, Don > > BTW: MCE will not be processed by GHES. > > Best Regards, > Huang Ying > Subject: [RFC] x86, NMI, NMI injecting support > > This patch implements trigger NMI on specified CPUs. At the same time, > the NMI reason (contents of port 0x61) can be faked too. This can be > used to debug and test the NMI handler. > > Signed-off-by: Huang Ying <ying.huang@intel.com> > --- > arch/x86/Kconfig.debug | 10 +++ > arch/x86/include/asm/mach_traps.h | 9 ++ > arch/x86/kernel/Makefile | 1 > arch/x86/kernel/nmi_inject.c | 117 ++++++++++++++++++++++++++++++++++++++ > arch/x86/kernel/traps.c | 34 ++++++++++- > 5 files changed, 167 insertions(+), 4 deletions(-) > > --- a/arch/x86/Kconfig.debug > +++ b/arch/x86/Kconfig.debug > @@ -304,4 +304,14 @@ config DEBUG_STRICT_USER_COPY_CHECKS > > If unsure, or if you run an older (pre 4.4) gcc, say N. > > +config NMI_INJECT > + tristate "NMI injecting support" > + depends on DEBUG_KERNEL > + ---help--- > + This can be used to trigger NMI on specified CPUs. And the > + reason of NMI (contents of port 0x61) can be faked > + too. This can be used to debug and test the NMI handler. > + > + If unsure, say N. > + > endmenu > --- a/arch/x86/include/asm/mach_traps.h > +++ b/arch/x86/include/asm/mach_traps.h > @@ -17,7 +17,7 @@ > #define NMI_REASON_CLEAR_IOCHK 0x08 > #define NMI_REASON_CLEAR_MASK 0x0f > > -static inline unsigned char get_nmi_reason(void) > +static inline unsigned char __get_nmi_reason(void) > { > return inb(NMI_REASON_PORT); > } > @@ -40,4 +40,11 @@ static inline void reassert_nmi(void) > unlock_cmos(); > } > > +struct nmi_reason_inject_data { > + unsigned char reason; > + unsigned char valid : 1; > +}; > + > +extern struct nmi_reason_inject_data nmi_reason_inject_data; > + > #endif /* _ASM_X86_MACH_DEFAULT_MACH_TRAPS_H */ > --- a/arch/x86/kernel/Makefile > +++ b/arch/x86/kernel/Makefile > @@ -113,6 +113,7 @@ obj-$(CONFIG_SWIOTLB) += pci-swiotlb.o > obj-$(CONFIG_OF) += devicetree.o > > obj-y += hwerr.o > +obj-$(CONFIG_NMI_INJECT) += nmi_inject.o > > ### > # 64 bit specific files > --- /dev/null > +++ b/arch/x86/kernel/nmi_inject.c > @@ -0,0 +1,117 @@ > +/* > + * NMI injector, for NMI handler testing > + * > + * Copyright 2010 Intel Corp. > + * Author: Huang Ying <ying.huang@intel.com> > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License version > + * 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA > + */ > + > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/debugfs.h> > +#include <linux/cpu.h> > +#include <asm/mach_traps.h> > +#include <asm/apic.h> > + > +static int nmi_reason_inject_get(void *data, u64 *val) > +{ > + if (nmi_reason_inject_data.valid) > + *val = nmi_reason_inject_data.reason; > + else > + *val = ~0ULL; > + return 0; > +} > + > +static int nmi_reason_inject_set(void *data, u64 val) > +{ > + nmi_reason_inject_data.reason = val; > + nmi_reason_inject_data.valid = 1; > + return 0; > +} > + > +DEFINE_SIMPLE_ATTRIBUTE(nmi_reason_inject_fops, nmi_reason_inject_get, > + nmi_reason_inject_set, "0x%llx\n"); > + > +static int nmi_reason_uninject_set(void *data, u64 val) > +{ > + nmi_reason_inject_data.valid = 0; > + return 0; > +} > + > +DEFINE_SIMPLE_ATTRIBUTE(nmi_reason_uninject_fops, NULL, > + nmi_reason_uninject_set, "%llu\n"); > + > +static int nmi_inject_set(void *data, u64 val) > +{ > + int cpu; > + cpumask_var_t cpu_mask; > + > + alloc_cpumask_var(&cpu_mask, GFP_KERNEL); > + cpumask_clear(cpu_mask); > + for_each_online_cpu(cpu) { > + if (cpu >= sizeof(val)) > + continue; > + if (val & (1ULL << cpu)) > + cpumask_set_cpu(cpu, cpu_mask); > + } > + if (!cpumask_empty(cpu_mask)) > + apic->send_IPI_mask(cpu_mask, NMI_VECTOR); > + free_cpumask_var(cpu_mask); > + return 0; > +} > + > +DEFINE_SIMPLE_ATTRIBUTE(nmi_inject_fops, NULL, nmi_inject_set, "0x%llx\n"); > + > +static struct dentry *nmi_debug_dir; > + > +static int __init nmi_inject_init(void) > +{ > + int rc; > + struct dentry *de; > + > + rc = -ENOMEM; > + nmi_debug_dir = debugfs_create_dir("nmi", NULL); > + if (!nmi_debug_dir) > + return rc; > + de = debugfs_create_file("inject", S_IWUSR, nmi_debug_dir, > + NULL, &nmi_inject_fops); > + if (!de) > + goto err; > + de = debugfs_create_file("reason_inject", S_IRUSR | S_IWUSR, > + nmi_debug_dir, NULL, &nmi_reason_inject_fops); > + if (!de) > + goto err; > + de = debugfs_create_file("reason_uninject", S_IWUSR, > + nmi_debug_dir, NULL, &nmi_reason_uninject_fops); > + if (!de) > + goto err; > + > + return 0; > +err: > + debugfs_remove_recursive(nmi_debug_dir); > + return rc; > +} > + > +static void __exit nmi_inject_exit(void) > +{ > + debugfs_remove_recursive(nmi_debug_dir); > +} > + > +module_init(nmi_inject_init); > +module_exit(nmi_inject_exit); > + > +MODULE_AUTHOR("Huang Ying"); > +MODULE_DESCRIPTION("NMI injecting support"); > +MODULE_LICENSE("GPL"); > --- a/arch/x86/kernel/traps.c > +++ b/arch/x86/kernel/traps.c > @@ -316,6 +316,34 @@ static int __init setup_unknown_nmi_pani > } > __setup("unknown_nmi_panic", setup_unknown_nmi_panic); > > +struct nmi_reason_inject_data nmi_reason_inject_data; > +EXPORT_SYMBOL_GPL(nmi_reason_inject_data); > + > +static inline unsigned char get_nmi_reason(void) > +{ > + if (nmi_reason_inject_data.valid) > + return nmi_reason_inject_data.reason; > + else > + return __get_nmi_reason(); > +} > + > +static inline void outb_nmi_reason(unsigned char reason) > +{ > + static unsigned char prev_reason; > + > + if (nmi_reason_inject_data.valid) { > + if (reason & NMI_REASON_CLEAR_SERR) > + nmi_reason_inject_data.reason &= ~NMI_REASON_SERR; > + if (prev_reason == (reason | NMI_REASON_CLEAR_IOCHK) && > + !(reason & NMI_REASON_CLEAR_IOCHK)) > + nmi_reason_inject_data.reason &= ~NMI_REASON_IOCHK; > + if (!nmi_reason_inject_data.reason) > + nmi_reason_inject_data.valid = 0; > + prev_reason = reason; > + } else > + outb(reason, NMI_REASON_PORT); > +} > + > static notrace __kprobes void > pci_serr_error(unsigned char reason, struct pt_regs *regs) > { > @@ -340,7 +368,7 @@ pci_serr_error(unsigned char reason, str > > /* Clear and disable the PCI SERR error line. */ > reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_SERR; > - outb(reason, NMI_REASON_PORT); > + outb_nmi_reason(reason); > } > > static notrace __kprobes void > @@ -358,7 +386,7 @@ io_check_error(unsigned char reason, str > > /* Re-enable the IOCK line, wait for a few seconds */ > reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_IOCHK; > - outb(reason, NMI_REASON_PORT); > + outb_nmi_reason(reason); > > i = 20000; > while (--i) { > @@ -367,7 +395,7 @@ io_check_error(unsigned char reason, str > } > > reason &= ~NMI_REASON_CLEAR_IOCHK; > - outb(reason, NMI_REASON_PORT); > + outb_nmi_reason(reason); > } > > void set_unknown_nmi_as_hwerr(void) -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
* Don Zickus <dzickus@redhat.com> wrote: > On Tue, May 17, 2011 at 02:41:53PM +0800, Huang Ying wrote: > > On 05/17/2011 03:33 AM, Don Zickus wrote: > > > On Tue, May 10, 2011 at 11:08:41AM +0800, Huang Ying wrote: > > >> The testing of Generic Hardware Error Source (GHES) is quite > > >> difficult, because special hardware is needed to trigger the hardware > > >> error. So a software based hardware error injector for GHES is > > >> implemented. > > >> > > >> Error notification is not provided in this patch. So you still need > > >> some NMI/SCI/IRQ injecting support to make it work. > > > > > > Should we add that to this patch, otherwise it seems like the injection > > > isn't very useful or intuitive from the end-user perspective that they > > > have to provide their own notification source (ie NMI/SCI/MCE/IRQ). > > > > We can provide the NMI/SCI/IRQ injecting in another patch. What do you > > think about the NMI injecting patch attached? > > I understand what the patch is doing and I like the various injection > points, but looking at your other injection modules I start to wonder if > there is a smarter and easier way to do all this. I believe the software > injection is definitely useful but it does add bloat to the kernel. > > I am starting to like Ingo's event filtering idea for stuff like this I > think (though I am still wrapping my head around it). The beauty of > kprobes and tracepoints and even jump labels was that they were not very > intrusive, they did their work on the side. It would be nice if we could > figure out a framework for the injection stuff that did something similar. > > Perhaps Ingo has some ideas? Boris has injection in the EDAC code as well and wants it for RAS purposes and i recently outlined to him how event injection could possible look like in the not so far future: ----------------> I think the model we want is to inject actual perf events at the *kernel* level, and to add the ability for some events (MCE events here) to also run a (optional) callback once user-space does that injection. So for example [sufficienty privileged] user-space could inject *any* perf event - for example a PERF_COUNT_HW_CACHE_MISSES event (for test purposes) and any tooling that runs could not tell apart this injected event from a real event. Once we have that, adding a injection callback to MCE events is just another step: such a callback could propagate the injected event to the real hardware for example, if that is possible. (it would validate, etc. as well) In the generic case the event just gets injected into the perf event stream. The ABI for injection could be some obvious extension, either another ioctl variant to the perf fd itself, we already have various ways to access it: #define PERF_EVENT_IOC_ENABLE _IO ('$', 0) #define PERF_EVENT_IOC_DISABLE _IO ('$', 1) #define PERF_EVENT_IOC_REFRESH _IO ('$', 2) #define PERF_EVENT_IOC_RESET _IO ('$', 3) #define PERF_EVENT_IOC_PERIOD _IOW('$', 4, __u64) #define PERF_EVENT_IOC_SET_OUTPUT _IO ('$', 5) #define PERF_EVENT_IOC_SET_FILTER _IOW('$', 6, char *) Or sys_write() access to the perf event fd. The sys_write() one looks like the conceptually nicest solution to me, because we can read() the fd as well to get event (counts..) out of it. I think this model would give us a *lot* of testing power, and we could utilize arbitrary hardware-injection capabilities as well. <---------------- That way what would remain in mm/memory-failure.c file is all the useful (and interesting!) MM specific knowledge: the method of getting to a list of affected tasks for policy action, to collect the tasks that are affected by an anonymous page going bad, or by a pagecache page going bad, etc. These would be offered as filter action functionality, and could be triggered from filters straight in the kernel, without having to touch a user-space daemon. The whole boring transport, filtering, enumeration and configuration that is duplicated here would go away and would be replaced by EVENT() definitions in the places that generate events and callbacks to filter action in mm/memory-inject.c. Now what is somewhat unfortunate as a practical matter is that some of this functionality has already been exposed in semi-ABI ways in an ad-hoc fashion, so some of the design may be hardcoded. That does not keep me from pointing out when i see the mess growing ... :-) Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, May 17, 2011 at 09:18:03PM +0200, Ingo Molnar wrote: > So for example [sufficienty privileged] user-space could inject *any* > perf event - for example a PERF_COUNT_HW_CACHE_MISSES event (for test > purposes) and any tooling that runs could not tell apart this injected > event from a real event. Yeah about that, I was recently speculating how that would work. So do we do $ perf record ... in the one xterm, and, in the other, $ perf inject so that while recording, we can inject some events from userspace? Or do we inject it, it gets buffered somewhere in the meantime and then the next perf record session sees it along with the remaining injection events? The ras inject part would obviously only use the callback and the injection will happen immediately. Hmm...
* Borislav Petkov <bp@alien8.de> wrote: > On Tue, May 17, 2011 at 09:18:03PM +0200, Ingo Molnar wrote: > > So for example [sufficienty privileged] user-space could inject *any* > > perf event - for example a PERF_COUNT_HW_CACHE_MISSES event (for test > > purposes) and any tooling that runs could not tell apart this injected > > event from a real event. > > Yeah about that, I was recently speculating how that would work. So do we do > > $ perf record ... > > in the one xterm, and, in the other, > > $ perf inject > > so that while recording, we can inject some events from userspace? Or > do we inject it, it gets buffered somewhere in the meantime and then > the next perf record session sees it along with the remaining injection > events? Well, for persistent events there would be interim buffering even if there's no observation going on anywhere. I.e. there's always an 'observer' of events. For non-persistent events, if they are injected, then they are like trace events for which nobody is interested in: they are lost. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Subject: [RFC] x86, NMI, NMI injecting support This patch implements trigger NMI on specified CPUs. At the same time, the NMI reason (contents of port 0x61) can be faked too. This can be used to debug and test the NMI handler. Signed-off-by: Huang Ying <ying.huang@intel.com> --- arch/x86/Kconfig.debug | 10 +++ arch/x86/include/asm/mach_traps.h | 9 ++ arch/x86/kernel/Makefile | 1 arch/x86/kernel/nmi_inject.c | 117 ++++++++++++++++++++++++++++++++++++++ arch/x86/kernel/traps.c | 34 ++++++++++- 5 files changed, 167 insertions(+), 4 deletions(-) --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -304,4 +304,14 @@ config DEBUG_STRICT_USER_COPY_CHECKS If unsure, or if you run an older (pre 4.4) gcc, say N. +config NMI_INJECT + tristate "NMI injecting support" + depends on DEBUG_KERNEL + ---help--- + This can be used to trigger NMI on specified CPUs. And the + reason of NMI (contents of port 0x61) can be faked + too. This can be used to debug and test the NMI handler. + + If unsure, say N. + endmenu --- a/arch/x86/include/asm/mach_traps.h +++ b/arch/x86/include/asm/mach_traps.h @@ -17,7 +17,7 @@ #define NMI_REASON_CLEAR_IOCHK 0x08 #define NMI_REASON_CLEAR_MASK 0x0f -static inline unsigned char get_nmi_reason(void) +static inline unsigned char __get_nmi_reason(void) { return inb(NMI_REASON_PORT); } @@ -40,4 +40,11 @@ static inline void reassert_nmi(void) unlock_cmos(); } +struct nmi_reason_inject_data { + unsigned char reason; + unsigned char valid : 1; +}; + +extern struct nmi_reason_inject_data nmi_reason_inject_data; + #endif /* _ASM_X86_MACH_DEFAULT_MACH_TRAPS_H */ --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -113,6 +113,7 @@ obj-$(CONFIG_SWIOTLB) += pci-swiotlb.o obj-$(CONFIG_OF) += devicetree.o obj-y += hwerr.o +obj-$(CONFIG_NMI_INJECT) += nmi_inject.o ### # 64 bit specific files --- /dev/null +++ b/arch/x86/kernel/nmi_inject.c @@ -0,0 +1,117 @@ +/* + * NMI injector, for NMI handler testing + * + * Copyright 2010 Intel Corp. + * Author: Huang Ying <ying.huang@intel.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/debugfs.h> +#include <linux/cpu.h> +#include <asm/mach_traps.h> +#include <asm/apic.h> + +static int nmi_reason_inject_get(void *data, u64 *val) +{ + if (nmi_reason_inject_data.valid) + *val = nmi_reason_inject_data.reason; + else + *val = ~0ULL; + return 0; +} + +static int nmi_reason_inject_set(void *data, u64 val) +{ + nmi_reason_inject_data.reason = val; + nmi_reason_inject_data.valid = 1; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(nmi_reason_inject_fops, nmi_reason_inject_get, + nmi_reason_inject_set, "0x%llx\n"); + +static int nmi_reason_uninject_set(void *data, u64 val) +{ + nmi_reason_inject_data.valid = 0; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(nmi_reason_uninject_fops, NULL, + nmi_reason_uninject_set, "%llu\n"); + +static int nmi_inject_set(void *data, u64 val) +{ + int cpu; + cpumask_var_t cpu_mask; + + alloc_cpumask_var(&cpu_mask, GFP_KERNEL); + cpumask_clear(cpu_mask); + for_each_online_cpu(cpu) { + if (cpu >= sizeof(val)) + continue; + if (val & (1ULL << cpu)) + cpumask_set_cpu(cpu, cpu_mask); + } + if (!cpumask_empty(cpu_mask)) + apic->send_IPI_mask(cpu_mask, NMI_VECTOR); + free_cpumask_var(cpu_mask); + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(nmi_inject_fops, NULL, nmi_inject_set, "0x%llx\n"); + +static struct dentry *nmi_debug_dir; + +static int __init nmi_inject_init(void) +{ + int rc; + struct dentry *de; + + rc = -ENOMEM; + nmi_debug_dir = debugfs_create_dir("nmi", NULL); + if (!nmi_debug_dir) + return rc; + de = debugfs_create_file("inject", S_IWUSR, nmi_debug_dir, + NULL, &nmi_inject_fops); + if (!de) + goto err; + de = debugfs_create_file("reason_inject", S_IRUSR | S_IWUSR, + nmi_debug_dir, NULL, &nmi_reason_inject_fops); + if (!de) + goto err; + de = debugfs_create_file("reason_uninject", S_IWUSR, + nmi_debug_dir, NULL, &nmi_reason_uninject_fops); + if (!de) + goto err; + + return 0; +err: + debugfs_remove_recursive(nmi_debug_dir); + return rc; +} + +static void __exit nmi_inject_exit(void) +{ + debugfs_remove_recursive(nmi_debug_dir); +} + +module_init(nmi_inject_init); +module_exit(nmi_inject_exit); + +MODULE_AUTHOR("Huang Ying"); +MODULE_DESCRIPTION("NMI injecting support"); +MODULE_LICENSE("GPL"); --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -316,6 +316,34 @@ static int __init setup_unknown_nmi_pani } __setup("unknown_nmi_panic", setup_unknown_nmi_panic); +struct nmi_reason_inject_data nmi_reason_inject_data; +EXPORT_SYMBOL_GPL(nmi_reason_inject_data); + +static inline unsigned char get_nmi_reason(void) +{ + if (nmi_reason_inject_data.valid) + return nmi_reason_inject_data.reason; + else + return __get_nmi_reason(); +} + +static inline void outb_nmi_reason(unsigned char reason) +{ + static unsigned char prev_reason; + + if (nmi_reason_inject_data.valid) { + if (reason & NMI_REASON_CLEAR_SERR) + nmi_reason_inject_data.reason &= ~NMI_REASON_SERR; + if (prev_reason == (reason | NMI_REASON_CLEAR_IOCHK) && + !(reason & NMI_REASON_CLEAR_IOCHK)) + nmi_reason_inject_data.reason &= ~NMI_REASON_IOCHK; + if (!nmi_reason_inject_data.reason) + nmi_reason_inject_data.valid = 0; + prev_reason = reason; + } else + outb(reason, NMI_REASON_PORT); +} + static notrace __kprobes void pci_serr_error(unsigned char reason, struct pt_regs *regs) { @@ -340,7 +368,7 @@ pci_serr_error(unsigned char reason, str /* Clear and disable the PCI SERR error line. */ reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_SERR; - outb(reason, NMI_REASON_PORT); + outb_nmi_reason(reason); } static notrace __kprobes void @@ -358,7 +386,7 @@ io_check_error(unsigned char reason, str /* Re-enable the IOCK line, wait for a few seconds */ reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_IOCHK; - outb(reason, NMI_REASON_PORT); + outb_nmi_reason(reason); i = 20000; while (--i) { @@ -367,7 +395,7 @@ io_check_error(unsigned char reason, str } reason &= ~NMI_REASON_CLEAR_IOCHK; - outb(reason, NMI_REASON_PORT); + outb_nmi_reason(reason); } void set_unknown_nmi_as_hwerr(void)