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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-21 19:25:14 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-21 19:25:14 -0700 |
commit | 5ec29e3149d800e6db83c1b6ff441daf319cbbe2 (patch) | |
tree | b23ecaff7078590215e91b2b6aa4c90c2d923e10 /arch | |
parent | abd209b7083b2f3a2a19e522f688e7569f284e5d (diff) | |
parent | 6ff968cca1dfebd4b6fcade87c11658dbfc96932 (diff) | |
download | linux-5ec29e3149d800e6db83c1b6ff441daf319cbbe2.tar.bz2 |
Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core locking updates from Ingo Molnar:
"This update:
- extends and simplifies x86 NMI callback handling code to enhance
and fix the HP hw-watchdog driver
- simplifies the x86 NMI callback handling code to fix a kmemcheck
bug.
- enhances the hung-task debugger"
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/nmi: Fix the type of the nmiaction.flags field
x86/nmi: Fix page faults by nmiaction if kmemcheck is enabled
x86/nmi: Add new NMI queues to deal with IO_CHK and SERR
watchdog, hpwdt: Remove priority option for NMI callback
hung task debugging: Inject NMI when hung and going to panic
Diffstat (limited to 'arch')
-rw-r--r-- | arch/x86/include/asm/nmi.h | 22 | ||||
-rw-r--r-- | arch/x86/kernel/nmi.c | 83 |
2 files changed, 44 insertions, 61 deletions
diff --git a/arch/x86/include/asm/nmi.h b/arch/x86/include/asm/nmi.h index fd3f9f18cf3f..0e3793b821ef 100644 --- a/arch/x86/include/asm/nmi.h +++ b/arch/x86/include/asm/nmi.h @@ -27,6 +27,8 @@ void arch_trigger_all_cpu_backtrace(void); enum { NMI_LOCAL=0, NMI_UNKNOWN, + NMI_SERR, + NMI_IO_CHECK, NMI_MAX }; @@ -35,8 +37,24 @@ enum { typedef int (*nmi_handler_t)(unsigned int, struct pt_regs *); -int register_nmi_handler(unsigned int, nmi_handler_t, unsigned long, - const char *); +struct nmiaction { + struct list_head list; + nmi_handler_t handler; + unsigned long flags; + const char *name; +}; + +#define register_nmi_handler(t, fn, fg, n) \ +({ \ + static struct nmiaction fn##_na = { \ + .handler = (fn), \ + .name = (n), \ + .flags = (fg), \ + }; \ + __register_nmi_handler((t), &fn##_na); \ +}) + +int __register_nmi_handler(unsigned int, struct nmiaction *); void unregister_nmi_handler(unsigned int, const char *); diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 47acaf319165..585be4bd71a5 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -31,14 +31,6 @@ #include <asm/nmi.h> #include <asm/x86_init.h> -#define NMI_MAX_NAMELEN 16 -struct nmiaction { - struct list_head list; - nmi_handler_t handler; - unsigned int flags; - char *name; -}; - struct nmi_desc { spinlock_t lock; struct list_head head; @@ -54,6 +46,14 @@ static struct nmi_desc nmi_desc[NMI_MAX] = .lock = __SPIN_LOCK_UNLOCKED(&nmi_desc[1].lock), .head = LIST_HEAD_INIT(nmi_desc[1].head), }, + { + .lock = __SPIN_LOCK_UNLOCKED(&nmi_desc[2].lock), + .head = LIST_HEAD_INIT(nmi_desc[2].head), + }, + { + .lock = __SPIN_LOCK_UNLOCKED(&nmi_desc[3].lock), + .head = LIST_HEAD_INIT(nmi_desc[3].head), + }, }; @@ -107,11 +107,14 @@ static int notrace __kprobes nmi_handle(unsigned int type, struct pt_regs *regs, return handled; } -static int __setup_nmi(unsigned int type, struct nmiaction *action) +int __register_nmi_handler(unsigned int type, struct nmiaction *action) { struct nmi_desc *desc = nmi_to_desc(type); unsigned long flags; + if (!action->handler) + return -EINVAL; + spin_lock_irqsave(&desc->lock, flags); /* @@ -120,6 +123,8 @@ static int __setup_nmi(unsigned int type, struct nmiaction *action) * to manage expectations */ WARN_ON_ONCE(type == NMI_UNKNOWN && !list_empty(&desc->head)); + WARN_ON_ONCE(type == NMI_SERR && !list_empty(&desc->head)); + WARN_ON_ONCE(type == NMI_IO_CHECK && !list_empty(&desc->head)); /* * some handlers need to be executed first otherwise a fake @@ -133,8 +138,9 @@ static int __setup_nmi(unsigned int type, struct nmiaction *action) spin_unlock_irqrestore(&desc->lock, flags); return 0; } +EXPORT_SYMBOL(__register_nmi_handler); -static struct nmiaction *__free_nmi(unsigned int type, const char *name) +void unregister_nmi_handler(unsigned int type, const char *name) { struct nmi_desc *desc = nmi_to_desc(type); struct nmiaction *n; @@ -157,61 +163,16 @@ static struct nmiaction *__free_nmi(unsigned int type, const char *name) spin_unlock_irqrestore(&desc->lock, flags); synchronize_rcu(); - return (n); } - -int register_nmi_handler(unsigned int type, nmi_handler_t handler, - unsigned long nmiflags, const char *devname) -{ - struct nmiaction *action; - int retval = -ENOMEM; - - if (!handler) - return -EINVAL; - - action = kzalloc(sizeof(struct nmiaction), GFP_KERNEL); - if (!action) - goto fail_action; - - action->handler = handler; - action->flags = nmiflags; - action->name = kstrndup(devname, NMI_MAX_NAMELEN, GFP_KERNEL); - if (!action->name) - goto fail_action_name; - - retval = __setup_nmi(type, action); - - if (retval) - goto fail_setup_nmi; - - return retval; - -fail_setup_nmi: - kfree(action->name); -fail_action_name: - kfree(action); -fail_action: - - return retval; -} -EXPORT_SYMBOL_GPL(register_nmi_handler); - -void unregister_nmi_handler(unsigned int type, const char *name) -{ - struct nmiaction *a; - - a = __free_nmi(type, name); - if (a) { - kfree(a->name); - kfree(a); - } -} - EXPORT_SYMBOL_GPL(unregister_nmi_handler); static notrace __kprobes void pci_serr_error(unsigned char reason, struct pt_regs *regs) { + /* check to see if anyone registered against these types of errors */ + if (nmi_handle(NMI_SERR, regs, false)) + return; + pr_emerg("NMI: PCI system error (SERR) for reason %02x on CPU %d.\n", reason, smp_processor_id()); @@ -241,6 +202,10 @@ io_check_error(unsigned char reason, struct pt_regs *regs) { unsigned long i; + /* check to see if anyone registered against these types of errors */ + if (nmi_handle(NMI_IO_CHECK, regs, false)) + return; + pr_emerg( "NMI: IOCK error (debug interrupt?) for reason %02x on CPU %d.\n", reason, smp_processor_id()); |