Messages in this thread | | | Subject | Re: [V3][PATCH 2/6] x86, nmi: create new NMI handler routines | From | Peter Zijlstra <> | Date | Fri, 26 Aug 2011 11:44:12 +0200 |
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On Thu, 2011-08-25 at 12:45 -0400, Don Zickus wrote: > +static int __setup_nmi(unsigned int type, struct nmiaction *action) > +{ > + struct nmi_desc *desc = nmi_to_desc(type); > + struct nmiaction **a = &(desc->head); > + unsigned long flags; > + > + spin_lock_irqsave(&desc->lock, flags); > + > + /* > + * some handlers need to be executed first otherwise a fake > + * event confuses some handlers (kdump uses this flag) > + */ > + if (!(action->flags & NMI_FLAG_FIRST)) > + while ((*a) != NULL) > + a = &((*a)->next); > + > + action->next = *a; > + rcu_assign_pointer(*a, action); > + > + spin_unlock_irqrestore(&desc->lock, flags); > + return 0; > +} > + > +static struct nmiaction *__free_nmi(unsigned int type, const char *name) > +{ > + struct nmi_desc *desc = nmi_to_desc(type); > + struct nmiaction *n, **np = &(desc->head); > + unsigned long flags; > + > + spin_lock_irqsave(&desc->lock, flags); > + > + while ((*np) != NULL) { > + n = *np; > + > + /* > + * the name passed in to describe the nmi handler > + * is used as the lookup key > + */ > + if (!strcmp(n->name, name)) { > + WARN(in_nmi(), > + "Trying to free NMI (%s) from NMI context!\n", n->name); > + rcu_assign_pointer(*np, n->next); > + break; > + } > + np = &(n->next); > + } > + > + spin_unlock_irqrestore(&desc->lock, flags); > + synchronize_rcu(); > + return (*np); > +}
Probably not worth fixing, but if someone was silly enough to register with an already existing name we're up shit creek, right? :-)
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