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diff --git a/static/netbsd/man9/man9.x86/nmi.9 b/static/netbsd/man9/man9.x86/nmi.9 new file mode 100644 index 00000000..708dba39 --- /dev/null +++ b/static/netbsd/man9/man9.x86/nmi.9 @@ -0,0 +1,135 @@ +.\" $NetBSD: nmi.9,v 1.5 2014/03/18 18:20:40 riastradh Exp $ +.\" +.\" Copyright (c) 2010 The NetBSD Foundation, Inc. +.\" All rights reserved. +.\" +.\" This code is derived from software contributed to The NetBSD Foundation +.\" by David Young. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS +.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS +.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +.\" POSSIBILITY OF SUCH DAMAGE. +.\" +.Dd March 17, 2011 +.Dt NMI 9 x86 +.Os +.Sh NAME +.Nm nmi , +.Nm nmi_establish , +.Nm nmi_disestablish , +.Nd NMI +.Sh SYNOPSIS +.In x86/nmi.h +.Ft nmi_handler_t * +.Fn nmi_establish "int (*func)(const struct trapframe *, void *)" "void *arg" +.Ft void +.Fn nmi_disestablish "nmi_handler_t *handle" +.Sh DESCRIPTION +The +.Nm +interface lets the kernel establish handlers for x86 Non-Maskable +Interrupts (NMIs). +An NMI signals to the processor an exception on a processor, memory +controller, or I/O bus that is irrecoverable or else needs attention +at a high priority. +A +.Dq "debug switch" +or a performance/watchdog timer may also trigger an NMI. +.Pp +An NMI handler will run to completion on the same processor where +it began without being preempted by any thread or interrupt except +for another NMI. +An NMI handler must prepare for re-entry. +An NMI handler may run simultaneously on more than one CPU. +.Pp +Synchronizing access to a shared data structure from +an NMI handler is a different challenge than synchronizing access +from hardware/software interrupt routines or from kernel threads. +An NMI handler may not perform any operation that may sleep, acquire +a mutex, or schedule a software interrupt. +An NMI handler may use +.Xr atomic_ops 3 . +An NMI handler may reference per-CPU storage +.Po +.Xr percpu 9 +.Pc . +.Pp +An NMI handler may not write to the kernel message buffer. +.Sh FUNCTIONS +.Bl -tag -width compact +.It Fn nmi_establish "func" "arg" +Call this in thread context to establish a handler for non-maskable +interrupts. +Establish +.Fa func +as one of the handler functions to call when an NMI occurs. +Where +.Fa tf +is a +.Vt struct trapframe +representation of the processor context where the NMI was received, +and +.Fa arg +is the argument to +.Fn nmi_establish , +the kernel will call +.Fo (*func) +.Fa tf +.Fa arg +.Fc +every time an NMI occurs until the handler is removed with +.Fn nmi_disestablish . +.Fa func +should return non-zero if it handled a condition that causes +NMI, or zero if it did not. +If, for a given NMI, all handlers return zero, the system will +panic or enter the kernel debugger, +.Xr ddb 4 . +.Fn nmi_establish +returns +.Dv NULL +on failure, and a handle for the NMI handler on success. +.It Fn nmi_disestablish "handle" +Call this in thread context to stop the kernel from calling an NMI +handler. +Indicate the handler to disestablish with the +.Fa handle +returned by +.Fn nmi_establish . +.El +.Sh CODE REFERENCES +The +.Nm +interface is implemented within the file +.Pa sys/arch/x86/x86/nmi.c . +.\" .Sh EXAMPLES +.Sh SEE ALSO +.Xr atomic_ops 3 , +.Xr ddb 4 +.Sh HISTORY +The +.Nm +interface first appeared in +.Nx 6.0 . +.Sh AUTHORS +.An YAMAMOTO Takashi Aq Mt yamt@NetBSD.org +.\" .Sh CAVEATS +.\" .Sh BUGS +.\" .Sh SECURITY CONSIDERATIONS |