linux/include/asm-i386/mach-default/mach_ipi.h
Keith Owens e77deacb7b [PATCH] x86_64: Avoid broadcasting NMI IPIs
On some i386/x86_64 systems, sending an NMI IPI as a broadcast will
reset the system.  This seems to be a BIOS bug which affects machines
where one or more cpus are not under OS control.  It occurs on HT
systems with a version of the OS that is not compiled without HT
support.  It also occurs when a system is booted with max_cpus=n where
2 <= n < cpus known to the BIOS.  The fix is to always send NMI IPI as
a mask instead of as a broadcast.

Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 10:48:22 -07:00

55 lines
1.2 KiB
C

#ifndef __ASM_MACH_IPI_H
#define __ASM_MACH_IPI_H
/* Avoid include hell */
#define NMI_VECTOR 0x02
void send_IPI_mask_bitmask(cpumask_t mask, int vector);
void __send_IPI_shortcut(unsigned int shortcut, int vector);
extern int no_broadcast;
static inline void send_IPI_mask(cpumask_t mask, int vector)
{
send_IPI_mask_bitmask(mask, vector);
}
static inline void __local_send_IPI_allbutself(int vector)
{
if (no_broadcast || vector == NMI_VECTOR) {
cpumask_t mask = cpu_online_map;
cpu_clear(smp_processor_id(), mask);
send_IPI_mask(mask, vector);
} else
__send_IPI_shortcut(APIC_DEST_ALLBUT, vector);
}
static inline void __local_send_IPI_all(int vector)
{
if (no_broadcast || vector == NMI_VECTOR)
send_IPI_mask(cpu_online_map, vector);
else
__send_IPI_shortcut(APIC_DEST_ALLINC, vector);
}
static inline void send_IPI_allbutself(int vector)
{
/*
* if there are no other CPUs in the system then we get an APIC send
* error if we try to broadcast, thus avoid sending IPIs in this case.
*/
if (!(num_online_cpus() > 1))
return;
__local_send_IPI_allbutself(vector);
return;
}
static inline void send_IPI_all(int vector)
{
__local_send_IPI_all(vector);
}
#endif /* __ASM_MACH_IPI_H */