diff options
| author | Keith Owens <kaos@sgi.com> | 2006-06-26 13:59:56 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-26 10:48:22 -0700 |
| commit | e77deacb7b078156fcadf27b838a4ce1a65eda04 (patch) | |
| tree | e594ce9a9f65c45e19cfb3b8417c614dd2eb5386 /arch/x86_64/kernel/genapic_flat.c | |
| parent | 704fc59e1d056de80beaf30174bc8e0b1682efbb (diff) | |
| download | lwn-e77deacb7b078156fcadf27b838a4ce1a65eda04.tar.gz lwn-e77deacb7b078156fcadf27b838a4ce1a65eda04.zip | |
[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>
Diffstat (limited to 'arch/x86_64/kernel/genapic_flat.c')
| -rw-r--r-- | arch/x86_64/kernel/genapic_flat.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/arch/x86_64/kernel/genapic_flat.c b/arch/x86_64/kernel/genapic_flat.c index c66ca7b1d31a..21c7066e236a 100644 --- a/arch/x86_64/kernel/genapic_flat.c +++ b/arch/x86_64/kernel/genapic_flat.c @@ -78,22 +78,29 @@ static void flat_send_IPI_mask(cpumask_t cpumask, int vector) static void flat_send_IPI_allbutself(int vector) { -#ifndef CONFIG_HOTPLUG_CPU - if (((num_online_cpus()) - 1) >= 1) - __send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL); +#ifdef CONFIG_HOTPLUG_CPU + int hotplug = 1; #else - cpumask_t allbutme = cpu_online_map; + int hotplug = 0; +#endif + if (hotplug || vector == NMI_VECTOR) { + cpumask_t allbutme = cpu_online_map; - cpu_clear(smp_processor_id(), allbutme); + cpu_clear(smp_processor_id(), allbutme); - if (!cpus_empty(allbutme)) - flat_send_IPI_mask(allbutme, vector); -#endif + if (!cpus_empty(allbutme)) + flat_send_IPI_mask(allbutme, vector); + } else if (num_online_cpus() > 1) { + __send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL); + } } static void flat_send_IPI_all(int vector) { - __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL); + if (vector == NMI_VECTOR) + flat_send_IPI_mask(cpu_online_map, vector); + else + __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL); } static int flat_apic_id_registered(void) |