The default_send_IPI_mask_logical() function uses the "flat" APIC mode
to send an IPI to a set of CPU's at once, but if that set happens to be
empty, some older local APIC's will apparently be rather unhappy. So
just warn if a caller gives us an empty mask, and ignore it.
This fixes a regression in 2.6.30.x, due to commit 4595f9620 ("x86:
change flush_tlb_others to take a const struct cpumask"), documented
here:
http://bugzilla.kernel.org/show_bug.cgi?id=13933
which causes a silent lock-up. It only seems to happen on PPro, P2, P3
and Athlon XP cores. Most developers sadly (or not so sadly, if you're
a developer..) have more modern CPU's. Also, on x86-64 we don't use the
flat APIC mode, so it would never trigger there even if the APIC didn't
like sending an empty IPI mask.
Reported-by: Pavel Vilim <wylda@volny.cz>
Reported-and-tested-by: Thomas Björnell <thomas.bjornell@gmail.com>
Reported-and-tested-by: Martin Rogge <marogge@onlinehome.de>
Cc: Mike Travis <travis@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We already use a lot of cpu_has_ helpers.
Lets do here the same for consistency.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090705160154.GB4791@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.
Move them to arch/x86/kernel/apic/*, and also remove
the 'gen' prefix from those which had it.
Also move APIC related functionality: the IO-APIC driver,
the NMI and the IPI code.
Signed-off-by: Ingo Molnar <mingo@elte.hu>