linux/arch/x86
Cyrill Gorcunov 103428e57b x86, apic: Fix dummy apic read operation together with broken MP handling
Ingo Molnar reported that read_apic is buggy novadays:

[    0.000000] Using APIC driver default
[    0.000000] SMP: Allowing 1 CPUs, 0 hotplug CPUs
[    0.000000] Local APIC disabled by BIOS -- you can enable it with "lapic"
[    0.000000] APIC: disable apic facility
[    0.000000] ------------[ cut here ]------------
[    0.000000] WARNING: at arch/x86/kernel/apic/apic.c:254 native_apic_read_dummy+0x2d/0x3b()
[    0.000000] Hardware name: HP OmniBook PC

Indeed we still rely on apic->read operation for SMP compiled
kernel. And instead of disfigure the SMP code with #ifdef we
allow to call apic->read. To capture any unexpected results
we check for apic->read being called for sane reason via
WARN_ON_ONCE but(!) instead of OR we should use AND logical
operation (thanks Yinghai for spotting the root of the problem).

Along with that we could be have bad MP table and we are
to fix it that way no SMP started and no complains about
BIOS bug if apic was just disabled via command line.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <20090607124840.GD4547@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-07 16:08:05 +02:00
..
boot x86, relocs: ignore R_386_NONE in kernel relocation entries 2009-05-25 22:52:49 -07:00
configs x86/irq: remove leftover code from NUMA_MIGRATE_IRQ_DESC 2009-04-28 12:21:15 +02:00
crypto crypto: aes-ni - Add support to Intel AES-NI instructions for x86_64 platform 2009-02-18 16:48:06 +08:00
ia32 Separate out common fstatat code into vfs_fstatat 2009-04-20 23:02:51 -04:00
include/asm Merge branch 'x86/cpufeature' into irq/numa 2009-06-01 22:30:01 +02:00
kernel x86, apic: Fix dummy apic read operation together with broken MP handling 2009-06-07 16:08:05 +02:00
kvm KVM: Fix PDPTR reloading on CR4 writes 2009-05-25 20:00:53 +03:00
lguest x86/irq: change irq_desc_alloc() to take node instead of cpu 2009-04-28 12:21:17 +02:00
lib x86: memcpy, clean up 2009-03-12 12:21:17 +01:00
math-emu Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2 2009-03-27 17:28:43 +01:00
mm x86: ignore VM_LOCKED when determining if hugetlb-backed page tables can be shared or not 2009-05-29 08:40:03 -07:00
oprofile x86, 32-bit: fix kernel_trap_sp() 2009-05-12 00:39:52 +02:00
pci x86, apic: introduce io_apic_irq_attr 2009-05-18 08:38:55 +02:00
power x86: disable stack-protector for __restore_processor_state() 2009-04-03 19:48:41 +02:00
vdso x86: gettimeofday() vDSO: fix segfault when tv == NULL 2009-04-30 12:31:45 +02:00
video
xen x86: Fix performance regression caused by paravirt_ops on native kernels 2009-05-15 20:07:42 +02:00
Kconfig Merge branch 'linus' into irq/numa 2009-06-01 21:06:21 +02:00
Kconfig.cpu x86: disable X86_PTRACE_BTS for now 2009-04-15 23:15:14 +02:00
Kconfig.debug generic debug pagealloc: build fix 2009-04-02 19:04:48 -07:00
Makefile x86, kbuild: make "make install" not depend on vmlinux 2009-04-17 22:43:12 +02:00
Makefile_32.cpu x86: merge winchip-2 and winchip-2a cpu choices 2008-10-13 10:22:48 +02:00