summaryrefslogtreecommitdiffstats
path: root/arch/x86/include/asm/smp.h
diff options
context:
space:
mode:
authorYinghai Lu <yinghai@kernel.org>2009-05-02 10:40:57 -0700
committerIngo Molnar <mingo@elte.hu>2009-05-12 12:22:06 +0200
commit4797f6b021a3fa399942245d07a1feb30df81bb8 (patch)
treeaea4f0aec80786f8e5b4d55c9140add997a9a348 /arch/x86/include/asm/smp.h
parent6cda3eb62ef42aa5acd649bf99c8db544e0f4051 (diff)
x86: read apic ID in the !acpi_lapic case
Ed found that on 32-bit, boot_cpu_physical_apicid is not read right, when the mptable is broken. Interestingly, actually three paths use/set it: 1. acpi: at that time that is already read from reg 2. mptable: only read from mptable 3. no madt, and no mptable, that use default apic id 0 for 64-bit, -1 for 32-bit so we could read the apic id for the 2/3 path. We trust the hardware register more than we trust a BIOS data structure (the mptable). We can also avoid the double set_fixmap() when acpi_lapic is used, and also need to move cpu_has_apic earlier and call apic_disable(). Also when need to update the apic id, we'd better read and set the apic version as well - so that quirks are applied precisely. v2: make path 3 with 64bit, use -1 as apic id, so could read it later. v3: fix whitespace problem pointed out by Ed Swierk v5: fix boot crash [ Impact: get correct apic id for bsp other than acpi path ] Reported-by: Ed Swierk <eswierk@aristanetworks.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> LKML-Reference: <49FC85A9.2070702@kernel.org> [ v4: sanity-check in the ACPI case too ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/include/asm/smp.h')
-rw-r--r--arch/x86/include/asm/smp.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
index 19e0d88b966..6a84ed166ae 100644
--- a/arch/x86/include/asm/smp.h
+++ b/arch/x86/include/asm/smp.h
@@ -180,7 +180,7 @@ extern int safe_smp_processor_id(void);
static inline int logical_smp_processor_id(void)
{
/* we don't want to mark this access volatile - bad code generation */
- return GET_APIC_LOGICAL_ID(*(u32 *)(APIC_BASE + APIC_LDR));
+ return GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
}
#endif