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| author | Yinghai Lu <yinghai@kernel.org> | 2009-05-02 10:40:57 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-05-12 12:22:06 +0200 |
| commit | 4797f6b021a3fa399942245d07a1feb30df81bb8 (patch) | |
| tree | aea4f0aec80786f8e5b4d55c9140add997a9a348 /arch/x86/include/asm/smp.h | |
| parent | 6cda3eb62ef42aa5acd649bf99c8db544e0f4051 (diff) | |
| download | linux-0-day-4797f6b021a3fa399942245d07a1feb30df81bb8.tar.gz linux-0-day-4797f6b021a3fa399942245d07a1feb30df81bb8.tar.xz | |
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.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index 19e0d88b966d7..6a84ed166aec1 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 |