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xen/apic: Return the APIC ID (and version) for CPU 0.

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On x86_64 on AMD machines where the first APIC_ID is not zero, we get:

ACPI: LAPIC (acpi_id[0x01] lapic_id[0x10] enabled)
BIOS bug: APIC version is 0 for CPU 1/0x10, fixing up to 0x10
BIOS bug: APIC version mismatch, boot CPU: 0, CPU 1: version 10

which means that when the ACPI processor driver loads and
tries to parse the _Pxx states it fails to do as, as it
ends up calling acpi_get_cpuid which does this:

for_each_possible_cpu(i) {
        if (cpu_physical_id(i) == apic_id)
                return i;
}

And the bootup CPU, has not been found so it fails and returns -1
for the first CPU - which then subsequently in the loop that
"acpi_processor_get_info" does results in returning an error, which
means that "acpi_processor_add" failing and per_cpu(processor)
is never set (and is NULL).

That means that when xen-acpi-processor tries to load (much much
later on) and parse the P-states it gets -ENODEV from
acpi_processor_register_performance() (which tries to read
the per_cpu(processor)) and fails to parse the data.

Reported-by-and-Tested-by:  Stefan Bader <stefan.bader@canonical.com>
Suggested-by:  Boris Ostrovsky <boris.ostrovsky@amd.com>
[v2: Bit-shift APIC ID by 24 bits]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Konrad Rzeszutek Wilk 2012-05-02 15:04:51 -04:00
parent a7a97c6394
commit 558daa289a
1 changed files with 34 additions and 1 deletions
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35
arch/x86/xen/enlighten.c
View File

@ -809,9 +809,40 @@ static void xen_io_delay(void)
}
#ifdef CONFIG_X86_LOCAL_APIC
static unsigned long xen_set_apic_id(unsigned int x)
{
WARN_ON(1);
return x;
}
static unsigned int xen_get_apic_id(unsigned long x)
{
return ((x)>>24) & 0xFFu;
}
static u32 xen_apic_read(u32 reg)
{
return 0;
struct xen_platform_op op = {
.cmd = XENPF_get_cpuinfo,
.interface_version = XENPF_INTERFACE_VERSION,
.u.pcpu_info.xen_cpuid = 0,
};
int ret = 0;
/* Shouldn't need this as APIC is turned off for PV, and we only
* get called on the bootup processor. But just in case. */
if (!xen_initial_domain() || smp_processor_id())
return 0;
if (reg == APIC_LVR)
return 0x10;
if (reg != APIC_ID)
return 0;
ret = HYPERVISOR_dom0_op(&op);
if (ret)
return 0;
return op.u.pcpu_info.apic_id << 24;
}
static void xen_apic_write(u32 reg, u32 val)
@ -849,6 +880,8 @@ static void set_xen_basic_apic_ops(void)
apic->icr_write = xen_apic_icr_write;
apic->wait_icr_idle = xen_apic_wait_icr_idle;
apic->safe_wait_icr_idle = xen_safe_apic_wait_icr_idle;
apic->set_apic_id = xen_set_apic_id;
apic->get_apic_id = xen_get_apic_id;
}
#endif