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authorLinus Torvalds <torvalds@linux-foundation.org>2017-02-21 00:03:51 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-21 00:03:51 +0100
commit280d7a1edef214eefb1cb34915c73767355dd1b3 (patch)
tree4681f25ff0ef4d254269b9df99cd213a97ca354e /arch/x86/kernel/cpu/common.c
parentMerge branch 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux... (diff)
parentx86/fpu: Fix the "Giving up, no FPU found" test (diff)
downloadlinux-280d7a1edef214eefb1cb34915c73767355dd1b3.tar.xz
linux-280d7a1edef214eefb1cb34915c73767355dd1b3.zip
Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fpu updates from Ingo Molnar: "The main changes relate to fixes between (lack of) CPUID and FPU detection that should only affect old or weird CPUs, by Andy Lutomirski" * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu: Fix the "Giving up, no FPU found" test x86/fpu: Fix CPUID-less FPU detection x86/fpu: Fix "x86/fpu: Legacy x87 FPU detected" message x86/cpu: Re-apply forced caps every time CPU caps are re-read x86/cpu: Factor out application of forced CPU caps x86/cpu: Add X86_FEATURE_CPUID x86/fpu/xstate: Move XSAVES state init to a function
Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r--arch/x86/kernel/cpu/common.c34
1 files changed, 23 insertions, 11 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 5200adcaaac3..f07005e6f461 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -659,6 +659,16 @@ void cpu_detect(struct cpuinfo_x86 *c)
}
}
+static void apply_forced_caps(struct cpuinfo_x86 *c)
+{
+ int i;
+
+ for (i = 0; i < NCAPINTS; i++) {
+ c->x86_capability[i] &= ~cpu_caps_cleared[i];
+ c->x86_capability[i] |= cpu_caps_set[i];
+ }
+}
+
void get_cpu_cap(struct cpuinfo_x86 *c)
{
u32 eax, ebx, ecx, edx;
@@ -752,6 +762,13 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
c->x86_capability[CPUID_8000_000A_EDX] = cpuid_edx(0x8000000a);
init_scattered_cpuid_features(c);
+
+ /*
+ * Clear/Set all flags overridden by options, after probe.
+ * This needs to happen each time we re-probe, which may happen
+ * several times during CPU initialization.
+ */
+ apply_forced_caps(c);
}
static void identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
@@ -805,14 +822,12 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
memset(&c->x86_capability, 0, sizeof c->x86_capability);
c->extended_cpuid_level = 0;
- if (!have_cpuid_p())
- identify_cpu_without_cpuid(c);
-
/* cyrix could have cpuid enabled via c_identify()*/
if (have_cpuid_p()) {
cpu_detect(c);
get_cpu_vendor(c);
get_cpu_cap(c);
+ setup_force_cpu_cap(X86_FEATURE_CPUID);
if (this_cpu->c_early_init)
this_cpu->c_early_init(c);
@@ -822,6 +837,9 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
if (this_cpu->c_bsp_init)
this_cpu->c_bsp_init(c);
+ } else {
+ identify_cpu_without_cpuid(c);
+ setup_clear_cpu_cap(X86_FEATURE_CPUID);
}
setup_force_cpu_cap(X86_FEATURE_ALWAYS);
@@ -1039,10 +1057,7 @@ static void identify_cpu(struct cpuinfo_x86 *c)
this_cpu->c_identify(c);
/* Clear/Set all flags overridden by options, after probe */
- for (i = 0; i < NCAPINTS; i++) {
- c->x86_capability[i] &= ~cpu_caps_cleared[i];
- c->x86_capability[i] |= cpu_caps_set[i];
- }
+ apply_forced_caps(c);
#ifdef CONFIG_X86_64
c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
@@ -1103,10 +1118,7 @@ static void identify_cpu(struct cpuinfo_x86 *c)
* Clear/Set all flags overridden by options, need do it
* before following smp all cpus cap AND.
*/
- for (i = 0; i < NCAPINTS; i++) {
- c->x86_capability[i] &= ~cpu_caps_cleared[i];
- c->x86_capability[i] |= cpu_caps_set[i];
- }
+ apply_forced_caps(c);
/*
* On SMP, boot_cpu_data holds the common feature set between