summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJuergen Gross <jgross@suse.com>2017-04-12 12:37:00 +0200
committerJuergen Gross <jgross@suse.com>2017-05-02 11:14:05 +0200
commitea01598b4bc453ed513e9d482a43c14557042ec9 (patch)
treeeb66edc411c539f50193f4a4e5f5658a811251b2
parentb778d6bf63e0a07ceb2258ce9bd996dbaaa11bfa (diff)
x86/xen: use capabilities instead of fake cpuid values for mwait
When running as pv domain xen_cpuid() is being used instead of native_cpuid(). In xen_cpuid() the mwait feature is indicated to be present or not by special casing the related cpuid leaf. Instead of delivering fake cpuid values use the cpu capability bit for mwait instead. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
-rw-r--r--arch/x86/xen/enlighten_pv.c11
1 files changed, 5 insertions, 6 deletions
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 3196961862bc..d43382284ada 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -167,7 +167,6 @@ xen_running_on_version_or_later(unsigned int major, unsigned int minor)
static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0;
-static __read_mostly unsigned int cpuid_leaf1_ecx_set_mask;
static __read_mostly unsigned int cpuid_leaf5_ecx_val;
static __read_mostly unsigned int cpuid_leaf5_edx_val;
@@ -176,7 +175,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
{
unsigned maskebx = ~0;
unsigned maskecx = ~0;
- unsigned setecx = 0;
/*
* Mask out inconvenient features, to try and disable as many
* unsupported kernel subsystems as possible.
@@ -184,7 +182,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
switch (*ax) {
case 1:
maskecx = cpuid_leaf1_ecx_mask;
- setecx = cpuid_leaf1_ecx_set_mask;
break;
case CPUID_MWAIT_LEAF:
@@ -210,7 +207,6 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
*bx &= maskebx;
*cx &= maskecx;
- *cx |= setecx;
}
STACK_FRAME_NON_STANDARD(xen_cpuid); /* XEN_EMULATE_PREFIX */
@@ -303,8 +299,6 @@ static void __init xen_init_cpuid_mask(void)
/* Xen will set CR4.OSXSAVE if supported and not disabled by force */
if ((cx & xsave_mask) != xsave_mask)
cpuid_leaf1_ecx_mask &= ~xsave_mask; /* disable XSAVE & OSXSAVE */
- if (xen_check_mwait())
- cpuid_leaf1_ecx_set_mask = (1 << (X86_FEATURE_MWAIT % 32));
}
static void __init xen_init_capabilities(void)
@@ -318,6 +312,11 @@ static void __init xen_init_capabilities(void)
if (!xen_initial_domain())
setup_clear_cpu_cap(X86_FEATURE_ACPI);
+
+ if (xen_check_mwait())
+ setup_force_cpu_cap(X86_FEATURE_MWAIT);
+ else
+ setup_clear_cpu_cap(X86_FEATURE_MWAIT);
}
static void xen_set_debugreg(int reg, unsigned long val)