x86/paravirt: make arch_flush_lazy_mmu/cpu disable preemption
Impact: avoid access to percpu vars in preempible context
They are intended to be used whenever there's the possibility
that there's some stale state which is going to be overwritten
with a queued update, or to force a state change when we may be
in lazy mode. Either way, we could end up calling it with
preemption enabled, so wrap the functions in their own little
preempt-disable section so they can be safely called in any
context (though preemption should never be enabled if we're actually
in a lazy state).
(Move out of line to avoid #include dependencies.)
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index ba3e2ff..a660ece 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -1352,14 +1352,7 @@
PVOP_VCALL0(pv_cpu_ops.lazy_mode.leave);
}
-static inline void arch_flush_lazy_cpu_mode(void)
-{
- if (unlikely(paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU)) {
- arch_leave_lazy_cpu_mode();
- arch_enter_lazy_cpu_mode();
- }
-}
-
+void arch_flush_lazy_cpu_mode(void);
#define __HAVE_ARCH_ENTER_LAZY_MMU_MODE
static inline void arch_enter_lazy_mmu_mode(void)
@@ -1372,13 +1365,7 @@
PVOP_VCALL0(pv_mmu_ops.lazy_mode.leave);
}
-static inline void arch_flush_lazy_mmu_mode(void)
-{
- if (unlikely(paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU)) {
- arch_leave_lazy_mmu_mode();
- arch_enter_lazy_mmu_mode();
- }
-}
+void arch_flush_lazy_mmu_mode(void);
static inline void __set_fixmap(unsigned /* enum fixed_addresses */ idx,
unsigned long phys, pgprot_t flags)