android_kernel_xiaomi_sm8350/include/asm-x86/tlbflush.h
Ingo Molnar b1979a5fda x86: prevent PGE flush from interruption/preemption
CR4 manipulation is not protected against interrupts and preemption,
but KVM uses smp_function_call to manipulate the X86_CR4_VMXE bit
either from the CPU hotplug code or from the kvm_init call.

We need to protect the CR4 manipulation from both interrupts and
preemption.

Original bug report: http://lkml.org/lkml/2008/5/7/48
Bugzilla entry: http://bugzilla.kernel.org/show_bug.cgi?id=10642

This is not a regression from 2.6.25, it's a long standing and hard to
trigger bug.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-23 18:16:15 +02:00

169 lines
3.8 KiB
C

#ifndef _ASM_X86_TLBFLUSH_H
#define _ASM_X86_TLBFLUSH_H
#include <linux/mm.h>
#include <linux/sched.h>
#include <asm/processor.h>
#include <asm/system.h>
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#define __flush_tlb() __native_flush_tlb()
#define __flush_tlb_global() __native_flush_tlb_global()
#define __flush_tlb_single(addr) __native_flush_tlb_single(addr)
#endif
static inline void __native_flush_tlb(void)
{
write_cr3(read_cr3());
}
static inline void __native_flush_tlb_global(void)
{
unsigned long flags;
unsigned long cr4;
/*
* Read-modify-write to CR4 - protect it from preemption and
* from interrupts. (Use the raw variant because this code can
* be called from deep inside debugging code.)
*/
raw_local_irq_save(flags);
cr4 = read_cr4();
/* clear PGE */
write_cr4(cr4 & ~X86_CR4_PGE);
/* write old PGE again and flush TLBs */
write_cr4(cr4);
raw_local_irq_restore(flags);
}
static inline void __native_flush_tlb_single(unsigned long addr)
{
asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
}
static inline void __flush_tlb_all(void)
{
if (cpu_has_pge)
__flush_tlb_global();
else
__flush_tlb();
}
static inline void __flush_tlb_one(unsigned long addr)
{
if (cpu_has_invlpg)
__flush_tlb_single(addr);
else
__flush_tlb();
}
#ifdef CONFIG_X86_32
# define TLB_FLUSH_ALL 0xffffffff
#else
# define TLB_FLUSH_ALL -1ULL
#endif
/*
* TLB flushing:
*
* - flush_tlb() flushes the current mm struct TLBs
* - flush_tlb_all() flushes all processes TLBs
* - flush_tlb_mm(mm) flushes the specified mm context TLB's
* - flush_tlb_page(vma, vmaddr) flushes one page
* - flush_tlb_range(vma, start, end) flushes a range of pages
* - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
* - flush_tlb_others(cpumask, mm, va) flushes TLBs on other cpus
*
* ..but the i386 has somewhat limited tlb flushing capabilities,
* and page-granular flushes are available only on i486 and up.
*
* x86-64 can only flush individual pages or full VMs. For a range flush
* we always do the full VM. Might be worth trying if for a small
* range a few INVLPGs in a row are a win.
*/
#ifndef CONFIG_SMP
#define flush_tlb() __flush_tlb()
#define flush_tlb_all() __flush_tlb_all()
#define local_flush_tlb() __flush_tlb()
static inline void flush_tlb_mm(struct mm_struct *mm)
{
if (mm == current->active_mm)
__flush_tlb();
}
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long addr)
{
if (vma->vm_mm == current->active_mm)
__flush_tlb_one(addr);
}
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
if (vma->vm_mm == current->active_mm)
__flush_tlb();
}
static inline void native_flush_tlb_others(const cpumask_t *cpumask,
struct mm_struct *mm,
unsigned long va)
{
}
#else /* SMP */
#include <asm/smp.h>
#define local_flush_tlb() __flush_tlb()
extern void flush_tlb_all(void);
extern void flush_tlb_current_task(void);
extern void flush_tlb_mm(struct mm_struct *);
extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
#define flush_tlb() flush_tlb_current_task()
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
flush_tlb_mm(vma->vm_mm);
}
void native_flush_tlb_others(const cpumask_t *cpumask, struct mm_struct *mm,
unsigned long va);
#define TLBSTATE_OK 1
#define TLBSTATE_LAZY 2
#ifdef CONFIG_X86_32
struct tlb_state {
struct mm_struct *active_mm;
int state;
char __cacheline_padding[L1_CACHE_BYTES-8];
};
DECLARE_PER_CPU(struct tlb_state, cpu_tlbstate);
#endif
#endif /* SMP */
#ifndef CONFIG_PARAVIRT
#define flush_tlb_others(mask, mm, va) native_flush_tlb_others(&mask, mm, va)
#endif
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
flush_tlb_all();
}
#endif /* _ASM_X86_TLBFLUSH_H */