2 files changed, 37 insertions, 6 deletions

diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index 621b959e1dbf..b5a27bd77669 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -123,6 +123,12 @@ static inline void reset_lazy_tlbstate(void)
 {
 }
 
+static inline void flush_tlb_kernel_range(unsigned long start,
+                                          unsigned long end)
+{
+        flush_tlb_all();
+}
+
 #else  /* SMP */
 
 #include <asm/smp.h>
@@ -139,6 +145,7 @@ extern void flush_tlb_current_task(void);
 extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
 extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
                                 unsigned long end, unsigned long vmflag);
+extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
 
 #define flush_tlb()     flush_tlb_current_task()
 
@@ -168,10 +175,4 @@ static inline void reset_lazy_tlbstate(void)
         native_flush_tlb_others(mask, mm, start, end)
 #endif
 
-static inline void flush_tlb_kernel_range(unsigned long start,
-                                          unsigned long end)
-{
-        flush_tlb_all();
-}
-
 #endif /* _ASM_X86_TLBFLUSH_H */
diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 2b5f506a7655..613cd83e8c0c 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -264,6 +264,36 @@ void flush_tlb_all(void)
         on_each_cpu(do_flush_tlb_all, NULL, 1);
 }
 
+static void do_kernel_range_flush(void *info)
+{
+        struct flush_tlb_info *f = info;
+        unsigned long addr;
+
+        /* flush range by one by one 'invlpg' */
+        for (addr = f->flush_start; addr < f->flush_end; addr += PAGE_SIZE)
+                __flush_tlb_single(addr);
+}
+
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+        unsigned act_entries;
+        struct flush_tlb_info info;
+
+        /* In modern CPU, last level tlb used for both data/ins */
+        act_entries = tlb_lld_4k[ENTRIES];
+
+        /* Balance as user space task's flush, a bit conservative */
+        if (end == TLB_FLUSH_ALL || tlb_flushall_shift == -1 ||
+                (end - start) >> PAGE_SHIFT > act_entries >> tlb_flushall_shift)
+
+                on_each_cpu(do_flush_tlb_all, NULL, 1);
+        else {
+                info.flush_start = start;
+                info.flush_end = end;
+                on_each_cpu(do_kernel_range_flush, &info, 1);
+        }
+}
+
 #ifdef CONFIG_DEBUG_TLBFLUSH
 static ssize_t tlbflush_read_file(struct file *file, char __user *user_buf,
                              size_t count, loff_t *ppos)