x86/mm: Rename is_kernel_text to __is_kernel_text

The kbuild test robot reported compile issue on x86 in one of
the following patches that adds <linux/kallsyms.h> include into
<linux/bpf.h>, which is picked up by init_32.c object.

The problem is that <linux/kallsyms.h> defines global function
is_kernel_text which colides with the static function of the
same name defined in init_32.c:

  $ make ARCH=i386
  ...
  >> arch/x86/mm/init_32.c:241:19: error: redefinition of 'is_kernel_text'
    static inline int is_kernel_text(unsigned long addr)
                      ^~~~~~~~~~~~~~
   In file included from include/linux/bpf.h:21:0,
                    from include/linux/bpf-cgroup.h:5,
                    from include/linux/cgroup-defs.h:22,
                    from include/linux/cgroup.h:28,
                    from include/linux/hugetlb.h:9,
                    from arch/x86/mm/init_32.c:18:
   include/linux/kallsyms.h:31:19: note: previous definition of 'is_kernel_text' was here
    static inline int is_kernel_text(unsigned long addr)

Renaming the init_32.c is_kernel_text function to __is_kernel_text.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-2-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 23df488..eb6ede2 100644 (file)
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -238,7 +238,11 @@ page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
        }
 }
 
-static inline int is_kernel_text(unsigned long addr)
+/*
+ * The <linux/kallsyms.h> already defines is_kernel_text,
+ * using '__' prefix not to get in conflict.
+ */
+static inline int __is_kernel_text(unsigned long addr)
 {
        if (addr >= (unsigned long)_text && addr <= (unsigned long)__init_end)
                return 1;
@@ -328,8 +332,8 @@ repeat:
                                addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE +
                                        PAGE_OFFSET + PAGE_SIZE-1;
 
-                               if (is_kernel_text(addr) ||
-                                   is_kernel_text(addr2))
+                               if (__is_kernel_text(addr) ||
+                                   __is_kernel_text(addr2))
                                        prot = PAGE_KERNEL_LARGE_EXEC;
 
                                pages_2m++;
@@ -354,7 +358,7 @@ repeat:
                                 */
                                pgprot_t init_prot = __pgprot(PTE_IDENT_ATTR);
 
-                               if (is_kernel_text(addr))
+                               if (__is_kernel_text(addr))
                                        prot = PAGE_KERNEL_EXEC;
 
                                pages_4k++;
@@ -881,7 +885,7 @@ static void mark_nxdata_nx(void)
         */
        unsigned long start = PFN_ALIGN(_etext);
        /*
-        * This comes from is_kernel_text upper limit. Also HPAGE where used:
+        * This comes from __is_kernel_text upper limit. Also HPAGE where used:
         */
        unsigned long size = (((unsigned long)__init_end + HPAGE_SIZE) & HPAGE_MASK) - start;