x86/boot/compressed/64: Check return value of kernel_ident_mapping_init()

The function can fail to create an identity mapping, check for that
and bail out if it happens.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907131613.12703-22-joro@8bytes.org

diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c
index b4f2a5f..aa91beb 100644 (file)
--- a/arch/x86/boot/compressed/ident_map_64.c
+++ b/arch/x86/boot/compressed/ident_map_64.c
@@ -91,6 +91,8 @@ static struct x86_mapping_info mapping_info;
  */
 static void add_identity_map(unsigned long start, unsigned long end)
 {
+       int ret;
+
        /* Align boundary to 2M. */
        start = round_down(start, PMD_SIZE);
        end = round_up(end, PMD_SIZE);
@@ -98,8 +100,9 @@ static void add_identity_map(unsigned long start, unsigned long end)
                return;
 
        /* Build the mapping. */
-       kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt,
-                                 start, end);
+       ret = kernel_ident_mapping_init(&mapping_info, (pgd_t *)top_level_pgt, start, end);
+       if (ret)
+               error("Error: kernel_ident_mapping_init() failed\n");
 }
 
 /* Locates and clears a region for a new top level page table. */