[PATCH] ppc64: Don't panic when early __ioremap fails

Early calls to __ioremap() will panic if the hash insertion fails. This
patch makes them return NULL instead. It happens with some pSeries users
who enabled CONFIG_BOOTX_TEXT. The later is getting an incorrect address
for the fame buffer and the hash insertion fails. With this patch, it
will display an error instead of crashing at boot.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 900842451bd3..c7f7bb6f30b3 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -122,8 +122,11 @@ static int map_io_page(unsigned long ea, unsigned long pa, int flags)
                  *
                  */
                 if (htab_bolt_mapping(ea, ea + PAGE_SIZE, pa, flags,
-                                      mmu_virtual_psize))
-                        panic("Can't map bolted IO mapping");
+                                      mmu_virtual_psize)) {
+                        printk(KERN_ERR "Failed to do bolted mapping IO "
+                               "memory at %016lx !\n", pa);
+                        return -ENOMEM;
+                }
         }
         return 0;
 }