powerpc/powernv: Skip registering log region when CONFIG_PRINTK=n

When CONFIG_PRINTK=n, log_buf_addr_get() returns NULL and log_buf_len_get()
return 0. Check for these return values and skip registering the dump buffer.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Reviewed-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 6 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index f10b9ec8c1f5..1db119f0f4ee 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -667,7 +667,13 @@ static void __init opal_dump_region_init(void)
 
         /* Register kernel log buffer */
         addr = log_buf_addr_get();
+        if (addr == NULL)
+                return;
+
         size = log_buf_len_get();
+        if (size == 0)
+                return;
+
         rc = opal_register_dump_region(OPAL_DUMP_REGION_LOG_BUF,
                                        __pa(addr), size);
         /* Don't warn if this is just an older OPAL that doesn't