diff --git a/arch/powerpc/configs/ppc64_defconfig b/arch/powerpc/configs/ppc64_defconfig
index 861471d..886b237 100644
--- a/arch/powerpc/configs/ppc64_defconfig
+++ b/arch/powerpc/configs/ppc64_defconfig
@@ -10,6 +10,8 @@
 CONFIG_TASK_DELAY_ACCT=y
 CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
+CONFIG_LOG_BUF_SHIFT=18
+CONFIG_LOG_CPU_MAX_BUF_SHIFT=13
 CONFIG_CGROUPS=y
 CONFIG_CPUSETS=y
 CONFIG_BLK_DEV_INITRD=y