1 files changed, 7 insertions, 3 deletions

diff --git a/arch/powerpc/kernel/machine_kexec.c b/arch/powerpc/kernel/machine_kexec.c
index 6658a158995..9ce1672afb5 100644
--- a/arch/powerpc/kernel/machine_kexec.c
+++ b/arch/powerpc/kernel/machine_kexec.c
@@ -136,12 +136,16 @@ void __init reserve_crashkernel(void)
         crashk_res.start = KDUMP_KERNELBASE;
 #else
         if (!crashk_res.start) {
+#ifdef CONFIG_PPC64
                 /*
-                 * unspecified address, choose a region of specified size
-                 * can overlap with initrd (ignoring corruption when retained)
-                 * ppc64 requires kernel and some stacks to be in first segemnt
+                 * On 64bit we split the RMO in half but cap it at half of
+                 * a small SLB (128MB) since the crash kernel needs to place
+                 * itself and some stacks to be in the first segment.
                  */
+                crashk_res.start = min(0x80000000ULL, (ppc64_rma_size / 2));
+#else
                 crashk_res.start = KDUMP_KERNELBASE;
+#endif
         }
 
         crash_base = PAGE_ALIGN(crashk_res.start);