diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index c25f160bb997..47cec207e557 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -472,7 +472,7 @@ long plpar_hcall_norets_notrace(unsigned long opcode, ...);
  * Used for all but the craziest of phyp interfaces (see plpar_hcall9)
  */
 #define PLPAR_HCALL_BUFSIZE 4
-long plpar_hcall(unsigned long opcode, unsigned long *retbuf, ...);
+long plpar_hcall(unsigned long opcode, unsigned long retbuf[static PLPAR_HCALL_BUFSIZE], ...);
 
 /**
  * plpar_hcall_raw: - Make a hypervisor call without calculating hcall stats
@@ -486,7 +486,7 @@ long plpar_hcall(unsigned long opcode, unsigned long *retbuf, ...);
  * plpar_hcall, but plpar_hcall_raw works in real mode and does not
  * calculate hypervisor call statistics.
  */
-long plpar_hcall_raw(unsigned long opcode, unsigned long *retbuf, ...);
+long plpar_hcall_raw(unsigned long opcode, unsigned long retbuf[static PLPAR_HCALL_BUFSIZE], ...);
 
 /**
  * plpar_hcall9: - Make a pseries hypervisor call with up to 9 return arguments
@@ -497,8 +497,8 @@ long plpar_hcall_raw(unsigned long opcode, unsigned long *retbuf, ...);
  * PLPAR_HCALL9_BUFSIZE to size the return argument buffer.
  */
 #define PLPAR_HCALL9_BUFSIZE 9
-long plpar_hcall9(unsigned long opcode, unsigned long *retbuf, ...);
-long plpar_hcall9_raw(unsigned long opcode, unsigned long *retbuf, ...);
+long plpar_hcall9(unsigned long opcode, unsigned long retbuf[static PLPAR_HCALL9_BUFSIZE], ...);
+long plpar_hcall9_raw(unsigned long opcode, unsigned long retbuf[static PLPAR_HCALL9_BUFSIZE], ...);
 
 struct hvcall_mpp_data {
 	unsigned long entitled_mem;