Skip to contentSkip to conversation

FAILED: patch "[PATCH] powerpc: Convert cmp to cmpd in idle enter sequence" failed to apply to 4.4-stable tree

PATCH [email protected] 1 participant 1 message Nov 7, 2016

Subsystems (2)
lore
Share & tools
lore

[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

Quoted 1 line

From 80f23935cadb1c654e81951f5a8b7ceae0acc1b4 Mon Sep 17 00:00:00 2001

From: Segher Boessenkool <[email protected]>
Date: Thu, 6 Oct 2016 13:42:19 +0000
Subject: [PATCH] powerpc: Convert cmp to cmpd in idle enter sequence

PowerPC's "cmp" instruction has four operands. Normally people write "cmpw" or "cmpd" for the second cmp operand 0 or 1. But, frequently people forget, and write "cmp" with just three operands.

With older binutils this is silently accepted as if this was "cmpw", while often "cmpd" is wanted. With newer binutils GAS will complain about this for 64-bit code. For 32-bit code it still silently assumes "cmpw" is what is meant.

In this instance the code comes directly from ISA v2.07, including the cmp, but cmpd is correct. Backport to stable so that new toolchains can build old kernels.

Fixes 948cf67c4726 ("powerpc: Add NAP mode support on Power7 in HV mode")
arch/powerpc/include/asm/cpuidle.h +1 -1
index 01b8a13f0224..3919332965af 100644
@@ -26,7 +26,7 @@ extern u64 pnv_first_deep_stop_state;
 	std	r0,0(r1);					\
 	ptesync;						\
 	ld	r0,0(r1);					\
-1:	cmp	cr0,r0,r0;					\
+1:	cmpd	cr0,r0,r0;					\
 	bne	1b;						\
 	IDLE_INST;						\
 	b	.