From: Heiko Carstens <hca@linux.ibm.com>
Date: Sun, 13 Mar 2022 21:04:10 +0000 (+0100)
Subject: s390/alternatives: use instructions instead of byte patterns
X-Git-Tag: v6.1-rc5~1640^2~18
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4afeb670710efa5cd5ed8b1d9f2d22d6ce332bcc;p=platform%2Fkernel%2Flinux-starfive.git

s390/alternatives: use instructions instead of byte patterns

Use readable nop instructions within the code which generates
the padding areas, instead of unreadable byte patterns.

The generated code is identical.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
---

diff --git a/arch/s390/include/asm/alternative-asm.h b/arch/s390/include/asm/alternative-asm.h
index 955d620..221d790 100644
--- a/arch/s390/include/asm/alternative-asm.h
+++ b/arch/s390/include/asm/alternative-asm.h
@@ -37,9 +37,15 @@
  * a 2-byte nop if the size of the area is not divisible by 6.
  */
 .macro alt_pad_fill bytes
-	.fill	( \bytes ) / 6, 6, 0xc0040000
-	.fill	( \bytes ) % 6 / 4, 4, 0x47000000
-	.fill	( \bytes ) % 6 % 4 / 2, 2, 0x0700
+	.rept	( \bytes ) / 6
+	jgnop	.
+	.endr
+	.rept	( \bytes ) % 6 / 4
+	nop
+	.endr
+	.rept	( \bytes ) % 6 % 4 / 2
+	nopr
+	.endr
 .endm
 
 /*
diff --git a/arch/s390/include/asm/alternative.h b/arch/s390/include/asm/alternative.h
index d3880ca..6c72495 100644
--- a/arch/s390/include/asm/alternative.h
+++ b/arch/s390/include/asm/alternative.h
@@ -71,11 +71,18 @@ void apply_alternatives(struct alt_instr *start, struct alt_instr *end);
 	".if " oldinstr_pad_len(num) " > 6\n"				\
 	"\tjg " e_oldinstr_pad_end "f\n"				\
 	"6620:\n"							\
-	"\t.fill (" oldinstr_pad_len(num) " - (6620b-662b)) / 2, 2, 0x0700\n" \
+	"\t.rept (" oldinstr_pad_len(num) " - (6620b-662b)) / 2\n"	\
+	"\tnopr\n"							\
 	".else\n"							\
-	"\t.fill " oldinstr_pad_len(num) " / 6, 6, 0xc0040000\n"	\
-	"\t.fill " oldinstr_pad_len(num) " %% 6 / 4, 4, 0x47000000\n"	\
-	"\t.fill " oldinstr_pad_len(num) " %% 6 %% 4 / 2, 2, 0x0700\n"	\
+	"\t.rept " oldinstr_pad_len(num) " / 6\n"			\
+	"\t.jgnop .\n"							\
+	"\t.endr\n"							\
+	"\t.rept " oldinstr_pad_len(num) " %% 6 / 4\n"			\
+	"\tnop\n"							\
+	"\t.endr\n"							\
+	"\t.rept " oldinstr_pad_len(num) " %% 6 %% 4 / 2\n"		\
+	"\tnopr\n"							\
+	".endr\n"							\
 	".endif\n"
 
 #define OLDINSTR(oldinstr, num)						\