linux-kernel - [tip: x86/core] x86/alternative: Drop not needed test after call of alt_replace

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Message-ID: <176043135711.709179.14364106585898871964.tip-bot2@tip-bot2>
Date: Tue, 14 Oct 2025 08:42:37 -0000
From: "tip-bot2 for Juergen Gross" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: Juergen Gross <jgross@...e.com>,
 "Peter Zijlstra (Intel)" <peterz@...radead.org>, x86@...nel.org,
 linux-kernel@...r.kernel.org
Subject: [tip: x86/core] x86/alternative: Drop not needed test after call of
 alt_replace_call()

The following commit has been merged into the x86/core branch of tip:

Commit-ID:     ad74016b919cbad78d203fa1c459ae18e73ce586
Gitweb:        https://git.kernel.org/tip/ad74016b919cbad78d203fa1c459ae18e73ce586
Author:        Juergen Gross <jgross@...e.com>
AuthorDate:    Mon, 29 Sep 2025 13:29:45 +02:00
Committer:     Peter Zijlstra <peterz@...radead.org>
CommitterDate: Tue, 14 Oct 2025 10:38:11 +02:00

x86/alternative: Drop not needed test after call of alt_replace_call()

alt_replace_call() will never return a negative value, so testing the
return value to be less than zero can be dropped.

This makes it possible to switch the return type of alt_replace_call()
and the type of insn_buff_sz to unsigned int.

Signed-off-by: Juergen Gross <jgross@...e.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
---
 arch/x86/kernel/alternative.c |  9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 8ee5ff5..4f3ea50 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -559,7 +559,7 @@ EXPORT_SYMBOL(BUG_func);
  * Rewrite the "call BUG_func" replacement to point to the target of the
  * indirect pv_ops call "call *disp(%ip)".
  */
-static int alt_replace_call(u8 *instr, u8 *insn_buff, struct alt_instr *a)
+static unsigned int alt_replace_call(u8 *instr, u8 *insn_buff, struct alt_instr *a)
 {
 	void *target, *bug = &BUG_func;
 	s32 disp;
@@ -643,7 +643,7 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start,
 	 * order.
 	 */
 	for (a = start; a < end; a++) {
-		int insn_buff_sz = 0;
+		unsigned int insn_buff_sz = 0;
 
 		/*
 		 * In case of nested ALTERNATIVE()s the outer alternative might
@@ -683,11 +683,8 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start,
 		memcpy(insn_buff, replacement, a->replacementlen);
 		insn_buff_sz = a->replacementlen;
 
-		if (a->flags & ALT_FLAG_DIRECT_CALL) {
+		if (a->flags & ALT_FLAG_DIRECT_CALL)
 			insn_buff_sz = alt_replace_call(instr, insn_buff, a);
-			if (insn_buff_sz < 0)
-				continue;
-		}
 
 		for (; insn_buff_sz < a->instrlen; insn_buff_sz++)
 			insn_buff[insn_buff_sz] = 0x90;