Received-SPF: pass (google.com: domain of linux-kernel+bounces-44445-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
From: Borislav Petkov <bp@alien8.de>
To: X86 ML <x86@kernel.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>,
	LKML <linux-kernel@vger.kernel.org>
Subject: [PATCH 3/4] x86/alternatives: Optimize optimize_nops()
Date: Tue, 30 Jan 2024 11:59:40 +0100
Message-ID: <20240130105941.19707-4-bp@alien8.de>
In-Reply-To: <20240130105941.19707-1-bp@alien8.de>
References: <20240130105941.19707-1-bp@alien8.de>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable

From: "Borislav Petkov (AMD)" <bp@alien8.de>

Return early if NOPs have already been optimized.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
---
 arch/x86/kernel/alternative.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.=
c
index 2dd1c7fe0949..68ee46c379c1 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -233,6 +233,10 @@ static void __init_or_module noinline optimize_nops(=
const u8 * const instr, u8 *
 		if (insn_is_nop(&insn)) {
 			int nop =3D i;
=20
+			/* Has the NOP already been optimized? */
+			if (i + insn.length =3D=3D len)
+				return;
+
 			next =3D skip_nops(buf, next, len);
=20
 			add_nop(buf + nop, next - nop);
--=20
2.43.0