linux-kernel - [PATCH] arm32: simplify ARM_MMU

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <2200295.irdbgypaU6@devpool47.emlix.com>
Date: Mon, 07 Oct 2024 15:11:40 +0200
From: Rolf Eike Beer <eb@...ix.com>
To: Russell King <linux@...linux.org.uk>, Arnd Bergmann <arnd@...db.de>,
 Yuntao Liu <liuyuntao12@...wei.com>, Linus Walleij <linus.walleij@...aro.org>
Cc: linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH] arm32: simplify ARM_MMU_KEEP usage

All current users need to add a KEEP() around the argument so the value is
actually kept, which doesn't feel very natural and is prone to upcoming bugs as
the name suggests that this macro alone already keeps things. Move that directly
into the definition.

Signed-off-by: Rolf Eike Beer <eb@...ix.com>
---
I'm unsure if ARM_MMU_DISCARD() needs the same treatment for the non-MMU case.
I suspect noone has tried dead code elimination for non-MMU?

 arch/arm/include/asm/vmlinux.lds.h | 2 +-
 arch/arm/kernel/vmlinux-xip.lds.S  | 2 +-
 arch/arm/kernel/vmlinux.lds.S      | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/arm/include/asm/vmlinux.lds.h b/arch/arm/include/asm/vmlinux.lds.h
index d60f6e83a9f7..89697f204715 100644
--- a/arch/arm/include/asm/vmlinux.lds.h
+++ b/arch/arm/include/asm/vmlinux.lds.h
@@ -19,7 +19,7 @@
 #endif
 
 #ifdef CONFIG_MMU
-#define ARM_MMU_KEEP(x)		x
+#define ARM_MMU_KEEP(x)		KEEP(x)
 #define ARM_MMU_DISCARD(x)
 #else
 #define ARM_MMU_KEEP(x)
diff --git a/arch/arm/kernel/vmlinux-xip.lds.S b/arch/arm/kernel/vmlinux-xip.lds.S
index 5eddb75a7174..f2e8d4fac068 100644
--- a/arch/arm/kernel/vmlinux-xip.lds.S
+++ b/arch/arm/kernel/vmlinux-xip.lds.S
@@ -63,7 +63,7 @@ SECTIONS
 	. = ALIGN(4);
 	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
 		__start___ex_table = .;
-		ARM_MMU_KEEP(KEEP(*(__ex_table)))
+		ARM_MMU_KEEP(*(__ex_table))
 		__stop___ex_table = .;
 	}
 
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index de373c6c2ae8..d592a203f9c6 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -74,7 +74,7 @@ SECTIONS
 	. = ALIGN(4);
 	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
 		__start___ex_table = .;
-		ARM_MMU_KEEP(KEEP(*(__ex_table)))
+		ARM_MMU_KEEP(*(__ex_table))
 		__stop___ex_table = .;
 	}
 
-- 
2.46.1


-- 
Rolf Eike Beer

emlix GmbH
Headquarters: Berliner Str. 12, 37073 Göttingen, Germany
Phone +49 (0)551 30664-0, e-mail info@...ix.com
District Court of Göttingen, Registry Number HR B 3160
Managing Directors: Heike Jordan, Dr. Uwe Kracke
VAT ID No. DE 205 198 055
Office Berlin: Panoramastr. 1, 10178 Berlin, Germany
Office Bonn: Bachstr. 6, 53115 Bonn, Germany
http://www.emlix.com

emlix - your embedded Linux partner