linux-kernel - [PATCH] ARM: fix XIP

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Message-Id: <63a630b7-9068-40f9-b7f7-d9a08f74ed13@www.fastmail.com>
Date:   Tue, 30 Aug 2022 09:20:51 +0200
From:   "Arnd Bergmann" <arnd@...db.de>
To:     "Arnd Bergmann" <arnd@...nel.org>,
        "Linus Walleij" <linus.walleij@...aro.org>
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        "Russell King" <linux@...linux.org.uk>,
        "Geert Uytterhoeven" <geert+renesas@...der.be>,
        "Krzysztof Kozlowski" <krzysztof.kozlowski@...aro.org>,
        "Ard Biesheuvel" <ardb@...nel.org>, "Sekhar Nori" <nsekhar@...com>,
        "Bartosz Golaszewski" <brgl@...ev.pl>,
        "Shawn Guo" <shawnguo@...nel.org>,
        "Sascha Hauer" <s.hauer@...gutronix.de>,
        "Pengutronix Kernel Team" <kernel@...gutronix.de>,
        "Andrew Lunn" <andrew@...n.ch>,
        "Gregory Clement" <gregory.clement@...tlin.com>,
        "Sebastian Hesselbarth" <sebastian.hesselbarth@...il.com>
Subject: [PATCH] ARM: fix XIP_KERNEL dependencies

CONFIG_XIP_KERNEL does not work with any option that involves patching
the read-only kernel .text.

Since at least CONFIG_SMP_ON_UP is required in certain configurations,
flip the dependency to always allow the .text patching options but make
XIP_KERNEL have the dependency instead.

This is a prerequisite for allowing CONFIG_ARCH_MULTIPLATFORM to
be disabled.

Signed-off-by: Arnd Bergmann <arnd@...db.de>
---
forgot to send this yesterday, replaces the CPU_v6 dependency patch

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 3066ce82cffc..2d94e53037ec 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -246,7 +246,7 @@ config ARCH_MTD_XIP
 config ARM_PATCH_PHYS_VIRT
 	bool "Patch physical to virtual translations at runtime" if EMBEDDED
 	default y
-	depends on !XIP_KERNEL && MMU
+	depends on MMU
 	help
 	  Patch phys-to-virt and virt-to-phys translation functions at
 	  boot and module load time according to the position of the
@@ -975,7 +975,7 @@ config SMP
 
 config SMP_ON_UP
 	bool "Allow booting SMP kernel on uniprocessor systems"
-	depends on SMP && !XIP_KERNEL && MMU
+	depends on SMP && MMU
 	default y
 	help
 	  SMP kernels contain instructions which fail on non-SMP processors.
@@ -1224,7 +1224,7 @@ config THUMB2_KERNEL
 
 config ARM_PATCH_IDIV
 	bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
-	depends on CPU_32v7 && !XIP_KERNEL
+	depends on CPU_32v7
 	default y
 	help
 	  The ARM compiler inserts calls to __aeabi_idiv() and
@@ -1619,6 +1619,7 @@ endchoice
 config XIP_KERNEL
 	bool "Kernel Execute-In-Place from ROM"
 	depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
+	depends on !SMP_ON_UP && !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT
 	help
 	  Execute-In-Place allows the kernel to run from non-volatile storage
 	  directly addressable by the CPU, such as NOR flash. This saves RAM