From 9aa4ec1571da62366cfddc20f3b923609604fe63 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Wed, 9 Dec 2015 12:44:38 +0000 Subject: [PATCH] arm64: mm: fold alternatives into .init Currently we treat the alternatives separately from other data that's only used during initialisation, using separate .altinstructions and .altinstr_replacement linker sections. These are freed for general allocation separately from .init*. This is problematic as: * We do not remove execute permissions, as we do for .init, leaving the memory executable. * We pad between them, making the kernel Image bianry up to PAGE_SIZE bytes larger than necessary. This patch moves the two sections into the contiguous region used for .init*. This saves some memory, ensures that we remove execute permissions, and allows us to remove some code made redundant by this reorganisation. Signed-off-by: Mark Rutland Cc: Andre Przywara Cc: Catalin Marinas Cc: Jeremy Linton Cc: Laura Abbott Cc: Will Deacon Signed-off-by: Will Deacon --- arch/arm64/include/asm/alternative.h | 1 - arch/arm64/kernel/alternative.c | 6 ------ arch/arm64/kernel/vmlinux.lds.S | 5 ++--- arch/arm64/mm/init.c | 1 - 4 files changed, 2 insertions(+), 11 deletions(-) diff --git a/arch/arm64/include/asm/alternative.h b/arch/arm64/include/asm/alternative.h index d56ec0715157..e4962f04201e 100644 --- a/arch/arm64/include/asm/alternative.h +++ b/arch/arm64/include/asm/alternative.h @@ -19,7 +19,6 @@ struct alt_instr { void __init apply_alternatives_all(void); void apply_alternatives(void *start, size_t length); -void free_alternatives_memory(void); #define ALTINSTR_ENTRY(feature) \ " .word 661b - .\n" /* label */ \ diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index ab9db0e9818c..d2ee1b21a10d 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -158,9 +158,3 @@ void apply_alternatives(void *start, size_t length) __apply_alternatives(®ion); } - -void free_alternatives_memory(void) -{ - free_reserved_area(__alt_instructions, __alt_instructions_end, - 0, "alternatives"); -} diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index a64340df2448..f943a848f844 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -140,9 +140,6 @@ SECTIONS PERCPU_SECTION(64) - . = ALIGN(PAGE_SIZE); - __init_end = .; - . = ALIGN(4); .altinstructions : { __alt_instructions = .; @@ -154,6 +151,8 @@ SECTIONS } . = ALIGN(PAGE_SIZE); + __init_end = .; + _data = .; _sdata = .; RW_DATA_SECTION(64, PAGE_SIZE, THREAD_SIZE) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 9b8cc673f43c..2ee6c208c318 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -360,7 +360,6 @@ void free_initmem(void) { fixup_init(); free_initmem_default(0); - free_alternatives_memory(); } #ifdef CONFIG_BLK_DEV_INITRD -- 2.39.2