From 02afa9a87b232bca15bc30808b9310c6388ca1a8 Mon Sep 17 00:00:00 2001 From: Chris Brandt Date: Tue, 9 Feb 2016 19:34:43 +0100 Subject: [PATCH] ARM: 8518/1: Use correct symbols for XIP_KERNEL For an XIP build, _etext does not represent the end of the binary image that needs to stay mapped into the MODULES_VADDR area. Years ago, data came before text in the memory map. However, now that the order is text/init/data, an XIP_KERNEL needs to map up to the data location in order to keep from cutting off parts of the kernel that are needed. We only map up to the beginning of data because data has already been copied, so there's no reason to keep it around anymore. A new symbol is created to make it clear what it is we are referring to. This fixes the bug where you might lose the end of your kernel area after page table setup is complete. Signed-off-by: Chris Brandt Signed-off-by: Russell King --- arch/arm/include/asm/Kbuild | 1 - arch/arm/include/asm/sections.h | 8 ++++++++ arch/arm/kernel/module.c | 2 +- arch/arm/kernel/vmlinux-xip.lds.S | 2 ++ arch/arm/mm/mmu.c | 8 ++++++-- 5 files changed, 17 insertions(+), 4 deletions(-) create mode 100644 arch/arm/include/asm/sections.h diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index 16da6380eb85..3f6616b472af 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -23,7 +23,6 @@ generic-y += preempt.h generic-y += resource.h generic-y += rwsem.h generic-y += seccomp.h -generic-y += sections.h generic-y += segment.h generic-y += sembuf.h generic-y += serial.h diff --git a/arch/arm/include/asm/sections.h b/arch/arm/include/asm/sections.h new file mode 100644 index 000000000000..803bbf2b20b8 --- /dev/null +++ b/arch/arm/include/asm/sections.h @@ -0,0 +1,8 @@ +#ifndef _ASM_ARM_SECTIONS_H +#define _ASM_ARM_SECTIONS_H + +#include + +extern char _exiprom[]; + +#endif /* _ASM_ARM_SECTIONS_H */ diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c index efdddcb97dd1..4f14b5ce6535 100644 --- a/arch/arm/kernel/module.c +++ b/arch/arm/kernel/module.c @@ -34,7 +34,7 @@ * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off. */ #undef MODULES_VADDR -#define MODULES_VADDR (((unsigned long)_etext + ~PMD_MASK) & PMD_MASK) +#define MODULES_VADDR (((unsigned long)_exiprom + ~PMD_MASK) & PMD_MASK) #endif #ifdef CONFIG_MMU diff --git a/arch/arm/kernel/vmlinux-xip.lds.S b/arch/arm/kernel/vmlinux-xip.lds.S index 7b1ded6fb628..40bc4cadb959 100644 --- a/arch/arm/kernel/vmlinux-xip.lds.S +++ b/arch/arm/kernel/vmlinux-xip.lds.S @@ -85,6 +85,7 @@ SECTIONS } . = XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR); + _xiprom = .; /* XIP ROM area to be mapped */ .head.text : { _text = .; @@ -210,6 +211,7 @@ SECTIONS PERCPU_SECTION(L1_CACHE_BYTES) #endif + _exiprom = .; /* End of XIP ROM area */ __data_loc = ALIGN(4); /* location in binary */ . = PAGE_OFFSET + TEXT_OFFSET; diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 434d76f0b363..e4b681aafd6d 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -1253,7 +1253,7 @@ static inline void prepare_page_table(void) #ifdef CONFIG_XIP_KERNEL /* The XIP kernel is mapped in the module area -- skip over it */ - addr = ((unsigned long)_etext + PMD_SIZE - 1) & PMD_MASK; + addr = ((unsigned long)_exiprom + PMD_SIZE - 1) & PMD_MASK; #endif for ( ; addr < PAGE_OFFSET; addr += PMD_SIZE) pmd_clear(pmd_off_k(addr)); @@ -1335,7 +1335,7 @@ static void __init devicemaps_init(const struct machine_desc *mdesc) #ifdef CONFIG_XIP_KERNEL map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK); map.virtual = MODULES_VADDR; - map.length = ((unsigned long)_etext - map.virtual + ~SECTION_MASK) & SECTION_MASK; + map.length = ((unsigned long)_exiprom - map.virtual + ~SECTION_MASK) & SECTION_MASK; map.type = MT_ROM; create_mapping(&map); #endif @@ -1426,7 +1426,11 @@ static void __init kmap_init(void) static void __init map_lowmem(void) { struct memblock_region *reg; +#ifdef CONFIG_XIP_KERNEL + phys_addr_t kernel_x_start = round_down(__pa(_sdata), SECTION_SIZE); +#else phys_addr_t kernel_x_start = round_down(__pa(_stext), SECTION_SIZE); +#endif phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE); /* Map all the lowmem memory banks. */ -- 2.20.1