5.15-stable review patch. If anyone has any objections, please let me know.
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From: Harith G harith.g@alifsemi.com
[ Upstream commit ed6cbe6e5563452f305e89c15846820f2874e431 ]
The patchset introducing kernel_sec_start/end variables to separate the kernel/lowmem memory mappings, broke the mapping of the kernel memory for xipkernels.
kernel_sec_start/end variables are in RO area before the MMU is switched on for xipkernels. So these cannot be set early in boot in head.S. Fix this by setting these after MMU is switched on. xipkernels need two different mappings for kernel text (starting at CONFIG_XIP_PHYS_ADDR) and data (starting at CONFIG_PHYS_OFFSET). Also, move the kernel code mapping from devicemaps_init() to map_kernel().
Fixes: a91da5457085 ("ARM: 9089/1: Define kernel physical section start and end") Signed-off-by: Harith George harith.g@alifsemi.com Reviewed-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Russell King (Oracle) rmk+kernel@armlinux.org.uk Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/kernel/head.S | 8 ++++++-- arch/arm/mm/mmu.c | 34 +++++++++++++++++++++------------- 2 files changed, 27 insertions(+), 15 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 3fc7f9750ce4b..0638d20061d8c 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -252,11 +252,15 @@ __create_page_tables: */ add r0, r4, #KERNEL_OFFSET >> (SECTION_SHIFT - PMD_ORDER) ldr r6, =(_end - 1) + + /* For XIP, kernel_sec_start/kernel_sec_end are currently in RO memory */ +#ifndef CONFIG_XIP_KERNEL adr_l r5, kernel_sec_start @ _pa(kernel_sec_start) #if defined CONFIG_CPU_ENDIAN_BE8 || defined CONFIG_CPU_ENDIAN_BE32 str r8, [r5, #4] @ Save physical start of kernel (BE) #else str r8, [r5] @ Save physical start of kernel (LE) +#endif #endif orr r3, r8, r7 @ Add the MMU flags add r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER) @@ -264,6 +268,7 @@ __create_page_tables: add r3, r3, #1 << SECTION_SHIFT cmp r0, r6 bls 1b +#ifndef CONFIG_XIP_KERNEL eor r3, r3, r7 @ Remove the MMU flags adr_l r5, kernel_sec_end @ _pa(kernel_sec_end) #if defined CONFIG_CPU_ENDIAN_BE8 || defined CONFIG_CPU_ENDIAN_BE32 @@ -271,8 +276,7 @@ __create_page_tables: #else str r3, [r5] @ Save physical end of kernel (LE) #endif - -#ifdef CONFIG_XIP_KERNEL +#else /* * Map the kernel image separately as it is not located in RAM. */ diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 83a91e0ab8480..fc0ef1c913c1b 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -1381,18 +1381,6 @@ static void __init devicemaps_init(const struct machine_desc *mdesc) create_mapping(&map); }
- /* - * Map the kernel if it is XIP. - * It is always first in the modulearea. - */ -#ifdef CONFIG_XIP_KERNEL - map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK); - map.virtual = MODULES_VADDR; - map.length = ((unsigned long)_exiprom - map.virtual + ~SECTION_MASK) & SECTION_MASK; - map.type = MT_ROM; - create_mapping(&map); -#endif - /* * Map the cache flushing regions. */ @@ -1582,12 +1570,27 @@ static void __init map_kernel(void) * This will only persist until we turn on proper memory management later on * and we remap the whole kernel with page granularity. */ +#ifdef CONFIG_XIP_KERNEL + phys_addr_t kernel_nx_start = kernel_sec_start; +#else phys_addr_t kernel_x_start = kernel_sec_start; phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE); phys_addr_t kernel_nx_start = kernel_x_end; +#endif phys_addr_t kernel_nx_end = kernel_sec_end; struct map_desc map;
+ /* + * Map the kernel if it is XIP. + * It is always first in the modulearea. + */ +#ifdef CONFIG_XIP_KERNEL + map.pfn = __phys_to_pfn(CONFIG_XIP_PHYS_ADDR & SECTION_MASK); + map.virtual = MODULES_VADDR; + map.length = ((unsigned long)_exiprom - map.virtual + ~SECTION_MASK) & SECTION_MASK; + map.type = MT_ROM; + create_mapping(&map); +#else map.pfn = __phys_to_pfn(kernel_x_start); map.virtual = __phys_to_virt(kernel_x_start); map.length = kernel_x_end - kernel_x_start; @@ -1597,7 +1600,7 @@ static void __init map_kernel(void) /* If the nx part is small it may end up covered by the tail of the RWX section */ if (kernel_x_end == kernel_nx_end) return; - +#endif map.pfn = __phys_to_pfn(kernel_nx_start); map.virtual = __phys_to_virt(kernel_nx_start); map.length = kernel_nx_end - kernel_nx_start; @@ -1742,6 +1745,11 @@ void __init paging_init(const struct machine_desc *mdesc) { void *zero_page;
+#ifdef CONFIG_XIP_KERNEL + /* Store the kernel RW RAM region start/end in these variables */ + kernel_sec_start = CONFIG_PHYS_OFFSET & SECTION_MASK; + kernel_sec_end = round_up(__pa(_end), SECTION_SIZE); +#endif pr_debug("physical kernel sections: 0x%08llx-0x%08llx\n", kernel_sec_start, kernel_sec_end);