[PATCH 8/8] ARM: mm: allow text and rodata sections to be read-only
From: Will Deacon <hidden>
Date: 2014-08-11 13:30:54
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On Thu, Aug 07, 2014 at 04:01:53PM +0100, Kees Cook wrote:
This introduces CONFIG_DEBUG_RODATA, making kernel text and rodata read-only. Additionally, this splits rodata from text so that rodata can also be NX, which may lead to wasted memory when aligning to SECTION_SIZE. The read-only areas are made writable during ftrace updates and kexec.
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quoted hunk ↗ jump to hunk
diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index 1ac184f2bdd8..4423a565ef6f 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c@@ -164,11 +164,11 @@ void machine_kexec(struct kimage *image) reboot_code_buffer = page_address(image->control_code_page); /* Prepare parameters for reboot_code_buffer*/ + set_kernel_text_rw(); kexec_start_address = image->start; kexec_indirection_page = page_list; kexec_mach_type = machine_arch_type; - kexec_boot_atags = dt_mem ?: image->start - - KEXEC_ARM_ZIMAGE_OFFSET + kexec_boot_atags = dt_mem ?: image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
Minor nit: but this patch and the kexec patch earlier in the series seem to move this line around in different ways without actually changing the code. I guess you just got a screwy rebase? Will