summaryrefslogtreecommitdiff
path: root/arch/loongarch/kernel/relocate.c
AgeCommit message (Collapse)Author
2023-02-25LoongArch: Add support for kernel address space layout randomization (KASLR)Youling Tang
This patch adds support for relocating the kernel to a random address. Entropy is derived from the banner, which will change every build and random_get_entropy() which should provide additional runtime entropy. The kernel is relocated by up to RANDOMIZE_BASE_MAX_OFFSET bytes from its link address. Because relocation happens so early during the kernel booting, the amount of physical memory has not yet been determined. This means the only way to limit relocation within the available memory is via Kconfig. So we limit the maximum value of RANDOMIZE_BASE_MAX_OFFSET to 256M (0x10000000) because our memory layout has many holes. Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Xi Ruoyao <xry111@xry111.site> # Fix compiler warnings Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25LoongArch: Add support for kernel relocationYouling Tang
This config allows to compile kernel as PIE and to relocate it at any virtual address at runtime: this paves the way to KASLR. Runtime relocation is possible since relocation metadata are embedded into the kernel. Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Xi Ruoyao <xry111@xry111.site> # Use arch_initcall Signed-off-by: Jinyang He <hejinyang@loongson.cn> # Provide la_abs relocation code Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>