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| author | Youling Tang <tangyouling@loongson.cn> | 2023-02-25 15:52:56 +0800 |
|---|---|---|
| committer | Huacai Chen <chenhuacai@loongson.cn> | 2023-02-25 22:12:16 +0800 |
| commit | d8da19fbdedd5852592fbba18a7348e3f09500e6 (patch) | |
| tree | a6a4a921da97d0b7379e9034532c8267a14b631e /arch/loongarch/include | |
| parent | 396233c650084cb957eb6d87dd4abd3e56a7d499 (diff) | |
| download | lwn-d8da19fbdedd5852592fbba18a7348e3f09500e6.tar.gz lwn-d8da19fbdedd5852592fbba18a7348e3f09500e6.zip | |
LoongArch: Add support for kernel relocation
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>
Diffstat (limited to 'arch/loongarch/include')
| -rw-r--r-- | arch/loongarch/include/asm/asmmacro.h | 13 | ||||
| -rw-r--r-- | arch/loongarch/include/asm/setup.h | 16 |
2 files changed, 29 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/asmmacro.h b/arch/loongarch/include/asm/asmmacro.h index cdc9935d5554..c51a1b43acb4 100644 --- a/arch/loongarch/include/asm/asmmacro.h +++ b/arch/loongarch/include/asm/asmmacro.h @@ -275,7 +275,20 @@ .endm .macro la_abs reg, sym +#ifndef CONFIG_RELOCATABLE la.abs \reg, \sym +#else + 766: + lu12i.w \reg, 0 + ori \reg, \reg, 0 + lu32i.d \reg, 0 + lu52i.d \reg, \reg, 0 + .pushsection ".la_abs", "aw", %progbits + 768: + .dword 768b-766b + .dword \sym + .popsection +#endif .endm #endif /* _ASM_ASMMACRO_H */ diff --git a/arch/loongarch/include/asm/setup.h b/arch/loongarch/include/asm/setup.h index 72ead58039f3..27d968655b4b 100644 --- a/arch/loongarch/include/asm/setup.h +++ b/arch/loongarch/include/asm/setup.h @@ -21,4 +21,20 @@ extern void per_cpu_trap_init(int cpu); extern void set_handler(unsigned long offset, void *addr, unsigned long len); extern void set_merr_handler(unsigned long offset, void *addr, unsigned long len); +#ifdef CONFIG_RELOCATABLE + +struct rela_la_abs { + long offset; + long symvalue; +}; + +extern long __la_abs_begin; +extern long __la_abs_end; +extern long __rela_dyn_begin; +extern long __rela_dyn_end; + +extern void __init relocate_kernel(void); + +#endif + #endif /* __SETUP_H */ |