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| author | Qing Zhang <zhangqing@loongson.cn> | 2023-09-06 22:54:16 +0800 |
|---|---|---|
| committer | Huacai Chen <chenhuacai@loongson.cn> | 2023-09-06 22:54:16 +0800 |
| commit | 9fbcc076798ead2af28c854a265d9da83bec8429 (patch) | |
| tree | e6a28a961e50a2a2219f101b1c9cf62310cdcbe1 | |
| parent | fb6d5c1d99ab6958c5e284f7aa5f0cc553f0268c (diff) | |
| download | linux-aarch64-9fbcc076798ead2af28c854a265d9da83bec8429.tar.gz | |
LoongArch: Simplify the processing of jumping new kernel for KASLR
Modified relocate_kernel() doesn't return new kernel's entry point but
the random_offset. In this way we share the start_kernel() processing
with the normal kernel, which avoids calling 'jr a0' directly and allows
some other operations (e.g, kasan_early_init) before start_kernel() when
KASLR (CONFIG_RANDOMIZE_BASE) is turned on.
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
| -rw-r--r-- | arch/loongarch/include/asm/setup.h | 2 | ||||
| -rw-r--r-- | arch/loongarch/kernel/head.S | 11 | ||||
| -rw-r--r-- | arch/loongarch/kernel/relocate.c | 8 |
3 files changed, 9 insertions, 12 deletions
diff --git a/arch/loongarch/include/asm/setup.h b/arch/loongarch/include/asm/setup.h index 7c68b4365a4def..a0bc159ce8bdc0 100644 --- a/arch/loongarch/include/asm/setup.h +++ b/arch/loongarch/include/asm/setup.h @@ -34,7 +34,7 @@ extern long __la_abs_end; extern long __rela_dyn_begin; extern long __rela_dyn_end; -extern void * __init relocate_kernel(void); +extern unsigned long __init relocate_kernel(void); #endif diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S index 5e828a8bc0a0e0..5743fef70dfefa 100644 --- a/arch/loongarch/kernel/head.S +++ b/arch/loongarch/kernel/head.S @@ -95,13 +95,14 @@ SYM_CODE_START(kernel_entry) # kernel entry point PTR_LI sp, (_THREAD_SIZE - PT_SIZE) PTR_ADD sp, sp, tp set_saved_sp sp, t0, t1 -#endif - /* relocate_kernel() returns the new kernel entry point */ - jr a0 - ASM_BUG() + /* Jump to the new kernel: new_pc = current_pc + random_offset */ + pcaddi t0, 0 + add.d t0, t0, a0 + jirl zero, t0, 0xc +#endif /* CONFIG_RANDOMIZE_BASE */ -#endif +#endif /* CONFIG_RELOCATABLE */ bl start_kernel ASM_BUG() diff --git a/arch/loongarch/kernel/relocate.c b/arch/loongarch/kernel/relocate.c index 01f94d1e3edf6f..6c3eff9af9fb1e 100644 --- a/arch/loongarch/kernel/relocate.c +++ b/arch/loongarch/kernel/relocate.c @@ -157,12 +157,11 @@ static inline void __init update_reloc_offset(unsigned long *addr, long random_o *new_addr = (unsigned long)reloc_offset; } -void * __init relocate_kernel(void) +unsigned long __init relocate_kernel(void) { unsigned long kernel_length; unsigned long random_offset = 0; void *location_new = _text; /* Default to original kernel start */ - void *kernel_entry = start_kernel; /* Default to original kernel entry point */ char *cmdline = early_ioremap(fw_arg1, COMMAND_LINE_SIZE); /* Boot command line is passed in fw_arg1 */ strscpy(boot_command_line, cmdline, COMMAND_LINE_SIZE); @@ -190,9 +189,6 @@ void * __init relocate_kernel(void) reloc_offset += random_offset; - /* Return the new kernel's entry point */ - kernel_entry = RELOCATED_KASLR(start_kernel); - /* The current thread is now within the relocated kernel */ __current_thread_info = RELOCATED_KASLR(__current_thread_info); @@ -204,7 +200,7 @@ void * __init relocate_kernel(void) relocate_absolute(random_offset); - return kernel_entry; + return random_offset; } /* |