Re: [PATCH v2 2/2] MIPS: relocatable: Use __kaslr_offset in show_kernel_relocation
From: Thomas Bogendoerfer
Date: Thu Feb 04 2021 - 10:48:08 EST
On Wed, Feb 03, 2021 at 06:35:10PM +0800, Jinyang He wrote:
> The type of the VMLINUX_LOAD_ADDRESS macro is the (unsigned long long)
> in 32bits kernel but (unsigned long) in the 64-bit kernel. Although there
> is no error here, avoid using it to calculate kaslr_offset. And here we
> may need is that the address of __kaslr_offset rather than (void *)offset.
>
> Signed-off-by: Jinyang He <hejinyang@xxxxxxxxxxx>
> ---
> arch/mips/kernel/relocate.c | 8 ++------
> 1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c
> index 95abb9c..52018a3 100644
> --- a/arch/mips/kernel/relocate.c
> +++ b/arch/mips/kernel/relocate.c
> @@ -430,13 +430,9 @@ void *__init relocate_kernel(void)
> */
> static void show_kernel_relocation(const char *level)
> {
> - unsigned long offset;
> -
> - offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
> -
> - if (IS_ENABLED(CONFIG_RELOCATABLE) && offset > 0) {
> + if (__kaslr_offset > 0) {
> printk(level);
> - pr_cont("Kernel relocated by 0x%pK\n", (void *)offset);
> + pr_cont("Kernel relocated by 0x%pK\n", &__kaslr_offset);
are you sure ? I would have expected (void *)__kaslr_offset here.
Thomas.
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