On Wed, Jan 27, 2021 at 12:12:25PM +0800, Jinyang He wrote:
> Use kimage_vaddr to indicate kernel start address. Provide kaslr_offset()
> to get the kernel offset when KASLR is enabled. Error may occur before
> update_kimage_vaddr(), so put it at the end of the offset branch.
>
> Fixes: a307a4ce9ecd ("MIPS: Loongson64: Add KASLR support")
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Signed-off-by: Jinyang He <hejinyang@xxxxxxxxxxx>
> ---
> arch/mips/include/asm/page.h | 6 ++++++
> arch/mips/kernel/relocate.c | 12 ++++++++++++
> arch/mips/kernel/setup.c | 3 +++
> 3 files changed, 21 insertions(+)
>
> diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h
> index 6a77bc4..9429520 100644
> --- a/arch/mips/include/asm/page.h
> +++ b/arch/mips/include/asm/page.h
> @@ -255,6 +255,12 @@ extern bool __virt_addr_valid(const volatile void *kaddr);
>
> #define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_TSK_EXEC
>
> +extern unsigned long kimage_vaddr;
> +static inline unsigned long kaslr_offset(void)
> +{
> + return kimage_vaddr - VMLINUX_LOAD_ADDRESS;
> +}
this breaks for 32bit kernels:
<command-line>:0:22: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
/local/tbogendoerfer/korg/linux/arch/mips/kernel/setup.c:87:41: note: in expansion of macro ‘VMLINUX_LOAD_ADDRESS’
unsigned long kimage_vaddr __initdata = VMLINUX_LOAD_ADDRESS;
^~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
--
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good idea. [ RFC1925, 2.3 ]
