Re: [PATCH v2 5/7] x86/mce: Change fault_in_kernel_space() from static to global

From: Borislav Petkov
Date: Mon Oct 05 2020 - 12:33:16 EST


On Wed, Sep 30, 2020 at 04:26:09PM -0700, Tony Luck wrote:
> From: Youquan Song <youquan.song@xxxxxxxxx>
>
> Machine check code needs to be able to determine if a faulting address
> is in user or kernel space. There is already a function to do this.
>
> Change from "static int" to "bool" and add declaration to <asm/traps.h>
>
> No functional change.
>
> Signed-off-by: Youquan Song <youquan.song@xxxxxxxxx>
> Signed-off-by: <tony.luck@xxxxxxxxx>
> ---
> arch/x86/include/asm/traps.h | 2 ++
> arch/x86/mm/fault.c | 2 +-
> 2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h
> index 714b1a30e7b0..df0b7bfc1234 100644
> --- a/arch/x86/include/asm/traps.h
> +++ b/arch/x86/include/asm/traps.h
> @@ -35,6 +35,8 @@ extern int panic_on_unrecovered_nmi;
>
> void math_emulate(struct math_emu_info *);
>
> +bool fault_in_kernel_space(unsigned long address);
> +
> #ifdef CONFIG_VMAP_STACK
> void __noreturn handle_stack_overflow(const char *message,
> struct pt_regs *regs,
> diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
> index 35f1498e9832..88ae443e4e5f 100644
> --- a/arch/x86/mm/fault.c
> +++ b/arch/x86/mm/fault.c
> @@ -1081,7 +1081,7 @@ access_error(unsigned long error_code, struct vm_area_struct *vma)
> return 0;
> }
>
> -static int fault_in_kernel_space(unsigned long address)
> +bool fault_in_kernel_space(unsigned long address)
> {
> /*
> * On 64-bit systems, the vsyscall page is at an address above
> --

Yeah, merge this one into the last patch where this function is used.

--
Regards/Gruss,
Boris.

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