On Tue, Apr 2, 2024 at 12:53 AM Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> wrote:
>
> The __do_page_fault() only check vma->flags and call handle_mm_fault(),
> and only called by do_page_fault(), let's squash it into do_page_fault()
> to cleanup code.
>
> Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Reviewed-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
> ---
> arch/arm64/mm/fault.c | 27 +++++++--------------------
> 1 file changed, 7 insertions(+), 20 deletions(-)
>
> diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
> index 8251e2fea9c7..9bb9f395351a 100644
> --- a/arch/arm64/mm/fault.c
> +++ b/arch/arm64/mm/fault.c
> @@ -486,25 +486,6 @@ static void do_bad_area(unsigned long far, unsigned long esr,
> }
> }
>
> -#define VM_FAULT_BADMAP ((__force vm_fault_t)0x010000)
> -#define VM_FAULT_BADACCESS ((__force vm_fault_t)0x020000)
> -
> -static vm_fault_t __do_page_fault(struct mm_struct *mm,
> - struct vm_area_struct *vma, unsigned long addr,
> - unsigned int mm_flags, unsigned long vm_flags,
> - struct pt_regs *regs)
> -{
> - /*
> - * Ok, we have a good vm_area for this memory access, so we can handle
> - * it.
> - * Check that the permissions on the VMA allow for the fault which
> - * occurred.
> - */
> - if (!(vma->vm_flags & vm_flags))
> - return VM_FAULT_BADACCESS;
> - return handle_mm_fault(vma, addr, mm_flags, regs);
> -}
> -
> static bool is_el0_instruction_abort(unsigned long esr)
> {
> return ESR_ELx_EC(esr) == ESR_ELx_EC_IABT_LOW;
> @@ -519,6 +500,9 @@ static bool is_write_abort(unsigned long esr)
> return (esr & ESR_ELx_WNR) && !(esr & ESR_ELx_CM);
> }
>
> +#define VM_FAULT_BADMAP ((__force vm_fault_t)0x010000)
> +#define VM_FAULT_BADACCESS ((__force vm_fault_t)0x020000)
> +
> static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
> struct pt_regs *regs)
> {
> @@ -617,7 +601,10 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr,
> goto done;
> }
>
> - fault = __do_page_fault(mm, vma, addr, mm_flags, vm_flags, regs);
> + if (!(vma->vm_flags & vm_flags))
> + fault = VM_FAULT_BADACCESS;
> + else
> + fault = handle_mm_fault(vma, addr, mm_flags, regs);
>
> /* Quick path to respond to signals */
> if (fault_signal_pending(fault, regs)) {
> --
> 2.27.0
>
