Re: [PATCH v4] riscv: fix pfn_to_virt err in do_page_fault().

From: fuyao
Date: Mon Oct 26 2020 - 22:59:58 EST


have you seen the main line?

it already corrected.

On Mon, Oct 26, 2020 at 08:46:08PM +0800, liush wrote:
> From: Shaohua Liu <liush@xxxxxxxxxxxxxxxxx>
>
> The argument to pfn_to_virt() should be pfn not the value of CSR_SATP.
>
> Reviewed-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
> Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>
> Signed-off-by: liush <liush@xxxxxxxxxxxxxxxxx>
> ---
> arch/riscv/mm/fault.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
> index 1359e21..3c8b9e4 100644
> --- a/arch/riscv/mm/fault.c
> +++ b/arch/riscv/mm/fault.c
> @@ -86,6 +86,7 @@ static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long a
> pmd_t *pmd, *pmd_k;
> pte_t *pte_k;
> int index;
> + unsigned long pfn;
>
> /* User mode accesses just cause a SIGSEGV */
> if (user_mode(regs))
> @@ -100,7 +101,8 @@ static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long a
> * of a task switch.
> */
> index = pgd_index(addr);
> - pgd = (pgd_t *)pfn_to_virt(csr_read(CSR_SATP)) + index;
> + pfn = csr_read(CSR_SATP) & SATP_PPN;
> + pgd = (pgd_t *)pfn_to_virt(pfn) + index;
> pgd_k = init_mm.pgd + index;
>
> if (!pgd_present(*pgd_k)) {
> --
> 2.7.4

--
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