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

fuyao
2020-10-28T02:32:17Z

Shaohua:
sorry, i read it wrong. this patch is right.

On Tue, Oct 27, 2020 at 10:59:52AM +0800, fuyao wrote:
> 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@allwinnertech.com>
> >
> > The argument to pfn_to_virt() should be pfn not the value of CSR_SATP.
> >
> > Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
> > Reviewed-by: Anup Patel <anup@brainfault.org>
> > Signed-off-by: liush <liush@allwinnertech.com>
> > ---
> > 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)) {