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

liush
2020-10-26T12:46:40Z

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)) {
--
2.7.4