On 9/18/19 1:22 AM, Alistair Francis wrote:
> From: Palmer Dabbelt <pal...@sifive.com>
>
> We directly access physical memory while walking the page tables on
> RISC-V, but while doing so we were using cpu_ld*() which does not report
> bus errors. This patch converts the page table walker over to use
> address_space_ld*(), which allows bus errors to be detected.
>
> Signed-off-by: Palmer Dabbelt <pal...@sifive.com>
> Signed-off-by: Alistair Francis <alistair.fran...@wdc.com>
> ---
> target/riscv/cpu_helper.c | 12 +++++++++---
> 1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
> index 87dd6a6ece..c82e7ed52b 100644
> --- a/target/riscv/cpu_helper.c
> +++ b/target/riscv/cpu_helper.c
> @@ -169,7 +169,8 @@ static int get_physical_address(CPURISCVState *env,
> hwaddr *physical,
> /* NOTE: the env->pc value visible here will not be
> * correct, but the value visible to the exception handler
> * (riscv_cpu_do_interrupt) is correct */
> -
> + MemTxResult res;
> + MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
> int mode = mmu_idx;
>
> if (mode == PRV_M && access_type != MMU_INST_FETCH) {
> @@ -256,11 +257,16 @@ restart:
> 1 << MMU_DATA_LOAD, PRV_S)) {
> return TRANSLATE_PMP_FAIL;
> }
> +
> #if defined(TARGET_RISCV32)
> - target_ulong pte = ldl_phys(cs->as, pte_addr);
> + target_ulong pte = address_space_ldl(cs->as, pte_addr, attrs, &res);
> #elif defined(TARGET_RISCV64)
> - target_ulong pte = ldq_phys(cs->as, pte_addr);
> + target_ulong pte = address_space_ldq(cs->as, pte_addr, attrs, &res);
> #endif
> + if (res != MEMTX_OK) {
> + return TRANSLATE_FAIL;
> + }
> +
> hwaddr ppn = pte >> PTE_PPN_SHIFT;
>
> if (!(pte & PTE_V)) {
>
Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>
