On Tue, Apr 6, 2021 at 9:10 AM Jade Fink <q...@jade.fyi> wrote:
>
> Previously the qemu monitor and gdbstub looked at SUM and refused to
> perform accesses to user memory if it is off, which was an impediment to
> debugging.
>
> Signed-off-by: Jade Fink <q...@jade.fyi>
Reviewed-by: Alistair Francis <alistair.fran...@wdc.com>
Alistair
> ---
> target/riscv/cpu_helper.c | 20 ++++++++++++--------
> 1 file changed, 12 insertions(+), 8 deletions(-)
>
> diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
> index 83a6bcfad0..18ea2cba57 100644
> --- a/target/riscv/cpu_helper.c
> +++ b/target/riscv/cpu_helper.c
> @@ -299,12 +299,14 @@ void riscv_cpu_set_mode(CPURISCVState *env,
> target_ulong newpriv)
> * @first_stage: Are we in first stage translation?
> * Second stage is used for hypervisor guest translation
> * @two_stage: Are we going to perform two stage translation
> + * @is_debug: Is this access from a debugger or the monitor?
> */
> static int get_physical_address(CPURISCVState *env, hwaddr *physical,
> int *prot, target_ulong addr,
> target_ulong *fault_pte_addr,
> int access_type, int mmu_idx,
> - bool first_stage, bool two_stage)
> + bool first_stage, bool two_stage,
> + bool is_debug)
> {
> /* NOTE: the env->pc value visible here will not be
> * correct, but the value visible to the exception handler
> @@ -369,7 +371,7 @@ static int get_physical_address(CPURISCVState *env,
> hwaddr *physical,
> widened = 2;
> }
> /* status.SUM will be ignored if execute on background */
> - sum = get_field(env->mstatus, MSTATUS_SUM) || use_background;
> + sum = get_field(env->mstatus, MSTATUS_SUM) || use_background || is_debug;
> switch (vm) {
> case VM_1_10_SV32:
> levels = 2; ptidxbits = 10; ptesize = 4; break;
> @@ -428,7 +430,8 @@ restart:
> /* Do the second stage translation on the base PTE address. */
> int vbase_ret = get_physical_address(env, &vbase, &vbase_prot,
> base, NULL, MMU_DATA_LOAD,
> - mmu_idx, false, true);
> + mmu_idx, false, true,
> + is_debug);
>
> if (vbase_ret != TRANSLATE_SUCCESS) {
> if (fault_pte_addr) {
> @@ -616,13 +619,13 @@ hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs,
> vaddr addr)
> int mmu_idx = cpu_mmu_index(&cpu->env, false);
>
> if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx,
> - true, riscv_cpu_virt_enabled(env))) {
> + true, riscv_cpu_virt_enabled(env), true)) {
> return -1;
> }
>
> if (riscv_cpu_virt_enabled(env)) {
> if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL,
> - 0, mmu_idx, false, true)) {
> + 0, mmu_idx, false, true, true)) {
> return -1;
> }
> }
> @@ -714,7 +717,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int
> size,
> /* Two stage lookup */
> ret = get_physical_address(env, &pa, &prot, address,
> &env->guest_phys_fault_addr, access_type,
> - mmu_idx, true, true);
> + mmu_idx, true, true, false);
>
> /*
> * A G-stage exception may be triggered during two state lookup.
> @@ -736,7 +739,8 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int
> size,
> im_address = pa;
>
> ret = get_physical_address(env, &pa, &prot2, im_address, NULL,
> - access_type, mmu_idx, false, true);
> + access_type, mmu_idx, false, true,
> + false);
>
> qemu_log_mask(CPU_LOG_MMU,
> "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical "
> @@ -765,7 +769,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int
> size,
> } else {
> /* Single stage lookup */
> ret = get_physical_address(env, &pa, &prot, address, NULL,
> - access_type, mmu_idx, true, false);
> + access_type, mmu_idx, true, false, false);
>
> qemu_log_mask(CPU_LOG_MMU,
> "%s address=%" VADDR_PRIx " ret %d physical "
> --
> 2.31.1
>
>
