From cc0fdb298517ce56c770803447f8b02a90271152 Mon Sep 17 00:00:00 2001 From: Hesham Almatary Date: Thu, 30 May 2019 14:51:32 +0100 Subject: [PATCH] RISC-V: Check for the effective memory privilege mode during PMP checks The current PMP check function checks for env->priv which is not the effective memory privilege mode. For example, mstatus.MPRV could be set while executing in M-Mode, and in that case the privilege mode for the PMP check should be S-Mode rather than M-Mode (in env->priv) if mstatus.MPP == PRV_S. This patch passes the effective memory privilege mode to the PMP check. Functions that call the PMP check should pass the correct memory privilege mode after reading mstatus' MPRV/MPP or hstatus.SPRV (if Hypervisor mode exists). Suggested-by: Alistair Francis Signed-off-by: Hesham Almatary Reviewed-by: Palmer Dabbelt Signed-off-by: Palmer Dabbelt --- target/riscv/cpu_helper.c | 10 +++++++++- target/riscv/pmp.c | 6 +++--- target/riscv/pmp.h | 2 +- 3 files changed, 13 insertions(+), 5 deletions(-) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index ffbfaf4332..71b8123b10 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -427,19 +427,27 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, int prot; bool pmp_violation = false; int ret = TRANSLATE_FAIL; + int mode = mmu_idx; qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n", __func__, address, access_type, mmu_idx); ret = get_physical_address(env, &pa, &prot, address, access_type, mmu_idx); + if (mode == PRV_M && access_type != MMU_INST_FETCH) { + if (get_field(env->mstatus, MSTATUS_MPRV)) { + mode = get_field(env->mstatus, MSTATUS_MPP); + } + } + qemu_log_mask(CPU_LOG_MMU, "%s address=%" VADDR_PRIx " ret %d physical " TARGET_FMT_plx " prot %d\n", __func__, address, ret, pa, prot); if (riscv_feature(env, RISCV_FEATURE_PMP) && (ret == TRANSLATE_SUCCESS) && - !pmp_hart_has_privs(env, pa, TARGET_PAGE_SIZE, 1 << access_type)) { + !pmp_hart_has_privs(env, pa, TARGET_PAGE_SIZE, 1 << access_type, + mode)) { pmp_violation = true; ret = TRANSLATE_FAIL; } diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c index e0fe206407..5944f4cb66 100644 --- a/target/riscv/pmp.c +++ b/target/riscv/pmp.c @@ -228,7 +228,7 @@ static int pmp_is_in_range(CPURISCVState *env, int pmp_index, target_ulong addr) * Check if the address has required RWX privs to complete desired operation */ bool pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, - target_ulong size, pmp_priv_t privs) + target_ulong size, pmp_priv_t privs, target_ulong mode) { int i = 0; int ret = -1; @@ -264,7 +264,7 @@ bool pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, } allowed_privs = PMP_READ | PMP_WRITE | PMP_EXEC; - if ((env->priv != PRV_M) || pmp_is_locked(env, i)) { + if ((mode != PRV_M) || pmp_is_locked(env, i)) { allowed_privs &= env->pmp_state.pmp[i].cfg_reg; } @@ -280,7 +280,7 @@ bool pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, /* No rule matched */ if (ret == -1) { - if (env->priv == PRV_M) { + if (mode == PRV_M) { ret = 1; /* Privileged spec v1.10 states if no PMP entry matches an * M-Mode access, the access succeeds */ } else { diff --git a/target/riscv/pmp.h b/target/riscv/pmp.h index 66790950eb..8e19793132 100644 --- a/target/riscv/pmp.h +++ b/target/riscv/pmp.h @@ -59,6 +59,6 @@ void pmpaddr_csr_write(CPURISCVState *env, uint32_t addr_index, target_ulong val); target_ulong pmpaddr_csr_read(CPURISCVState *env, uint32_t addr_index); bool pmp_hart_has_privs(CPURISCVState *env, target_ulong addr, - target_ulong size, pmp_priv_t priv); + target_ulong size, pmp_priv_t priv, target_ulong mode); #endif