diff options
Diffstat (limited to 'target/arm/helper.c')
| -rw-r--r-- | target/arm/helper.c | 78 |
1 files changed, 55 insertions, 23 deletions
diff --git a/target/arm/helper.c b/target/arm/helper.c index a7edeb6663..3c6a4c565b 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -41,6 +41,7 @@ static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address, /* Security attributes for an address, as returned by v8m_security_lookup. */ typedef struct V8M_SAttributes { + bool subpage; /* true if these attrs don't cover the whole TARGET_PAGE */ bool ns; bool nsc; uint8_t sregion; @@ -9804,6 +9805,8 @@ static void v8m_security_lookup(CPUARMState *env, uint32_t address, int r; bool idau_exempt = false, idau_ns = true, idau_nsc = true; int idau_region = IREGION_NOTVALID; + uint32_t addr_page_base = address & TARGET_PAGE_MASK; + uint32_t addr_page_limit = addr_page_base + (TARGET_PAGE_SIZE - 1); if (cpu->idau) { IDAUInterfaceClass *iic = IDAU_INTERFACE_GET_CLASS(cpu->idau); @@ -9841,6 +9844,9 @@ static void v8m_security_lookup(CPUARMState *env, uint32_t address, uint32_t limit = env->sau.rlar[r] | 0x1f; if (base <= address && limit >= address) { + if (base > addr_page_base || limit < addr_page_limit) { + sattrs->subpage = true; + } if (sattrs->srvalid) { /* If we hit in more than one region then we must report * as Secure, not NS-Callable, with no valid region @@ -9880,13 +9886,16 @@ static void v8m_security_lookup(CPUARMState *env, uint32_t address, static bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address, MMUAccessType access_type, ARMMMUIdx mmu_idx, hwaddr *phys_ptr, MemTxAttrs *txattrs, - int *prot, ARMMMUFaultInfo *fi, uint32_t *mregion) + int *prot, bool *is_subpage, + ARMMMUFaultInfo *fi, uint32_t *mregion) { /* Perform a PMSAv8 MPU lookup (without also doing the SAU check * that a full phys-to-virt translation does). * mregion is (if not NULL) set to the region number which matched, * or -1 if no region number is returned (MPU off, address did not * hit a region, address hit in multiple regions). + * We set is_subpage to true if the region hit doesn't cover the + * entire TARGET_PAGE the address is within. */ ARMCPU *cpu = arm_env_get_cpu(env); bool is_user = regime_is_user(env, mmu_idx); @@ -9894,7 +9903,10 @@ static bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address, int n; int matchregion = -1; bool hit = false; + uint32_t addr_page_base = address & TARGET_PAGE_MASK; + uint32_t addr_page_limit = addr_page_base + (TARGET_PAGE_SIZE - 1); + *is_subpage = false; *phys_ptr = address; *prot = 0; if (mregion) { @@ -9932,6 +9944,10 @@ static bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address, continue; } + if (base > addr_page_base || limit < addr_page_limit) { + *is_subpage = true; + } + if (hit) { /* Multiple regions match -- always a failure (unlike * PMSAv7 where highest-numbered-region wins) @@ -9943,23 +9959,6 @@ static bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address, matchregion = n; hit = true; - - if (base & ~TARGET_PAGE_MASK) { - qemu_log_mask(LOG_UNIMP, - "MPU_RBAR[%d]: No support for MPU region base" - "address of 0x%" PRIx32 ". Minimum alignment is " - "%d\n", - n, base, TARGET_PAGE_BITS); - continue; - } - if ((limit + 1) & ~TARGET_PAGE_MASK) { - qemu_log_mask(LOG_UNIMP, - "MPU_RBAR[%d]: No support for MPU region limit" - "address of 0x%" PRIx32 ". Minimum alignment is " - "%d\n", - n, limit, TARGET_PAGE_BITS); - continue; - } } } @@ -9995,6 +9994,18 @@ static bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address, fi->type = ARMFault_Permission; fi->level = 1; + /* + * Core QEMU code can't handle execution from small pages yet, so + * don't try it. This means any attempted execution will generate + * an MPU exception, rather than eventually causing QEMU to exit in + * get_page_addr_code(). + */ + if (*is_subpage && (*prot & PAGE_EXEC)) { + qemu_log_mask(LOG_UNIMP, + "MPU: No support for execution from regions " + "smaller than 1K\n"); + *prot &= ~PAGE_EXEC; + } return !(*prot & (1 << access_type)); } @@ -10002,10 +10013,13 @@ static bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address, static bool get_phys_addr_pmsav8(CPUARMState *env, uint32_t address, MMUAccessType access_type, ARMMMUIdx mmu_idx, hwaddr *phys_ptr, MemTxAttrs *txattrs, - int *prot, ARMMMUFaultInfo *fi) + int *prot, target_ulong *page_size, + ARMMMUFaultInfo *fi) { uint32_t secure = regime_is_secure(env, mmu_idx); V8M_SAttributes sattrs = {}; + bool ret; + bool mpu_is_subpage; if (arm_feature(env, ARM_FEATURE_M_SECURITY)) { v8m_security_lookup(env, address, access_type, mmu_idx, &sattrs); @@ -10033,6 +10047,7 @@ static bool get_phys_addr_pmsav8(CPUARMState *env, uint32_t address, } else { fi->type = ARMFault_QEMU_SFault; } + *page_size = sattrs.subpage ? 1 : TARGET_PAGE_SIZE; *phys_ptr = address; *prot = 0; return true; @@ -10055,6 +10070,7 @@ static bool get_phys_addr_pmsav8(CPUARMState *env, uint32_t address, * for M_FAKE_FSR_SFAULT in arm_v7m_cpu_do_interrupt(). */ fi->type = ARMFault_QEMU_SFault; + *page_size = sattrs.subpage ? 1 : TARGET_PAGE_SIZE; *phys_ptr = address; *prot = 0; return true; @@ -10062,8 +10078,22 @@ static bool get_phys_addr_pmsav8(CPUARMState *env, uint32_t address, } } - return pmsav8_mpu_lookup(env, address, access_type, mmu_idx, phys_ptr, - txattrs, prot, fi, NULL); + ret = pmsav8_mpu_lookup(env, address, access_type, mmu_idx, phys_ptr, + txattrs, prot, &mpu_is_subpage, fi, NULL); + /* + * TODO: this is a temporary hack to ignore the fact that the SAU region + * is smaller than a page if this is an executable region. We never + * supported small MPU regions, but we did (accidentally) allow small + * SAU regions, and if we now made small SAU regions not be executable + * then this would break previously working guest code. We can't + * remove this until/unless we implement support for execution from + * small regions. + */ + if (*prot & PAGE_EXEC) { + sattrs.subpage = false; + } + *page_size = sattrs.subpage || mpu_is_subpage ? 1 : TARGET_PAGE_SIZE; + return ret; } static bool get_phys_addr_pmsav5(CPUARMState *env, uint32_t address, @@ -10339,7 +10369,7 @@ static bool get_phys_addr(CPUARMState *env, target_ulong address, if (arm_feature(env, ARM_FEATURE_V8)) { /* PMSAv8 */ ret = get_phys_addr_pmsav8(env, address, access_type, mmu_idx, - phys_ptr, attrs, prot, fi); + phys_ptr, attrs, prot, page_size, fi); } else if (arm_feature(env, ARM_FEATURE_V7)) { /* PMSAv7 */ ret = get_phys_addr_pmsav7(env, address, access_type, mmu_idx, @@ -10757,6 +10787,7 @@ uint32_t HELPER(v7m_tt)(CPUARMState *env, uint32_t addr, uint32_t op) uint32_t mregion; bool targetpriv; bool targetsec = env->v7m.secure; + bool is_subpage; /* Work out what the security state and privilege level we're * interested in is... @@ -10786,7 +10817,8 @@ uint32_t HELPER(v7m_tt)(CPUARMState *env, uint32_t addr, uint32_t op) if (arm_current_el(env) != 0 || alt) { /* We can ignore the return value as prot is always set */ pmsav8_mpu_lookup(env, addr, MMU_DATA_LOAD, mmu_idx, - &phys_addr, &attrs, &prot, &fi, &mregion); + &phys_addr, &attrs, &prot, &is_subpage, + &fi, &mregion); if (mregion == -1) { mrvalid = false; mregion = 0; |