[PATCH v2 12/17] linux-user/aarch64: Pass syndrome to EXC_*_ABORT

[Richard Henderson]

A proper syndrome is required to fill in the proper si_code.
Use page_get_flags to determine permission vs translation
for user-only.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/aarch64/cpu_loop.c | 23 ++++++++++++++++++++---
 target/arm/tlb_helper.c       | 27 +++++++++++++++++++++------
 2 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/linux-user/aarch64/cpu_loop.c b/linux-user/aarch64/cpu_loop.c
index 3cca637bb9..ce56e15be2 100644
--- a/linux-user/aarch64/cpu_loop.c
+++ b/linux-user/aarch64/cpu_loop.c
@@ -75,7 +75,7 @@
 void cpu_loop(CPUARMState *env)
 {
     CPUState *cs = env_cpu(env);
-    int trapnr;
+    int trapnr, ec, fsc;
     abi_long ret;
     target_siginfo_t info;
 
@@ -116,9 +116,26 @@ void cpu_loop(CPUARMState *env)
         case EXCP_DATA_ABORT:
             info.si_signo = TARGET_SIGSEGV;
             info.si_errno = 0;
-            /* XXX: check env->error_code */
-            info.si_code = TARGET_SEGV_MAPERR;
             info._sifields._sigfault._addr = env->exception.vaddress;
+
+            /* We should only arrive here with EC in {DATAABORT, INSNABORT}. */
+            ec = extract32(env->exception.syndrome, 26, 6);
+            assert(ec == 0x24 || ec == 0x20);
+
+            /* Both EC have the same format for FSC, or close enough. */
+            fsc = extract32(env->exception.syndrome, 0, 6);
+            switch (fsc) {
+            case 0x04 ... 0x07: /* Translation fault, level {0-3} */
+                info.si_code = TARGET_SEGV_MAPERR;
+                break;
+            case 0x09 ... 0x0b: /* Access flag fault, level {1-3} */
+            case 0x0d ... 0x0f: /* Permission fault, level {1-3} */
+                info.si_code = TARGET_SEGV_ACCERR;
+                break;
+            default:
+                g_assert_not_reached();
+            }
+
             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
             break;
         case EXCP_UNALIGNED:
diff --git a/target/arm/tlb_helper.c b/target/arm/tlb_helper.c
index d4e6d37f4f..35d84ac24f 100644
--- a/target/arm/tlb_helper.c
+++ b/target/arm/tlb_helper.c
@@ -10,8 +10,6 @@
 #include "internals.h"
 #include "exec/exec-all.h"
 
-#if !defined(CONFIG_USER_ONLY)
-
 static inline uint32_t merge_syn_data_abort(uint32_t template_syn,
                                             unsigned int target_el,
                                             bool same_el, bool ea,
@@ -51,6 +49,8 @@ static inline uint32_t merge_syn_data_abort(uint32_t 
template_syn,
     return syn;
 }
 
+#if !defined(CONFIG_USER_ONLY)
+
 static void QEMU_NORETURN arm_deliver_fault(ARMCPU *cpu, vaddr addr,
                                             MMUAccessType access_type,
                                             int mmu_idx, ARMMMUFaultInfo *fi)
@@ -138,13 +138,28 @@ bool arm_cpu_tlb_fill(CPUState *cs, vaddr address, int 
size,
     ARMCPU *cpu = ARM_CPU(cs);
 
 #ifdef CONFIG_USER_ONLY
+    int flags, fsc, exc;
+    unsigned syn;
+
     cpu->env.exception.vaddress = address;
-    if (access_type == MMU_INST_FETCH) {
-        cs->exception_index = EXCP_PREFETCH_ABORT;
+
+    flags = page_get_flags(useronly_clean_ptr(address));
+    if (flags & PAGE_VALID) {
+        fsc = 0xf; /* permission fault, level 3 */
     } else {
-        cs->exception_index = EXCP_DATA_ABORT;
+        fsc = 0x7; /* translation fault, level 3 */
     }
-    cpu_loop_exit_restore(cs, retaddr);
+
+    cpu_restore_state(cs, retaddr, true);
+    if (access_type == MMU_INST_FETCH) {
+        exc = EXCP_PREFETCH_ABORT;
+        syn = syn_insn_abort(0, 0, 0, fsc);
+    } else {
+        exc = EXCP_DATA_ABORT;
+        syn = merge_syn_data_abort(cpu->env.exception.syndrome, 1, 0, 0, 0,
+                                   access_type == MMU_DATA_STORE, fsc);
+    }
+    raise_exception(&cpu->env, exc, syn, 1);
 #else
     hwaddr phys_addr;
     target_ulong page_size;
-- 
2.25.1