From: Richard Henderson <richard.henderson@linaro.org>
Date: Sun, 25 Jul 2021 18:25:21 +0000 (-1000)
Subject: accel/tcg: Report unaligned atomics for user-only
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=fce3f474301a104a0d3a02d7d7b42891dea6338b;p=qemu.git

accel/tcg: Report unaligned atomics for user-only

Use the new cpu_loop_exit_sigbus for atomic_mmu_lookup, which
has access to complete alignment info from the TCGMemOpIdx arg.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---

diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c
index c4f69908e9..1ee64f01fc 100644
--- a/accel/tcg/user-exec.c
+++ b/accel/tcg/user-exec.c
@@ -474,11 +474,22 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr,
                                MemOpIdx oi, int size, int prot,
                                uintptr_t retaddr)
 {
+    MemOp mop = get_memop(oi);
+    int a_bits = get_alignment_bits(mop);
+    void *ret;
+
+    /* Enforce guest required alignment.  */
+    if (unlikely(addr & ((1 << a_bits) - 1))) {
+        MMUAccessType t = prot == PAGE_READ ? MMU_DATA_LOAD : MMU_DATA_STORE;
+        cpu_loop_exit_sigbus(env_cpu(env), addr, t, retaddr);
+    }
+
     /* Enforce qemu required alignment.  */
     if (unlikely(addr & (size - 1))) {
         cpu_loop_exit_atomic(env_cpu(env), retaddr);
     }
-    void *ret = g2h(env_cpu(env), addr);
+
+    ret = g2h(env_cpu(env), addr);
     set_helper_retaddr(retaddr);
     return ret;
 }