Commit 1e8b4763e0 for qemu.org

commit 1e8b4763e0d2c58e97f9e7715712103548d5aae9
Author: Richard Henderson <richard.henderson@linaro.org>
Date:   Thu Jan 8 11:37:16 2026 +1100

    linux-user/arm: Drop CONFIG_ATOMIC64 test

    Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
    Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/linux-user/arm/cpu_loop.c b/linux-user/arm/cpu_loop.c
index cd89b7d6f5..40aefc4c1d 100644
--- a/linux-user/arm/cpu_loop.c
+++ b/linux-user/arm/cpu_loop.c
@@ -146,25 +146,8 @@ static void arm_kernel_cmpxchg64_helper(CPUARMState *env)
     /* Swap if host != guest endianness, for the host cmpxchg below */
     oldval = tswap64(oldval);
     newval = tswap64(newval);
-
-#ifdef CONFIG_ATOMIC64
-    val = qatomic_cmpxchg__nocheck(host_addr, oldval, newval);
+    val = qatomic_cmpxchg(host_addr, oldval, newval);
     cpsr = (val == oldval) * CPSR_C;
-#else
-    /*
-     * This only works between threads, not between processes, but since
-     * the host has no 64-bit cmpxchg, it is the best that we can do.
-     */
-    start_exclusive();
-    val = *host_addr;
-    if (val == oldval) {
-        *host_addr = newval;
-        cpsr = CPSR_C;
-    } else {
-        cpsr = 0;
-    }
-    end_exclusive();
-#endif
     mmap_unlock();

     cpsr_write(env, cpsr, CPSR_C, CPSRWriteByInstr);