Re: [PATCH 1/3] linux-user/arm: Implement __kernel_memory_barrier

[Laurent Vivier]

Le 14/03/2022 à 05:43, Richard Henderson a écrit :

This fallback syscall was stubbed out.
It would only matter for emulating pre-armv6.

Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
  linux-user/arm/cpu_loop.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/linux-user/arm/cpu_loop.c b/linux-user/arm/cpu_loop.c
index 032e1ffddf..a0e43b261c 100644
--- a/linux-user/arm/cpu_loop.c
+++ b/linux-user/arm/cpu_loop.c
@@ -158,7 +158,7 @@ do_kernel_trap(CPUARMState *env)

switch (env->regs[15]) {

      case 0xffff0fa0: /* __kernel_memory_barrier */
-        /* ??? No-op. Will need to do better for SMP.  */
+        smp_mb();
          break;
      case 0xffff0fc0: /* __kernel_cmpxchg */
           /* XXX: This only works between threads, not between processes.

Applied to my linux-user-for-7.0 branch.

Thanks,
Laurent