exec: fix a glitch in checking dma r/w access

While checking r/w access in 'memory_access_is_direct' routine
a glitch in the expression leads to segmentation fault while
performing dma read operation.

Reported-by: Donghai Zdh <donghai.zdh@alibaba-inc.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>

diff --git a/exec.c b/exec.c
index 46fe70ed49f85d0638061aa5b09f1f9d521b0bd3..581b57c62d987c3fb7573db134d53a972ebb652d 100644 (file)
--- a/exec.c
+++ b/exec.c
@@ -347,7 +347,7 @@ address_space_translate_internal(AddressSpaceDispatch *d, hwaddr addr, hwaddr *x
 static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write)
 {
     if (memory_region_is_ram(mr)) {
-        return !(is_write && mr->readonly);
+        return (is_write && !mr->readonly);
     }
     if (memory_region_is_romd(mr)) {
         return !is_write;