diff --git a/osal/inc/mpp_common.h b/osal/inc/mpp_common.h
index b4d29e01..60a0b20f 100644
--- a/osal/inc/mpp_common.h
+++ b/osal/inc/mpp_common.h
@@ -40,6 +40,7 @@
 #define MPP_SWAP(type, a, b)    do {type SWAP_tmp = b; b = a; a = SWAP_tmp;} while(0)
 #define MPP_ARRAY_ELEMS(a)      (sizeof(a) / sizeof((a)[0]))
 #define MPP_ALIGN(x, a)         (((x)+(a)-1)&~((a)-1))
+#define MPP_ALIGN_DOWN(x, a)    ((x)&~((a)-1))
 #define MPP_ALIGN_GEN(x, a)     (((x)+(a)-1)/(a)*(a))
 #define MPP_VSWAP(a, b)         { a ^= b; b ^= a; a ^= b; }
 
diff --git a/osal/mpp_dmabuf.cpp b/osal/mpp_dmabuf.cpp
index 8140a883..c800dc6e 100644
--- a/osal/mpp_dmabuf.cpp
+++ b/osal/mpp_dmabuf.cpp
@@ -72,8 +72,8 @@ MPP_RET mpp_dmabuf_sync_partial_begin(RK_S32 fd, RK_S32 ro, RK_U32 offset, RK_U3
             return MPP_OK;
 
         sync.flags = DMA_BUF_SYNC_START | (ro ? DMA_BUF_SYNC_READ : DMA_BUF_SYNC_RW);
-        sync.offset = offset / CACHE_LINE_SIZE;
-        sync.len = MPP_ALIGN(length, CACHE_LINE_SIZE);
+        sync.offset = MPP_ALIGN_DOWN(offset, CACHE_LINE_SIZE);
+        sync.len = MPP_ALIGN(length + offset - sync.offset, CACHE_LINE_SIZE);
 
         ret = ioctl(fd, DMA_BUF_IOCTL_SYNC_PARTIAL, &sync);
         if (ret) {
@@ -103,8 +103,8 @@ MPP_RET mpp_dmabuf_sync_partial_end(RK_S32 fd, RK_S32 ro, RK_U32 offset, RK_U32
             return MPP_OK;
 
         sync.flags = DMA_BUF_SYNC_END | (ro ? DMA_BUF_SYNC_READ : DMA_BUF_SYNC_RW);
-        sync.offset = offset / CACHE_LINE_SIZE;
-        sync.len = MPP_ALIGN(length, CACHE_LINE_SIZE);
+        sync.offset = MPP_ALIGN_DOWN(offset, CACHE_LINE_SIZE);
+        sync.len = MPP_ALIGN(length + offset - sync.offset, CACHE_LINE_SIZE);
 
         ret = ioctl(fd, DMA_BUF_IOCTL_SYNC_PARTIAL, &sync);
         if (ret) {