diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index e91260a6156b..15e5e6ec5968 100644
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -640,7 +640,7 @@ int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
 			return -ENOMEM;
 	}
 
-	mmap_offset = reg.bgid << IORING_OFF_PBUF_SHIFT;
+	mmap_offset = (unsigned long)reg.bgid << IORING_OFF_PBUF_SHIFT;
 	ring_size = flex_array_size(br, bufs, reg.ring_entries);
 
 	memset(&rd, 0, sizeof(rd));