selftests/ublk: fix garbage output in foreground mode

Initialize _evtfd to -1 in struct dev_ctx to prevent garbage output
when running kublk in foreground mode. Without this, _evtfd is
zero-initialized to 0 (stdin), and ublk_send_dev_event() writes
binary data to stdin which appears as garbage on the terminal.

Also fix debug message format string.

Fixes: 6aecda00b7d1 ("selftests: ublk: add kernel selftests for ublk")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/tools/testing/selftests/ublk/kublk.c b/tools/testing/selftests/ublk/kublk.c
index 65f59e7b697253f688d005cf9dbb18e5547fd496..f197ad9cc2629828408fb014c0a380b0872ca4f6 100644 (file)
--- a/tools/testing/selftests/ublk/kublk.c
+++ b/tools/testing/selftests/ublk/kublk.c
@@ -1274,7 +1274,7 @@ static int __cmd_dev_add(const struct dev_ctx *ctx)
        }
 
        ret = ublk_start_daemon(ctx, dev);
-       ublk_dbg(UBLK_DBG_DEV, "%s: daemon exit %d\b", ret);
+       ublk_dbg(UBLK_DBG_DEV, "%s: daemon exit %d\n", __func__, ret);
        if (ret < 0)
                ublk_ctrl_del_dev(dev);
 
@@ -1620,6 +1620,7 @@ int main(int argc, char *argv[])
        int option_idx, opt;
        const char *cmd = argv[1];
        struct dev_ctx ctx = {
+               ._evtfd         =       -1,
                .queue_depth    =       128,
                .nr_hw_queues   =       2,
                .dev_id         =       -1,