selftests: ublk: fix starting ublk device

Firstly ublk char device node may not be created by udev yet, so wait
a while until it can be opened or timeout.

Secondly delete created ublk device in case of start failure, otherwise
the device becomes zombie.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250321135324.259677-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/tools/testing/selftests/ublk/file_backed.c b/tools/testing/selftests/ublk/file_backed.c
index 8a07356eccaf6ed8d414dd8df3515101bece4975..570a5158b665506649a92a99ebf682dd37205986 100644 (file)
--- a/tools/testing/selftests/ublk/file_backed.c
+++ b/tools/testing/selftests/ublk/file_backed.c
@@ -196,11 +196,13 @@ static int ublk_loop_tgt_init(struct ublk_dev *dev)
                },
        };
 
-       assert(dev->tgt.nr_backing_files == 1);
        ret = backing_file_tgt_init(dev);
        if (ret)
                return ret;
 
+       if (dev->tgt.nr_backing_files != 1)
+               return -EINVAL;
+
        bytes = dev->tgt.backing_file_size[0];
        dev->tgt.dev_size = bytes;
        p.basic.dev_sectors = bytes >> 9;

diff --git a/tools/testing/selftests/ublk/kublk.c b/tools/testing/selftests/ublk/kublk.c
index 148355717ee723187955b0aa1ef631671b896716..11005a87bcfaa25c4b6de8f022870b981f38afd3 100644 (file)
--- a/tools/testing/selftests/ublk/kublk.c
+++ b/tools/testing/selftests/ublk/kublk.c
@@ -379,26 +379,34 @@ static int ublk_queue_init(struct ublk_queue *q)
        return -ENOMEM;
 }
 
+#define WAIT_USEC      100000
+#define MAX_WAIT_USEC  (3 * 1000000)
 static int ublk_dev_prep(struct ublk_dev *dev)
 {
        int dev_id = dev->dev_info.dev_id;
+       unsigned int wait_usec = 0;
+       int ret = 0, fd = -1;
        char buf[64];
-       int ret = 0;
 
        snprintf(buf, 64, "%s%d", UBLKC_DEV, dev_id);
-       dev->fds[0] = open(buf, O_RDWR);
-       if (dev->fds[0] < 0) {
-               ret = -EBADF;
-               ublk_err("can't open %s, ret %d\n", buf, dev->fds[0]);
-               goto fail;
+
+       while (wait_usec < MAX_WAIT_USEC) {
+               fd = open(buf, O_RDWR);
+               if (fd >= 0)
+                       break;
+               usleep(WAIT_USEC);
+               wait_usec += WAIT_USEC;
+       }
+       if (fd < 0) {
+               ublk_err("can't open %s %s\n", buf, strerror(errno));
+               return -1;
        }
 
+       dev->fds[0] = fd;
        if (dev->tgt.ops->init_tgt)
                ret = dev->tgt.ops->init_tgt(dev);
-
-       return ret;
-fail:
-       close(dev->fds[0]);
+       if (ret)
+               close(dev->fds[0]);
        return ret;
 }
 
@@ -856,6 +864,8 @@ 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);
+       if (ret < 0)
+               ublk_ctrl_del_dev(dev);
 
 fail:
        if (ret < 0)