[PATCH 3.2 047/152] ubi: Fix race condition between ubi device creation and udev

[Ben Hutchings]

3.2.84-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Iosif Harutyunov <iharutyu...@sonicwall.com>

commit 714fb87e8bc05ff78255afc0dca981e8c5242785 upstream.

Install the UBI device object before we arm sysfs.
Otherwise udev tries to read sysfs attributes before UBI is ready and
udev rules will not match.

Signed-off-by: Iosif Harutyunov <iharutyu...@sonicwall.com>
[rw: massaged commit message]
Signed-off-by: Richard Weinberger <rich...@nod.at>
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
 drivers/mtd/ubi/build.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -974,6 +974,9 @@ int ubi_attach_mtd_dev(struct mtd_info *
                        goto out_detach;
        }
 
+       /* Make device "available" before it becomes accessible via sysfs */
+       ubi_devices[ubi_num] = ubi;
+
        err = uif_init(ubi, &ref);
        if (err)
                goto out_detach;
@@ -1017,7 +1020,6 @@ int ubi_attach_mtd_dev(struct mtd_info *
        wake_up_process(ubi->bgt_thread);
        spin_unlock(&ubi->wl_lock);
 
-       ubi_devices[ubi_num] = ubi;
        ubi_notify_all(ubi, UBI_VOLUME_ADDED, NULL);
        return ubi_num;
 
@@ -1028,6 +1030,7 @@ out_uif:
        ubi_assert(ref);
        uif_close(ubi);
 out_detach:
+       ubi_devices[ubi_num] = NULL;
        ubi_wl_close(ubi);
        free_internal_volumes(ubi);
        vfree(ubi->vtbl);