This is a note to let you know that I've just added the patch titled ubi: Make volume resize power cut aware to the 3.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ubi-make-volume-resize-power-cut-aware.patch and it can be found in the queue-3.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 4946784bd3924b1374f05eebff2fd68660bae866 Mon Sep 17 00:00:00 2001 From: Richard Weinberger <richard@xxxxxx> Date: Thu, 23 Jun 2016 19:30:38 +0200 Subject: ubi: Make volume resize power cut aware From: Richard Weinberger <richard@xxxxxx> commit 4946784bd3924b1374f05eebff2fd68660bae866 upstream. When the volume resize operation shrinks a volume, LEBs will be unmapped. Since unmapping will not erase these LEBs immediately we have to wait for that operation to finish. Otherwise in case of a power cut right after writing the new volume table the UBI attach process can find more LEBs than the volume table knows. This will render the UBI image unattachable. Fix this issue by waiting for erase to complete and write the new volume table afterward. Reported-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> Signed-off-by: Richard Weinberger <richard@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/mtd/ubi/vmt.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) --- a/drivers/mtd/ubi/vmt.c +++ b/drivers/mtd/ubi/vmt.c @@ -534,13 +534,6 @@ int ubi_resize_volume(struct ubi_volume_ spin_unlock(&ubi->volumes_lock); } - /* Change volume table record */ - vtbl_rec = ubi->vtbl[vol_id]; - vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs); - err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec); - if (err) - goto out_acc; - if (pebs < 0) { for (i = 0; i < -pebs; i++) { err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i); @@ -558,6 +551,24 @@ int ubi_resize_volume(struct ubi_volume_ spin_unlock(&ubi->volumes_lock); } + /* + * When we shrink a volume we have to flush all pending (erase) work. + * Otherwise it can happen that upon next attach UBI finds a LEB with + * lnum > highest_lnum and refuses to attach. + */ + if (pebs < 0) { + err = ubi_wl_flush(ubi, vol_id, UBI_ALL); + if (err) + goto out_acc; + } + + /* Change volume table record */ + vtbl_rec = ubi->vtbl[vol_id]; + vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs); + err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec); + if (err) + goto out_acc; + vol->reserved_pebs = reserved_pebs; if (vol->vol_type == UBI_DYNAMIC_VOLUME) { vol->used_ebs = reserved_pebs; Patches currently in stable-queue which might be from richard@xxxxxx are queue-3.14/ubi-fix-race-condition-between-ubi-device-creation-and-udev.patch queue-3.14/ubi-make-volume-resize-power-cut-aware.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html