The following commit has been merged in the linux branch: commit 2eadaad67b2b6bd132eda105128d2d466298b8e3 Author: Artem Bityutskiy Artem.Bityutskiy@nokia.com Date: Wed Sep 30 10:01:28 2009 +0300

UBI: fix backward compatibility

Commit 32bc4820287a1a03982979515949e8ea56eac641 did not fully fix the backward compatibility issues. We still fail to properly handle situations when the first PEB contains non-zero image sequence number, but one of the following PEBs contains zero image sequence number. For example, this may happen if we mount a new image with an old kernel, and then try to mount it in the new kernel.

This patch should fix the issue.

Signed-off-by: Artem Bityutskiy Artem.Bityutskiy@nokia.com

diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c index e7161ad..90af61a 100644 --- a/drivers/mtd/ubi/scan.c +++ b/drivers/mtd/ubi/scan.c @@ -794,16 +794,15 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si, * number. */ image_seq = be32_to_cpu(ech->image_seq); - if (!si->image_seq_set) { + if (!ubi->image_seq && image_seq) ubi->image_seq = image_seq; - si->image_seq_set = 1; - } else if (ubi->image_seq && ubi->image_seq != image_seq) { + if (ubi->image_seq && image_seq && + ubi->image_seq != image_seq) { ubi_err("bad image sequence number %d in PEB %d, " "expected %d", image_seq, pnum, ubi->image_seq); ubi_dbg_dump_ec_hdr(ech); return -EINVAL; } - }

/* OK, we've done with the EC header, let's look at the VID header */ diff --git a/drivers/mtd/ubi/scan.h b/drivers/mtd/ubi/scan.h index bab3169..ff179ad 100644 --- a/drivers/mtd/ubi/scan.h +++ b/drivers/mtd/ubi/scan.h @@ -103,7 +103,6 @@ struct ubi_scan_volume { * @ec_sum: a temporary variable used when calculating @mean_ec * @ec_count: a temporary variable used when calculating @mean_ec * @corr_count: count of corrupted PEBs - * @image_seq_set: indicates @ubi->image_seq is known * * This data structure contains the result of scanning and may be used by other * UBI sub-systems to build final UBI data structures, further error-recovery @@ -127,7 +126,6 @@ struct ubi_scan_info { uint64_t ec_sum; int ec_count; int corr_count; - int image_seq_set; };

struct ubi_device;