linux-kernel - [PATCH 09/14] ubi: fastmap: Relax size check

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Date:   Wed, 13 Jun 2018 23:23:39 +0200
From:   Richard Weinberger <richard@....at>
To:     linux-mtd@...ts.infradead.org
Cc:     linux-kernel@...r.kernel.org, Richard Weinberger <richard@....at>
Subject: [PATCH 09/14] ubi: fastmap: Relax size check

While attaching via fastmap we verify whether the found fastmap
is as large as we have computed.
With preseeded Fastmaps this assumtion can fail since ubinize cannot
know the total size of the MTD and uses the number if used PEBs for
the calculation.
Therefore the found fastmap might be smaller than the kernel expects.

Signed-off-by: Richard Weinberger <richard@....at>
---
 drivers/mtd/ubi/fastmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
index 09a9d3a0ccf5..dabeb01af24a 100644
--- a/drivers/mtd/ubi/fastmap.c
+++ b/drivers/mtd/ubi/fastmap.c
@@ -1168,7 +1168,7 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 	}
 
 	fm_size = ubi->leb_size * used_blocks;
-	if (fm_size != ubi->fm_size) {
+	if (fm_size > ubi->fm_size) {
 		ubi_err(ubi, "bad fastmap size: %zi, expected: %zi",
 			fm_size, ubi->fm_size);
 		ret = UBI_BAD_FASTMAP;
-- 
2.13.6