On 09.03.2020 15:22, Miquel Raynal wrote:
Rafał Miłecki <rafal@xxxxxxxxxx> wrote on Mon, 09 Mar 2020 15:19:10
+0100:
On 2020-03-09 15:04, Miquel Raynal wrote:
Rafał Miłecki <zajec5@xxxxxxxxx> wrote on Mon, 9 Mar 2020 08:44:45
+0100:
From: Rafał Miłecki <rafal@xxxxxxxxxx>
This fixes check for partitions that don't start at beginning of their
parents. Missing partition's offset in formula could result in forcing
read-only incorrectly.
Fixes: 6750f61a13a0 ("mtd: improve calculating partition boundaries >> when checking for alignment")
Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
---
drivers/mtd/mtdpart.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 7328c066c5ba..c683b432cc5e 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -524,7 +524,7 @@ static struct mtd_part *allocate_partition(struct >> mtd_info *parent,
part->name);
}
- tmp = part_absolute_offset(parent) + slave->mtd.size;
+ tmp = part_absolute_offset(parent) + slave->offset + >> slave->mtd.size;
I think you are doing the change at the wrong place, if you want to
check where the partition *starts* you should do it a few lines above.
But I think the check should be here as well, probably.
The check where the partition *starts* is OK and I don't mean to change
it. The bug is about calculating absolute *end* address of partition.
Can you detail a little bit then? Because I don't see the issue anymore
even though I am convinced something is wrong here :)
Please consider following partitions layout:
* bcm47xxsflash
├─ boot 0x000000000000-0x000000040000
└┬ firmware 0x000000040000-0x000001000000
├─ linux 0x00000000001c-0x00000018f800
└┬ container 0x00000018f800-0x000000fc0000
├─ foo 0x000000000000-0x000000630800
└─ bar 0x000000630800-0x000000e30800 (size: 0x800000)
Existing (correct) *start* calculation:
bar start: 0 + 0x040000 + 0x18f800 + 0x630800 = 0x800000
Existing (wrong) end calculation:
bar end: 0 + 0x040000 + 0x18f800 + 0x800000 = 0x9cf800
Fixed (correct) end calculation:
bar end: 0 + 0x040000 + 0x18f800 + 0x630800 + 0x800000 = 0x1000000
Because of that existing wrong end calculation I was getting:
mtd: partition "bar" doesn't end on an erase/write block -- force read-only
See:
2 bcm47xxpart partitions found on MTD device bcm47xxsflash
Creating 2 MTD partitions on "bcm47xxsflash":
0x000000000000-0x000000040000 : "boot"
0x000000040000-0x000001000000 : "firmware"
2 trx partitions found on MTD device firmware
Creating 2 MTD partitions on "firmware":
0x00000000001c-0x00000018f800 : "linux"
mtd: partition "linux" doesn't start on an erase/write block boundary -- force read-only
0x00000018f800-0x000000fc0000 : "container"
mtd: partition "container" doesn't start on an erase/write block boundary -- force read-only
2 container partitions found on MTD device container
Creating 2 MTD partitions on "container":
0x000000000000-0x000000630800 : "foo"
mtd: partition "foo" doesn't start on an erase/write block boundary -- force read-only
0x000000630800-0x000000e30800 : "bar"
mtd: partition "bar" doesn't end on an erase/write block -- force read-only
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