Patch "mtd: parsers: bcm47xxpart: Fix halfblock reads" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    mtd: parsers: bcm47xxpart: Fix halfblock reads

to the 5.15-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:
     mtd-parsers-bcm47xxpart-fix-halfblock-reads.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 3dfdf77e2e1d1fca79cda91d25811a4051bc66d5
Author: Linus Walleij <linus.walleij@xxxxxxxxxx>
Date:   Tue Oct 18 11:11:29 2022 +0200

    mtd: parsers: bcm47xxpart: Fix halfblock reads
    
    [ Upstream commit 05e258c6ec669d6d18c494ea03d35962d6f5b545 ]
    
    There is some code in the parser that tries to read 0x8000
    bytes into a block to "read in the middle" of the block. Well
    that only works if the block is also 0x10000 bytes all the time,
    else we get these parse errors as we reach the end of the flash:
    
    spi-nor spi0.0: mx25l1606e (2048 Kbytes)
    mtd_read error while parsing (offset: 0x200000): -22
    mtd_read error while parsing (offset: 0x201000): -22
    (...)
    
    Fix the code to do what I think was intended.
    
    Cc: stable@xxxxxxxxxxxxxxx
    Fixes: f0501e81fbaa ("mtd: bcm47xxpart: alternative MAGIC for board_data partition")
    Cc: Rafał Miłecki <zajec5@xxxxxxxxx>
    Cc: Florian Fainelli <f.fainelli@xxxxxxxxx>
    Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
    Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
    Link: https://lore.kernel.org/linux-mtd/20221018091129.280026-1-linus.walleij@xxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/mtd/parsers/bcm47xxpart.c b/drivers/mtd/parsers/bcm47xxpart.c
index 50fcf4c2174b..13daf9bffd08 100644
--- a/drivers/mtd/parsers/bcm47xxpart.c
+++ b/drivers/mtd/parsers/bcm47xxpart.c
@@ -233,11 +233,11 @@ static int bcm47xxpart_parse(struct mtd_info *master,
 		}
 
 		/* Read middle of the block */
-		err = mtd_read(master, offset + 0x8000, 0x4, &bytes_read,
+		err = mtd_read(master, offset + (blocksize / 2), 0x4, &bytes_read,
 			       (uint8_t *)buf);
 		if (err && !mtd_is_bitflip(err)) {
 			pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
-			       offset + 0x8000, err);
+			       offset + (blocksize / 2), err);
 			continue;
 		}