From 0f5ae3d2e9f49af55eb2a9b7cb54b4c0c2373017 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Sun, 14 May 2006 01:40:50 +0100 Subject: [PATCH] [MTD] Deal correctly with NOR chips which are smaller than the map window We used to calculate the number of chips to be zero, allocate an array of that size, then nasty things would happen when we attempt to access the first object in that zero-sized array. Now, if the number of _full_ chips that would fit into the map is zero, we allocate an array of one anyway, and then artificially reduce the total size of the resulting MTD device to fit in the map. Signed-off-by: David Woodhouse --- drivers/mtd/chips/gen_probe.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/chips/gen_probe.c b/drivers/mtd/chips/gen_probe.c index 9b252d2e4a..b2d30525c0 100644 --- a/drivers/mtd/chips/gen_probe.c +++ b/drivers/mtd/chips/gen_probe.c @@ -37,8 +37,15 @@ struct mtd_info *mtd_do_chip_probe(struct map_info *map, struct chip_probe *cp) if (!mtd) mtd = check_cmd_set(map, 0); /* Then the secondary */ - if (mtd) + if (mtd) { + if (mtd->size > map->size) { + printk(KERN_WARNING "Reducing visibility of %lKiB chip to %lKiB\n", + (unsigned long)mtd->size >> 10, + (unsigned long)map->size >> 10); + mtd->size = map->size; + } return mtd; + } printk(KERN_WARNING"gen_probe: No supported Vendor Command Set found\n"); @@ -100,7 +107,12 @@ static struct cfi_private *genprobe_ident_chips(struct map_info *map, struct chi * Align bitmap storage size to full byte. */ max_chips = map->size >> cfi.chipshift; - mapsize = (max_chips / 8) + ((max_chips % 8) ? 1 : 0); + if (!max_chips) { + printk(KERN_WARNING "NOR chip too large to fit in mapping. Attempting to cope...\n"); + max_chips = 1; + } + + mapsize = (max_chips + BITS_PER_LONG-1) / BITS_PER_LONG; chip_map = kmalloc(mapsize, GFP_KERNEL); if (!chip_map) { printk(KERN_WARNING "%s: kmalloc failed for CFI chip map\n", map->name); -- 2.39.5