4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joakim Tjernlund <joakim.tjernlund@xxxxxxxxxxxx> commit 7b70eb14392a7cf505f9b358d06c33b5af73d1e7 upstream. Currently it is possible to read and/or write to suspend EB's. Writing /dev/mtdX or /dev/mtdblockX from several processes may break the flash state machine. Taken from cfi_cmdset_0001 driver. Signed-off-by: Joakim Tjernlund <joakim.tjernlund@xxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Reviewed-by: Richard Weinberger <richard@xxxxxx> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/mtd/chips/cfi_cmdset_0002.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/drivers/mtd/chips/cfi_cmdset_0002.c +++ b/drivers/mtd/chips/cfi_cmdset_0002.c @@ -812,9 +812,10 @@ static int get_chip(struct map_info *map (mode == FL_WRITING && (cfip->EraseSuspend & 0x2)))) goto sleep; - /* We could check to see if we're trying to access the sector - * that is currently being erased. However, no user will try - * anything like that so we just wait for the timeout. */ + /* Do not allow suspend iff read/write to EB address */ + if ((adr & chip->in_progress_block_mask) == + chip->in_progress_block_addr) + goto sleep; /* Erase suspend */ /* It's harmless to issue the Erase-Suspend and Erase-Resume @@ -2263,6 +2264,7 @@ static int __xipram do_erase_chip(struct chip->state = FL_ERASING; chip->erase_suspended = 0; chip->in_progress_block_addr = adr; + chip->in_progress_block_mask = ~(map->size - 1); INVALIDATE_CACHE_UDELAY(map, chip, adr, map->size, @@ -2352,6 +2354,7 @@ static int __xipram do_erase_oneblock(st chip->state = FL_ERASING; chip->erase_suspended = 0; chip->in_progress_block_addr = adr; + chip->in_progress_block_mask = ~(len - 1); INVALIDATE_CACHE_UDELAY(map, chip, adr, len,
