5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Damien Le Moal <dlemoal@xxxxxxxxxx> [ Upstream commit b164316808ec5de391c3e7b0148ec937d32d280d ] A zoned device with a smaller last zone together with a zone capacity smaller than the zone size does make any sense as that does not correspond to any possible setup for a real device: 1) For ZNS and zoned UFS devices, all zones are always the same size. 2) For SMR HDDs, all zones always have the same capacity. In other words, if we have a smaller last runt zone, then this zone capacity should always be equal to the zone size. Add a check in null_init_zoned_dev() to prevent a configuration to have both a smaller zone size and a zone capacity smaller than the zone size. Signed-off-by: Damien Le Moal <dlemoal@xxxxxxxxxx> Reviewed-by: Niklas Cassel <cassel@xxxxxxxxxx> Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx> Link: https://lore.kernel.org/r/20240530054035.491497-2-dlemoal@xxxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/block/null_blk/zoned.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/block/null_blk/zoned.c b/drivers/block/null_blk/zoned.c index 0cdeafd9defcf..174d93a84137b 100644 --- a/drivers/block/null_blk/zoned.c +++ b/drivers/block/null_blk/zoned.c @@ -80,6 +80,17 @@ int null_init_zoned_dev(struct nullb_device *dev, struct request_queue *q) return -EINVAL; } + /* + * If a smaller zone capacity was requested, do not allow a smaller last + * zone at the same time as such zone configuration does not correspond + * to any real zoned device. + */ + if (dev->zone_capacity != dev->zone_size && + dev->size & (dev->zone_size - 1)) { + pr_err("A smaller last zone is not allowed with zone capacity smaller than zone size.\n"); + return -EINVAL; + } + zone_capacity_sects = mb_to_sects(dev->zone_capacity); dev_capacity_sects = mb_to_sects(dev->size); dev->zone_size_sects = mb_to_sects(dev->zone_size); -- 2.43.0