NOWS is one of the annoying "0's based values" in NVMe, where 0 means one and we thus can't detect if it isn't set. Thus a NOWS value of 0 means that the Namespace Optimal Write Size is a single LBA, which is clearly bogus. Ignore the value in that case and don't propagate an io_opt value to the block layer. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- drivers/nvme/host/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index ab0429644fe378..6784fc6e95625e 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2025,7 +2025,8 @@ static bool nvme_update_disk_info(struct nvme_ns *ns, struct nvme_id_ns *id, /* NPWG = Namespace Preferred Write Granularity */ phys_bs = bs * (1 + le16_to_cpu(id->npwg)); /* NOWS = Namespace Optimal Write Size */ - io_opt = bs * (1 + le16_to_cpu(id->nows)); + if (id->nows) + io_opt = bs * (1 + le16_to_cpu(id->nows)); } /* -- 2.43.0
