From 45686b6198bd824f083ff5293f191d78db9d708a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 2 Mar 2016 18:07:12 +0100 Subject: nvme: fix max_segments integer truncation The block layer uses an unsigned short for max_segments. The way we calculate the value for NVMe tends to generate very large 32-bit values, which after integer truncation may lead to a zero value instead of the desired outcome. Signed-off-by: Christoph Hellwig Reported-by: Jeff Lien Tested-by: Jeff Lien Reviewed-by: Keith Busch Signed-off-by: Jens Axboe --- drivers/nvme/host/core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/nvme') diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index cfee6ac..03c4641 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -844,9 +844,11 @@ static void nvme_set_queue_limits(struct nvme_ctrl *ctrl, struct request_queue *q) { if (ctrl->max_hw_sectors) { + u32 max_segments = + (ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1; + blk_queue_max_hw_sectors(q, ctrl->max_hw_sectors); - blk_queue_max_segments(q, - (ctrl->max_hw_sectors / (ctrl->page_size >> 9)) + 1); + blk_queue_max_segments(q, min_t(u32, max_segments, USHRT_MAX)); } if (ctrl->stripe_size) blk_queue_chunk_sectors(q, ctrl->stripe_size >> 9); -- cgit v1.1