From 50cdb7c61b019a732fe34635a7cbf2a7487f5e90 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 25 Jul 2017 17:39:07 +0200 Subject: [PATCH] nvme-pci: fix HMB size calculation It's possible the preferred HMB size may not be a multiple of the chunk_size. This patch moves len to function scope and uses that in the for loop increment so the last iteration doesn't cause the total size to exceed the allocated HMB size. Based on an earlier patch from Keith Busch. Signed-off-by: Christoph Hellwig Reported-by: Dan Carpenter Reviewed-by: Keith Busch Fixes: 87ad72a59a38 ("nvme-pci: implement host memory buffer support") --- drivers/nvme/host/pci.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 8569ee771269..cd888a47d0fc 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1619,7 +1619,7 @@ static void nvme_free_host_mem(struct nvme_dev *dev) static int nvme_alloc_host_mem(struct nvme_dev *dev, u64 min, u64 preferred) { struct nvme_host_mem_buf_desc *descs; - u32 chunk_size, max_entries; + u32 chunk_size, max_entries, len; int i = 0; void **bufs; u64 size = 0, tmp; @@ -1638,10 +1638,10 @@ retry: if (!bufs) goto out_free_descs; - for (size = 0; size < preferred; size += chunk_size) { - u32 len = min_t(u64, chunk_size, preferred - size); + for (size = 0; size < preferred; size += len) { dma_addr_t dma_addr; + len = min_t(u64, chunk_size, preferred - size); bufs[i] = dma_alloc_attrs(dev->dev, len, &dma_addr, GFP_KERNEL, DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_NO_WARN); if (!bufs[i]) -- 2.20.1