This is a note to let you know that I've just added the patch titled nvme-pci: use appropriate initial chunk size for HMB allocation to the 4.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nvme-pci-use-appropriate-initial-chunk-size-for-hmb-allocation.patch and it can be found in the queue-4.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 30f92d62e5b41a94de2d0bbd677a6ea2fcfed74f Mon Sep 17 00:00:00 2001 From: Akinobu Mita <akinobu.mita@xxxxxxxxx> Date: Wed, 6 Sep 2017 12:15:31 +0200 Subject: nvme-pci: use appropriate initial chunk size for HMB allocation From: Akinobu Mita <akinobu.mita@xxxxxxxxx> commit 30f92d62e5b41a94de2d0bbd677a6ea2fcfed74f upstream. The initial chunk size for host memory buffer allocation is currently PAGE_SIZE << MAX_ORDER. MAX_ORDER order allocation is usually failed without CONFIG_DMA_CMA. So the HMB allocation is retried with chunk size PAGE_SIZE << (MAX_ORDER - 1) in general, but there is no problem if the retry allocation works correctly. Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> [hch: rebased] Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Keith Busch <keith.busch@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/nvme/host/pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -1677,7 +1677,7 @@ static int nvme_alloc_host_mem(struct nv u32 chunk_size; /* start big and work our way down */ - for (chunk_size = min_t(u64, preferred, PAGE_SIZE << MAX_ORDER); + for (chunk_size = min_t(u64, preferred, PAGE_SIZE * MAX_ORDER_NR_PAGES); chunk_size >= PAGE_SIZE * 2; chunk_size /= 2) { if (!__nvme_alloc_host_mem(dev, preferred, chunk_size)) { Patches currently in stable-queue which might be from akinobu.mita@xxxxxxxxx are queue-4.13/nvme-pci-use-appropriate-initial-chunk-size-for-hmb-allocation.patch queue-4.13/nvme-pci-fix-host-memory-buffer-allocation-fallback.patch