From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f198.google.com (mail-pf0-f198.google.com [209.85.192.198]) by kanga.kvack.org (Postfix) with ESMTP id DEE946B04C2 for ; Thu, 7 Sep 2017 04:46:45 -0400 (EDT) Received: by mail-pf0-f198.google.com with SMTP id e199so17288169pfh.3 for ; Thu, 07 Sep 2017 01:46:45 -0700 (PDT) Received: from smtpbgsg2.qq.com (smtpbgsg2.qq.com. [54.254.200.128]) by mx.google.com with ESMTPS id j6si1622568plt.64.2017.09.07.01.46.43 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 07 Sep 2017 01:46:44 -0700 (PDT) From: Huacai Chen Subject: [PATCH 1/2] mm: dmapool: Align to ARCH_DMA_MINALIGN in non-coherent DMA mode Date: Thu, 7 Sep 2017 16:47:51 +0800 Message-Id: <1504774071-11581-1-git-send-email-chenhc@lemote.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Fuxin Zhang , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huacai Chen , stable@vger.kernel.org In non-coherent DMA mode, kernel uses cache flushing operations to maintain I/O coherency, so the dmapool objects should be aligned to ARCH_DMA_MINALIGN. Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen --- mm/dmapool.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/dmapool.c b/mm/dmapool.c index 4d90a64..2ac6f4a 100644 --- a/mm/dmapool.c +++ b/mm/dmapool.c @@ -140,6 +140,9 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev, else if (align & (align - 1)) return NULL; + if (!plat_device_is_coherent(dev)) + align = max_t(size_t, align, dma_get_cache_alignment()); + if (size == 0) return NULL; else if (size < 4) -- 2.7.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org