From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ob0-f193.google.com ([209.85.214.193]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1arAN7-0004b0-4i for linux-mtd@lists.infradead.org; Fri, 15 Apr 2016 20:29:45 +0000 Received: by mail-ob0-f193.google.com with SMTP id ds1so710222obc.3 for ; Fri, 15 Apr 2016 13:29:24 -0700 (PDT) From: Franklin S Cooper Jr To: boris.brezillon@free-electrons.com, dwmw2@infradead.org, computersforpeace@gmail.com, tony@atomide.com, rogerq@ti.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org Cc: "Cooper Jr., Franklin" Subject: [PATCH 2/2] mtd: nand: omap2: Fix high memory dma prefetch transfer Date: Fri, 15 Apr 2016 15:28:59 -0500 Message-Id: <1460752139-12742-3-git-send-email-fcooper@ti.com> In-Reply-To: <1460752139-12742-1-git-send-email-fcooper@ti.com> References: <1460752139-12742-1-git-send-email-fcooper@ti.com> List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: "Cooper Jr., Franklin" Based on DMA documentation and testing using high memory buffer when doing dma transfers can lead to various issues including kernel panics. To workaround this simply use cpu copy. Signed-off-by: Franklin S Cooper Jr --- drivers/mtd/nand/omap2.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 762e0ed..8d0ae3a 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -467,17 +467,8 @@ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr, int ret; u32 val; - if (addr >= high_memory) { - struct page *p1; - - if (((size_t)addr & PAGE_MASK) != - ((size_t)(addr + len - 1) & PAGE_MASK)) - goto out_copy; - p1 = vmalloc_to_page(addr); - if (!p1) - goto out_copy; - addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK); - } + if (!virt_addr_valid(addr)) + goto out_copy; sg_init_one(&sg, addr, len); n = dma_map_sg(info->dma->device->dev, &sg, 1, dir); -- 2.7.0