From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1BAD3C43441 for ; Thu, 29 Nov 2018 06:02:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D4AED2146F for ; Thu, 29 Nov 2018 06:02:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="pSdqYtIX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D4AED2146F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729722AbeK2RGr (ORCPT ); Thu, 29 Nov 2018 12:06:47 -0500 Received: from mail.kernel.org ([198.145.29.99]:43448 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728676AbeK2RGr (ORCPT ); Thu, 29 Nov 2018 12:06:47 -0500 Received: from sasha-vm.mshome.net (unknown [37.142.5.207]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 087842146D; Thu, 29 Nov 2018 06:02:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543471355; bh=DNTpOWcAzpZp6ip2GksZjwoRrXZbwD+fBa7w1pq8f5U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pSdqYtIXT47qt/VGkgi3nPylILqAgtSIse3opST469JcPjVeh3n5TvmT+0E9tNC80 GpnsBgYZZhoKiK7aiMZSzzJDSGHs9WeKIvIvAFLxDoq+NAreDFViToSYr8AtXRIpcT OPgsH/fXlIjSUNUm+tVVjo40G3eHiucKabD/QGjk= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Thor Thayer , Boris Brezillon , Sasha Levin , linux-mtd@lists.infradead.org Subject: [PATCH AUTOSEL 4.14 22/35] mtd: spi-nor: Fix Cadence QSPI page fault kernel panic Date: Thu, 29 Nov 2018 01:00:56 -0500 Message-Id: <20181129060110.159878-22-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181129060110.159878-1-sashal@kernel.org> References: <20181129060110.159878-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thor Thayer [ Upstream commit a6a66f80c85e8e20573ca03fabf32445954a88d5 ] The current Cadence QSPI driver caused a kernel panic sporadically when writing to QSPI. The problem was caused by writing more bytes than needed because the QSPI operated on 4 bytes at a time. [ 11.202044] Unable to handle kernel paging request at virtual address bffd3000 [ 11.209254] pgd = e463054d [ 11.211948] [bffd3000] *pgd=2fffb811, *pte=00000000, *ppte=00000000 [ 11.218202] Internal error: Oops: 7 [#1] SMP ARM [ 11.222797] Modules linked in: [ 11.225844] CPU: 1 PID: 1317 Comm: systemd-hwdb Not tainted 4.17.7-d0c45cd44a8f [ 11.235796] Hardware name: Altera SOCFPGA Arria10 [ 11.240487] PC is at __raw_writesl+0x70/0xd4 [ 11.244741] LR is at cqspi_write+0x1a0/0x2cc On a page boundary limit the number of bytes copied from the tx buffer to remain within the page. This patch uses a temporary buffer to hold the 4 bytes to write and then copies only the bytes required from the tx buffer. Reported-by: Adrian Amborzewicz Signed-off-by: Thor Thayer Signed-off-by: Boris Brezillon Signed-off-by: Sasha Levin --- drivers/mtd/spi-nor/cadence-quadspi.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c index 8d89204b90d2..f22dd34f4f83 100644 --- a/drivers/mtd/spi-nor/cadence-quadspi.c +++ b/drivers/mtd/spi-nor/cadence-quadspi.c @@ -625,9 +625,23 @@ static int cqspi_indirect_write_execute(struct spi_nor *nor, reg_base + CQSPI_REG_INDIRECTWR); while (remaining > 0) { + size_t write_words, mod_bytes; + write_bytes = remaining > page_size ? page_size : remaining; - iowrite32_rep(cqspi->ahb_base, txbuf, - DIV_ROUND_UP(write_bytes, 4)); + write_words = write_bytes / 4; + mod_bytes = write_bytes % 4; + /* Write 4 bytes at a time then single bytes. */ + if (write_words) { + iowrite32_rep(cqspi->ahb_base, txbuf, write_words); + txbuf += (write_words * 4); + } + if (mod_bytes) { + unsigned int temp = 0xFFFFFFFF; + + memcpy(&temp, txbuf, mod_bytes); + iowrite32(temp, cqspi->ahb_base); + txbuf += mod_bytes; + } ret = wait_for_completion_timeout(&cqspi->transfer_complete, msecs_to_jiffies @@ -638,7 +652,6 @@ static int cqspi_indirect_write_execute(struct spi_nor *nor, goto failwr; } - txbuf += write_bytes; remaining -= write_bytes; if (remaining > 0) -- 2.17.1