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=-6.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,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 EE04FC43441 for ; Sun, 11 Nov 2018 22:33:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B45C221780 for ; Sun, 11 Nov 2018 22:33:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ojh169Vn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B45C221780 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.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 S2404514AbeKLIXz (ORCPT ); Mon, 12 Nov 2018 03:23:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:58596 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391153AbeKLIXy (ORCPT ); Mon, 12 Nov 2018 03:23:54 -0500 Received: from localhost (unknown [206.108.79.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7BB39223C6; Sun, 11 Nov 2018 22:33:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541975636; bh=EYl7qWBeAFsJzIdWyyM0xDsJCOOzGiW3EM0xnbeE7Sc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ojh169VnU3iwwrfW3bHKNhb/GsxHATZfFpcxPKHxF9LRZbdpUe5sWqQiFsaH2yaTH Adgdp27ZtMhq3iEOVh6OiqsS7JW5VABlLvw5AVAlP+ld78yjZFi0f5vc4zfqcIxI2D yJhC8V6G8MTs4i0GV+mtPJEY1Vaiui+nyEoSRjJw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stan Johnson , Finn Thain , Michael Schmitz , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.9 053/141] scsi: esp_scsi: Track residual for PIO transfers Date: Sun, 11 Nov 2018 14:25:12 -0800 Message-Id: <20181111221634.848444000@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181111221627.853046496@linuxfoundation.org> References: <20181111221627.853046496@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Finn Thain [ Upstream commit fd47d919d0c336e7c22862b51ee94927ffea227a ] If a target disconnects during a PIO data transfer the command may fail when the target reconnects: scsi host1: DMA length is zero! scsi host1: cur adr[04380000] len[00000000] The scsi bus is then reset. This happens because the residual reached zero before the transfer was completed. The usual residual calculation relies on the Transfer Count registers. That works for DMA transfers but not for PIO transfers. Fix the problem by storing the PIO transfer residual and using that to correctly calculate bytes_sent. Fixes: 6fe07aaffbf0 ("[SCSI] m68k: new mac_esp scsi driver") Tested-by: Stan Johnson Signed-off-by: Finn Thain Tested-by: Michael Schmitz Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/esp_scsi.c | 1 + drivers/scsi/esp_scsi.h | 2 ++ drivers/scsi/mac_esp.c | 2 ++ 3 files changed, 5 insertions(+) --- a/drivers/scsi/esp_scsi.c +++ b/drivers/scsi/esp_scsi.c @@ -1349,6 +1349,7 @@ static int esp_data_bytes_sent(struct es bytes_sent = esp->data_dma_len; bytes_sent -= ecount; + bytes_sent -= esp->send_cmd_residual; /* * The am53c974 has a DMA 'pecularity'. The doc states: --- a/drivers/scsi/esp_scsi.h +++ b/drivers/scsi/esp_scsi.h @@ -540,6 +540,8 @@ struct esp { void *dma; int dmarev; + + u32 send_cmd_residual; }; /* A front-end driver for the ESP chip should do the following in --- a/drivers/scsi/mac_esp.c +++ b/drivers/scsi/mac_esp.c @@ -426,6 +426,8 @@ static void mac_esp_send_pio_cmd(struct scsi_esp_cmd(esp, ESP_CMD_TI); } } + + esp->send_cmd_residual = esp_count; } static int mac_esp_irq_pending(struct esp *esp)