From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753262Ab1ABHWi (ORCPT ); Sun, 2 Jan 2011 02:22:38 -0500 Received: from mail.windriver.com ([147.11.1.11]:34847 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753114Ab1ABHWe (ORCPT ); Sun, 2 Jan 2011 02:22:34 -0500 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Yusuke Goda , Matt Fleming , Samuel Ortiz , Paul Mundt , , Andrew Morton , Linus Torvalds , Paul Gortmaker Subject: [34-longterm 067/260] tmio_mmc: don't clear unhandled pending interrupts Date: Sun, 2 Jan 2011 02:16:03 -0500 Message-Id: <1293952756-15010-68-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.3.3 In-Reply-To: <1293952756-15010-1-git-send-email-paul.gortmaker@windriver.com> References: <1293952756-15010-1-git-send-email-paul.gortmaker@windriver.com> X-OriginalArrivalTime: 02 Jan 2011 07:21:19.0757 (UTC) FILETIME=[A6C8C3D0:01CBAA4D] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yusuke Goda commit b78d6c5f51935ba89df8db33a57bacb547aa7325 upstream. Previously, it was possible for ack_mmc_irqs() to clear pending interrupt bits in the CTL_STATUS register, even though the interrupt handler had not been called. This was because of a race that existed when doing a read-modify-write sequence on CTL_STATUS. After the read step in this sequence, if an interrupt occurred (causing one of the bits in CTL_STATUS to be set) the write step would inadvertently clear it. Observed with the TMIO_STAT_RXRDY bit together with CMD53 on AR6002 and BCM4318 SDIO cards in polled mode. This patch eliminates this race by only writing to CTL_STATUS and clearing the interrupts that were passed as an argument to ack_mmc_irqs()." [matt@console-pimps.org: rewrote changelog] Signed-off-by: Yusuke Goda Acked-by: Magnus Damm " Tested-by: Arnd Hannemann " Acked-by: Ian Molton Cc: Matt Fleming Cc: Samuel Ortiz Cc: Paul Mundt Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Paul Gortmaker --- drivers/mmc/host/tmio_mmc.h | 5 +---- 1 files changed, 1 insertions(+), 4 deletions(-) diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h index dafecfb..1836ed9 100644 --- a/drivers/mmc/host/tmio_mmc.h +++ b/drivers/mmc/host/tmio_mmc.h @@ -80,10 +80,7 @@ #define ack_mmc_irqs(host, i) \ do { \ - u32 mask;\ - mask = sd_ctrl_read32((host), CTL_STATUS); \ - mask &= ~((i) & TMIO_MASK_IRQ); \ - sd_ctrl_write32((host), CTL_STATUS, mask); \ + sd_ctrl_write32((host), CTL_STATUS, ~(i)); \ } while (0) -- 1.7.3.3