Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754901Ab1EFASr (ORCPT ); Thu, 5 May 2011 20:18:47 -0400 Received: from kroah.org ([198.145.64.141]:32849 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754622Ab1EFANW (ORCPT ); Thu, 5 May 2011 20:13:22 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Thu May 5 17:12:08 2011 Message-Id: <20110506001208.762427521@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Thu, 05 May 2011 17:10:47 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Guennadi Liakhovetski , Simon Horman , Magnus Damm , Linus Walleij , Chris Ball Subject: [patch 15/38] mmc: fix a race between card-detect rescan and clock-gate work instances In-Reply-To: <20110506001225.GA10547@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2821 Lines: 88 2.6.38-stable review patch. If anyone has any objections, please let us know. ------------------ From: Guennadi Liakhovetski commit 26fc8775b51484d8c0a671198639c6d5ae60533e upstream. Currently there is a race in the MMC core between a card-detect rescan work and the clock-gating work, scheduled from a command completion. Fix it by removing the dedicated clock-gating mutex and using the MMC standard locking mechanism instead. Signed-off-by: Guennadi Liakhovetski Cc: Simon Horman Cc: Magnus Damm Acked-by: Linus Walleij Signed-off-by: Chris Ball Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/core/host.c | 9 ++++----- include/linux/mmc/host.h | 1 - 2 files changed, 4 insertions(+), 6 deletions(-) --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -94,7 +94,7 @@ static void mmc_host_clk_gate_delayed(st spin_unlock_irqrestore(&host->clk_lock, flags); return; } - mutex_lock(&host->clk_gate_mutex); + mmc_claim_host(host); spin_lock_irqsave(&host->clk_lock, flags); if (!host->clk_requests) { spin_unlock_irqrestore(&host->clk_lock, flags); @@ -104,7 +104,7 @@ static void mmc_host_clk_gate_delayed(st pr_debug("%s: gated MCI clock\n", mmc_hostname(host)); } spin_unlock_irqrestore(&host->clk_lock, flags); - mutex_unlock(&host->clk_gate_mutex); + mmc_release_host(host); } /* @@ -130,7 +130,7 @@ void mmc_host_clk_ungate(struct mmc_host { unsigned long flags; - mutex_lock(&host->clk_gate_mutex); + mmc_claim_host(host); spin_lock_irqsave(&host->clk_lock, flags); if (host->clk_gated) { spin_unlock_irqrestore(&host->clk_lock, flags); @@ -140,7 +140,7 @@ void mmc_host_clk_ungate(struct mmc_host } host->clk_requests++; spin_unlock_irqrestore(&host->clk_lock, flags); - mutex_unlock(&host->clk_gate_mutex); + mmc_release_host(host); } /** @@ -218,7 +218,6 @@ static inline void mmc_host_clk_init(str host->clk_gated = false; INIT_WORK(&host->clk_gate_work, mmc_host_clk_gate_work); spin_lock_init(&host->clk_lock); - mutex_init(&host->clk_gate_mutex); } /** --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -183,7 +183,6 @@ struct mmc_host { struct work_struct clk_gate_work; /* delayed clock gate */ unsigned int clk_old; /* old clock value cache */ spinlock_t clk_lock; /* lock for clk fields */ - struct mutex clk_gate_mutex; /* mutex for clock gating */ #endif /* host specific block data */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/