Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751928AbbKZCwL (ORCPT ); Wed, 25 Nov 2015 21:52:11 -0500 Received: from mailgw02.mediatek.com ([210.61.82.184]:33309 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1750830AbbKZCwH (ORCPT ); Wed, 25 Nov 2015 21:52:07 -0500 X-Listener-Flag: 11101 From: Chaotian Jing To: Ulf Hansson CC: Matthias Brugger , Stephen Boyd , Chaotian Jing , Adrian Hunter , Minda Chen , , , , , Subject: [PATCH] mmc: core: fix __mmc_switch timeout caused by preempt Date: Thu, 26 Nov 2015 10:51:49 +0800 Message-ID: <1448506309-18163-1-git-send-email-chaotian.jing@mediatek.com> X-Mailer: git-send-email 1.8.1.1.dirty MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2554 Lines: 73 there is a time window between __mmc_send_status() and time_afer(), on some eMMC chip, the timeout_ms is only 10ms, if this thread was scheduled out during this period, then, even card has already changes to transfer state by the result of CMD13, this part of code also treat it to timeout error. So, need calculate timeout first, then call __mmc_send_status(), if already timeout and card still in programing state, then treat it to the real timeout error. Signed-off-by: Chaotian Jing --- drivers/mmc/core/mmc_ops.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c index 1f44426..0add634 100644 --- a/drivers/mmc/core/mmc_ops.c +++ b/drivers/mmc/core/mmc_ops.c @@ -489,6 +489,7 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value, unsigned long timeout; u32 status = 0; bool use_r1b_resp = use_busy_signal; + bool expired = false; mmc_retune_hold(host); @@ -544,10 +545,22 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value, /* Must check status to be sure of no errors. */ timeout = jiffies + msecs_to_jiffies(timeout_ms); do { + /* Timeout if the device never leaves the program state. + * must check it firstly to avoid problem caused by preempt. + */ + expired = time_after(jiffies, timeout); + if (send_status) { err = __mmc_send_status(card, &status, ignore_crc); - if (err) + if (err) { goto out; + } else if (expired && + R1_CURRENT_STATE(status) == R1_STATE_PRG) { + pr_err("%s: Card stuck in programming state! %s\n", + mmc_hostname(host), __func__); + err = -ETIMEDOUT; + goto out; + } } if ((host->caps & MMC_CAP_WAIT_WHILE_BUSY) && use_r1b_resp) break; @@ -563,14 +576,6 @@ int __mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value, mmc_delay(timeout_ms); goto out; } - - /* Timeout if the device never leaves the program state. */ - if (time_after(jiffies, timeout)) { - pr_err("%s: Card stuck in programming state! %s\n", - mmc_hostname(host), __func__); - err = -ETIMEDOUT; - goto out; - } } while (R1_CURRENT_STATE(status) == R1_STATE_PRG); err = mmc_switch_status_error(host, status); -- 1.8.1.1.dirty -- 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/