From patchwork Thu Jan 2 22:07:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 234539 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 C6308C3276C for ; Thu, 2 Jan 2020 22:53:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99A5E21835 for ; Thu, 2 Jan 2020 22:53:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578005620; bh=CMzUwSsyVQSqBUOiejZscCQQm1OBmrt+0022tPOxSKg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2YCjRZKhbtQU/7+LJIIhZpmKuE7MxyCxHjWS2RR22H6u+Es8ox4cE1A8piNMq5A5r tamokfffZEhP9eXkdfm3Icm8Y5PvPSSeIuBvsnsYbjmbdefbqwWdLrscMuz/gSY/wL o8ZysnIbuuHNTw7iL7C+7Wsb/5iywQx0o1N2M18w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727523AbgABWxf (ORCPT ); Thu, 2 Jan 2020 17:53:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:40978 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729020AbgABWVh (ORCPT ); Thu, 2 Jan 2020 17:21:37 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 6E5E820863; Thu, 2 Jan 2020 22:21:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578003696; bh=CMzUwSsyVQSqBUOiejZscCQQm1OBmrt+0022tPOxSKg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Yg+Rf7smd0Iuw/CYS2Jw8v/FIh+Kgcvs7eUYzRHGl8syJU3zJ8l2xScofcK7dXUp8 texujMJo5oioCPEnh4D3NtJ6ixbZU8C7jbM2meT5N0AMpLoO1J9Ar0X2f3OlTC0OPd 5HktiMckqDq7VR4vN2KomQTYZi1rwHsiTUPYYdWQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Avri Altman , Bean Huo , Subhash Jadavani , Can Guo , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.19 053/114] scsi: ufs: Fix error handing during hibern8 enter Date: Thu, 2 Jan 2020 23:07:05 +0100 Message-Id: <20200102220034.406463258@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200102220029.183913184@linuxfoundation.org> References: <20200102220029.183913184@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Subhash Jadavani [ Upstream commit 6d303e4b19d694cdbebf76bcdb51ada664ee953d ] During clock gating (ufshcd_gate_work()), we first put the link hibern8 by calling ufshcd_uic_hibern8_enter() and if ufshcd_uic_hibern8_enter() returns success (0) then we gate all the clocks. Now let’s zoom in to what ufshcd_uic_hibern8_enter() does internally: It calls __ufshcd_uic_hibern8_enter() and if failure is encountered, link recovery shall put the link back to the highest HS gear and returns success (0) to ufshcd_uic_hibern8_enter() which is the issue as link is still in active state due to recovery! Now ufshcd_uic_hibern8_enter() returns success to ufshcd_gate_work() and hence it goes ahead with gating the UFS clock while link is still in active state hence I believe controller would raise UIC error interrupts. But when we service the interrupt, clocks might have already been disabled! This change fixes for this by returning failure from __ufshcd_uic_hibern8_enter() if recovery succeeds as link is still not in hibern8, upon receiving the error ufshcd_hibern8_enter() would initiate retry to put the link state back into hibern8. Link: https://lore.kernel.org/r/1573798172-20534-8-git-send-email-cang@codeaurora.org Reviewed-by: Avri Altman Reviewed-by: Bean Huo Signed-off-by: Subhash Jadavani Signed-off-by: Can Guo Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/ufs/ufshcd.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 7510d8328d4d..3601e770da16 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3875,15 +3875,24 @@ static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba) ktime_to_us(ktime_sub(ktime_get(), start)), ret); if (ret) { + int err; + dev_err(hba->dev, "%s: hibern8 enter failed. ret = %d\n", __func__, ret); /* - * If link recovery fails then return error so that caller - * don't retry the hibern8 enter again. + * If link recovery fails then return error code returned from + * ufshcd_link_recovery(). + * If link recovery succeeds then return -EAGAIN to attempt + * hibern8 enter retry again. */ - if (ufshcd_link_recovery(hba)) - ret = -ENOLINK; + err = ufshcd_link_recovery(hba); + if (err) { + dev_err(hba->dev, "%s: link recovery failed", __func__); + ret = err; + } else { + ret = -EAGAIN; + } } else ufshcd_vops_hibern8_notify(hba, UIC_CMD_DME_HIBER_ENTER, POST_CHANGE); @@ -3897,7 +3906,7 @@ static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba) for (retries = UIC_HIBERN8_ENTER_RETRIES; retries > 0; retries--) { ret = __ufshcd_uic_hibern8_enter(hba); - if (!ret || ret == -ENOLINK) + if (!ret) goto out; } out: