Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751651AbbFYGte (ORCPT ); Thu, 25 Jun 2015 02:49:34 -0400 Received: from mail-wi0-f173.google.com ([209.85.212.173]:34461 "EHLO mail-wi0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750919AbbFYGt2 (ORCPT ); Thu, 25 Jun 2015 02:49:28 -0400 Date: Thu, 25 Jun 2015 08:49:22 +0200 From: Ingo Molnar To: "Luis R. Rodriguez" Cc: bp@suse.de, andy@silverblocksystems.net, mchehab@osg.samsung.com, dledford@redhat.com, fengguang.wu@intel.com, linux-media@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, "Luis R. Rodriguez" Subject: Re: [PATCH v2 1/2] x86/mm/pat, drivers/infiniband/ipath: replace WARN() with pr_warn() Message-ID: <20150625064922.GA5339@gmail.com> References: <1435166600-11956-1-git-send-email-mcgrof@do-not-panic.com> <1435166600-11956-2-git-send-email-mcgrof@do-not-panic.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1435166600-11956-2-git-send-email-mcgrof@do-not-panic.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2033 Lines: 63 * Luis R. Rodriguez wrote: > From: "Luis R. Rodriguez" > > WARN() may confuse users, fix that. ipath_init_one() is part the > device's probe so this would only be triggered if a corresponding > device was found. > > Signed-off-by: Luis R. Rodriguez > --- > drivers/infiniband/hw/ipath/ipath_driver.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c > index 2d7e503..871dbe5 100644 > --- a/drivers/infiniband/hw/ipath/ipath_driver.c > +++ b/drivers/infiniband/hw/ipath/ipath_driver.c > @@ -31,6 +31,8 @@ > * SOFTWARE. > */ > > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > #include > #include > #include > @@ -399,8 +401,8 @@ static int ipath_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) > u32 bar0 = 0, bar1 = 0; > > #ifdef CONFIG_X86_64 > - if (WARN(pat_enabled(), > - "ipath needs PAT disabled, boot with nopat kernel parameter\n")) { > + if (pat_enabled()) { > + pr_warn("ipath needs PAT disabled, boot with nopat kernel parameter\n"); > ret = -ENODEV; > goto bail; > } So driver init will always fail with this on modern kernels. Btw., on a second thought, ipath uses MTRRs to enable WC: ret = ipath_enable_wc(dd); if (ret) ret = 0; Note how it ignores any failures - the driver still works even if WC was not enabled. So why don't you simply extend ipath_enable_wc() to generate the warning message and return -EINVAL - which still keeps the driver working on modern kernels? Just inform the user about 'nopat' if he wants WC for this driver. Thanks, Ingo -- 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/