From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH] xen: check return value of xenbus_printf Date: Mon, 19 Oct 2015 15:30:45 +0100 Message-ID: <5624FE95.2080001@citrix.com> References: <1445263840-21187-1-git-send-email-wuninsu@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp02.citrix.com ([66.165.176.63]:22139 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751776AbbJSOcJ (ORCPT ); Mon, 19 Oct 2015 10:32:09 -0400 In-Reply-To: <1445263840-21187-1-git-send-email-wuninsu@gmail.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Insu Yun , dmitry.torokhov@gmail.com, stefano.stabellini@eu.citrix.com, david.vrabel@citrix.com, wei.liu2@citrix.com, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Cc: taesoo@gatech.edu, yeongjin.jang@gatech.edu, insu@gatech.edu, changwoo@gatech.edu Hi, On 19/10/15 15:10, Insu Yun wrote: > Internally, xenbus_printf uses memory allocation, so it can be failed in > memory pressure.Therefore, xenbus_printf's return should be checked > and properly handled. > > Signed-off-by: Insu Yun > --- > drivers/input/misc/xen-kbdfront.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/input/misc/xen-kbdfront.c b/drivers/input/misc/xen-kbdfront.c > index 23d0549..9d465d7 100644 > --- a/drivers/input/misc/xen-kbdfront.c > +++ b/drivers/input/misc/xen-kbdfront.c > @@ -129,8 +129,14 @@ static int xenkbd_probe(struct xenbus_device *dev, > > if (xenbus_scanf(XBT_NIL, dev->otherend, "feature-abs-pointer", "%d", &abs) < 0) > abs = 0; > - if (abs) > - xenbus_printf(XBT_NIL, dev->nodename, "request-abs-pointer", "1"); > + if (abs) { > + ret = xenbus_printf(XBT_NIL, dev->nodename, > + "request-abs-pointer", "1"); The second line of arguments should be aligned to the first parameter. I.e: xenbus_printf(XBT_NIL, dev->nodename, "request-abs-pointer", "1"); See an example in xenkbd_backend_changed. With that fixed: Reviewed-by: Julien Grall > + if (ret) { > + pr_warning("xenkbd: can't request abs-pointer"); Note that checkpatch.pl will print a warning here: WARNING: Prefer pr_warn(... to pr_warning(... #27: FILE: drivers/input/misc/xen-kbdfront.c:136: + pr_warning("xenkbd: can't request abs-pointer"); Although, I'm fine if you don't fix this one. > + abs = 0; > + } > + } > > /* keyboard */ > kbd = input_allocate_device(); > Regards, -- Julien Grall