From mboxrd@z Thu Jan 1 00:00:00 1970 From: Darren Hart Subject: Re: [PATCH 2/2] intel_pmc_core: avoid boot time warning for !CONFIG_DEBUGFS_FS Date: Wed, 12 Oct 2016 01:13:18 -0700 Message-ID: <20161012081318.GA4411@f23x64.localdomain> References: <20161010111313.119658-1-arnd@arndb.de> <20161010111313.119658-2-arnd@arndb.de> <20161010122917.GA2377@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20161010122917.GA2377@kroah.com> Sender: linux-kernel-owner@vger.kernel.org To: Greg Kroah-Hartman Cc: Arnd Bergmann , Andy Shevchenko , Rajneesh Bhardwaj , Darren Hart , Nicolai Stange , Vishwanath Somayaji , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: platform-driver-x86.vger.kernel.org On Mon, Oct 10, 2016 at 02:29:17PM +0200, Greg Kroah-Hartman wrote: > On Mon, Oct 10, 2016 at 01:12:58PM +0200, Arnd Bergmann wrote: > > While looking at a patch that introduced a compile-time warning > > "‘pmc_core_dev_state_get’ defined but not used" (I sent a patch > > for debugfs to fix it), I noticed that the same patch caused > > it in intel_pmc_core also introduced a bogus run-time warning: > > "PMC Core: debugfs register failed". > > > > The problem is the IS_ERR_OR_NULL() check that as usual gets > > things wrong: when CONFIG_DEBUGFS_FS is disabled, > > debugfs_create_dir() fails with an error code, and we don't > > need to warn about it, unlike the case in which it returns > > NULL. > > > > This reverts the driver to the previous state of not warning > > about CONFIG_DEBUGFS_FS being disabled. I chose not to > > restore the driver to making a runtime error in debugfs > > fatal in pmc_core_probe(). > > > > Fixes: df2294fb6428 ("intel_pmc_core: Convert to DEFINE_DEBUGFS_ATTRIBUTE") > > Signed-off-by: Arnd Bergmann > > --- > > drivers/platform/x86/intel_pmc_core.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/platform/x86/intel_pmc_core.c b/drivers/platform/x86/intel_pmc_core.c > > index 520b58a04daa..e8b1b836ca2d 100644 > > --- a/drivers/platform/x86/intel_pmc_core.c > > +++ b/drivers/platform/x86/intel_pmc_core.c > > @@ -100,7 +100,7 @@ static int pmc_core_dbgfs_register(struct pmc_dev *pmcdev) > > struct dentry *dir, *file; > > > > dir = debugfs_create_dir("pmc_core", NULL); > > - if (IS_ERR_OR_NULL(dir)) > > + if (!dir) > > return -ENOMEM; > > Hah, no, you shouldn't ever care about any return value being "wrong" > from debugfs, the code should just continue on as normal. > > And yes, you are correct, the IS_ERR_OR_NULL() is totally wrong. > > thanks, > > greg k-h > Thanks Arnd and Greg, appreciate the catch and the fix. Applied. -- Darren Hart Intel Open Source Technology Center