From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 20E7BC2BA19 for ; Tue, 14 Apr 2020 16:45:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0878420656 for ; Tue, 14 Apr 2020 16:45:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2439563AbgDNQpu (ORCPT ); Tue, 14 Apr 2020 12:45:50 -0400 Received: from mga01.intel.com ([192.55.52.88]:24750 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2437673AbgDNQpq (ORCPT ); Tue, 14 Apr 2020 12:45:46 -0400 IronPort-SDR: UEx0Wz/tcgCqqc+75yEB8UooHTd3KJopeDo88nLZyCZcz9hcQaOvbR1VGrKbIXjIQ/FeeaLvFc HiXXgX9imGUw== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2020 09:45:43 -0700 IronPort-SDR: z7JprYkC0W+GU1lzE/oFAicDp7GOQzPHqlDgEhs7DAGPt7JLtYBPuj0y15Sz0nc6otbpAXgcNr add1aAMJskLQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,383,1580803200"; d="scan'208";a="454616261" Received: from shiyaowa-mobl.ger.corp.intel.com (HELO localhost) ([10.249.43.105]) by fmsmga006.fm.intel.com with ESMTP; 14 Apr 2020 09:45:42 -0700 Date: Tue, 14 Apr 2020 19:45:42 +0300 From: Jarkko Sakkinen To: Hans de Goede Cc: linux-integrity@vger.kernel.org, stable@vger.kernel.org, Peter Huewe , Jason Gunthorpe , Arnd Bergmann , Greg Kroah-Hartman , open list Subject: Re: [PATCH] tpm/tpm_tis: Free IRQ if probing fails Message-ID: <20200414164542.GC32775@linux.intel.com> References: <20200412170412.324200-1-jarkko.sakkinen@linux.intel.com> <20200413180732.GA11147@linux.intel.com> <7df7f8bd-c65e-1435-7e82-b9f4ecd729de@redhat.com> <20200414071349.GA8403@linux.intel.com> <20200414160404.GA32775@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200414160404.GA32775@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 14, 2020 at 07:04:07PM +0300, Jarkko Sakkinen wrote: > On Tue, Apr 14, 2020 at 10:26:32AM +0200, Hans de Goede wrote: > > Hi, > > > > On 4/14/20 9:13 AM, Jarkko Sakkinen wrote: > > > On Mon, Apr 13, 2020 at 08:11:15PM +0200, Hans de Goede wrote: > > > > Hi, > > > > > > > > On 4/13/20 8:07 PM, Jarkko Sakkinen wrote: > > > > > On Mon, Apr 13, 2020 at 12:04:25PM +0200, Hans de Goede wrote: > > > > > > Hi Jarkko, > > > > > > > > > > > > On 4/12/20 7:04 PM, Jarkko Sakkinen wrote: > > > > > > > Call devm_free_irq() if we have to revert to polling in order not to > > > > > > > unnecessarily reserve the IRQ for the life-cycle of the driver. > > > > > > > > > > > > > > Cc: stable@vger.kernel.org # 4.5.x > > > > > > > Reported-by: Hans de Goede > > > > > > > Fixes: e3837e74a06d ("tpm_tis: Refactor the interrupt setup") > > > > > > > Signed-off-by: Jarkko Sakkinen > > > > > > > --- > > > > > > > drivers/char/tpm/tpm_tis_core.c | 5 ++++- > > > > > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > > > > > > > > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > > > > > > > index 27c6ca031e23..ae6868e7b696 100644 > > > > > > > --- a/drivers/char/tpm/tpm_tis_core.c > > > > > > > +++ b/drivers/char/tpm/tpm_tis_core.c > > > > > > > @@ -1062,9 +1062,12 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, > > > > > > > if (irq) { > > > > > > > tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED, > > > > > > > irq); > > > > > > > - if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) > > > > > > > + if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) { > > > > > > > dev_err(&chip->dev, FW_BUG > > > > > > > "TPM interrupt not working, polling instead\n"); > > > > > > > + devm_free_irq(chip->dev.parent, priv->irq, > > > > > > > + chip); > > > > > > > + } > > > > > > > > > > > > My initial plan was actually to do something similar, but if the probe code > > > > > > is actually ever fixed to work as intended again then this will lead to a > > > > > > double free as then the IRQ-test path of tpm_tis_send() will have called > > > > > > disable_interrupts() which already calls devm_free_irq(). > > > > > > > > > > > > You could check for chip->irq != 0 here to avoid that. > > > > Erm in case you haven't figured it out yet this should be priv->irq != 0, sorry. > > Yup. > > > > > > > > > > > > > But it all is rather messy, which is why I went with the "#if 0" approach > > > > > > in my patch. > > > > > > > > > > I think it is right way to fix it. It is a bug independent of the issue > > > > > we are experiencing. > > > > > > > > > > However, what you are suggesting should be done in addition. Do you have > > > > > a patch in place or do you want me to refine mine? > > > > > > > > I do not have a patch ready for this, if you can refine yours that would > > > > be great. > > > > > > Thanks! Just wanted to confirm. > > > > And thank you for working on a (temporary?) fix for this. > > As far as I see it, it is orthogonal fix that needs to be backported > to stable kernels. This bug predates the issue we're seeing now. Hey, I came to other thoughts on "how". Would probably make sense to always call disable_interrupts() aka no sense to add two separate code paths. What do you think? /Jarkko