From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: [RFC] xhci: clear port_remote_wakeup on device disconnection From: Mathias Nyman Message-Id: Date: Wed, 20 Mar 2019 15:55:02 +0200 To: Nicolas Saenz Julienne , Oliver Neukum , Mathias Nyman Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org List-ID: T24gMTkuMy4yMDE5IDE2LjU0LCBOaWNvbGFzIFNhZW56IEp1bGllbm5lIHdyb3RlOgo+IEhpIE9s aXZlciwgdGhhbmtzIGZvciB0aGUgcmV2aWV3IQo+IAo+IE9uIFR1ZSwgMjAxOS0wMy0xOSBhdCAx MjowMSArMDEwMCwgT2xpdmVyIE5ldWt1bSB3cm90ZToKPj4gT24gTW8sIDIwMTktMDMtMTggYXQg MTg6MDAgKzAxMDAsIE5pY29sYXMgU2FlbnogSnVsaWVubmUgd3JvdGU6Cj4+PiBUaGlzIHBhdGNo IGNsZWFycyAicG9ydF9yZW1vdGVfd2FrZXVwIiB1cG9uIGRldGVjdGluZyBhIGRldmljZQo+Pj4g ZGlzY29ubmVjdGlvbi4gTWFraW5nIHN1cmUgdGhlIGFib3ZlIG1lbnRpb25lZCBzaXR1YXRpb24g ZG9lc24ndCB0cmlnZ2VyCj4+PiBhIFBNIGJ1c3lsb29wLgo+Pgo+PiBIaSwKPj4KPj4gdGhhdCBp cyBhbiBpbnRlcmVzdGluZyByYWNlIGNvbmRpdGlvbi4KPj4KClR1cm5zIG91dCB0aGF0IHBvcnRf cmVtb3RlX3dha2V1cCB3YXMgb25seSBwcm9wZXJseSBjbGVhcmVkIGluIGNhc2Ugb2YgYQpzdWNj ZXNzZnVsIHJlc3VtZSB3aGVyZSBwb3J0IHN0YXlzIGluIFUwLCBvciBpbiBjYXNlIG9mIGFuIGVy cm9yIHdoZXJlIHBvcnQKZ29lcyB0byBpbmFjdGl2ZSBzdGF0ZS4KCkluIGFsbCBvdGhlciBjYXNl cyBwb3J0X3JlbW90ZV93YWtldXAgYml0IHdhcyBsZWZ0IHVuY2xlYXJlZC4KCj4+PiBTaWduZWQt b2ZmLWJ5OiBOaWNvbGFzIFNhZW56IEp1bGllbm5lIDxuc2FlbnpqdWxpZW5uZUBzdXNlLmRlPgo+ Pj4gLS0tCj4+PiAgIGRyaXZlcnMvdXNiL2hvc3QveGhjaS1odWIuYyB8IDMgKysrCj4+PiAgIDEg ZmlsZSBjaGFuZ2VkLCAzIGluc2VydGlvbnMoKykKPj4+Cj4+PiBkaWZmIC0tZ2l0IGEvZHJpdmVy cy91c2IvaG9zdC94aGNpLWh1Yi5jIGIvZHJpdmVycy91c2IvaG9zdC94aGNpLWh1Yi5jCj4+PiBp bmRleCBlMmVlY2U2OTM2NTUuLmJlYTg1M2Y0NWFlYyAxMDA2NDQKPj4+IC0tLSBhL2RyaXZlcnMv dXNiL2hvc3QveGhjaS1odWIuYwo+Pj4gKysrIGIvZHJpdmVycy91c2IvaG9zdC94aGNpLWh1Yi5j Cj4+PiBAQCAtOTQyLDYgKzk0Miw5IEBAIHN0YXRpYyB2b2lkIHhoY2lfZ2V0X3VzYjNfcG9ydF9z dGF0dXMoc3RydWN0IHhoY2lfcG9ydAo+Pj4gKnBvcnQsIHUzMiAqc3RhdHVzLAo+Pj4gICAJCQli dXNfc3RhdGUtPnN1c3BlbmRlZF9wb3J0cyAmPSB+KDEgPDwgcG9ydG51bSk7Cj4+PiAgIAl9Cj4+ PiAgIAo+Pj4gKwlpZiAoIShwb3J0c2MgJiBQT1JUX0NPTk5FQ1QpKQo+Pj4gKwkJYnVzX3N0YXRl LT5wb3J0X3JlbW90ZV93YWtldXAgJj0gfigxIDw8IHBvcnRudW0pOwo+Pj4gKwoKQSBjaGVjayBs aWtlIHRoaXMgc2hvdWxkIGNvdmVyIHRoZSBmYWlsaW5nIHJlc3VtZSBjYXNlcywgdGhhbmtzCgpX ZSBhbHNvIHNhdyBhIGNhc2Ugd2hlbiBhIHN1Y2Nlc3NmdWwgcmVzdW1lIHdhcyBtaXNzZWQgYXMg cG9ydCB3ZW50IGludG8gVTEKTGluayBwb3dlciBzYXZlIHN0YXRlIChyZXN1bWUtPlUwLT5VMSkg YmVmb3JlIHhoY2kgZHJpdmVyIHJlYWQgdGhlIHBvcnQgc3RhdHVzLgoKQSBwYXRjaCBhZGRpbmcg VTEgYW5kIFUyIHRvIHN1Y2Nlc3NmdWwgcmVzdW1lIHN0YXRlcyBpcyBwZW5kaW5nIGluIG15IGZv ci11c2ItbGludXMKYnJhbmNoIGZvciB0aGlzLgoKPj4KPj4gV2h5IGFyZSB5b3UgcHV0dGluZyB0 aGF0IGxvZ2ljIGludG8geGhjaV9nZXRfdXNiM19wb3J0X3N0YXR1cygpPwo+PiBJdCBsb29rcyB0 byBtZSBsaWtlIHRoZXJlIGlzIGFscmVhZHkgc29tZXRoaW5nIHJlbGF0ZWQgaW4gdGhlIGNhbGxl cgo+IAo+IFlvdSdyZSByaWdodCwgeGhjaV9nZXRfdXNiM19wb3J0X3N0YXR1cygpIGlzIG5vdCB0 aGUgaWRlYWwgc3BvdCBJJ2xsIG1vdmUgdGhlCj4gY29kZSB0aGVyZS4KPiAKClNvdW5kcyBnb29k LCB0aGFua3MKCi1NYXRoaWFzCg== 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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 D5BF7C43381 for ; Wed, 20 Mar 2019 13:52:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AED852175B for ; Wed, 20 Mar 2019 13:52:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727805AbfCTNww (ORCPT ); Wed, 20 Mar 2019 09:52:52 -0400 Received: from mga17.intel.com ([192.55.52.151]:22797 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726239AbfCTNww (ORCPT ); Wed, 20 Mar 2019 09:52:52 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Mar 2019 06:52:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,249,1549958400"; d="scan'208";a="124260986" Received: from mattu-haswell.fi.intel.com (HELO [10.237.72.164]) ([10.237.72.164]) by orsmga007.jf.intel.com with ESMTP; 20 Mar 2019 06:52:49 -0700 Subject: Re: [RFC] xhci: clear port_remote_wakeup on device disconnection To: Nicolas Saenz Julienne , Oliver Neukum , Mathias Nyman Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org References: <20190318170038.23914-1-nsaenzjulienne@suse.de> <1552993288.14757.23.camel@suse.com> <82718bec37e4e16e0a08b3b7a00452f99adc707b.camel@suse.de> From: Mathias Nyman Message-ID: Date: Wed, 20 Mar 2019 15:55:02 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <82718bec37e4e16e0a08b3b7a00452f99adc707b.camel@suse.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19.3.2019 16.54, Nicolas Saenz Julienne wrote: > Hi Oliver, thanks for the review! > > On Tue, 2019-03-19 at 12:01 +0100, Oliver Neukum wrote: >> On Mo, 2019-03-18 at 18:00 +0100, Nicolas Saenz Julienne wrote: >>> This patch clears "port_remote_wakeup" upon detecting a device >>> disconnection. Making sure the above mentioned situation doesn't trigger >>> a PM busyloop. >> >> Hi, >> >> that is an interesting race condition. >> Turns out that port_remote_wakeup was only properly cleared in case of a successful resume where port stays in U0, or in case of an error where port goes to inactive state. In all other cases port_remote_wakeup bit was left uncleared. >>> Signed-off-by: Nicolas Saenz Julienne >>> --- >>> drivers/usb/host/xhci-hub.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c >>> index e2eece693655..bea853f45aec 100644 >>> --- a/drivers/usb/host/xhci-hub.c >>> +++ b/drivers/usb/host/xhci-hub.c >>> @@ -942,6 +942,9 @@ static void xhci_get_usb3_port_status(struct xhci_port >>> *port, u32 *status, >>> bus_state->suspended_ports &= ~(1 << portnum); >>> } >>> >>> + if (!(portsc & PORT_CONNECT)) >>> + bus_state->port_remote_wakeup &= ~(1 << portnum); >>> + A check like this should cover the failing resume cases, thanks We also saw a case when a successful resume was missed as port went into U1 Link power save state (resume->U0->U1) before xhci driver read the port status. A patch adding U1 and U2 to successful resume states is pending in my for-usb-linus branch for this. >> >> Why are you putting that logic into xhci_get_usb3_port_status()? >> It looks to me like there is already something related in the caller > > You're right, xhci_get_usb3_port_status() is not the ideal spot I'll move the > code there. > Sounds good, thanks -Mathias