Return-path: Received: from out4-smtp.messagingengine.com ([66.111.4.28]:35521 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751073AbdBJEVB (ORCPT ); Thu, 9 Feb 2017 23:21:01 -0500 Date: Thu, 9 Feb 2017 21:20:55 -0700 From: Mark Greer To: Geoff Lansberry Cc: Mark Greer , linux-wireless , Lauro Ramos Venancio , Aloisio Almeida Jr , Samuel Ortiz , Justin Bronder , linux-nfc , Jaret Cantu Subject: Re: [Patch] NFC: trf7970a: Message-ID: <20170210042055.GA9104@animalcreek.com> (sfid-20170210_052107_258342_61C47201) References: <20161214223123.GA10281@animalcreek.com> <20161216045210.GA29196@animalcreek.com> <20161216203538.GA12608@animalcreek.com> <20161219030733.GA14962@animalcreek.com> <20170208225339.GA26286@animalcreek.com> <20170208225651.GB26286@animalcreek.com> <20170209212706.GA26734@animalcreek.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Feb 09, 2017 at 07:41:11PM -0500, Geoff Lansberry wrote: > On Thu, Feb 9, 2017 at 4:27 PM, Mark Greer wrote: > > > > On Thu, Feb 09, 2017 at 10:54:08AM -0500, Geoff Lansberry wrote: > > > On Wed, Feb 8, 2017 at 5:56 PM, Mark Greer wrote: > > > > > > > > I just realized that the linux-nfc is not CC'd so adding it. > > > > > > > > On Wed, Feb 08, 2017 at 03:53:39PM -0700, Mark Greer wrote: > > > > > On Sun, Dec 18, 2016 at 08:07:33PM -0700, Mark Greer wrote: > > > > > > On Sat, Dec 17, 2016 at 04:19:04PM -0500, Geoff Lansberry wrote: > > > > > > > Mark, from our consultant: > > > > > > > > > > > > > > It isn't important whether the flood script is successful in writing > > > > > > > or not. The point of it is to force a segfault by making many > > > > > > > requests. It needs to run for several hundred iterations (successful > > > > > > > or not) in order to generate the segfault. > > > > > > > > > > > > So neard crashes even when the write fails?? Okay, I'll let it run for > > > > > > a while tomorrow (Monday). > > > > > > > > > > [Okay, so not exactly "tomorrow" but I did get back to this.] > > > > > > > > > > Geoff, a few things: > > > > > > > > > > 1) Any update on these issues? > > > > > > Yes - I've discovered the primary trigger of my problems. I'm using > > > some very small tags from Murata, and they don't have a strong signal. > > > Sometimes when writing, the tags can get corrupted data written to > > > them. When the tag is verified by re-reading it, neard bails out > > > because it finds non-utf8 characters. So far I have found it > > > impossible to rewrite a tag once it has been mal-formed. > > > > Okay, that's interesting. neard still shouldn't bail out so we'll > > have to look at that. > > This is the most critical thing for us right now. Can you make a > malformed tag and try it to see if you have the same issue? What I > typically see is 0xFE character too early in the string, or similarly > the length being too long for the string. If you can do that, then > try to write or read it via neard. If you can confirm the quitting > behavior, that will help a lot. I can live with the corruption, > because I can detect it and re-write if it happens. I don't have such a thing but I can always hack something to write bogus data. I may not get to this until next week, though. > > > > > 2) Do you have all of the NFC-related patches from the nfc-next master > > > > > branch? In particular, do you have all of Thierry's patches to > > > > > net/nfc/digial_*.c dated around June-July 2016? Without those patches, > > > > > I see a panic; with them, I don't. > > > > > > No, we don't. the last patch I've got in our kernel version is yours > > > from 7-21-2014. I'm inquiring with more experienced people to see how > > > to address that. > > > > Oh... Then you really need to update. Look at the master branch in the > > nfc-next repo (git://git.kernel.org/pub/scm/linux/kernel/git/sameo/nfc-next.git) > > Those commits are in the latest ti build, > https://git.ti.com/ti-linux-kernel/ti-linux-kernel/commits/ti-linux-4.9.y, > so I've built that up. Yes, v4.9.y has everything so that's a good one to work from. > Unfortunately bricked the board and don't > have the dev tools to fix it with me. Bummer, should be back into it > tomorrow. :(