[{"id":1760634,"web_url":"http://patchwork.ozlabs.org/comment/1760634/","msgid":"<87fuc8js5v.fsf@linux.vnet.ibm.com>","list_archive_url":null,"date":"2017-08-31T04:08:12","subject":"Re: [Skiboot] [PATCH] p8-i2c: Fix random data corruption","submitter":{"id":48041,"url":"http://patchwork.ozlabs.org/api/people/48041/","name":"Stewart Smith","email":"stewart@linux.vnet.ibm.com"},"content":"Oliver O'Halloran writes:\n> While waiting for the OCC to signal that it has finished using the I2C\n> master we put the master into the, poorly named, occache_dis state.\n> While in this state the transaction hasn't been started, but\n> p8_i2c_check_status() will only skip it's checks when the master is in\n> the idle state. Any action that checks that cranks the I2C state machine\n> (interrupt, poll, etc) will call p8_i2c_check_status() and since the\n> master is not idle, it will check the status register, see the\n> transaction complete flag set and complete the i2c request without\n> actually doing anything.\n>\n> If the transaction was a I2C read, the resulting output will be a\n> zeroed data buffer.\n>\n> Signed-off-by: Oliver O'Halloran \n\nAren't state machines fun! Merged in as\nb73d15fa328ee242102dce4f7cda1cc650c787aa","headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","skiboot@lists.ozlabs.org"],"Delivered-To":["patchwork-incoming@bilbo.ozlabs.org","skiboot@lists.ozlabs.org"],"Received":["from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\t(using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xjTPm4mdcz9s71\n\tfor ;\n\tThu, 31 Aug 2017 14:08:28 +1000 (AEST)","from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\tby lists.ozlabs.org (Postfix) with ESMTP id 3xjTPm3mDnzDqSb\n\tfor ;\n\tThu, 31 Aug 2017 14:08:28 +1000 (AEST)","from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com\n\t[148.163.156.1])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256\n\tbits)) (No client certificate requested)\n\tby lists.ozlabs.org (Postfix) with ESMTPS id 3xjTPc4W8MzDq5k\n\tfor ; Thu, 31 Aug 2017 14:08:20 +1000 (AEST)","from pps.filterd (m0098393.ppops.net [127.0.0.1])\n\tby mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id\n\tv7V467S9110037\n\tfor ; Thu, 31 Aug 2017 00:08:18 -0400","from e17.ny.us.ibm.com (e17.ny.us.ibm.com [129.33.205.207])\n\tby mx0a-001b2d01.pphosted.com with ESMTP id 2cpa7cbea2-1\n\t(version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT)\n\tfor ; Thu, 31 Aug 2017 00:08:18 -0400","from localhost\n\tby e17.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use\n\tOnly! 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Violators will be prosecuted; \n\tThu, 31 Aug 2017 00:08:15 -0400","from b01ledav001.gho.pok.ibm.com (b01ledav001.gho.pok.ibm.com\n\t[9.57.199.106])\n\tby b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP\n\tid v7V48Fr829622322; Thu, 31 Aug 2017 04:08:15 GMT","from b01ledav001.gho.pok.ibm.com (unknown [127.0.0.1])\n\tby IMSVA (Postfix) with ESMTP id B6CF928046;\n\tThu, 31 Aug 2017 00:08:08 -0400 (EDT)","from birb.localdomain (unknown [9.81.216.230])\n\tby b01ledav001.gho.pok.ibm.com (Postfix) with SMTP id ED9452803E;\n\tThu, 31 Aug 2017 00:08:07 -0400 (EDT)","by birb.localdomain (Postfix, from userid 1000)\n\tid A61454E87E6; Thu, 31 Aug 2017 14:08:12 +1000 (AEST)"],"From":"Stewart Smith ","To":"\"Oliver O'Halloran\" , skiboot@lists.ozlabs.org","In-Reply-To":"<20170830123606.8490-1-oohall@gmail.com>","References":"<20170830123606.8490-1-oohall@gmail.com>","Date":"Thu, 31 Aug 2017 14:08:12 +1000","MIME-Version":"1.0","X-TM-AS-GCONF":"00","x-cbid":"17083104-0040-0000-0000-0000039837B9","X-IBM-SpamModules-Scores":"","X-IBM-SpamModules-Versions":"BY=3.00007639; HX=3.00000241; KW=3.00000007;\n\tPH=3.00000004; SC=3.00000226; SDB=6.00910032; UDB=6.00456471;\n\tIPR=6.00690312; \n\tBA=6.00005562; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009;\n\tZB=6.00000000; \n\tZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00016938;\n\tXFM=3.00000015; UTC=2017-08-31 04:08:17","X-IBM-AV-DETECTION":"SAVI=unused REMOTE=unused XFE=unused","x-cbparentid":"17083104-0041-0000-0000-0000078C69C2","Message-Id":"<87fuc8js5v.fsf@linux.vnet.ibm.com>","X-Proofpoint-Virus-Version":"vendor=fsecure engine=2.50.10432:, ,\n\tdefinitions=2017-08-30_10:, , signatures=0","X-Proofpoint-Spam-Details":"rule=outbound_notspam policy=outbound score=0\n\tspamscore=0 suspectscore=1\n\tmalwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam\n\tadjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000\n\tdefinitions=main-1708310060","Subject":"Re: [Skiboot] [PATCH] p8-i2c: Fix random data corruption","X-BeenThere":"skiboot@lists.ozlabs.org","X-Mailman-Version":"2.1.23","Precedence":"list","List-Id":"Mailing list for skiboot development ","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Content-Type":"text/plain; charset=\"utf-8\"","Content-Transfer-Encoding":"base64","Errors-To":"skiboot-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org","Sender":"\"Skiboot\"\n\t"}}]