From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2FC9863D; Tue, 28 Jun 2022 10:37:20 +0000 (UTC) Received: from fraeml707-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4LXLcL55CRz687rC; Tue, 28 Jun 2022 18:36:34 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml707-chm.china.huawei.com (10.206.15.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 28 Jun 2022 12:37:17 +0200 Received: from localhost (10.202.226.42) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 28 Jun 2022 11:37:16 +0100 Date: Tue, 28 Jun 2022 11:37:15 +0100 From: Jonathan Cameron To: Dan Williams CC: , , , , , Subject: Re: [PATCH 01/46] tools/testing/cxl: Fix cxl_hdm_decode_init() calling convention Message-ID: <20220628113715.00005857@Huawei.com> In-Reply-To: <165603870776.551046.8709990108936497723.stgit@dwillia2-xfh> References: <165603869943.551046.3498980330327696732.stgit@dwillia2-xfh> <165603870776.551046.8709990108936497723.stgit@dwillia2-xfh> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.29; i686-w64-mingw32) Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.226.42] X-ClientProxiedBy: lhreml712-chm.china.huawei.com (10.201.108.63) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected On Thu, 23 Jun 2022 19:45:07 -0700 Dan Williams wrote: > This failing signature: > > [ 8.392669] cxl_bus_probe: cxl_port endpoint2: probe: 970997760 > [ 8.392670] cxl_port: probe of endpoint2 failed with error 970997760 > [ 8.392719] create_endpoint: cxl_mem mem0: add: endpoint2 > [ 8.392721] cxl_mem mem0: endpoint2 failed probe > [ 8.392725] cxl_bus_probe: cxl_mem mem0: probe: -6 > > ...shows cxl_hdm_decode_init() resulting in a return code ("970997760") > that looks like stack corruption. The problem goes away if > cxl_hdm_decode_init() is not mocked via __wrap_cxl_hdm_decode_init(). > > The corruption results from the mismatch that the calling convention for > cxl_hdm_decode_init() is: > > int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm) > > ...and __wrap_cxl_hdm_decode_init() is: > > bool __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm) > > ...i.e. an int is expected but __wrap_hdm_decode_init() returns bool. > > Fix the convention and cleanup the organization to match > __wrap_cxl_await_media_ready() as the difference was a red herring that > distracted from finding the bug. > > Fixes: 92804edb11f0 ("cxl/pci: Drop @info argument to cxl_hdm_decode_init()") > Signed-off-by: Dan Williams LGTM Reviewed-by: Jonathan Cameron > --- > tools/testing/cxl/test/mock.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/tools/testing/cxl/test/mock.c b/tools/testing/cxl/test/mock.c > index f1f8c40948c5..bce6a21df0d5 100644 > --- a/tools/testing/cxl/test/mock.c > +++ b/tools/testing/cxl/test/mock.c > @@ -208,13 +208,15 @@ int __wrap_cxl_await_media_ready(struct cxl_dev_state *cxlds) > } > EXPORT_SYMBOL_NS_GPL(__wrap_cxl_await_media_ready, CXL); > > -bool __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds, > - struct cxl_hdm *cxlhdm) > +int __wrap_cxl_hdm_decode_init(struct cxl_dev_state *cxlds, > + struct cxl_hdm *cxlhdm) > { > int rc = 0, index; > struct cxl_mock_ops *ops = get_cxl_mock_ops(&index); > > - if (!ops || !ops->is_mock_dev(cxlds->dev)) > + if (ops && ops->is_mock_dev(cxlds->dev)) > + rc = 0; > + else > rc = cxl_hdm_decode_init(cxlds, cxlhdm); > put_cxl_mock_ops(index); > >