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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 80880C5478C for ; Mon, 4 Mar 2024 15:11:31 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rh9xn-0007Ys-Kt; Mon, 04 Mar 2024 10:10:47 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rh9xl-0007Y9-T4; Mon, 04 Mar 2024 10:10:45 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rh9xj-0002kY-UH; Mon, 04 Mar 2024 10:10:45 -0500 Received: from mail.maildlp.com (unknown [172.18.186.31]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4TpMVD2GL1z6K9QK; Mon, 4 Mar 2024 23:06:44 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (unknown [7.191.163.240]) by mail.maildlp.com (Postfix) with ESMTPS id D1C4F140516; Mon, 4 Mar 2024 23:10:38 +0800 (CST) Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Mon, 4 Mar 2024 15:10:38 +0000 Date: Mon, 4 Mar 2024 15:10:37 +0000 To: Thomas Huth CC: , Fan Ni , "Michael S. Tsirkin" , Marcel Apfelbaum , Subject: Re: [PATCH 3/3] hw/mem/cxl_type3: Fix problem with g_steal_pointer() Message-ID: <20240304151037.00000f6c@Huawei.com> In-Reply-To: <20240304104406.59855-4-thuth@redhat.com> References: <20240304104406.59855-1-thuth@redhat.com> <20240304104406.59855-4-thuth@redhat.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.76] X-ClientProxiedBy: lhrpeml100004.china.huawei.com (7.191.162.219) To lhrpeml500005.china.huawei.com (7.191.163.240) Received-SPF: pass client-ip=185.176.79.56; envelope-from=jonathan.cameron@huawei.com; helo=frasgout.his.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-to: Jonathan Cameron From: Jonathan Cameron via Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, 4 Mar 2024 11:44:06 +0100 Thomas Huth wrote: > When setting GLIB_VERSION_MAX_ALLOWED to GLIB_VERSION_2_58 or higher, > glib adds type safety checks to the g_steal_pointer() macro. This > triggers errors in the ct3_build_cdat_entries_for_mr() function which > uses the g_steal_pointer() for type-casting from one pointer type to > the other (which also looks quite weird since the local pointers have > all been declared with g_autofree though they are never freed here). > Fix it by using a proper typecast instead. For making this possible, we > have to remove the QEMU_PACKED attribute from some structs since GCC > otherwise complains that the source and destination pointer might > have different alignment restrictions. Removing the QEMU_PACKED should > be fine here since the structs are already naturally aligned. Anyway, > add some QEMU_BUILD_BUG_ON() statements to make sure that we've got > the right sizes (without padding in the structs). I missed these as well when getting rid of the false handling of failure of g_new0 calls. Another alternative would be to point to the head structures rather than the containing structure - would avoid need to cast. That might be neater? Should I think also remove the alignment question? > > Signed-off-by: Thomas Huth > --- > include/hw/cxl/cxl_cdat.h | 9 ++++++--- > hw/mem/cxl_type3.c | 24 ++++++++++++------------ > 2 files changed, 18 insertions(+), 15 deletions(-) > > diff --git a/include/hw/cxl/cxl_cdat.h b/include/hw/cxl/cxl_cdat.h > index b44cefaad6..17a09066dc 100644 > --- a/include/hw/cxl/cxl_cdat.h > +++ b/include/hw/cxl/cxl_cdat.h > @@ -82,7 +82,8 @@ typedef struct CDATDsmas { > uint16_t reserved; > uint64_t DPA_base; > uint64_t DPA_length; > -} QEMU_PACKED CDATDsmas; > +} CDATDsmas; > +QEMU_BUILD_BUG_ON(sizeof(CDATDsmas) != 24); > > /* Device Scoped Latency and Bandwidth Information Structure - CDAT Table 5 */ > typedef struct CDATDslbis { > @@ -95,7 +96,8 @@ typedef struct CDATDslbis { > uint64_t entry_base_unit; > uint16_t entry[3]; > uint16_t reserved2; > -} QEMU_PACKED CDATDslbis; > +} CDATDslbis; > +QEMU_BUILD_BUG_ON(sizeof(CDATDslbis) != 24); > > /* Device Scoped Memory Side Cache Information Structure - CDAT Table 6 */ > typedef struct CDATDsmscis { > @@ -122,7 +124,8 @@ typedef struct CDATDsemts { > uint16_t reserved; > uint64_t DPA_offset; > uint64_t DPA_length; > -} QEMU_PACKED CDATDsemts; > +} CDATDsemts; > +QEMU_BUILD_BUG_ON(sizeof(CDATDsemts) != 24); > > /* Switch Scoped Latency and Bandwidth Information Structure - CDAT Table 9 */ > typedef struct CDATSslbisHeader { > diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c > index e8801805b9..b679dfae1c 100644 > --- a/hw/mem/cxl_type3.c > +++ b/hw/mem/cxl_type3.c > @@ -46,12 +46,12 @@ static void ct3_build_cdat_entries_for_mr(CDATSubHeader **cdat_table, > int dsmad_handle, MemoryRegion *mr, > bool is_pmem, uint64_t dpa_base) > { > - g_autofree CDATDsmas *dsmas = NULL; > - g_autofree CDATDslbis *dslbis0 = NULL; > - g_autofree CDATDslbis *dslbis1 = NULL; > - g_autofree CDATDslbis *dslbis2 = NULL; > - g_autofree CDATDslbis *dslbis3 = NULL; > - g_autofree CDATDsemts *dsemts = NULL; > + CDATDsmas *dsmas; > + CDATDslbis *dslbis0; > + CDATDslbis *dslbis1; > + CDATDslbis *dslbis2; > + CDATDslbis *dslbis3; > + CDATDsemts *dsemts; > > dsmas = g_malloc(sizeof(*dsmas)); > *dsmas = (CDATDsmas) { > @@ -135,12 +135,12 @@ static void ct3_build_cdat_entries_for_mr(CDATSubHeader **cdat_table, > }; > > /* Header always at start of structure */ > - cdat_table[CT3_CDAT_DSMAS] = g_steal_pointer(&dsmas); > - cdat_table[CT3_CDAT_DSLBIS0] = g_steal_pointer(&dslbis0); > - cdat_table[CT3_CDAT_DSLBIS1] = g_steal_pointer(&dslbis1); > - cdat_table[CT3_CDAT_DSLBIS2] = g_steal_pointer(&dslbis2); > - cdat_table[CT3_CDAT_DSLBIS3] = g_steal_pointer(&dslbis3); > - cdat_table[CT3_CDAT_DSEMTS] = g_steal_pointer(&dsemts); > + cdat_table[CT3_CDAT_DSMAS] = (CDATSubHeader *)dsmas; Could do cdat_table[CT3_CDAT_DSMAS] = &dsmas->header; etc > + cdat_table[CT3_CDAT_DSLBIS0] = (CDATSubHeader *)dslbis0; > + cdat_table[CT3_CDAT_DSLBIS1] = (CDATSubHeader *)dslbis1; > + cdat_table[CT3_CDAT_DSLBIS2] = (CDATSubHeader *)dslbis2; > + cdat_table[CT3_CDAT_DSLBIS3] = (CDATSubHeader *)dslbis3; > + cdat_table[CT3_CDAT_DSEMTS] = (CDATSubHeader *)dsemts; > } > > static int ct3_build_cdat_table(CDATSubHeader ***cdat_table, void *priv)