From patchwork Mon Jul 12 12:57:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12371061 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=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 29D21C07E99 for ; Mon, 12 Jul 2021 12:57:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12910610CD for ; Mon, 12 Jul 2021 12:57:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234302AbhGLNAX (ORCPT ); Mon, 12 Jul 2021 09:00:23 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:22469 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234277AbhGLNAX (ORCPT ); Mon, 12 Jul 2021 09:00:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626094654; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pijkkFunK/KgSE5Hnt3DYoUXA+GaOYkeh4OG3XXbBpI=; b=PgusRj7FM+UnWhZtQPblD+nI466NZ862Gx4QNpnw0D49NN4eIM01YmLjuy805Jn6+7TQZs pAU32exP/ZEPZW7Hq5c3o5FEgmvX/h4OvtxmxsYF+dw8Z0x4OK6/WNNpAWuuXuxKc07q3n G908vDm/wLsyZ3L80EIeH+LGLbzhkio= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-575-catWmAfCNUins8md4jB1sA-1; Mon, 12 Jul 2021 08:57:31 -0400 X-MC-Unique: catWmAfCNUins8md4jB1sA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E7EF781CCC0; Mon, 12 Jul 2021 12:57:21 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-118-19.rdu2.redhat.com [10.10.118.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5F9E4369A; Mon, 12 Jul 2021 12:57:20 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 1/3] afs: Fix tracepoint string placement with built-in AFS From: David Howells To: linux-afs@lists.infradead.org Cc: "Alexey Dobriyan (SK hynix)" , "Steven Rostedt (VMware)" , Andrew Morton , dhowells@redhat.com, Marc Dionne , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 12 Jul 2021 13:57:19 +0100 Message-ID: <162609463957.3133237.15916579353149746363.stgit@warthog.procyon.org.uk> In-Reply-To: <162609463116.3133237.11899334298425929820.stgit@warthog.procyon.org.uk> References: <162609463116.3133237.11899334298425929820.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org To quote Alexey[1]: I was adding custom tracepoint to the kernel, grabbed full F34 kernel .config, disabled modules and booted whole shebang as VM kernel. Then did perf record -a -e ... It crashed: general protection fault, probably for non-canonical address 0x435f5346592e4243: 0000 [#1] SMP PTI CPU: 1 PID: 842 Comm: cat Not tainted 5.12.6+ #26 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014 RIP: 0010:t_show+0x22/0xd0 Then reproducer was narrowed to # cat /sys/kernel/tracing/printk_formats Original F34 kernel with modules didn't crash. So I started to disable options and after disabling AFS everything started working again. The root cause is that AFS was placing char arrays content into a section full of _pointers_ to strings with predictable consequences. Non canonical address 435f5346592e4243 is "CB.YFS_" which came from CM_NAME macro. Steps to reproduce: CONFIG_AFS=y CONFIG_TRACING=y # cat /sys/kernel/tracing/printk_formats Fix this by the following means: (1) Add enum->string translation tables in the event header with the AFS and YFS cache/callback manager operations listed by RPC operation ID. (2) Modify the afs_cb_call tracepoint to print the string from the translation table rather than using the string at the afs_call name pointer. (3) Switch translation table depending on the service we're being accessed as (AFS or YFS) in the tracepoint print clause. Will this cause problems to userspace utilities? Note that the symbolic representation of the YFS service ID isn't available to this header, so I've put it in as a number. I'm not sure if this is the best way to do this. (4) Remove the name wrangling (CM_NAME) macro and put the names directly into the afs_call_type structs in cmservice.c. Fixes: 8e8d7f13b6d5a9 ("afs: Add some tracepoints") Reported-by: Alexey Dobriyan (SK hynix) Signed-off-by: David Howells Reviewed-by: Steven Rostedt (VMware) cc: Andrew Morton cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/YLAXfvZ+rObEOdc%2F@localhost.localdomain/ [1] Link: https://lore.kernel.org/r/643721.1623754699@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/162430903582.2896199.6098150063997983353.stgit@warthog.procyon.org.uk/ # v1 --- fs/afs/cmservice.c | 25 +++++----------- include/trace/events/afs.h | 67 +++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 69 insertions(+), 23 deletions(-) diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c index d3c6bb22c5f4..a3f5de28be79 100644 --- a/fs/afs/cmservice.c +++ b/fs/afs/cmservice.c @@ -29,16 +29,11 @@ static void SRXAFSCB_TellMeAboutYourself(struct work_struct *); static int afs_deliver_yfs_cb_callback(struct afs_call *); -#define CM_NAME(name) \ - char afs_SRXCB##name##_name[] __tracepoint_string = \ - "CB." #name - /* * CB.CallBack operation type */ -static CM_NAME(CallBack); static const struct afs_call_type afs_SRXCBCallBack = { - .name = afs_SRXCBCallBack_name, + .name = "CB.CallBack", .deliver = afs_deliver_cb_callback, .destructor = afs_cm_destructor, .work = SRXAFSCB_CallBack, @@ -47,9 +42,8 @@ static const struct afs_call_type afs_SRXCBCallBack = { /* * CB.InitCallBackState operation type */ -static CM_NAME(InitCallBackState); static const struct afs_call_type afs_SRXCBInitCallBackState = { - .name = afs_SRXCBInitCallBackState_name, + .name = "CB.InitCallBackState", .deliver = afs_deliver_cb_init_call_back_state, .destructor = afs_cm_destructor, .work = SRXAFSCB_InitCallBackState, @@ -58,9 +52,8 @@ static const struct afs_call_type afs_SRXCBInitCallBackState = { /* * CB.InitCallBackState3 operation type */ -static CM_NAME(InitCallBackState3); static const struct afs_call_type afs_SRXCBInitCallBackState3 = { - .name = afs_SRXCBInitCallBackState3_name, + .name = "CB.InitCallBackState3", .deliver = afs_deliver_cb_init_call_back_state3, .destructor = afs_cm_destructor, .work = SRXAFSCB_InitCallBackState, @@ -69,9 +62,8 @@ static const struct afs_call_type afs_SRXCBInitCallBackState3 = { /* * CB.Probe operation type */ -static CM_NAME(Probe); static const struct afs_call_type afs_SRXCBProbe = { - .name = afs_SRXCBProbe_name, + .name = "CB.Probe", .deliver = afs_deliver_cb_probe, .destructor = afs_cm_destructor, .work = SRXAFSCB_Probe, @@ -80,9 +72,8 @@ static const struct afs_call_type afs_SRXCBProbe = { /* * CB.ProbeUuid operation type */ -static CM_NAME(ProbeUuid); static const struct afs_call_type afs_SRXCBProbeUuid = { - .name = afs_SRXCBProbeUuid_name, + .name = "CB.ProbeUuid", .deliver = afs_deliver_cb_probe_uuid, .destructor = afs_cm_destructor, .work = SRXAFSCB_ProbeUuid, @@ -91,9 +82,8 @@ static const struct afs_call_type afs_SRXCBProbeUuid = { /* * CB.TellMeAboutYourself operation type */ -static CM_NAME(TellMeAboutYourself); static const struct afs_call_type afs_SRXCBTellMeAboutYourself = { - .name = afs_SRXCBTellMeAboutYourself_name, + .name = "CB.TellMeAboutYourself", .deliver = afs_deliver_cb_tell_me_about_yourself, .destructor = afs_cm_destructor, .work = SRXAFSCB_TellMeAboutYourself, @@ -102,9 +92,8 @@ static const struct afs_call_type afs_SRXCBTellMeAboutYourself = { /* * YFS CB.CallBack operation type */ -static CM_NAME(YFS_CallBack); static const struct afs_call_type afs_SRXYFSCB_CallBack = { - .name = afs_SRXCBYFS_CallBack_name, + .name = "YFSCB.CallBack", .deliver = afs_deliver_yfs_cb_callback, .destructor = afs_cm_destructor, .work = SRXAFSCB_CallBack, diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h index 3ccf591b2374..9f73ed2cf061 100644 --- a/include/trace/events/afs.h +++ b/include/trace/events/afs.h @@ -174,6 +174,34 @@ enum afs_vl_operation { afs_VL_GetCapabilities = 65537, /* AFS Get VL server capabilities */ }; +enum afs_cm_operation { + afs_CB_CallBack = 204, /* AFS break callback promises */ + afs_CB_InitCallBackState = 205, /* AFS initialise callback state */ + afs_CB_Probe = 206, /* AFS probe client */ + afs_CB_GetLock = 207, /* AFS get contents of CM lock table */ + afs_CB_GetCE = 208, /* AFS get cache file description */ + afs_CB_GetXStatsVersion = 209, /* AFS get version of extended statistics */ + afs_CB_GetXStats = 210, /* AFS get contents of extended statistics data */ + afs_CB_InitCallBackState3 = 213, /* AFS initialise callback state, version 3 */ + afs_CB_ProbeUuid = 214, /* AFS check the client hasn't rebooted */ +}; + +enum yfs_cm_operation { + yfs_CB_Probe = 206, /* YFS probe client */ + yfs_CB_GetLock = 207, /* YFS get contents of CM lock table */ + yfs_CB_XStatsVersion = 209, /* YFS get version of extended statistics */ + yfs_CB_GetXStats = 210, /* YFS get contents of extended statistics data */ + yfs_CB_InitCallBackState3 = 213, /* YFS initialise callback state, version 3 */ + yfs_CB_ProbeUuid = 214, /* YFS check the client hasn't rebooted */ + yfs_CB_GetServerPrefs = 215, + yfs_CB_GetCellServDV = 216, + yfs_CB_GetLocalCell = 217, + yfs_CB_GetCacheConfig = 218, + yfs_CB_GetCellByNum = 65537, + yfs_CB_TellMeAboutYourself = 65538, /* get client capabilities */ + yfs_CB_CallBack = 64204, +}; + enum afs_edit_dir_op { afs_edit_dir_create, afs_edit_dir_create_error, @@ -436,6 +464,32 @@ enum afs_cb_break_reason { EM(afs_YFSVL_GetCellName, "YFSVL.GetCellName") \ E_(afs_VL_GetCapabilities, "VL.GetCapabilities") +#define afs_cm_operations \ + EM(afs_CB_CallBack, "CB.CallBack") \ + EM(afs_CB_InitCallBackState, "CB.InitCallBackState") \ + EM(afs_CB_Probe, "CB.Probe") \ + EM(afs_CB_GetLock, "CB.GetLock") \ + EM(afs_CB_GetCE, "CB.GetCE") \ + EM(afs_CB_GetXStatsVersion, "CB.GetXStatsVersion") \ + EM(afs_CB_GetXStats, "CB.GetXStats") \ + EM(afs_CB_InitCallBackState3, "CB.InitCallBackState3") \ + E_(afs_CB_ProbeUuid, "CB.ProbeUuid") + +#define yfs_cm_operations \ + EM(yfs_CB_Probe, "YFSCB.Probe") \ + EM(yfs_CB_GetLock, "YFSCB.GetLock") \ + EM(yfs_CB_XStatsVersion, "YFSCB.XStatsVersion") \ + EM(yfs_CB_GetXStats, "YFSCB.GetXStats") \ + EM(yfs_CB_InitCallBackState3, "YFSCB.InitCallBackState3") \ + EM(yfs_CB_ProbeUuid, "YFSCB.ProbeUuid") \ + EM(yfs_CB_GetServerPrefs, "YFSCB.GetServerPrefs") \ + EM(yfs_CB_GetCellServDV, "YFSCB.GetCellServDV") \ + EM(yfs_CB_GetLocalCell, "YFSCB.GetLocalCell") \ + EM(yfs_CB_GetCacheConfig, "YFSCB.GetCacheConfig") \ + EM(yfs_CB_GetCellByNum, "YFSCB.GetCellByNum") \ + EM(yfs_CB_TellMeAboutYourself, "YFSCB.TellMeAboutYourself") \ + E_(yfs_CB_CallBack, "YFSCB.CallBack") + #define afs_edit_dir_ops \ EM(afs_edit_dir_create, "create") \ EM(afs_edit_dir_create_error, "c_fail") \ @@ -569,6 +623,8 @@ afs_server_traces; afs_cell_traces; afs_fs_operations; afs_vl_operations; +afs_cm_operations; +yfs_cm_operations; afs_edit_dir_ops; afs_edit_dir_reasons; afs_eproto_causes; @@ -649,20 +705,21 @@ TRACE_EVENT(afs_cb_call, TP_STRUCT__entry( __field(unsigned int, call ) - __field(const char *, name ) __field(u32, op ) + __field(u16, service_id ) ), TP_fast_assign( __entry->call = call->debug_id; - __entry->name = call->type->name; __entry->op = call->operation_ID; + __entry->service_id = call->service_id; ), - TP_printk("c=%08x %s o=%u", + TP_printk("c=%08x %s", __entry->call, - __entry->name, - __entry->op) + __entry->service_id == 2501 ? + __print_symbolic(__entry->op, yfs_cm_operations) : + __print_symbolic(__entry->op, afs_cm_operations)) ); TRACE_EVENT(afs_call, From patchwork Mon Jul 12 12:57:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12371059 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=-16.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 11C8FC07E99 for ; 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 2/3] afs: check function return From: David Howells To: linux-afs@lists.infradead.org Cc: Tom Rix , dhowells@redhat.com, Marc Dionne , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 12 Jul 2021 13:57:27 +0100 Message-ID: <162609464716.3133237.10354897554363093252.stgit@warthog.procyon.org.uk> In-Reply-To: <162609463116.3133237.11899334298425929820.stgit@warthog.procyon.org.uk> References: <162609463116.3133237.11899334298425929820.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Tom Rix Static analysis reports this problem write.c:773:29: warning: Assigned value is garbage or undefined mapping->writeback_index = next; ^ ~~~~ The call to afs_writepages_region() can return without setting next. So check the function return before using next. Fixes: e87b03f5830e ("afs: Prepare for use of THPs") Signed-off-by: Tom Rix Signed-off-by: David Howells Link: https://lore.kernel.org/r/20210430155031.3287870-1-trix@redhat.com --- fs/afs/write.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/afs/write.c b/fs/afs/write.c index 3104b62c2082..2794147f82ff 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -777,7 +777,7 @@ int afs_writepages(struct address_space *mapping, mapping->writeback_index = next / PAGE_SIZE; } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) { ret = afs_writepages_region(mapping, wbc, 0, LLONG_MAX, &next); - if (wbc->nr_to_write > 0) + if (wbc->nr_to_write > 0 && ret == 0) mapping->writeback_index = next; } else { ret = afs_writepages_region(mapping, wbc, From patchwork Mon Jul 12 12:57:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 12371063 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=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 A2240C07E99 for ; Mon, 12 Jul 2021 12:57:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 87DAF610CD for ; Mon, 12 Jul 2021 12:57:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234370AbhGLNAa (ORCPT ); Mon, 12 Jul 2021 09:00:30 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:46500 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234334AbhGLNAa (ORCPT ); Mon, 12 Jul 2021 09:00:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626094661; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=61t+gIjESYmgaXgLkp+R0buthxKeNg7bBJsRPr9kTTw=; b=fumKmtfSLVzbgQ58f3Jimw0O5YWmiRuQW0YelpGUridx3hiBLVqS2WxqbVNlQ/xo6OQiMp ugXXzpD2kDzzCymWL3ExJZTHt+7QobKKc/7eeRxMnlETg00zBPMwzTsq6J45dnz+N/Otjh vFy6CMOiLZH24+iLEoWbXC6TBawf44I= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-216-bzPbo1d_PpmdhLNtvGW5EA-1; Mon, 12 Jul 2021 08:57:37 -0400 X-MC-Unique: bzPbo1d_PpmdhLNtvGW5EA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 84BD5801107; Mon, 12 Jul 2021 12:57:36 +0000 (UTC) Received: from warthog.procyon.org.uk (ovpn-118-19.rdu2.redhat.com [10.10.118.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3DCA85C1D1; Mon, 12 Jul 2021 12:57:35 +0000 (UTC) Organization: Red Hat UK Ltd. 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Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 3/3] afs: Remove redundant assignment to ret From: David Howells To: linux-afs@lists.infradead.org Cc: Abaci Robot , Jiapeng Chong , dhowells@redhat.com, Marc Dionne , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 12 Jul 2021 13:57:34 +0100 Message-ID: <162609465444.3133237.7562832521724298900.stgit@warthog.procyon.org.uk> In-Reply-To: <162609463116.3133237.11899334298425929820.stgit@warthog.procyon.org.uk> References: <162609463116.3133237.11899334298425929820.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.23 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Jiapeng Chong Variable ret is set to -ENOENT and -ENOMEM but this value is never read as it is overwritten or not used later on, hence it is a redundant assignment and can be removed. Cleans up the following clang-analyzer warning: fs/afs/dir.c:2014:4: warning: Value stored to 'ret' is never read [clang-analyzer-deadcode.DeadStores]. fs/afs/dir.c:659:2: warning: Value stored to 'ret' is never read [clang-analyzer-deadcode.DeadStores]. [DH made the following modifications: - In afs_rename(), -ENOMEM should be placed in op->error instead of ret, rather than the assignment being removed entirely. afs_put_operation() will pick it up from there and return it. - If afs_sillyrename() fails, its error code should be placed in op->error rather than in ret also. ] Fixes: e49c7b2f6de7 ("afs: Build an abstraction around an "operation" concept") Reported-by: Abaci Robot Signed-off-by: Jiapeng Chong Signed-off-by: David Howells cc: linux-afs@lists.infradead.org Link: https://lore.kernel.org/r/1619691492-83866-1-git-send-email-jiapeng.chong@linux.alibaba.com Reviewed-by: Marc Dionne --- fs/afs/dir.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/afs/dir.c b/fs/afs/dir.c index 78719f2f567e..ac829e63c570 100644 --- a/fs/afs/dir.c +++ b/fs/afs/dir.c @@ -656,7 +656,6 @@ static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry, return ret; } - ret = -ENOENT; if (!cookie.found) { _leave(" = -ENOENT [not found]"); return -ENOENT; @@ -2020,17 +2019,20 @@ static int afs_rename(struct user_namespace *mnt_userns, struct inode *old_dir, if (d_count(new_dentry) > 2) { /* copy the target dentry's name */ - ret = -ENOMEM; op->rename.tmp = d_alloc(new_dentry->d_parent, &new_dentry->d_name); - if (!op->rename.tmp) + if (!op->rename.tmp) { + op->error = -ENOMEM; goto error; + } ret = afs_sillyrename(new_dvnode, AFS_FS_I(d_inode(new_dentry)), new_dentry, op->key); - if (ret) + if (ret) { + op->error = ret; goto error; + } op->dentry_2 = op->rename.tmp; op->rename.rehash = NULL;