[{"id":1766828,"web_url":"http://patchwork.ozlabs.org/comment/1766828/","msgid":"<20170912094215.GB2036@nanopsycho>","list_archive_url":null,"date":"2017-09-12T09:42:15","subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","submitter":{"id":15321,"url":"http://patchwork.ozlabs.org/api/people/15321/","name":"Jiri Pirko","email":"jiri@resnulli.us"},"content":"Tue, Sep 12, 2017 at 01:33:30AM CEST, xiyou.wangcong@gmail.com wrote:\n>gen estimator has been rewritten in commit 1c0d32fde5bd\n>(\"net_sched: gen_estimator: complete rewrite of rate estimators\"),\n>the caller is no longer needed to wait for a grace period.\n>So this patch gets rid of it.\n>\n>This also completely closes a race condition between action free\n>path and filter chain add/remove path for the following patch.\n>Because otherwise the nested RCU callback can't be caught by\n>rcu_barrier().\n>\n>Please see also the comments in code.\n\nLooks like this is causing a null pointer dereference bug for me, 100%\nof the time. Just add and remove any rule with action and you get:\n\n\n[ 598.599825] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030\n[ 598.607782] IP: tcf_action_destroy+0xc0/0x140\n[ 598.612231] PGD 0 P4D 0 \n[ 598.614797] Oops: 0000 [#1] SMP KASAN\n[ 598.618525] Modules linked in: act_gact cls_flower sch_ingress rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache intel_rapl x86_pkg_temp_thermal coretemp mlxsw_spectrum kvm_intel mlxfw kvm parman bridge sunrpc irqbypass iTCO_wdt iTCO_vendor_support stp crct10dif_pclmul llc crc32_pclmul crc32c_intel mlxsw_pci ghash_clmulni_intel mlxsw_core i2c_i801 e1000e pcspkr ptp tpm_tis mei_me pps_core mei tpm_tis_core lpc_ich tpm shpchp video\n[ 598.659010] CPU: 1 PID: 758 Comm: bash Tainted: G B 4.13.0jiri+ #70\n[ 598.666509] Hardware name: Mellanox Technologies Ltd. Mellanox switch/Mellanox x86 mezzanine board, BIOS 4.6.5 08/02/2016\n[ 598.677630] task: ffff880371624bc0 task.stack: ffff880387808000\n[ 598.683648] RIP: 0010:tcf_action_destroy+0xc0/0x140\n[ 598.688617] RSP: 0018:ffff88038d107cb8 EFLAGS: 00010282\n[ 598.693922] RAX: 0000000000000000 RBX: ffff88038d107d28 RCX: ffffffff820b80e0\n[ 598.701184] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000030\n[ 598.708405] RBP: ffff88038d107ce8 R08: 0000000000000001 R09: 0000000000000001\n[ 598.715607] R10: ffff88038d107b27 R11: fffffbfff0bcf36c R12: 0000000000000000\n[ 598.722816] R13: ffff88038d107d38 R14: ffff88036bf75650 R15: 0000000000000001\n[ 598.730047] FS: 00007f398050b700(0000) GS:ffff88038d100000(0000) knlGS:0000000000000000\n[ 598.738253] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 598.744086] CR2: 0000000000000030 CR3: 0000000371ac4001 CR4: 00000000001606e0\n[ 598.751328] Call Trace:\n[ 598.753809] \n[ 598.755871] tcf_exts_destroy+0x17f/0x260\n[ 598.775969] fl_destroy_filter+0x1d/0x30 [cls_flower]\n[ 598.781069] rcu_process_callbacks+0x6b2/0xe00\n\n\nKasan says:\n\n[ 597.503005] BUG: KASAN: use-after-free in tcf_action_destroy+0xad/0x140\n[ 597.509751] Read of size 8 at addr ffff88036bf75640 by task bash/758\n[ 597.516222] \n[ 597.517761] CPU: 1 PID: 758 Comm: bash Not tainted 4.13.0jiri+ #70\n[ 597.524075] Hardware name: Mellanox Technologies Ltd. Mellanox switch/Mellanox x86 mezzanine board, BIOS 4.6.5 08/02/2016\n[ 597.535132] Call Trace:\n[ 597.537630] \n[ 597.539718] dump_stack+0xd5/0x150\n[ 597.554853] print_address_description+0x86/0x410\n[ 597.559667] kasan_report+0x181/0x4c0\n[ 597.583360] tcf_action_destroy+0xad/0x140\n[ 597.587551] tcf_exts_destroy+0x17f/0x260\n\n\nUbsan says:\n\n[ 598.184033] UBSAN: Undefined behaviour in net/sched/act_api.c:523:4\n[ 598.190409] member access within null pointer of type 'const struct tc_action_ops'\n[ 598.198076] CPU: 1 PID: 758 Comm: bash Tainted: G B 4.13.0jiri+ #70\n[ 598.205570] Hardware name: Mellanox Technologies Ltd. Mellanox switch/Mellanox x86 mezzanine board, BIOS 4.6.5 08/02/2016\n[ 598.216669] Call Trace:\n[ 598.219157] \n[ 598.221245] dump_stack+0xd5/0x150\n[ 598.228703] ubsan_epilogue+0xd/0x4e\n[ 598.232333] __ubsan_handle_type_mismatch+0xf2/0x293\n[ 598.252880] tcf_action_destroy+0x115/0x140\n[ 598.257151] tcf_exts_destroy+0x17f/0x260\n[ 598.277336] fl_destroy_filter+0x1d/0x30 [cls_flower]\n[ 598.282472] rcu_process_callbacks+0x6b2/0xe00\n\nLooks like you need to save owner of the module before you call\n__tcf_idr_release so you can later on use it for module_put","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=resnulli-us.20150623.gappssmtp.com\n\theader.i=@resnulli-us.20150623.gappssmtp.com\n\theader.b=\"o8lL+AIF\"; 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charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"<20170911233332.7594-2-xiyou.wangcong@gmail.com>","User-Agent":"Mutt/1.8.3 (2017-05-23)","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}},{"id":1766861,"web_url":"http://patchwork.ozlabs.org/comment/1766861/","msgid":"<20170912104004.GE2036@nanopsycho>","list_archive_url":null,"date":"2017-09-12T10:40:04","subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","submitter":{"id":15321,"url":"http://patchwork.ozlabs.org/api/people/15321/","name":"Jiri Pirko","email":"jiri@resnulli.us"},"content":"Tue, Sep 12, 2017 at 11:42:15AM CEST, jiri@resnulli.us wrote:\n>Tue, Sep 12, 2017 at 01:33:30AM CEST, xiyou.wangcong@gmail.com wrote:\n>>gen estimator has been rewritten in commit 1c0d32fde5bd\n>>(\"net_sched: gen_estimator: complete rewrite of rate estimators\"),\n>>the caller is no longer needed to wait for a grace period.\n>>So this patch gets rid of it.\n>>\n>>This also completely closes a race condition between action free\n>>path and filter chain add/remove path for the following patch.\n>>Because otherwise the nested RCU callback can't be caught by\n>>rcu_barrier().\n>>\n>>Please see also the comments in code.\n>\n>Looks like this is causing a null pointer dereference bug for me, 100%\n>of the time. Just add and remove any rule with action and you get:\n>\n\n[...]\n\n>\n>Looks like you need to save owner of the module before you call\n>__tcf_idr_release so you can later on use it for module_put\n\nThis patch helps:\n\ndiff --git a/net/sched/act_api.c b/net/sched/act_api.c\nindex fcd7dc7..de73e71 100644\n--- a/net/sched/act_api.c\n+++ b/net/sched/act_api.c\n@@ -514,13 +514,15 @@ EXPORT_SYMBOL(tcf_action_exec);\n \n int tcf_action_destroy(struct list_head *actions, int bind)\n {\n+\tconst struct tc_action_ops *ops;\n \tstruct tc_action *a, *tmp;\n \tint ret = 0;\n \n \tlist_for_each_entry_safe(a, tmp, actions, list) {\n+\t\tops = a->ops;\n \t\tret = __tcf_idr_release(a, bind, true);\n \t\tif (ret == ACT_P_DELETED)\n-\t\t\tmodule_put(a->ops->owner);\n+\t\t\tmodule_put(ops->owner);\n \t\telse if (ret < 0)\n \t\t\treturn ret;\n \t}","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; 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charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"<20170912094215.GB2036@nanopsycho>","User-Agent":"Mutt/1.8.3 (2017-05-23)","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}},{"id":1767337,"web_url":"http://patchwork.ozlabs.org/comment/1767337/","msgid":"","list_archive_url":null,"date":"2017-09-12T21:10:22","subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","submitter":{"id":211,"url":"http://patchwork.ozlabs.org/api/people/211/","name":"Cong Wang","email":"xiyou.wangcong@gmail.com"},"content":"On Tue, Sep 12, 2017 at 3:40 AM, Jiri Pirko wrote:\n> Tue, Sep 12, 2017 at 11:42:15AM CEST, jiri@resnulli.us wrote:\n>>Tue, Sep 12, 2017 at 01:33:30AM CEST, xiyou.wangcong@gmail.com wrote:\n>>>gen estimator has been rewritten in commit 1c0d32fde5bd\n>>>(\"net_sched: gen_estimator: complete rewrite of rate estimators\"),\n>>>the caller is no longer needed to wait for a grace period.\n>>>So this patch gets rid of it.\n>>>\n>>>This also completely closes a race condition between action free\n>>>path and filter chain add/remove path for the following patch.\n>>>Because otherwise the nested RCU callback can't be caught by\n>>>rcu_barrier().\n>>>\n>>>Please see also the comments in code.\n>>\n>>Looks like this is causing a null pointer dereference bug for me, 100%\n>>of the time. Just add and remove any rule with action and you get:\n>>\n>\n> [...]\n>\n>>\n>>Looks like you need to save owner of the module before you call\n>>__tcf_idr_release so you can later on use it for module_put\n\nWhy do you believe it is this patch introduces the bug?\n\nThat code has been there since the beginning of git history:\n\n+ for (a = act; a; a = act) {\n+ if (a->ops && a->ops->cleanup) {\n+ DPRINTK(\"tcf_action_destroy destroying %p next %p\\n\",\n+ a, a->next);\n+ if (a->ops->cleanup(a, bind) == ACT_P_DELETED)\n+ module_put(a->ops->owner);\n+ act = act->next;\n\nSeems to be a very old one. The reason why it exposes, I guess,\nis call_rcu() somehow delays the free after module_put().\n\n\n>\n> This patch helps:\n\nLooks good to me. Please feel free to submit a formal patch.","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"nCPnKr1Z\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xsHWs1FfVz9t2Z\n\tfor ;\n\tWed, 13 Sep 2017 07:10:49 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751003AbdILVKq (ORCPT );\n\tTue, 12 Sep 2017 17:10:46 -0400","from mail-pf0-f193.google.com ([209.85.192.193]:36384 \"EHLO\n\tmail-pf0-f193.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1750949AbdILVKn (ORCPT\n\t); Tue, 12 Sep 2017 17:10:43 -0400","by mail-pf0-f193.google.com with SMTP id f84so6680097pfj.3\n\tfor ; Tue, 12 Sep 2017 14:10:43 -0700 (PDT)","by 10.100.160.131 with HTTP; Tue, 12 Sep 2017 14:10:22 -0700 (PDT)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=gmail.com; s=20161025;\n\th=mime-version:in-reply-to:references:from:date:message-id:subject:to\n\t:cc; bh=df2TWugObs6DV/WQYikn5DaK9p5ij4suqlJoRKMnm64=;\n\tb=nCPnKr1ZWkC+asY5gCp05d4xHlMOMCb3yNd9hUCo2cac2QfZwm9gbOV2Xz4CZ2pb1F\n\tbmEMbH8Y8YDjKZ49Jr2Wfb7eWA8zJi35jUkFZM3W+LEg5iuz4gFZFiHIM92yyQXsYvqU\n\tCnGuM2/QSDRP5Fg5BK087mMWSOXHn34vDemdnUqN5dCYXNjIvhaAKftbqlHmkiKSmnal\n\tFNPCPdzrjnv2xFngVENAQlBorUNRshRV29k3zGx8NRsKC0MY687q6jFixJhuZkdXp+SD\n\tTK3B5zj0mXNdnwDepsPPjZ65NykCUrve1lTlTKnjbzhJPVB1UKeGvqo/xrkShQttpotP\n\t8DMQ==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:mime-version:in-reply-to:references:from:date\n\t:message-id:subject:to:cc;\n\tbh=df2TWugObs6DV/WQYikn5DaK9p5ij4suqlJoRKMnm64=;\n\tb=Suoj6T/WJkSVIFjLYfBPhxAa2T5gNRxH6CAmxp27uSG4T1fkGUknkoybw/MPXYUI1q\n\txmJZQf1/jGknCVyGx7/lcTa/O73fEkyIYe2A8FMVJ0DVuU7VHOr0txNfb4GR4Zane1jb\n\t70Oe9Xs60HJEQYl27F3+b45spT3fyJDzaAXnw4Cxxo+2QBTSi0qXbwoUacI/yKSFNoJh\n\tFRYKXr9LDhbDY7I5Ct6jGEJpFa+hW+Qyi2BAnSwBRQLlZNO9pB+jI5VqaUMMTwobyAMo\n\tkJXvH+MuBoLlRjfSA5tWMQYq5AMiWQUI/oDARsx6oYK+b/T9UUfI/LoysRX+VEnkA1ab\n\tuJXQ==","X-Gm-Message-State":"AHPjjUhMVj53yEb6eFCZ8lvPzKAXV1Hj2TIbdGxS0GDFHPYTm1NgfCCi\n\t5WL5qKgLendwqezmte4XupILYpqnr6G5HAb3pc/n5dqy","X-Google-Smtp-Source":"ADKCNb4+8fa5zFzEfRighv0KMhV7homxBOaTHv1T3EHRmoijmO4N/51oRdHM95hvvwwU5PeEQ7BIYMF6BLSOuZRrd14=","X-Received":"by 10.98.26.74 with SMTP id a71mr16159271pfa.286.1505250643245; \n\tTue, 12 Sep 2017 14:10:43 -0700 (PDT)","MIME-Version":"1.0","In-Reply-To":"<20170912104004.GE2036@nanopsycho>","References":"<20170911233332.7594-1-xiyou.wangcong@gmail.com>\n\t<20170911233332.7594-2-xiyou.wangcong@gmail.com>\n\t<20170912094215.GB2036@nanopsycho>\n\t<20170912104004.GE2036@nanopsycho>","From":"Cong Wang ","Date":"Tue, 12 Sep 2017 14:10:22 -0700","Message-ID":"","Subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","To":"Jiri Pirko ","Cc":"Linux Kernel Network Developers ,\n\tJiri Pirko ,\n\tJakub Kicinski ,\n\tJamal Hadi Salim , Eric Dumazet ","Content-Type":"text/plain; charset=\"UTF-8\"","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}},{"id":1767373,"web_url":"http://patchwork.ozlabs.org/comment/1767373/","msgid":"<20170912213634.GS2036@nanopsycho>","list_archive_url":null,"date":"2017-09-12T21:36:34","subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","submitter":{"id":15321,"url":"http://patchwork.ozlabs.org/api/people/15321/","name":"Jiri Pirko","email":"jiri@resnulli.us"},"content":"Tue, Sep 12, 2017 at 11:10:22PM CEST, xiyou.wangcong@gmail.com wrote:\n>On Tue, Sep 12, 2017 at 3:40 AM, Jiri Pirko wrote:\n>> Tue, Sep 12, 2017 at 11:42:15AM CEST, jiri@resnulli.us wrote:\n>>>Tue, Sep 12, 2017 at 01:33:30AM CEST, xiyou.wangcong@gmail.com wrote:\n>>>>gen estimator has been rewritten in commit 1c0d32fde5bd\n>>>>(\"net_sched: gen_estimator: complete rewrite of rate estimators\"),\n>>>>the caller is no longer needed to wait for a grace period.\n>>>>So this patch gets rid of it.\n>>>>\n>>>>This also completely closes a race condition between action free\n>>>>path and filter chain add/remove path for the following patch.\n>>>>Because otherwise the nested RCU callback can't be caught by\n>>>>rcu_barrier().\n>>>>\n>>>>Please see also the comments in code.\n>>>\n>>>Looks like this is causing a null pointer dereference bug for me, 100%\n>>>of the time. Just add and remove any rule with action and you get:\n>>>\n>>\n>> [...]\n>>\n>>>\n>>>Looks like you need to save owner of the module before you call\n>>>__tcf_idr_release so you can later on use it for module_put\n>\n>Why do you believe it is this patch introduces the bug?\n>\n>That code has been there since the beginning of git history:\n>\n>+ for (a = act; a; a = act) {\n>+ if (a->ops && a->ops->cleanup) {\n>+ DPRINTK(\"tcf_action_destroy destroying %p next %p\\n\",\n>+ a, a->next);\n>+ if (a->ops->cleanup(a, bind) == ACT_P_DELETED)\n>+ module_put(a->ops->owner);\n>+ act = act->next;\n>\n>Seems to be a very old one. The reason why it exposes, I guess,\n>is call_rcu() somehow delays the free after module_put().\n\nYeah, looks like the race was just hard to hit. However with your patch,\nit is very easy to hit.\n\n\n>\n>\n>>\n>> This patch helps:\n>\n>Looks good to me. Please feel free to submit a formal patch.\n\nOkay, I will send the patch to you formally so you can add it as a first\npatch of your patchset.","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=resnulli-us.20150623.gappssmtp.com\n\theader.i=@resnulli-us.20150623.gappssmtp.com\n\theader.b=\"jXEWLz4g\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xsJ652htYz9t3J\n\tfor ;\n\tWed, 13 Sep 2017 07:37:01 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751105AbdILVgh (ORCPT );\n\tTue, 12 Sep 2017 17:36:37 -0400","from mail-wr0-f193.google.com ([209.85.128.193]:34933 \"EHLO\n\tmail-wr0-f193.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1750962AbdILVgg (ORCPT\n\t); Tue, 12 Sep 2017 17:36:36 -0400","by mail-wr0-f193.google.com with SMTP id n64so6839076wrb.2\n\tfor ; Tue, 12 Sep 2017 14:36:36 -0700 (PDT)","from localhost (ip-89-177-125-82.net.upcbroadband.cz.\n\t[89.177.125.82]) by smtp.gmail.com with ESMTPSA id\n\tb184sm7405580wmf.13.2017.09.12.14.36.34\n\t(version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256);\n\tTue, 12 Sep 2017 14:36:34 -0700 (PDT)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=resnulli-us.20150623.gappssmtp.com; s=20150623;\n\th=date:from:to:cc:subject:message-id:references:mime-version\n\t:content-disposition:in-reply-to:user-agent;\n\tbh=68zksri37ao424JqETsriuamZu/T/BYc4L8wnyYVEY8=;\n\tb=jXEWLz4gnOhtPMtvyI8tea4M/+MsjzW/Fz2JoXoE1JN19OJdK/4d4lGtRBodgcsHo+\n\tTtr2xKazLYf4iyR9wRd8zQs/3OjpBzzEtrBo01DKOt2UGA+D2oWqcWtWhxloQYALQE6x\n\t5ssqH7JWNy9YflXdY+fRZ+dQPeu2LXDlBUSD8r3Y1j6tKJU+RIReZlbLxNol+cMEATQP\n\t0oyqAywXaj80t4q2DySR8iiQSJ2boxGHTyTMS9ljM3LazGbpGU34RcEECcE0XqbtPhVU\n\tR7OTIAejWQXJ7fGyrN0EFWA9Vc4bnv2NmSwv+uD7Z0XcidjdO2F4pgrr+qIfhTWckF8v\n\t4WQw==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:date:from:to:cc:subject:message-id:references\n\t:mime-version:content-disposition:in-reply-to:user-agent;\n\tbh=68zksri37ao424JqETsriuamZu/T/BYc4L8wnyYVEY8=;\n\tb=q73ZeNxH9Cjn2q94YqaWZMkCCy2n96bewq9ykBHLdb1LxYpx39FoHHDa2vREDVanW/\n\tAkQQRhB8V2xNG0jqwB34hb/coT0D73f3MfJA2LP09YftaNFRVyX9tZpO0Pa6FIzIW3sU\n\t9wTJZvEtpovaRCMNRDPvtVv9qM734JosWBLCiOpz13slt0GlLT/+aeQwe0WJsfYaKZu4\n\tSYjuAsf/HUyPUKGB1QvRCbSkcv51AIkzJzWhi+2+JeMjb+YBuFxUXtcd8MCnhCHvO+bv\n\txAgw6O7eUgCt2+Cr08n1QCKDMxXQ/ashSAfw7sChb5CEEJEoF6KPJfdaJGcHWFcLjVIc\n\tkyFg==","X-Gm-Message-State":"AHPjjUjFqkhUPLXhqPzNnhCi0j5blhg0O/r1ZV88fZXkmd0H8gwNl1xX\n\tvtmCpLusDAIolmiE","X-Google-Smtp-Source":"ADKCNb7NzUHl7Ffirc5NW9+YTrZJ86vLr7kKI/0z1HYrZZhtNbYwTBPU2MGcYOenxFgw6MHfXH802Q==","X-Received":"by 10.223.142.73 with SMTP id n67mr12787120wrb.278.1505252195484;\n\tTue, 12 Sep 2017 14:36:35 -0700 (PDT)","Date":"Tue, 12 Sep 2017 23:36:34 +0200","From":"Jiri Pirko ","To":"Cong Wang ","Cc":"Linux Kernel Network Developers ,\n\tJiri Pirko ,\n\tJakub Kicinski ,\n\tJamal Hadi Salim , Eric Dumazet ","Subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","Message-ID":"<20170912213634.GS2036@nanopsycho>","References":"<20170911233332.7594-1-xiyou.wangcong@gmail.com>\n\t<20170911233332.7594-2-xiyou.wangcong@gmail.com>\n\t<20170912094215.GB2036@nanopsycho>\n\t<20170912104004.GE2036@nanopsycho>\n\t","MIME-Version":"1.0","Content-Type":"text/plain; charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"","User-Agent":"Mutt/1.8.3 (2017-05-23)","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}},{"id":1767398,"web_url":"http://patchwork.ozlabs.org/comment/1767398/","msgid":"","list_archive_url":null,"date":"2017-09-12T21:53:09","subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","submitter":{"id":211,"url":"http://patchwork.ozlabs.org/api/people/211/","name":"Cong Wang","email":"xiyou.wangcong@gmail.com"},"content":"On Tue, Sep 12, 2017 at 2:36 PM, Jiri Pirko wrote:\n> Tue, Sep 12, 2017 at 11:10:22PM CEST, xiyou.wangcong@gmail.com wrote:\n>>On Tue, Sep 12, 2017 at 3:40 AM, Jiri Pirko wrote:\n>>> This patch helps:\n>>\n>>Looks good to me. Please feel free to submit a formal patch.\n>\n> Okay, I will send the patch to you formally so you can add it as a first\n> patch of your patchset.\n\nI can carry it by myself if it fits to this patchset. However, I believe it\nshould be independent since it has to be backported much further\nthan this patchset. I don't know why no one triggered the crash\nbefore call_rcu() was introduced there.\n\nAnyway, I believe you should submit your patch alone, either before\nor after this patchset, there should be no conflict.","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=gmail.com header.i=@gmail.com\n\theader.b=\"mQAwK5A7\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xsJTC3RmWz9t33\n\tfor ;\n\tWed, 13 Sep 2017 07:53:35 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751193AbdILVxd (ORCPT );\n\tTue, 12 Sep 2017 17:53:33 -0400","from mail-pf0-f175.google.com ([209.85.192.175]:35490 \"EHLO\n\tmail-pf0-f175.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1750988AbdILVxa (ORCPT\n\t); Tue, 12 Sep 2017 17:53:30 -0400","by mail-pf0-f175.google.com with SMTP id q76so7021257pfq.2\n\tfor ; Tue, 12 Sep 2017 14:53:30 -0700 (PDT)","by 10.100.160.131 with HTTP; Tue, 12 Sep 2017 14:53:09 -0700 (PDT)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=gmail.com; s=20161025;\n\th=mime-version:in-reply-to:references:from:date:message-id:subject:to\n\t:cc; bh=pwa/td5ElFN95rE/umQ4b9FV+M3a0ZqSUG0MHi7RtpI=;\n\tb=mQAwK5A70yODCgSBz1Ib8wQx+FL0kOk1QhbsTrirCdaDBggT+0j2yqZ2e+LwNorHjK\n\tlNiynLOgtCiKo7ctEil7fVnFOS2DgVkeKekF87I6GcNqmoqYXzqxDFqTj2li9tyuAoev\n\tRvWFqhExFKzDHytUvX/m/MZga/z5V1nZ41b7uDtgYuSpF8gUlPrIfJf3a+IeDdjXD3PG\n\tKmgTik4lWl1B7z9OI+2DXGd1Xs/o5/QBw0LbZ6cJK5MQiUT1VSinM7gX1d3B0DvFJQ0l\n\tEXk83gQAdgVmHbqWRADaG+LYjQtf9HUBidIIzXcYe2IUoUHpPbUZwSpuO5CX/HZPSjMh\n\tzD/Q==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:mime-version:in-reply-to:references:from:date\n\t:message-id:subject:to:cc;\n\tbh=pwa/td5ElFN95rE/umQ4b9FV+M3a0ZqSUG0MHi7RtpI=;\n\tb=bfNpXqhgLjcfhQAvpmNb6deIRoKYdk5gplOgm08iCgFAFro8Zs7g3wM/VhcG4CzEkR\n\t4HbXk8GpeQGhJy/+aNtlcer2LjhGIgUB8etPAi11fEq00cm0Ex9L4D0FkMHLc4Si9tO5\n\thf5NbDdwDRDhn3gbrAaCE54PYsCPlwAGKHMoQvst7/v45U6b3XNJhHiY8OvRsrxFO4eD\n\tk+Dj0TkhmB+bK3VYtmhMY7t0K3jFXxPLzoRC2BwlpGhKbvSN0UaymCXtdQzYpswe0XVj\n\t0GjoZIKil0xLzkPa+Y6qcWvFNEgsyfxY+mgPqexPPwxKcGNGgK3nhRg4dR0NutSqdkbz\n\t5dlQ==","X-Gm-Message-State":"AHPjjUjxHzLDaqvaeMeWs+kFJpGZ+ZcJr1l7AWtg+NtBPYXHc0mlSq0s\n\tFHio4tdpJ5JIis408KRXYsa5dgdjsPwan7Ij7E9dgQ==","X-Google-Smtp-Source":"ADKCNb6RxwgepO/jD4tcdeDRvL0XjFvWA4bRKieed9htXPpqRAr2sZkPa7LkBR64/B3oL/yDt0A1TXATCMA7ZM0VNbs=","X-Received":"by 10.101.92.204 with SMTP id b12mr15718197pgt.54.1505253210313; \n\tTue, 12 Sep 2017 14:53:30 -0700 (PDT)","MIME-Version":"1.0","In-Reply-To":"<20170912213634.GS2036@nanopsycho>","References":"<20170911233332.7594-1-xiyou.wangcong@gmail.com>\n\t<20170911233332.7594-2-xiyou.wangcong@gmail.com>\n\t<20170912094215.GB2036@nanopsycho>\n\t<20170912104004.GE2036@nanopsycho>\n\t\n\t<20170912213634.GS2036@nanopsycho>","From":"Cong Wang ","Date":"Tue, 12 Sep 2017 14:53:09 -0700","Message-ID":"","Subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","To":"Jiri Pirko ","Cc":"Linux Kernel Network Developers ,\n\tJiri Pirko ,\n\tJakub Kicinski ,\n\tJamal Hadi Salim , Eric Dumazet ","Content-Type":"text/plain; charset=\"UTF-8\"","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}},{"id":1767590,"web_url":"http://patchwork.ozlabs.org/comment/1767590/","msgid":"<20170913061310.GA1922@nanopsycho>","list_archive_url":null,"date":"2017-09-13T06:13:10","subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","submitter":{"id":15321,"url":"http://patchwork.ozlabs.org/api/people/15321/","name":"Jiri Pirko","email":"jiri@resnulli.us"},"content":"Tue, Sep 12, 2017 at 11:53:09PM CEST, xiyou.wangcong@gmail.com wrote:\n>On Tue, Sep 12, 2017 at 2:36 PM, Jiri Pirko wrote:\n>> Tue, Sep 12, 2017 at 11:10:22PM CEST, xiyou.wangcong@gmail.com wrote:\n>>>On Tue, Sep 12, 2017 at 3:40 AM, Jiri Pirko wrote:\n>>>> This patch helps:\n>>>\n>>>Looks good to me. Please feel free to submit a formal patch.\n>>\n>> Okay, I will send the patch to you formally so you can add it as a first\n>> patch of your patchset.\n>\n>I can carry it by myself if it fits to this patchset. However, I believe it\n>should be independent since it has to be backported much further\n>than this patchset. I don't know why no one triggered the crash\n>before call_rcu() was introduced there.\n>\n>Anyway, I believe you should submit your patch alone, either before\n>or after this patchset, there should be no conflict.\n\nOkay. Will to it before the patchset. Thanks!","headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ozlabs.org; dkim=pass (2048-bit key;\n\tunprotected) header.d=resnulli-us.20150623.gappssmtp.com\n\theader.i=@resnulli-us.20150623.gappssmtp.com\n\theader.b=\"0gC3iEDj\"; dkim-atps=neutral"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xsWYq0zmYz9sRV\n\tfor ;\n\tWed, 13 Sep 2017 16:13:19 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1751117AbdIMGNP (ORCPT );\n\tWed, 13 Sep 2017 02:13:15 -0400","from mail-wr0-f177.google.com ([209.85.128.177]:37064 \"EHLO\n\tmail-wr0-f177.google.com\" rhost-flags-OK-OK-OK-OK) by vger.kernel.org\n\twith ESMTP id S1750869AbdIMGNO (ORCPT\n\t); Wed, 13 Sep 2017 02:13:14 -0400","by mail-wr0-f177.google.com with SMTP id k20so26438450wre.4\n\tfor ; Tue, 12 Sep 2017 23:13:13 -0700 (PDT)","from localhost (ip-89-177-125-82.net.upcbroadband.cz.\n\t[89.177.125.82])\n\tby smtp.gmail.com with ESMTPSA id v5sm856299wmb.0.2017.09.12.23.13.10\n\t(version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256);\n\tTue, 12 Sep 2017 23:13:11 -0700 (PDT)"],"DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=resnulli-us.20150623.gappssmtp.com; s=20150623;\n\th=date:from:to:cc:subject:message-id:references:mime-version\n\t:content-disposition:in-reply-to:user-agent;\n\tbh=DeICzXAiOczPqkGXvoC4YcjnS5wR6Q7QX1G+wCtYveQ=;\n\tb=0gC3iEDjLmfi3aeia1wTNL4SKOhwD3cO+TRcCcarM1wiqjfCNqvLm06iwWjNnTQ0EA\n\tviLV2c2QZRlCDTlD+ruOGiFJZ4PxfyTr2DqJnBQ88VwLVwhrcYqeV6OwdVih68GKQzr6\n\txewx0IeDicDMTLg2j2vH07ofoJmWFnnqFrvStnFoQ4QwBYNSEGcoEhYtcsaGvY+YHLHE\n\tEiM8FLG6PJ8v3v3V63bsO5XFBlhFo+93Y4ZQEHfpi+k965pyJKxQX2ir6oNFcWz71jn6\n\tf2rNqkiWxLUO7R+9ImYoafbICUCAan2G5HHWMCvNqNbJgYk1oJD5FzqyQM6E8U7c0bJt\n\t8SuQ==","X-Google-DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:date:from:to:cc:subject:message-id:references\n\t:mime-version:content-disposition:in-reply-to:user-agent;\n\tbh=DeICzXAiOczPqkGXvoC4YcjnS5wR6Q7QX1G+wCtYveQ=;\n\tb=iUI4yyHp5/9wAMV5FKC0cwP6KTY4hQtXlUtACkvpvqtOgMdplF42jMfZwfisQpIWwv\n\t4+bw2QQDl+it5CsVdSWflMV8Scf1/RnCtsInY8dTbwEqQgcao4a/PO3wHrlq5YVXZ18i\n\tWAIRtQXQb1bxjn63V2B1RlhjxJOi/KRjiGao4goa4nBzwFyOG3TGVLFBWdy6K7nsTKIF\n\tJQ9gMOAgXyHyrNl8RR8q7U0Raw7MglDpRB2fN11t+quejFyabOcX1qx1W2LaWBN76hTG\n\tFYGlkKskJGh5VvQenOLRJQRF/Wjr/GrnOzTLPxuVsbNEzgQJEOT1lRuM3ziNZCRtFxd9\n\tfy1g==","X-Gm-Message-State":"AHPjjUiwPn0sN1yurvgaSKCjL+2I7wzmDhVVAxQiXM0QBJOjspJ0wsaP\n\th3dfVmpS05+U0tdP","X-Google-Smtp-Source":"ADKCNb7e7ZfCWR4ojRW1vA3hPLGftsvl42nhHVlM3LiHoGqdzAnfQ32VzN9D+9y3Pj2mJHPwVrMK8g==","X-Received":"by 10.223.147.166 with SMTP id 35mr16435209wrp.90.1505283192709; \n\tTue, 12 Sep 2017 23:13:12 -0700 (PDT)","Date":"Wed, 13 Sep 2017 08:13:10 +0200","From":"Jiri Pirko ","To":"Cong Wang ","Cc":"Linux Kernel Network Developers ,\n\tJiri Pirko ,\n\tJakub Kicinski ,\n\tJamal Hadi Salim , Eric Dumazet ","Subject":"Re: [Patch net v3 1/3] net_sched: get rid of tcfa_rcu","Message-ID":"<20170913061310.GA1922@nanopsycho>","References":"<20170911233332.7594-1-xiyou.wangcong@gmail.com>\n\t<20170911233332.7594-2-xiyou.wangcong@gmail.com>\n\t<20170912094215.GB2036@nanopsycho>\n\t<20170912104004.GE2036@nanopsycho>\n\t\n\t<20170912213634.GS2036@nanopsycho>\n\t","MIME-Version":"1.0","Content-Type":"text/plain; charset=us-ascii","Content-Disposition":"inline","In-Reply-To":"","User-Agent":"Mutt/1.8.3 (2017-05-23)","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"}}]