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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4DD0CC433EF for ; Tue, 16 Nov 2021 17:40:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 284F961BD4 for ; Tue, 16 Nov 2021 17:40:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238955AbhKPRnF (ORCPT ); Tue, 16 Nov 2021 12:43:05 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:46025 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238906AbhKPRnE (ORCPT ); Tue, 16 Nov 2021 12:43:04 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1637084407; 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: in-reply-to:in-reply-to:references:references; bh=Nr+r2xGROsXNBH9KeOUTHUo6tYTD1I9AjqYWE2OJRlU=; b=eqb4X7fV0LNXQT6/T2W3nkMKBMTh5F/+8QOXSSOc+4wCK1OgGsuan90v1tNXFjwwHh505o NiU6g9Io9XPeBbxAg5e474IsuPqYdFDZnkOxS7S+gmPTaLsqIYfb4Azx8Ct3RNxzjt9hCZ 4wm9HFDdf71hjUCMIZq693o/DPbuq8c= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-107-xul5daacNmObEPW47g2X5w-1; Tue, 16 Nov 2021 12:40:03 -0500 X-MC-Unique: xul5daacNmObEPW47g2X5w-1 Received: by mail-wr1-f71.google.com with SMTP id b1-20020a5d6341000000b001901ddd352eso3918562wrw.7 for ; Tue, 16 Nov 2021 09:40:02 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=Nr+r2xGROsXNBH9KeOUTHUo6tYTD1I9AjqYWE2OJRlU=; b=bVZeXF+loWLWXZVnm5hQtoOQnJYC7QCHcclg6lTxDK+q2JZ6kjapENxusNNVnLounY x7bmLIlj5cxNpFtOyih1r0y250iap8Dwbc6h+afYdnVh+mbCTIAKMQb6v4LIFinx9f9S DF7B7OqpSgnz8CAKohxuSFb06tBYoE4ZMmVZHNU7FCUueGMRET3uXJssxQEGlfoWrnuQ 089mD0VDqCJv1BquWdDsCyTac7knUL2ErJVTS6jwFoJWtL2Xf8DhrNiAq1BIjLKnwXYk 8tFUaiH99gd26bl5syfF88wp/xYm7P8yHV/3pxRSSjJ6aBXN3SDYDeSjRVFe2AEpdX6T 70YA== X-Gm-Message-State: AOAM5315WUowjhEhH5DRgM7aj87Ip9pPwmO8SzIQuIZ5dNmfD5xgWvN1 BGi6ut+NYaNsAaUX9ZtENLqwBtBqpVGQsc+vpy+XPiQ9BtiXUNzLPrjhjEg4FbTALwKSvlRO/kc F6tOwrs7sziYu75lYroCiOoR/ X-Received: by 2002:a05:600c:4f10:: with SMTP id l16mr9855682wmq.47.1637084401711; Tue, 16 Nov 2021 09:40:01 -0800 (PST) X-Google-Smtp-Source: ABdhPJxIaqukIZg2H4AH04sfIIA67Str6EuFC/VMDJ9CEaTdZiKqNmNI+IZ5i0hXoAFbt+HoaWJyvQ== X-Received: by 2002:a05:600c:4f10:: with SMTP id l16mr9855643wmq.47.1637084401466; Tue, 16 Nov 2021 09:40:01 -0800 (PST) Received: from localhost.localdomain ([2a00:23c6:4a17:4f01:3a16:ae0:112c:ba92]) by smtp.gmail.com with ESMTPSA id n1sm3718108wmq.6.2021.11.16.09.40.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Nov 2021 09:40:01 -0800 (PST) Date: Tue, 16 Nov 2021 17:39:59 +0000 From: Juri Lelli To: Jun Miao Cc: paulmck@kernel.org, urezki@gmail.com, elver@google.com, josh@joshtriplett.org, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, joel@joelfernandes.org, qiang.zhang1211@gmail.com, rcu@vger.kernel.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, jianwei.hu@windriver.com Subject: Re: [V2][PATCH] rcu: avoid alloc_pages() when recording stack Message-ID: <20211116173959.osdzlvv7niyxthd6@localhost.localdomain> References: <1637018582-10788-1-git-send-email-jun.miao@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1637018582-10788-1-git-send-email-jun.miao@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 16/11/21 07:23, Jun Miao wrote: > The default kasan_record_aux_stack() calls stack_depot_save() with GFP_NOWAIT, > which in turn can then call alloc_pages(GFP_NOWAIT, ...). In general, however, > it is not even possible to use either GFP_ATOMIC nor GFP_NOWAIT in certain > non-preemptive contexts/RT kernel including raw_spin_locks (see gfp.h and ab00db216c9c7). > Fix it by instructing stackdepot to not expand stack storage via alloc_pages() > in case it runs out by using kasan_record_aux_stack_noalloc(). > > Jianwei Hu reported: > BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:969 > in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 15319, name: python3 > INFO: lockdep is turned off. > irq event stamp: 0 > hardirqs last enabled at (0): [<0000000000000000>] 0x0 > hardirqs last disabled at (0): [] copy_process+0xaf3/0x2590 > softirqs last enabled at (0): [] copy_process+0xaf3/0x2590 > softirqs last disabled at (0): [<0000000000000000>] 0x0 > CPU: 6 PID: 15319 Comm: python3 Tainted: G W O 5.15-rc7-preempt-rt #1 > Hardware name: Supermicro SYS-E300-9A-8C/A2SDi-8C-HLN4F, BIOS 1.1b 12/17/2018 > Call Trace: > show_stack+0x52/0x58 > dump_stack+0xa1/0xd6 > ___might_sleep.cold+0x11c/0x12d > rt_spin_lock+0x3f/0xc0 > rmqueue+0x100/0x1460 > rmqueue+0x100/0x1460 > mark_usage+0x1a0/0x1a0 > ftrace_graph_ret_addr+0x2a/0xb0 > rmqueue_pcplist.constprop.0+0x6a0/0x6a0 > __kasan_check_read+0x11/0x20 > __zone_watermark_ok+0x114/0x270 > get_page_from_freelist+0x148/0x630 > is_module_text_address+0x32/0xa0 > __alloc_pages_nodemask+0x2f6/0x790 > __alloc_pages_slowpath.constprop.0+0x12d0/0x12d0 > create_prof_cpu_mask+0x30/0x30 > alloc_pages_current+0xb1/0x150 > stack_depot_save+0x39f/0x490 > kasan_save_stack+0x42/0x50 > kasan_save_stack+0x23/0x50 > kasan_record_aux_stack+0xa9/0xc0 > __call_rcu+0xff/0x9c0 > call_rcu+0xe/0x10 > put_object+0x53/0x70 > __delete_object+0x7b/0x90 > kmemleak_free+0x46/0x70 > slab_free_freelist_hook+0xb4/0x160 > kfree+0xe5/0x420 > kfree_const+0x17/0x30 > kobject_cleanup+0xaa/0x230 > kobject_put+0x76/0x90 > netdev_queue_update_kobjects+0x17d/0x1f0 > ... ... > ksys_write+0xd9/0x180 > __x64_sys_write+0x42/0x50 > do_syscall_64+0x38/0x50 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > Links: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/include/linux/kasan.h?id=7cb3007ce2da27ec02a1a3211941e7fe6875b642 > Fixes: 84109ab58590 ("rcu: Record kvfree_call_rcu() call stack for KASAN") > Fixes: 26e760c9a7c8 ("rcu: kasan: record and print call_rcu() call stack") > Reported-by: Jianwei Hu > Reviewed-by: Uladzislau Rezki (Sony) > Signed-off-by: Jun Miao > --- I gave this a quick try on RT. No splats. Nice! Tested-by: Juri Lelli Best, Juri