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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A38AC433EF for ; Thu, 2 Dec 2021 00:21:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354253AbhLBAY2 (ORCPT ); Wed, 1 Dec 2021 19:24:28 -0500 Received: from sin.source.kernel.org ([145.40.73.55]:48364 "EHLO sin.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354205AbhLBAYV (ORCPT ); Wed, 1 Dec 2021 19:24:21 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id A6968CE212B; Thu, 2 Dec 2021 00:20:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C9019C53FCF; Thu, 2 Dec 2021 00:20:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1638404456; bh=QeXSCeOdNUAQWw42Nc34qkMPjGdidFzPUhtw438HvQc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PL517y4teSh4LYNHTykdZQGu52IoBbiJ5smuM7ZSJ1trQbS7WBGiTzgxhJ7m1I8/E GQFiLqS1FFMx39uB2D16szgHyGZVu2Mzlne5fyuZ6ZdG1G81rhG9tn6Joc15S6Y92O +IPjPecPmLc+3SYEZWUrpdyN/uAQELjxpLO/JDumHsX1/zXqiD1Qilouy0KPOjzKL1 KYwgl49P213HCwGxSyvdznhN+o5aC6NqnxJdPBCwFjV0OYkl1l5CA0EscFjFfaKy2C kImMpqDpXMRZBdNiLwdB7s2QQ1icaYXciNjeAxvaAJOL5fD8nWfx8f2dmWtooLiejE oFnC4ytmD58Uw== Received: by paulmck-ThinkPad-P17-Gen-1.home (Postfix, from userid 1000) id 88E025C1180; Wed, 1 Dec 2021 16:20:56 -0800 (PST) From: "Paul E. McKenney" To: rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, Jun Miao , Jianwei Hu , Uladzislau Rezki , Marco Elver , Juri Lelli , "Paul E . McKenney" Subject: [PATCH rcu 5/6] rcu: Avoid alloc_pages() when recording stack Date: Wed, 1 Dec 2021 16:20:54 -0800 Message-Id: <20211202002055.3127133-5-paulmck@kernel.org> X-Mailer: git-send-email 2.31.1.189.g2e36527f23 In-Reply-To: <20211202002031.GA3127068@paulmck-ThinkPad-P17-Gen-1> References: <20211202002031.GA3127068@paulmck-ThinkPad-P17-Gen-1> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jun Miao 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) Acked-by: Marco Elver Tested-by: Juri Lelli Signed-off-by: Jun Miao Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index f0f19dc7f19ec..c8beea8dd3a05 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2982,7 +2982,7 @@ __call_rcu(struct rcu_head *head, rcu_callback_t func) head->func = func; head->next = NULL; local_irq_save(flags); - kasan_record_aux_stack(head); + kasan_record_aux_stack_noalloc(head); rdp = this_cpu_ptr(&rcu_data); /* Add the callback to our list. */ @@ -3547,7 +3547,7 @@ void kvfree_call_rcu(struct rcu_head *head, rcu_callback_t func) return; } - kasan_record_aux_stack(ptr); + kasan_record_aux_stack_noalloc(ptr); success = add_ptr_to_bulk_krc_lock(&krcp, &flags, ptr, !head); if (!success) { run_page_cache_worker(krcp); -- 2.31.1.189.g2e36527f23