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 2EC71C433F5 for ; Thu, 10 Mar 2022 09:36:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234920AbiCJJhB (ORCPT ); Thu, 10 Mar 2022 04:37:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50478 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230107AbiCJJhB (ORCPT ); Thu, 10 Mar 2022 04:37:01 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80D1813A1ED; Thu, 10 Mar 2022 01:36:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=irYEUP1LT5nKyhqvu9/7+diZD18yg6h9RclMUqCTiQc=; b=N0t7WEhdE6u1lZitiQcVOtvC6R L38cospM2R9+1sl5T4IcUHRAckeRgvvSsw6rKbwkO31ku+d9bN+F2sGfE7LqJ5awdeq77cGgZ7o94 T5/F1X7nn77kYNEuIlmo+bKxLhO+totKRMvaQDOrzDUqX5v0aOsiwSpZ2dfIJ4YA9sujVUa3CKMcL rO2+Y9lVnP+4iqNEyNMqVI5BC5P2DUYnrU8nYpoTnIbtezeFfb63GFPlcVq9arMHV3N+G7qJgXyPO HHPTUy+jCjd60hWnbcBCqw7Ukcb4nmeLFWeLw1J5LnRRuMDLD9Wyp8IVhwpLAglzqTQ8v5+a3hqLY xP2KazhQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nSFCo-000ODF-8c; Thu, 10 Mar 2022 09:35:34 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id A26ED300268; Thu, 10 Mar 2022 10:35:32 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 5F120264E62B7; Thu, 10 Mar 2022 10:35:32 +0100 (CET) Date: Thu, 10 Mar 2022 10:35:32 +0100 From: Peter Zijlstra To: Alexei Starovoitov Cc: x86@kernel.org, joao@overdrivepizza.com, hjl.tools@gmail.com, jpoimboe@redhat.com, andrew.cooper3@citrix.com, linux-kernel@vger.kernel.org, ndesaulniers@google.com, keescook@chromium.org, samitolvanen@google.com, mark.rutland@arm.com, alyssa.milburn@intel.com, mbenes@suse.cz, rostedt@goodmis.org, mhiramat@kernel.org, daniel@iogearbox.net, andrii@kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH v4 00/45] x86: Kernel IBT Message-ID: References: <20220308153011.021123062@infradead.org> <20220308200052.rpr4vkxppnxguirg@ast-mbp.dhcp.thefacebook.com> <20220309190917.w3tq72alughslanq@ast-mbp.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220309190917.w3tq72alughslanq@ast-mbp.dhcp.thefacebook.com> Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Wed, Mar 09, 2022 at 11:09:17AM -0800, Alexei Starovoitov wrote: > Pulled above and it got even worse. > With kasan and lockdep during qemu boot I see: > [ 1.147498] rcu_scheduler_active = 1, debug_locks = 1 > [ 1.147498] 2 locks held by kthreadd/2: > [ 1.147498] #0: ffff888100362b80 (&p->pi_lock){....}-{2:2}, at: task_rq_lock+0x71/0x380 > [ 1.147498] #1: ffff8881f6a3a218 (&rq->__lock){-...}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x40 > [ 1.147498] > [ 1.147498] stack backtrace: > [ 1.147498] CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.17.0-rc7-02289-gc958c6aae879 #1 > [ 1.147498] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 > [ 1.147498] Call Trace: > [ 1.147498] > [ 1.147498] dump_stack_lvl+0x48/0x5b > [ 1.147498] cpuacct_charge+0x2b3/0x390 > [ 1.147498] update_curr+0x33e/0x7d0 > [ 1.147498] dequeue_entity+0x28/0xdf0 > [ 1.147498] ? rcu_read_lock_bh_held+0xa0/0xa0 > [ 1.147498] dequeue_task_fair+0x1fa/0xd60 > [ 1.147498] __do_set_cpus_allowed+0x253/0x620 > [ 1.147498] __set_cpus_allowed_ptr_locked+0x25f/0x450 > [ 1.147498] __set_cpus_allowed_ptr+0x7c/0xa0 > [ 1.147498] ? __set_cpus_allowed_ptr_locked+0x450/0x450 > [ 1.147498] ? _raw_spin_unlock_irqrestore+0x34/0x60 > [ 1.147498] ? lockdep_hardirqs_on+0x7d/0x100 > [ 1.147498] kthreadd+0x48/0x610 > [ 1.147498] ? _raw_spin_unlock_irq+0x28/0x50 > [ 1.147498] ? kthread_is_per_cpu+0xc0/0xc0 > [ 1.147498] ret_from_fork+0x1f/0x30 Yeah, sorry about that, currently arguing with Paul about that one. Should go away if you disable the RCU lockdep thing. The warning itself is a false positive and more harmful than anything else due to it generating a possible printk deadlock. > Most of the time it hangs during the boot. > I'm using gcc 8.5 and qemu -smp 8 > With qemu -smp 1 it luckly boots. > Then I run test_progs and see: > Summary: 215/1115 PASSED, 4 SKIPPED, 18 FAILED > All trampoline tests fail. > Here is one: > $ test_progs -t fentry > test_fentry_fexit:PASS:fentry_skel_load 0 nsec > test_fentry_fexit:PASS:fexit_skel_load 0 nsec > test_fentry_fexit:PASS:fentry_attach 0 nsec > test_fentry_fexit:FAIL:fexit_attach unexpected error: -1 (errno 19) > #54 fentry_fexit:FAIL > > or > > ./test_progs -t xdp_bpf > test_xdp_bpf2bpf:PASS:test_xdp__open_and_load 0 nsec > test_xdp_bpf2bpf:PASS:test_xdp_bpf2bpf__open 0 nsec > test_xdp_bpf2bpf:PASS:test_xdp_bpf2bpf__load 0 nsec > libbpf: prog 'trace_on_entry': failed to attach: Device or resource busy > libbpf: prog 'trace_on_entry': failed to auto-attach: -16 > test_xdp_bpf2bpf:FAIL:test_xdp_bpf2bpf__attach unexpected error: -16 (errno 16) > #225 xdp_bpf2bpf:FAIL Urgh.. I totally missed that in flood of output. Let me go try and figure out what's happening there.