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 83A33C433FE for ; Tue, 23 Nov 2021 13:52:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235599AbhKWNzz (ORCPT ); Tue, 23 Nov 2021 08:55:55 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:20322 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230134AbhKWNzy (ORCPT ); Tue, 23 Nov 2021 08:55:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1637675565; 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=hg3rpdgYxxcOBJc5G9ynr2yksQKyjRICI2KgG4YRajw=; b=KK7H/zCirjKHQ0vDA9ej11lu6jweZUQD7SGd7cZ4hlGnkM6h6vRMik97ZGX4A3cnWb2EDV 1w1Ucv9ZCNjHSjC8t2LmMwl11G+kdkjJ5bU815K5O+muen7rf85YwMYMdxQJres5oJPTby laCdp+LkAVtyDUc07ypKV79hI1EA5KM= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-368-oqUsUDXTPH6qvOzrt1vxRA-1; Tue, 23 Nov 2021 08:52:44 -0500 X-MC-Unique: oqUsUDXTPH6qvOzrt1vxRA-1 Received: by mail-wm1-f71.google.com with SMTP id a64-20020a1c7f43000000b003335e5dc26bso2909655wmd.8 for ; Tue, 23 Nov 2021 05:52:43 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=hg3rpdgYxxcOBJc5G9ynr2yksQKyjRICI2KgG4YRajw=; b=HdZ9+sRWSLvPsNqKmMmsZ2VogWEs9uk4PL0LlyFdKwZAgpz+qrv2Z4az1/3MoOG78C MVw63Z4pIEaX1ZYnvxGSUed0Qk0gUwgo9qcHdshEXbJ4k+GphhCduRq55kQmD0AYTKff hAAL215lGnvSQxiE3jgJ3honaGwH0OzYr60SekW5tFSFDuOtMOh5r1D18rF06yMMKSL/ v5hid+p0tzw06fzn8+M5Cgh+EXlrbAd+lMSVNKgJ1tqjKRklAz4FXjeR1fg5ZtE8qQPV QcdNQUgptBIVqpA4TBPFZR1UFh3xQoIJN6KvrTxAjhK95l2wfJ4DweyCZhKABP6RiJNy I1FA== X-Gm-Message-State: AOAM531HAc4eoCXIhBrJyVMub6U8HE0rGbbg2g9EYTGGUj1Cpa8OP1l4 8/z417tEdZN61RSqbnGCSIbT49mJOddGJaJ4XXEmhelUfxOYuWyivMyczA9ZaYodhMC93dmuEfX yRE+2k9LCJYZKYsK3h2txKfHVW6ESTU1Z6zBuV+5Ic/XC7L1khJpTvRSbZ3Ic8Fjn1CmRMvtGI5 3m X-Received: by 2002:a1c:7e04:: with SMTP id z4mr3279220wmc.134.1637675562950; Tue, 23 Nov 2021 05:52:42 -0800 (PST) X-Google-Smtp-Source: ABdhPJw7iTjEl+nEyfMdplA1sJxP2OTCbcZNTVWZJYf4xKxVJgZBJzKPzNLaMH3ChCLer/E4VRC5uQ== X-Received: by 2002:a1c:7e04:: with SMTP id z4mr3279190wmc.134.1637675562732; Tue, 23 Nov 2021 05:52:42 -0800 (PST) Received: from fedora (g-server-2.ign.cz. [91.219.240.2]) by smtp.gmail.com with ESMTPSA id o1sm12066278wrn.63.2021.11.23.05.52.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Nov 2021 05:52:42 -0800 (PST) From: Vitaly Kuznetsov To: Sean Christopherson Cc: kvm@vger.kernel.org, Paolo Bonzini , Wanpeng Li , Jim Mattson , linux-kernel@vger.kernel.org Subject: Re: [PATCH] KVM: selftests: Make sure kvm_create_max_vcpus test won't hit RLIMIT_NOFILE In-Reply-To: <87czmsm5iv.fsf@redhat.com> References: <20211122171920.603760-1-vkuznets@redhat.com> <87czmsm5iv.fsf@redhat.com> Date: Tue, 23 Nov 2021 14:52:41 +0100 Message-ID: <877dczm11y.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Vitaly Kuznetsov writes: >>> >>> + /* >>> + * Creating KVM_CAP_MAX_VCPUS vCPUs require KVM_CAP_MAX_VCPUS open >>> + * file decriptors. >>> + */ >>> + TEST_ASSERT(!getrlimit(RLIMIT_NOFILE, &rl), >>> + "getrlimit() failed (errno: %d)", errno); >> >> And strerror() output too? >> > > Sure, will add in v2. > Actually, there are two issues with the code above. First, TEST_ASSERT() already prints both errno and strerror() (setrlimit() counterpart which is easier to make fail): KVM_CAP_MAX_VCPU_ID: 4096 KVM_CAP_MAX_VCPUS: 1024 ==== Test Assertion Failure ==== kvm_create_max_vcpus.c:68: !setrlimit(RLIMIT_NOFILE, &rl) pid=344504 tid=344504 errno=1 - Operation not permitted 1 0x0000000000402485: main at kvm_create_max_vcpus.c:68 2 0x00007fcb2e8b4041: ?? ??:0 3 0x000000000040254d: _start at ??:? setrlimit() failed, errno: 0 Second, note "errno: 0" above. There's no guarantee that getrlimit() will be executed before evaluating 'errno' in C. I think I'll just drop redundant errno printout then. -- Vitaly