From patchwork Mon Apr 4 18:21:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Upton X-Patchwork-Id: 12800597 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6EBF8C433F5 for ; Mon, 4 Apr 2022 18:22:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:From:Subject:References: Mime-Version:Message-Id:In-Reply-To:Date:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=Tsm9oAJRfTGhObb0p70txFJxKDxvDm5/yFyJSRHwihk=; b=3W7FjqhlxkHkP1jyz3IZhMZHxW LkFM2+wt5ZZMJU8O4Lu5k1MQSzoHfvGx4/ojGh8Oj6+jU+Js5/NOu/O0ywuaSGRuv7hyLYkIcf1U+ 8kk++hmGK00UW2YcAMo1r67PxmBBkvFU6urYmnlUdQC7u5Bmc1ry2a1WZ7xjp2fmITd2s6FJ8AEla +95ji7dyvi1IDh4ZPcT/H+eAhOEke6XbLkbx+dz5fUl0Id9GhCxanBQVW8OrrUJ3V3ikbLvSdvTD9 bZ6Jqx2Pa3qVCK9VcTTbRMgp73uXdTztJKN/YV1pCo4C4Ld5jvrq1R0ZpW6Y0XoJs6Al90qTTNh6H 1KuqWOBA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nbRKn-00G7DR-DK; Mon, 04 Apr 2022 18:21:49 +0000 Received: from mail-io1-xd49.google.com ([2607:f8b0:4864:20::d49]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nbRKV-00G7Am-Od for linux-arm-kernel@lists.infradead.org; Mon, 04 Apr 2022 18:21:33 +0000 Received: by mail-io1-xd49.google.com with SMTP id h14-20020a05660208ce00b00645c339411bso6837824ioz.8 for ; Mon, 04 Apr 2022 11:21:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=UF2I2mHbDVASrG05DEItZfczKpOZthJZ1m0MB3YjXVY=; b=tcxC71n8qRIQtoplY54rvL/t1PM0vquhFBE/lAZhF7XYLojblaLlklu7pRZ9UPnz2y 1DCwD3eahwdyYR2x+Ew8gFONkQgrmXFyMrYjaAedHmdyKQpBNUDi7wvucA2nf0RRP4yj 8OjE3G6p/9MKRMB/fxfL3GKqq53KeK6h/oL30r8siKj45GroFMnBACt2kw/jhcfQdX1P 974RrKtOT0HPojjuNUxVR1SbbTgex41Y1OzCalE1p4ke0cTnIXpM+TDnXprsmKu77tq2 TagfXw6GPklrVI7x9HWxjeG8KMzXtBHH0KsZRB90fzH0AifnWI5EC/CBe2S2gKzQjerQ GO9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=UF2I2mHbDVASrG05DEItZfczKpOZthJZ1m0MB3YjXVY=; b=Tm/8ar6trSK43BQfdR4HpQfl5V8UCBaSGQcaN6Q8oNh4wuhfPTLiY2iPSvNZOjYOPe xIsmIWDUHJoyFX8+V64m54qb94glnIMB72/kDTY8yTlQPVrP5+ZR4Pn9OFpCtL1oIjEZ 8VWTSdGm34An94GMjLB8o/In+0/qx3yf9rGthDn09ZjpOo/0ZQUy5njhoSZ02vq3vEjd TW4dTP0j1tmm3C9WuurSPlYEo2ZbdA/KMFl9YcbwiuxW43ZbVklMxuThQ9YKnDE3pHT8 uiwmfjzm7RvwB5L8KzKTsFIzJF2SXiUgLcOmSIDg727TVmOFgAt0ozdyrQeQIfQr/m+n CKHg== X-Gm-Message-State: AOAM531orI6u21KPAGTxnxWd3AiZF4yKyh3JuBye5y875wbmlkZZ2V8G poT3MKw2U6D8d5B7hLG+ybGWY3f39yA= X-Google-Smtp-Source: ABdhPJxMtg0K6INoCkIU+22+KIhOsbvZj/wp5fDFQBYNYjykIapUx1/xqAWiebo8OINm+4A3zMI6PtlF6Z0= X-Received: from oupton.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:404]) (user=oupton job=sendgmr) by 2002:a5d:81d4:0:b0:649:ac07:27b with SMTP id t20-20020a5d81d4000000b00649ac07027bmr688893iol.216.1649096490046; Mon, 04 Apr 2022 11:21:30 -0700 (PDT) Date: Mon, 4 Apr 2022 18:21:18 +0000 In-Reply-To: <20220404182119.3561025-1-oupton@google.com> Message-Id: <20220404182119.3561025-3-oupton@google.com> Mime-Version: 1.0 References: <20220404182119.3561025-1-oupton@google.com> X-Mailer: git-send-email 2.35.1.1094.g7c7d902a7c-goog Subject: [PATCH v2 2/3] selftests: KVM: Don't leak GIC FD across dirty log test iterations From: Oliver Upton To: kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org, Marc Zyngier , James Morse , Alexandru Elisei , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, Peter Shier , Ricardo Koller , Reiji Watanabe , Paolo Bonzini , Sean Christopherson , Oliver Upton , Jing Zhang X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220404_112131_879076_28A7AD48 X-CRM114-Status: GOOD ( 16.40 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org dirty_log_perf_test instantiates a VGICv3 for the guest (if supported by hardware) to reduce the overhead of guest exits. However, the test does not actually close the GIC fd when cleaning up the VM between test iterations, meaning that the VM is never actually destroyed in the kernel. While this is generally a bad idea, the bug was detected from the kernel spewing about duplicate debugfs entries as subsequent VMs happen to reuse the same FD even though the debugfs directory is still present. Abstract away the notion of setup/cleanup of the GIC FD from the test by creating arch-specific helpers for test setup/cleanup. Close the GIC FD on VM cleanup and do nothing for the other architectures. Fixes: c340f7899af6 ("KVM: selftests: Add vgic initialization for dirty log perf test for ARM") Reviewed-by: Jing Zhang Signed-off-by: Oliver Upton --- .../selftests/kvm/dirty_log_perf_test.c | 34 +++++++++++++++++-- 1 file changed, 31 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c index c9d9e513ca04..7b47ae4f952e 100644 --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c @@ -18,11 +18,40 @@ #include "test_util.h" #include "perf_test_util.h" #include "guest_modes.h" + #ifdef __aarch64__ #include "aarch64/vgic.h" #define GICD_BASE_GPA 0x8000000ULL #define GICR_BASE_GPA 0x80A0000ULL + +static int gic_fd; + +static void arch_setup_vm(struct kvm_vm *vm, unsigned int nr_vcpus) +{ + /* + * The test can still run even if hardware does not support GICv3, as it + * is only an optimization to reduce guest exits. + */ + gic_fd = vgic_v3_setup(vm, nr_vcpus, 64, GICD_BASE_GPA, GICR_BASE_GPA); +} + +static void arch_cleanup_vm(struct kvm_vm *vm) +{ + if (gic_fd > 0) + close(gic_fd); +} + +#else /* __aarch64__ */ + +static void arch_setup_vm(struct kvm_vm *vm, unsigned int nr_vcpus) +{ +} + +static void arch_cleanup_vm(struct kvm_vm *vm) +{ +} + #endif /* How many host loops to run by default (one KVM_GET_DIRTY_LOG for each loop)*/ @@ -206,9 +235,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) vm_enable_cap(vm, &cap); } -#ifdef __aarch64__ - vgic_v3_setup(vm, nr_vcpus, 64, GICD_BASE_GPA, GICR_BASE_GPA); -#endif + arch_setup_vm(vm, nr_vcpus); /* Start the iterations */ iteration = 0; @@ -302,6 +329,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) } free_bitmaps(bitmaps, p->slots); + arch_cleanup_vm(vm); perf_test_destroy_vm(vm); }