From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6021E8C08 for ; Thu, 30 Mar 2023 17:56:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10E44C433D2; Thu, 30 Mar 2023 17:56:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680198961; bh=ETE4NkzcVBB5u4wZ7R2/Y2Ryce5KP4uPdlVqwWT7r3A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jH7mjHuAaKYiTSClO0Xw+hlx2mgYZkHRydF4zVlLMT94IaNTg+POBvwnZb4CmVM3+ UdvFE771VQ8Rq9F+PdzVn9HgoMW72SEWDONs+LUpJ9v/ZX7no2XH92EssgNBJPFwia tJswRFYkHNP/Hdxlm8Ll4w/f1o9M7AECBsmi5UTl7hyEKuWhlCcUGfzXczi9NeLuCf z041tPwrWI9iUKMSezw/FhVTlHyOv7S1LlOUo+KbjWGFExYmZfj/RUl1ODYLOT8TRT +nDKTwZsTz/iR6hPdh4mI8CgdmeoeyFqbbfNWjw33EHLKdLbHCuHKJ68EmWsT0Uyrr fZqxNrwERN72g== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1phwNc-004Rpa-Nz; Thu, 30 Mar 2023 18:48:08 +0100 From: Marc Zyngier To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Ricardo Koller , Simon Veith , Reiji Watanabe , Colton Lewis , Joey Gouly , dwmw2@infradead.org Subject: [PATCH v4 19/20] KVM: arm64: selftests: Deal with spurious timer interrupts Date: Thu, 30 Mar 2023 18:47:59 +0100 Message-Id: <20230330174800.2677007-20-maz@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230330174800.2677007-1-maz@kernel.org> References: <20230330174800.2677007-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, ricarkol@google.com, sveith@amazon.de, reijiw@google.com, coltonlewis@google.com, joey.gouly@arm.com, dwmw2@infradead.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Make sure the timer test can properly handle a spurious timer interrupt, something that is far from being unlikely. This involves checking for the GIC IAR return value (don't bother handling the interrupt if it was spurious) as well as the timer control register (don't do anything if the interrupt is masked or the timer disabled). Take this opportunity to rewrite the timer handler in a more readable way. This solves a bunch of failures that creep up on systems that are slow to retire the interrupt, something that the GIC architecture makes no guarantee about. Reviewed-by: Colton Lewis Signed-off-by: Marc Zyngier --- .../selftests/kvm/aarch64/arch_timer.c | 40 ++++++++++++------- 1 file changed, 25 insertions(+), 15 deletions(-) diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c index 26556a266021..176ab41dd01b 100644 --- a/tools/testing/selftests/kvm/aarch64/arch_timer.c +++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c @@ -121,25 +121,35 @@ static void guest_validate_irq(unsigned int intid, uint64_t xcnt = 0, xcnt_diff_us, cval = 0; unsigned long xctl = 0; unsigned int timer_irq = 0; + unsigned int accessor; - if (stage == GUEST_STAGE_VTIMER_CVAL || - stage == GUEST_STAGE_VTIMER_TVAL) { - xctl = timer_get_ctl(VIRTUAL); - timer_set_ctl(VIRTUAL, CTL_IMASK); - xcnt = timer_get_cntct(VIRTUAL); - cval = timer_get_cval(VIRTUAL); + if (intid == IAR_SPURIOUS) + return; + + switch (stage) { + case GUEST_STAGE_VTIMER_CVAL: + case GUEST_STAGE_VTIMER_TVAL: + accessor = VIRTUAL; timer_irq = vtimer_irq; - } else if (stage == GUEST_STAGE_PTIMER_CVAL || - stage == GUEST_STAGE_PTIMER_TVAL) { - xctl = timer_get_ctl(PHYSICAL); - timer_set_ctl(PHYSICAL, CTL_IMASK); - xcnt = timer_get_cntct(PHYSICAL); - cval = timer_get_cval(PHYSICAL); + break; + case GUEST_STAGE_PTIMER_CVAL: + case GUEST_STAGE_PTIMER_TVAL: + accessor = PHYSICAL; timer_irq = ptimer_irq; - } else { + break; + default: GUEST_ASSERT(0); + return; } + xctl = timer_get_ctl(accessor); + if ((xctl & CTL_IMASK) || !(xctl & CTL_ENABLE)) + return; + + timer_set_ctl(accessor, CTL_IMASK); + xcnt = timer_get_cntct(accessor); + cval = timer_get_cval(accessor); + xcnt_diff_us = cycles_to_usec(xcnt - shared_data->xcnt); /* Make sure we are dealing with the correct timer IRQ */ @@ -148,6 +158,8 @@ static void guest_validate_irq(unsigned int intid, /* Basic 'timer condition met' check */ GUEST_ASSERT_3(xcnt >= cval, xcnt, cval, xcnt_diff_us); GUEST_ASSERT_1(xctl & CTL_ISTATUS, xctl); + + WRITE_ONCE(shared_data->nr_iter, shared_data->nr_iter + 1); } static void guest_irq_handler(struct ex_regs *regs) @@ -158,8 +170,6 @@ static void guest_irq_handler(struct ex_regs *regs) guest_validate_irq(intid, shared_data); - WRITE_ONCE(shared_data->nr_iter, shared_data->nr_iter + 1); - gic_set_eoi(intid); } -- 2.34.1