From patchwork Tue Oct 8 16:01:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 11179821 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5D22D18B7 for ; Tue, 8 Oct 2019 16:01:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 33E38217D7 for ; Tue, 8 Oct 2019 16:01:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570550518; bh=hKiwaJhVxCSiCRF1bXZhTDlIgr8qrLaf2A0Ts8wmUUo=; h=From:To:Cc:Subject:Date:List-ID:From; b=SQ0QZGB4XXNzxB6pxb8EpA0gzsJnJuD4YtR7b5JyeySOVm0eyE5mL+aWMOBhRD9ow vChPcI6ntFobjoKsIWLuhlOs1VNCo8XJn681FjAWIhwPqFt0DgObpTZHztuaOdtnBC vFhFjrjKxHzwfDvClzPuytddcuB1jxPiVUD9qePI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728459AbfJHQB5 (ORCPT ); Tue, 8 Oct 2019 12:01:57 -0400 Received: from inca-roads.misterjones.org ([213.251.177.50]:54549 "EHLO inca-roads.misterjones.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727970AbfJHQB5 (ORCPT ); Tue, 8 Oct 2019 12:01:57 -0400 Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by cheepnis.misterjones.org with esmtpsa (TLSv1.2:DHE-RSA-AES128-GCM-SHA256:128) (Exim 4.80) (envelope-from ) id 1iHrvs-0001rs-DQ; Tue, 08 Oct 2019 18:01:52 +0200 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Cc: Will Deacon , Mark Rutland , James Morse , Julien Thierry , Suzuki K Poulose , Andrew Murray Subject: [PATCH v2 0/5] KVM: arm64: Assorted PMU emulation fixes Date: Tue, 8 Oct 2019 17:01:23 +0100 Message-Id: <20191008160128.8872-1-maz@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, will@kernel.org, mark.rutland@arm.com, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, andrew.murray@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on cheepnis.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org I recently came across a number of PMU emulation bugs, all which can result in unexpected behaviours in an unsuspecting guest. The first two patches already have been discussed on the list, but I'm including them here as part of a slightly longer series. The third patch is new as of v2, and fixes a bug preventing chained events from ever being used. The fourth patch is also new as of v2, and is an arm64 PMU change for which I clearly don't know what I'm doing. I'd appreciate some guidance from Will or Mark. The last patch fixes an issue that has been here from day one, where we confuse architectural overflow of a counter and perf sampling period, and uses patch #4 to fix the issue. I'l planning to send patches 1 through to 3 as fixes shortly, but I expect the last two patches to require more discussions. Marc Zyngier (5): KVM: arm64: pmu: Fix cycle counter truncation arm64: KVM: Handle PMCR_EL0.LC as RES1 on pure AArch64 systems KVM: arm64: pmu: Set the CHAINED attribute before creating the in-kernel event arm64: perf: Add reload-on-overflow capability KVM: arm64: pmu: Reset sample period on overflow handling arch/arm64/include/asm/perf_event.h | 4 +++ arch/arm64/kernel/perf_event.c | 8 ++++- arch/arm64/kvm/sys_regs.c | 4 +++ virt/kvm/arm/pmu.c | 45 +++++++++++++++++++---------- 4 files changed, 45 insertions(+), 16 deletions(-)