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 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 7DACBC982FA for ; Wed, 23 Sep 2026 13:00:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc: To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=bygnlyduWNX9bGl+OAOhRpG2bzPfJz7Wo7gATpHhbZ0=; b=krRLKqLlAoty1NMRHVb375dFAx LMPJPUfIZ2luXW5nqMLL2ox+zP5EssiFaiEJh/YjMxzzh/c/Wri3qBG1csjwkbUYYBsrqqBnQrLmo tw+DUsxcfauWtMmdFCZ6qY4Vu8ETP4Tl9+5jiJxl5NfO6oTYx8IUKuqXxJ2fAgelzPJW2FINYOWu6 ttBTnjO4vbgpR8Rx/KxjC04hENBIdj2xvTWbGS9aZfrsNOsO60zFsdwY+ZHWzc2nX50dgY6X9du1A lq/bMsbRWXubyQr63UH/GIhU5Uhc+l6oIGARAGmz52qAiOq+jvUCpw6PTclRnxfydAdMqwh1TGXjj J47rlDZw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x9MaC-00000008KBk-3Jk8; Wed, 23 Sep 2026 13:00:20 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x9MaA-00000008KB6-03KR for linux-arm-kernel@lists.infradead.org; Wed, 23 Sep 2026 13:00:18 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 27BF1601FB; Wed, 23 Sep 2026 13:00:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B46E81F000FF; Wed, 23 Sep 2026 13:00:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790168416; bh=bygnlyduWNX9bGl+OAOhRpG2bzPfJz7Wo7gATpHhbZ0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=GSejrNXcWpOIhzmDIgz77w5u8mRJlnIHTcFuakWa+LN4RJ/GWzRCYCTlaKyEaF6qh PFH8GvS+RkCjHo3jXbZ85iR5PV3EJt52wNg798gUdjROejL9ssUTX6aNMzk/MHy2+U IzZ+xAtk2Ph9TZJ6mtcCLJV2GjYWOF2T0LmrddSAfa1Ug6MlPcTxwYcAg8ZS+pIn0x zb4NoK17FNt7tZcwSLyBA6ylQD9yDixwXpDn71N+jWgTXUG+WX30ry0KJ/HXt9yA4x DGDOAt+Oobz74m4tH66qILPGlbrizeNTrHE1A8RS+MZB4Y5sMBkw9/yBr0uIIA97qB ArMpJjI90PiAQ== From: Will Deacon To: Catalin Marinas , Fuad Tabba Cc: mark.rutland@arm.com, kernel-team@android.com, Will Deacon , Marc Zyngier , Anshuman Khandual , Rob Herring , James Clark , Jonathan Corbet , Randy Dunlap , Shuah Khan , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] arm64/boot: Disable trapping of PMZR_EL0 writes to EL2 Date: Wed, 23 Sep 2026 14:00:05 +0100 Message-ID: <179016687079.3278822.12341361045842371613.b4-ty@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260922181430.3532371-1-fuad.tabba@linux.dev> References: <20260922181430.3532371-1-fuad.tabba@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit 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 On Tue, 22 Sep 2026 19:14:30 +0100, Fuad Tabba wrote: > __init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2. > PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in > HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host > traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The > kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU > driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a > write from EL0 reaches the trap and takes the host down without a panic > message. > > [...] Applied to arm64 (for-next/fixes), thanks! [1/1] arm64/boot: Disable trapping of PMZR_EL0 writes to EL2 https://git.kernel.org/arm64/c/2bc6b218717b Cheers, -- Will https://fixes.arm64.dev https://next.arm64.dev https://will.arm64.dev