From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 73E62174EE5 for ; Thu, 30 May 2024 11:24:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717068247; cv=none; b=gHDxFb3QinGNAT5ab7xl4fuOf4uRczI3AhKBBHpewSWC1TOR1Vzvpu4MxVpKiICF7Vh/xLZw6NV8/srOklAaTVSEQKMlo3sRqRrQ+oHz+GDRWGikweSo8S7rEieX7ivXL2HBWHhvhpjAdsB30dmEW9fYaqZNl702MDiCiznmla0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717068247; c=relaxed/simple; bh=IbiAcFEwpuYaFXmkBXJwg3JefhvhU9je+ScUl5D7G2c=; h=Date:From:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=QoQZAlhHd+GVcs6Ut+EjAZOk/09BSiUu52hR7cKjQkisH4wKMr3/QOk1+NIvlOofheZGPuoKxTqRCIKdqBrFYv7ciw9R3YQMmJOPhn8ydfET/NmYUqMZWDTjGRnk/jGW6edL/hgMMnZ6oQ0vp4+vovYEWtmnMQYbptXm3vEmGJE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=PaESKfPj; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="PaESKfPj" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1717068245; 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=NyFVukIA+6eMErT5jIwX1F/VfLDC/ji7PYywadLXOr0=; b=PaESKfPjSj0XtZvCY38ak9BVj5r994j9GsTQI433VquhQu+OwX0sTvAnR36U8joCD6f1mJ UpxQPyce0+L8jHpLStpfvmPoMu89n/QDabOBturmDQ6wZqb0c6EE8wrnoJIuBFqUKKMtOm 7tEEAIYPhhjWEfo0+XgJBkYG3pVtfZw= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-631-ViP1YuCJNY2QNcqsyce-yQ-1; Thu, 30 May 2024 07:24:03 -0400 X-MC-Unique: ViP1YuCJNY2QNcqsyce-yQ-1 Received: by mail-wr1-f69.google.com with SMTP id ffacd0b85a97d-35dcb3f1ab3so239744f8f.0 for ; Thu, 30 May 2024 04:24:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1717068243; x=1717673043; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=NyFVukIA+6eMErT5jIwX1F/VfLDC/ji7PYywadLXOr0=; b=nix7P9O03c+ELQ7/1qhgUeFPGRKpgr8WtD56/3hMvIYw2aX5Ml5uqsYPrNqu4O6BnB JCi8XpwoC++BiMglVAvie+KfM8PRerjNYaKQTtGLxcjNzPKqtWh4eemofGLF285hWkwp HyQ+4gNTGjAi18cs9QL5ng3KFo7G2YWXGLvi64lzoBwrnr4ezi3ESCTHN38xMfx0jGff do2/0tie1oKkpruB6s2IebhnPLL7SQFhuddfXmZnzCPEONfpE0Vb2W1rPA56nz2FEBeS f5TS6BaS8xUbPRrmvglHxVRweDjPWl+SJ3MuFi12xPPs6qRon6iSFMiQOdNXDj35qN1r LvMQ== X-Forwarded-Encrypted: i=1; AJvYcCUhgQ2JHga7yXAgoJIy/O4PVxIw30DjFZ2A19eCYKdJKbeUbnevyg95qaJOoWbGW0X3JZbf1llI1xXWs3zBHK7WIGZBfUhOZrnviD3z X-Gm-Message-State: AOJu0YypK1n+DPjFgdreIA0/Mf8GrYfoSrCxzExlt+bu2PQ/uR7yFuKa SnXw6QmdramEQRnqTYgwNBx8JZVV7iQtIVwXRlFrJ6QUfRjN+CgWh45VeTS+NjisZgMXNL55VQZ 7JahlbbGAUDH8ISPRH1P0B4/t9XFScAjWw4F3sHa+3xgeJ+/YXFjxfN8MrVaZYg== X-Received: by 2002:adf:ef0c:0:b0:357:ce05:7533 with SMTP id ffacd0b85a97d-35dc0099613mr1211458f8f.40.1717068242864; Thu, 30 May 2024 04:24:02 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGOLwH0ZFTriyl8uzTdycdGfXdQu8TChCl2APlRFv5WkN/IIPx8ecBsis+IyjdEMOUVvO8E2A== X-Received: by 2002:adf:ef0c:0:b0:357:ce05:7533 with SMTP id ffacd0b85a97d-35dc0099613mr1211444f8f.40.1717068242417; Thu, 30 May 2024 04:24:02 -0700 (PDT) Received: from rh (p200300c93f02d1004c157eb0f018dd01.dip0.t-ipconnect.de. [2003:c9:3f02:d100:4c15:7eb0:f018:dd01]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3579354abd1sm13832465f8f.59.2024.05.30.04.24.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 May 2024 04:24:02 -0700 (PDT) Date: Thu, 30 May 2024 13:24:01 +0200 (CEST) From: Sebastian Ott To: Eric Auger cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Catalin Marinas , Will Deacon Subject: Re: [PATCH v3 2/6] KVM: arm64: maintain per VM value for CTR_EL0 In-Reply-To: <2dcfc174-9384-4746-833d-1442bcfb6d11@redhat.com> Message-ID: References: <20240514072252.5657-1-sebott@redhat.com> <20240514072252.5657-3-sebott@redhat.com> <90e53cc7-039f-5abc-f94c-cf53a1602a2a@redhat.com> <2dcfc174-9384-4746-833d-1442bcfb6d11@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="-1463795790-1183132592-1717068242=:11201" This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. ---1463795790-1183132592-1717068242=:11201 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8BIT On Wed, 29 May 2024, Eric Auger wrote: > On 5/29/24 17:51, Sebastian Ott wrote: >> On Wed, 29 May 2024, Eric Auger wrote: >>>> @@ -3557,6 +3557,13 @@ void kvm_reset_sys_regs(struct kvm_vcpu *vcpu) >>>>      struct kvm *kvm = vcpu->kvm; >>>>      unsigned long i; >>>> >>>> +    if (!kvm_vcpu_initialized(vcpu)) >>> at this stage of the reading, why is the above check needed? >> >> To make sure that a later call to this function doesn't overwrite >> the value provided by userspace. (See e016333745c "KVM: arm64: Only >> reset vCPU-scoped feature ID regs once"). > but isn't it overwritten through the .reset=reset_ctr() that is > populated in next patch? No, this is done via reset_vcpu_ftr_id_reg() and also guarded by kvm_vcpu_initialized(). Sebastian ---1463795790-1183132592-1717068242=:11201--