From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f74.google.com (mail-pj1-f74.google.com [209.85.216.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D88C61FAC23 for ; Mon, 21 Oct 2024 18:08:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729534135; cv=none; b=VW/4NfOheVtNfnwD3u/ganfGhOSJ1Ok4DJxfT9Sm1Pzdzl3E1ncJeeQ0bRnEKDappDMDvZmvj/XvJs78PY+TucoydGrEbQDzNq1ttsp4mupKhy9i9CUqzl+6ydU8iiJ+zTWbnmhsD558SNBdblvJm3HbWkz3LEyvLCw6Fely3z8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729534135; c=relaxed/simple; bh=lGAahFUJB47Jv0GHevlLPsXzZ4O8VtjPyAFbuGdCp8E=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=V8yxmmgUWFlSHjAU2lmMhZjNhaM9FjWJE8MNrRLyr9mgsakvFLX2PlHk7xHH/x0HWLLybt7NiEKDSR+OUMJodqGvC9RsoPbADPzKOTaNCiXHtKpIXFGSb+lSomU/2PeKQePDtQehdJVVh5qR9WAgCysYuYHu9gSYRl3Dyik4hfo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Kvy2TT4n; arc=none smtp.client-ip=209.85.216.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Kvy2TT4n" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-2e2d396c77fso6060534a91.2 for ; Mon, 21 Oct 2024 11:08:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1729534131; x=1730138931; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=B4nB5AD8jm9woOflkJu9LaOALYzY3FWUJ+pKW1FSB8o=; b=Kvy2TT4nFNRE4v6qOhuvlFoeLee0AdD4xf9oblSyYyxEb8GhQukzYNy1Ol8V+YhjMD C3NGaSmYp8oth+na2vGGhm3ih9Koiclz5KYzTxNy5pcVr9ARX+mnJ7B613cFBUpFK71x iWfh/ohEyQ3Xp1/YPlK/EY1B9iYSmr4Yc2fpQbUSrFtQAag2BJB0DTanRLhydyrkVu9O GSS75Wqwr+13Ik7si/pFv+bQ9H6zv6VW5TQn/3oPp/u1JWFq2rLcxcl9vwwiK6DdqnGd IvqPdPaVrspj8hHudi68Q1kFLiJtYZwvkWAsKsGoodfBahhHBnpIyInghyeovWvoyWBg r/Ew== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1729534131; x=1730138931; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=B4nB5AD8jm9woOflkJu9LaOALYzY3FWUJ+pKW1FSB8o=; b=ZmrKyknVnGFyR6p2kKJGf9R8PCAmAqVs40B63r2vGNW31AqhrbqcS53VxCuqLBf8Ob YjRToZ2GTOs/pW/OIS2Ymn2lkKJzdyqX2tbeV3OE1CRfRwr5F7H88g6GBJu/PmEPm8Mm USxyjzk0scIpuEFaNMf2DHKO+HYDCxeswzif4abontxtsr1GDVpFzHpnw3cHKGC53jrX OxSq2CqrfdGBKitr41Lq3DrtUgokDVO4SkhMAoggkAsD6JsK0HUgqbMcuCKyusz3CCXE 5cYQDsa0xTxUcFywzGvTyiIvz0/37ex8hOrYwJhPlRUo4OVAiV04ZDvwPpyKn9fAuj0P x9PA== X-Forwarded-Encrypted: i=1; AJvYcCXv1w79UXQg0UczN4VeMgB4zPZYRD125j1lNVcDOJ+HPU1Yse3OGOpstNJjsYvAFWKhrGaF82wvb5qiReM=@vger.kernel.org X-Gm-Message-State: AOJu0YxZjh9v5LuYw7DT6sNtUTiwYEdCQkVtxumXUBxDTkbSQ7DbDdLL VD8zDZEa557mMSUa8wVXU29hvBiKxdSfT3fa2RHRTVpUAjLPseZflrcRGMQVuBBqIGSH7ANGxwl 07g== X-Google-Smtp-Source: AGHT+IHz/sqxbIaZMzAhwQE+KHAQ50pc4vGOx7OQ/MlEMfrpYKQ16K4ySzEgLcCV5+myw9EmSbX31Z6uvf4= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:9d:3983:ac13:c240]) (user=seanjc job=sendgmr) by 2002:a17:90a:e147:b0:2d8:a9c2:2f3a with SMTP id 98e67ed59e1d1-2e5616d8f42mr22750a91.3.1729534130899; Mon, 21 Oct 2024 11:08:50 -0700 (PDT) Date: Mon, 21 Oct 2024 11:08:49 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241010182427.1434605-1-seanjc@google.com> <20241010182427.1434605-20-seanjc@google.com> Message-ID: Subject: Re: [PATCH v13 19/85] KVM: Introduce kvm_follow_pfn() to eventually replace "gfn_to_pfn" APIs From: Sean Christopherson To: Yan Zhao Cc: Paolo Bonzini , Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, "Alex =?utf-8?Q?Benn=C3=A9e?=" , David Matlack , David Stevens , Andrew Jones Content-Type: text/plain; charset="us-ascii" On Mon, Oct 21, 2024, Yan Zhao wrote: > On Thu, Oct 10, 2024 at 11:23:21AM -0700, Sean Christopherson wrote: > > --- a/virt/kvm/pfncache.c > > +++ b/virt/kvm/pfncache.c > > @@ -159,6 +159,12 @@ static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc) > > kvm_pfn_t new_pfn = KVM_PFN_ERR_FAULT; > > void *new_khva = NULL; > > unsigned long mmu_seq; > > + struct kvm_follow_pfn kfp = { > > + .slot = gpc->memslot, > > + .gfn = gpa_to_gfn(gpc->gpa), > > + .flags = FOLL_WRITE, > > + .hva = gpc->uhva, > > + }; > Is .map_writable uninitialized? Nope, per C99, "subobjects without explicit initializers are initialized to zero", i.e. map_writable is initialized to "false".