From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (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 BD75730FA6 for ; Tue, 3 Oct 2023 20:58:47 +0000 (UTC) Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-27763c2c27dso1095555a91.2 for ; Tue, 03 Oct 2023 13:58:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1696366727; x=1696971527; darn=lists.linux.dev; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=ofK3yTXudgH3dPOX+NXSBZm32mvv1GbIdTLu5eO4ZUw=; b=yrLZ1rOElxQdBjdwRBNajH55Ndz59pPU/2JOtE3QT++TKsJtz06m8ui0QXw6YiYKL0 3hWo+QZg+rFyoRdxMh8kzrO6SSW4cSRistfl0+B+Ug4dKQC9D/fTcMwCrB0EbCiVf1PB 7AxkD3w0cz54XymV7ImbF/uJKgxjB6QAgcu0/u5rMrt2kkH/XLK11OH8sI+I4aio+HJW OZFQzuTHiXsYF287BjXHsE99iy4gQFlnJj6Wr66MYHeO5EjC09yUZrquTQJnU+RkMPpa 8R6HYkYWE/up8y9U2RPBmjVubxzkemosJ9UV2XI1i3XEqpZBSFLsXVihwAQBUQ15H4lW JTig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696366727; x=1696971527; h=content-transfer-encoding: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=ofK3yTXudgH3dPOX+NXSBZm32mvv1GbIdTLu5eO4ZUw=; b=MIHStdf0QmtEWa4Dghp0UvRH1QPfC+krgKJbg4IknV7WBqHGh65LdCsJ/Vtm84V4aT YPApJYFNHG82JFdNsO1nxpUXx4aLh9FMt8zCKzDNtndnoHsT4Eq8R0YuRnAd8hEsHmsR 15k3X3d8LETs66gs5bILgnUJ9i142nlGiPHbx50jqzVkbmxf7Mp/Io547HKTvxaGpZJh xQUIwSD4zG64l2fEAjp1mszeA5YchlSa49m7Fg0o0PkR1UzJcy/2jvobh2YBoQ5JKyBS txecIvxmeH6rfiKy/+0PgkoXgKal0k+TEMe4BSDn2OvI0dblHX/rLGFIgQw349/gnzJS jDfw== X-Gm-Message-State: AOJu0Ywqy/ZK/pr6JIwGCdfvNwaXvq13cTykEBiQDKHT8/dSljsW6h+b aqZ0J7FAUeMLCp8QXI4Ksqf0OCF03/o= X-Google-Smtp-Source: AGHT+IEpJRqfisemR4Ma6/26idPCJUHwNJZNRJlSNji243dfZdo+DGHvKt5onPD5NiiwHo9l66/HVhcVsls= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:90b:92:b0:26d:ae3:f6a4 with SMTP id bb18-20020a17090b009200b0026d0ae3f6a4mr6815pjb.5.1696366727020; Tue, 03 Oct 2023 13:58:47 -0700 (PDT) Date: Tue, 3 Oct 2023 13:58:45 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20230911021637.1941096-1-stevensd@google.com> <20230911021637.1941096-6-stevensd@google.com> Message-ID: Subject: Re: [PATCH v9 5/6] KVM: x86: Migrate to __kvm_follow_pfn From: Sean Christopherson To: Maxim Levitsky Cc: David Stevens , Yu Zhang , Isaku Yamahata , Zhi Wang , kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Tue, Oct 03, 2023, Maxim Levitsky wrote: > =D0=A3 =D0=BF=D0=BD, 2023-09-11 =D1=83 11:16 +0900, David Stevens =D0=BF= =D0=B8=D1=88=D0=B5: > > From: David Stevens > > @@ -4283,12 +4290,20 @@ static int __kvm_faultin_pfn(struct kvm_vcpu *v= cpu, struct kvm_page_fault *fault > > return RET_PF_EMULATE; > > } > > =20 > > - async =3D false; > > - fault->pfn =3D __gfn_to_pfn_memslot(slot, fault->gfn, false, false, &= async, > > - fault->write, &fault->map_writable, > > - &fault->hva); > > - if (!async) > > - return RET_PF_CONTINUE; /* *pfn has correct page already */ > > + foll.flags |=3D FOLL_NOWAIT; > > + fault->pfn =3D __kvm_follow_pfn(&foll); > > + > > + if (!is_error_noslot_pfn(fault->pfn)) > > + goto success; > Unrelated but I can't say I like the 'is_error_noslot_pfn()' name,=20 > I wish it was called something like is_valid_pfn(). I don't love the name either, but is_valid_pfn() would be extremely confusi= ng because the kernel already provides pfn_valid() to identify pfns/pages that= are managed by the kernel. Trying to shove "guest" somewhere in the name also = gets confusing because it's a host pfn, not a guest pfn.