From nobody Sun Feb 8 23:23:25 2026 Received: from mail-ed1-f73.google.com (mail-ed1-f73.google.com [209.85.208.73]) (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 3FD78238D35 for ; Fri, 7 Feb 2025 14:54:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738940087; cv=none; b=jMvmC6D77Wbm405uGuWoaxV4kyFqwNZDNgQA6ERUTkZi9AYEA28LupF+gsde30FU05A9+aSHqOYeBjw4Y4wSPle5UU4BIu0A2J66oy7vGfj5XKL615JvF83mbfR2NeS5mS7EVjP3bLZi4JqJ8/NIqbQBajL4AJ2mY2URlLhSzIo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738940087; c=relaxed/simple; bh=ZCRFTCY1hi3XMbgWbwzaOADq8bLynRa5HB5rf6QanHA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=fl0f5qgmVqdKggwZMya9k6GIOT88/J98eFzutmk6qckjMlpaewqlx526XHlpsBHYAFFYmpiZd9pzx/bQ2MAZDL7qZPxQjw4pYawDqiP6MLsMI9JbrhcRBX6igVkfOM5n3XTroCKLl53RbpsPC+1vz+4Bd/QtYA/kqDvZjZd1sEs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--qperret.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=XCWH+U6n; arc=none smtp.client-ip=209.85.208.73 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--qperret.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="XCWH+U6n" Received: by mail-ed1-f73.google.com with SMTP id 4fb4d7f45d1cf-5de573292e7so103773a12.1 for ; Fri, 07 Feb 2025 06:54:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1738940083; x=1739544883; 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=QlxUuvHn55P4VJoa3VPKXet3o2roscTj71cLK/0XsCo=; b=XCWH+U6nLMubKCsEzoQx7/nyy+x16f0+2kISo1G9QCXjSNOr8cMCswcANMxQBBxx1g KqH9pwkngKuJPKDJP/jQOvLG/umj48pVnQ5uodt0ZIW3z4lZVIsclEyf9Ne3mWo58zgE fLngrGq4svFcgY8Z/4rYJbkginJgQV9QQsMvkQUR6oNfwXcf0xduZXK2St+EUxSzCd3m 6rkIz1xogPFSp8GAYbxHY/sYlWkWRJuSz8vBrUuOlgIMJRACZ3bUAKQ+MwnjbbGs/TnO cHRFcDp1m0R2h4t1Fc/ozdkdS0/k4vJgYmnoO9k4cdfSjrGgwt3ReZ15MLocnwlWTxu/ +vhQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738940083; x=1739544883; 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=QlxUuvHn55P4VJoa3VPKXet3o2roscTj71cLK/0XsCo=; b=d/xkDVMNniJe049806jmTDW/OSJ92pNlyLXq9LYqi0EhUeeq1hV5uNC0u4cqNOxJH7 mc9zITSNQVmpL2k/nUPv1P5pGnqozLSVFuIIUIG0qMThoTbt7MmgNmPgphc/EZ8nBefy bD1qHRQsL2QwDYD0emX2dYUN/1vN6g2U17j5CrxxWBpHUeHUtEr/ATlcF6Va1V+OyaVh asZuv8Fl14+FhSJwVCd9jU/H1O5g4hyEXJIDb0p8VB/Dh8wpI+tEw9dzLB7XB+UNHpsS 4AX6IFXEWUjpWAHdWcB0VtRD5/cldOHAuGwiYs5fE9Wu4hDk/hbK165ZYaxB14nP8eHA 2z5w== X-Forwarded-Encrypted: i=1; AJvYcCUMn+ZZ95CdMw2yuQKjuzqu2QhSL7eaOeMWExjX8ZX67qQ7oy3eGeDQLZ79/nVo05DCq8zyE/z4X5zK9fs=@vger.kernel.org X-Gm-Message-State: AOJu0Yz+pOC/pfKWKEAQoS/em+/WtkAO+LFqHtBUhXyN+ew3DE/LnBlA 7JgvYKN5bJP1Iq7Eyo6pCDgoCL+OJ1Z1UyZd1ixye48MRYmtfA5RVqg2gdK2GxvfCR7LDAwj9yl 0JtWuNA== X-Google-Smtp-Source: AGHT+IEuPMCv7YqXJlNHwKccMEWSYS/+UUaEr2aDY+SyLUIdyjbcKQ2U586hKi+BCjLaIqvUPKXUd5QYm4sG X-Received: from edax2.prod.google.com ([2002:a05:6402:4142:b0:5dc:110c:e5e2]) (user=qperret job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:2546:b0:5d9:f21a:aa26 with SMTP id 4fb4d7f45d1cf-5de450a9e4cmr3320543a12.24.1738940083729; Fri, 07 Feb 2025 06:54:43 -0800 (PST) Date: Fri, 7 Feb 2025 14:54:37 +0000 In-Reply-To: <20250207145438.1333475-1-qperret@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250207145438.1333475-1-qperret@google.com> X-Mailer: git-send-email 2.48.1.502.g6dc24dfdaf-goog Message-ID: <20250207145438.1333475-2-qperret@google.com> Subject: [PATCH 1/2] KVM: arm64: Improve error handling from check_host_shared_guest() From: Quentin Perret To: Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon Cc: Fuad Tabba , Vincent Donnefort , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The check_host_shared_guest() path expects to find a last-level valid PTE in the guest's stage-2 page-table. However, it checks the PTE's level before its validity, which makes it hard for callers to figure out what went wrong. To make error handling simpler, check the PTE's validity first. Signed-off-by: Quentin Perret --- arch/arm64/kvm/hyp/nvhe/mem_protect.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvh= e/mem_protect.c index 7ad7b133b81a..41847c04b270 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -943,10 +943,10 @@ static int __check_host_shared_guest(struct pkvm_hyp_= vm *vm, u64 *__phys, u64 ip ret =3D kvm_pgtable_get_leaf(&vm->pgt, ipa, &pte, &level); if (ret) return ret; - if (level !=3D KVM_PGTABLE_LAST_LEVEL) - return -E2BIG; if (!kvm_pte_valid(pte)) return -ENOENT; + if (level !=3D KVM_PGTABLE_LAST_LEVEL) + return -E2BIG; =20 state =3D guest_get_page_state(pte, ipa); if (state !=3D PKVM_PAGE_SHARED_BORROWED) --=20 2.48.1.502.g6dc24dfdaf-goog