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 X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 540E7C4363A for ; Thu, 29 Oct 2020 14:47:30 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 7440B206DC for ; Thu, 29 Oct 2020 14:47:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="YOhpC2zB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7440B206DC Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id ABE704B361; Thu, 29 Oct 2020 10:47:28 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OAFrhl85+fKu; Thu, 29 Oct 2020 10:47:27 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 891084B55A; Thu, 29 Oct 2020 10:47:27 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 188AE4B545 for ; Thu, 29 Oct 2020 10:47:26 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Sy7IHzgNIHx3 for ; Thu, 29 Oct 2020 10:47:25 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id EF1BE4B361 for ; Thu, 29 Oct 2020 10:47:24 -0400 (EDT) Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9E6CE20732; Thu, 29 Oct 2020 14:47:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603982843; bh=F+HkcFc+yANZKBaSQmspmybYBo7phJrOJUMejErjoro=; h=From:To:Cc:Subject:Date:From; b=YOhpC2zB7hHKEGjddkMnjHxTi743wAmsWpMkMbVDo+Q7l2T31UQgUgpqVnyffpolD 96Uk0rS9Oa2DjimmC5slz2dqMUhL69RAUgSC+dLnjc1xvDFjF9zNtbacg6eUCBgBDB MkKEcq+ZKatazW0Oi1IgqpyYtNgaTPnSKQrvHk2A= From: Will Deacon To: kvmarm@lists.cs.columbia.edu Subject: [PATCH] KVM: arm64: Fix masks in stage2_pte_cacheable() Date: Thu, 29 Oct 2020 14:47:16 +0000 Message-Id: <20201029144716.30476-1-will@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Cc: Will Deacon , kernel-team@android.com, Marc Zyngier X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu stage2_pte_cacheable() tries to figure out whether the mapping installed in its 'pte' parameter is cacheable or not. Unfortunately, it fails miserably because it extracts the memory attributes from the entry using FIELD_GET(), which returns the attributes shifted down to bit 0, but then compares this with the unshifted value generated by the PAGE_S2_MEMATTR() macro. A direct consequence of this bug is that cache maintenance is silently skipped, which in turn causes 32-bit guests to crash early on when their set/way maintenance is trapped but not emulated correctly. Fix the broken masks by avoiding the use of FIELD_GET() altogether. Cc: Quentin Perret Reported-by: Marc Zyngier Fixes: 6d9d2115c480 ("KVM: arm64: Add support for stage-2 map()/unmap() in generic page-table") Signed-off-by: Will Deacon --- Applies on top of the other pgtable fix I previously sent here: https://lore.kernel.org/r/20201026144423.24683-1-will@kernel.org arch/arm64/kvm/hyp/pgtable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index 95141b0d6088..0271b4a3b9fe 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -635,7 +635,7 @@ static void stage2_flush_dcache(void *addr, u64 size) static bool stage2_pte_cacheable(kvm_pte_t pte) { - u64 memattr = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR, pte); + u64 memattr = pte & KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR; return memattr == PAGE_S2_MEMATTR(NORMAL); } -- 2.29.1.341.ge80a0c044ae-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm