From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 96230606A321 for ; Fri, 30 Oct 2026 11:42:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=e9CVNdJa; dkim=pass (1024-bit key, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=XIVYestp DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc: To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=r6oWs9NRS8dj5BRdE3SOboRlekQH4GrocVOda0uMj/o=; b=e9CVNdJaXT6hPN bGMlOVZaA2xJTRJJqNCr4rrGQfjX56nKRBoWvHkfi4hpVko2AwbaowNe4TuvcL5ARFeK3QE0up5vT sAw45sFJH9mxmg8sNykQcMXBly73pD6qH2zMqh4wkB+ZCrIXS0yFrcy8qA7NJN4PjEazHr5D9QDDh cy2N5lBPS6c7bAisMPPzsGnzCqGKfYxMq7q7xnXoPk6LAVo061yR+gGT2c5z8LMYS55tdV60xeFwP T5aYULBv5KIRpWa6UtL2/9C6N6oj4JeZOECnyQTtldB7rL86TMvdnd+OIR+PttO0qdA61HOsBMByi F+uC1UlSkKhKQeUupASA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xMkzv-0000000BZpN-1bTU; Fri, 30 Oct 2026 11:42:15 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xMkzs-0000000BZnr-1AT2 for linux-arm-kernel@lists.infradead.org; Fri, 30 Oct 2026 11:42:13 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 203521596; Fri, 30 Oct 2026 04:42:07 -0700 (PDT) Received: from LeoBrasDK.cambridge.arm.com (LeoBrasDK.cambridge.arm.com [10.2.212.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B86A03F7B4; Fri, 30 Oct 2026 04:42:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1793360530; bh=TryfSyMJmpjHJWemiNgo4MBnrsZct6ejB9ZK29wCuRI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XIVYestpCiqkWkpRrm7MMoeveYoA5FIQIuL/wKTNRlmW9R/fz0++XawOSAjqlO8Xy 6Oe7eykXf0SSQhKGDWSu4I/x7OTqVZ4S1lauXoLjNrGaFP13bMuZg8DoxKgM6Lw1gH Zhlv37cZ4yULbIomkP4C4YA8e8Zu7yMJb2FV7GWw= From: Leonardo Bras To: Wei-Lin Chang Cc: Leonardo Bras , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, Marc Zyngier , Oliver Upton , Fuad Tabba , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Mark Rutland , Gavin Shan , stable@vger.kernel.org Subject: Re: [PATCH v2 1/2] KVM: arm64: Fix dirty logging detection in ring-only mode Date: Fri, 30 Oct 2026 11:42:03 +0000 Message-ID: X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261029175238.3214788-2-weilin.chang@arm.com> References: <20261029175238.3214788-1-weilin.chang@arm.com> <20261029175238.3214788-2-weilin.chang@arm.com> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261030_044212_447676_EEFEE2F4 X-CRM114-Status: GOOD ( 19.45 ) X-Spam-Score: -4.4 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Thu, Oct 29, 2026 at 05:52:37PM +0000, Wei-Lin Chang wrote: > When checking whether a memslot has dirty logging enabled, the > KVM_MEM_LOG_DIRTY_PAGES flag is the source of truth. Previously in > memslot_is_logging() we were testing the dirty bitmap only and did not > consider dirty ring. > > With the ring and no bitmap, a logged memslot can still get block > mappings, so guest writes to most of a block are never logged and a > migration can copy stale memory. > > Fix this by using kvm_slot_dirty_track_enabled() instead which checks > KVM_MEM_LOG_DIRTY_PAGES, within memslot_is_logging(). > > Fixes: 9cb1096f8590 ("KVM: arm64: Enable ring-based dirty memory tracking") > Reviewed-by: Fuad Tabba > Tested-by: Fuad Tabba > Signed-off-by: Wei-Lin Chang > Cc: stable@vger.kernel.org > --- > arch/arm64/kvm/mmu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > index 705f6d84770e..c7df646af79f 100644 > --- a/arch/arm64/kvm/mmu.c > +++ b/arch/arm64/kvm/mmu.c > @@ -176,7 +176,7 @@ static int kvm_mmu_split_huge_pages(struct kvm *kvm, phys_addr_t addr, > > static bool memslot_is_logging(struct kvm_memory_slot *memslot) > { > - return memslot->dirty_bitmap && !(memslot->flags & KVM_MEM_READONLY); > + return kvm_slot_dirty_track_enabled(memslot) && !(memslot->flags & KVM_MEM_READONLY); > } > > static int pkvm_flush_remote_tlbs(struct kvm *kvm) > -- > 2.43.0 > Reviewed-by: Leonardo Bras Awesome, thanks for taking the suggestion! Leo