From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794045896; b=Mtjc4EwGDbFttwDt2PrNAfgWyR7yauPp6Z4tPhmeXcrcOoPL9uJNJjkNea8uoaywyGKm XZqCPYscOVCY+1e7dvi4UoILCYMddFVLp5pQpXJl0RLIIPXrBI/PbWkuT64wsBXCjS/nB ioB/AZPxFiscwQFtWJYplavKXtpoD/++FAht0PhyLBQ7UrPk7VtWc9P/9u+x+ve10vEWQ TwnYr1ZiBhrQOcRMZOc3TRDEYic3mW2aVGzWDQ06OkTBSDY+LtojvHxw76ux5hPWor+2+ izEWaDnck2i+LCq/j0F4UJ9cc/UopHoMKCSA6yZ+0pFgZXYVbMHZUPFk3iWDEK1unHQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794045896; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=Mb4KdWH/f83YVwEgUrk/PijBYFwimeMrr6ICHV7NJRs=; b=FApRie31qmDTnM31kM8jvzbbYooMFZrpCCGr53jWL4I/cFOmRcT52pLYk8L9v6VoVq4q 218xS30RhiOViT9WBZcd1h21LrupM2iL8tVXK3oulCqyCITU+dFyTg4AGtvk3FFtvANvp 1wEgID1kSdAEq6RwzmHWipPnN2epGEPGveAniZ6WLmtpbhIm6wLqSPR0Qw8bydd8v+qgL YlsW0fAiU7rTAfkBYnqAEqqgjIWaK8joX2pM7bPcHPoaqN60You98SX7+J9R/SKwOOHbY pJCjtLZUmkWRV/8Pzuy07qoqKfTB+Jy1KQijbtCTUEkDSPdpj1Vl4CND4UDUoAI5/nw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QUtS67wt; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D2DF1606A326 for ; Sat, 7 Nov 2026 10:04:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QUtS67wt Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35B871F0089F; Sat, 7 Nov 2026 10:04:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794045895; bh=Mb4KdWH/f83YVwEgUrk/PijBYFwimeMrr6ICHV7NJRs=; h=From:To:Cc:Subject:Date; b=QUtS67wtMUFkBUuQo9D/6inVtnCVvbLgAYdqrUihujtHIKPsy5RpD2Zz/dpoB2u+4 Jc9T651MhJbe9e7E7if9q/gw5AfA51hjNMqS8GkJ4D9CsIG3peyMdbTkVWSiDoKBtx QzB8Vh0WfXECXedlAnye+UWRJhFJ/8SUTXsMP05oa4jLfVwbDguKWY0f3Jc8akD4lK vtt2eEzXZFOCcMIMxOEKtMvgXsib6GzA9gMwHjsbJf9vV1yQP7o25Sp+RjW9jx8luG 9rTmTjgf4iJOQdCVe8bXYSh7nTODNQZVyisLd4Obp5F527CjIzn4glvcvE2GQJA8pr cbfSrgg9pPCbw== From: Sasha Levin To: maz@kernel.org, oupton@kernel.org, fuad.tabba@linux.dev Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] KVM: arm64: vgic: Stop the target vcpu when disabling LPIs" failed to apply to 7.3-stable tree Date: Sat, 7 Nov 2026 05:04:54 -0500 Message-ID: <20261107050454-failed-7.3-a1b4bd2c2c26@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 7.3-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-7.3.y git checkout FETCH_HEAD git cherry-pick -x a1b4bd2c2c262b8094c86afb99364d16ac08cb66 # git commit -s git send-email --to '' --in-reply-to '20261107050454-failed-7.3-a1b4bd2c2c26@kernel.org' --subject-prefix 'PATCH 7.3.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From a1b4bd2c2c262b8094c86afb99364d16ac08cb66 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 15 Oct 2026 11:05:38 +0100 Subject: [PATCH] KVM: arm64: vgic: Stop the target vcpu when disabling LPIs Disabling LPIs is pretty nasty, as it directly messes with the AP list of the affected CPU, which could be running... This has the potential to lead to really bad behaviours, and we should not be doing that. Take example on the way the Active state is handled and simply pause the the vcpu so that we are sure it is in a quiescent state, and the state be safely manipulated. Nobody has any expectation of performance for this anyway. Fixes: 96085b949672d ("KVM: arm/arm64: vgic-v3: Retire pending interrupts on disabling LPIs") Co-developed-by: Oliver Upton Signed-off-by: Oliver Upton Cc: stable@vger.kernel.org Reviewed-by: Fuad Tabba Tested-by: Fuad Tabba Link: https://patch.msgid.link/20261015100539.1011760-7-maz@kernel.org Signed-off-by: Marc Zyngier --- arch/arm64/kvm/vgic/vgic-mmio-v3.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/arm64/kvm/vgic/vgic-mmio-v3.c b/arch/arm64/kvm/vgic/vgic-mmio-v3.c index 5913a20d83019..f5bd29fbe3a90 100644 --- a/arch/arm64/kvm/vgic/vgic-mmio-v3.c +++ b/arch/arm64/kvm/vgic/vgic-mmio-v3.c @@ -303,9 +303,19 @@ static void vgic_mmio_write_v3r_ctlr(struct kvm_vcpu *vcpu, if (ctlr != GICR_CTLR_ENABLE_LPIS) return; + /* + * Yes, disabling LPIs is painful, since it can be done from + * a *remote* vcpu! So let's not take any chance, and make + * sure that the target vCPU has written their LRs back to the + * irq structures, and release any reference they would have. + * + * If it hurts, don't do it. + */ + kvm_pause_vcpu(vcpu); vgic_flush_pending_lpis(vcpu); vgic_its_invalidate_all_caches(vcpu->kvm); atomic_set_release(&vgic_cpu->ctlr, 0); + kvm_resume_vcpu(vcpu); } else { ctlr = atomic_cmpxchg_acquire(&vgic_cpu->ctlr, 0, GICR_CTLR_ENABLE_LPIS); -- 2.53.0