From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8784121D5AE for ; Wed, 26 Feb 2025 18:58:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740596335; cv=none; b=pEgDguZu4N6UeMaB3xvjb4CKMe6JU6VAP42K2w1otac3n3+UTjIdT6dpSkPh2Kh7bh71t5zNgfjvYoSngFXpIuKwa3pOLA5PHceKyfrEYuwVbyX8d5VcN8prKa4FujXzsiSvJzTen0L6a5+zXOMwsZKyIFK+SyvVUMLAiTE1ce8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740596335; c=relaxed/simple; bh=qYUiwdCA5X+JoCTrBOTaytW2dcp+reoA3o1dWdtDpzE=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=JAGvJmzqlmor6GEQ1GOlXUtoZiNA4Y53MZZ1DgtHlnhMFdXUCJCLVeaKmyyryDTklXW+6wt0HboJfy9M9dDk6OaOSHS4oAUH0TtlaaD9iWXjhqqEQ8mZ9UDOLEIlsoPs1ouuhVgiKqRUFt/kCy98JKkVoLyPDj13ZE1iOzGwqw0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=q7XwCNnW; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="q7XwCNnW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 11B77C4CED6; Wed, 26 Feb 2025 18:58:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740596334; bh=qYUiwdCA5X+JoCTrBOTaytW2dcp+reoA3o1dWdtDpzE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=q7XwCNnW4T8dsNywxyJvzoZhrChJCwFB4dpy13Z7xFA1FG4CWz3y2wcrre7tvjHuW WkHG0EuCUuD+JwizfBfVOUXtMTpLxIIYXKV4YxWmE4gVkZ7U8mxDBeG98gIhXpTuvG zTH1ewdBZvVit+ZgxKVOp6Orj7uwV1lTgcvvhUPiHfGjGhsj9pRq9L3ZA03UMSJ60W smH6fvZYnFOjnIDv5yBMDusunBc3Pa6bynkM+s4s7Puc19hGI6y+S7fd4qIzja4TY2 a9FUX0/jSF5CKSG+pE3FJM+roPW7EyrWpKQpQ0vzq6qMyIzi0lr/YzweDxZncDegiP cat8LHudiMLog== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1tnMcN-008Oe4-Sa; Wed, 26 Feb 2025 18:58:51 +0000 Date: Wed, 26 Feb 2025 18:58:51 +0000 Message-ID: <864j0gr0r8.wl-maz@kernel.org> From: Marc Zyngier To: Oliver Upton Cc: kvmarm@lists.linux.dev, Joey Gouly , Suzuki K Poulose Subject: Re: [PATCH 0/4] KVM: arm64: Fixes/clarification for GICv4 vLPI injection In-Reply-To: <20250226183124.82094-1-oliver.upton@linux.dev> References: <20250226183124.82094-1-oliver.upton@linux.dev> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/29.4 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: oliver.upton@linux.dev, kvmarm@lists.linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Wed, 26 Feb 2025 18:31:20 +0000, Oliver Upton wrote: > > Small batch of fixes for vLPI injection issues that can happen when > userspace is being mean: > > - MSI interrupt sources could be mapped to non-MSI GSI routing entries. > KVM doesn't account for the routing type and blindly attempts to map > a vLPI. > > - KVM_IRQFD mappings could be installed before the ITS has been > restored, leading to kvm_vgic_v4_set_forwarding() failing due to the > missing guest translation > > Prevent userspace from triggering a WARN() because of these issues and > gracefully fall back to software vLPI routing/injection should irqbypass > fail. > > I've thrown in some documentation on the restore ordering necessary to get > GICv4 vLPI injection working correctly as well. > > Marc, I'm planning to take these for 6.15. Go for it. Acked-by: Marc Zyngier M. -- Without deviation from the norm, progress is not possible.