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 A29C236C9E3 for ; Sat, 28 Feb 2026 18:11:44 +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=1772302304; cv=none; b=CBH5aaSQWM93k9LbEDCWUxkXEQiA6ETF30HlVE8EfhEJyk/SXbIiwR1yp9FyqVgPd998iXsVYENPj1PmSQLNElPZiJsR0/oRB57gDYBUWertxZfC3gOFmd88Zef4tANunl9r8Co407ocDONSkVzGsDSK3iCBwG6ffe3jrSWDpxg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302304; c=relaxed/simple; bh=6OYWL4b9WvFaf1PM6WVHSd1BFYq6ywzlhYSxR1XvxN0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MDjzRmdA02azADokLRBXikfKT8qkkeLTf4TNg+e6FdmL/T9VEHhpdlstUPa/ACnLIOuxWkE9cnDuyCCQrTmqHqZv7cMCDoIeo1QG1rnhcoo0NLd79CDxek2eXdALLz0wRp/+e+0fa7YjaqwIRP+Wl2tGcROiInIdvLonu56IGFA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Fj9AwHgD; 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="Fj9AwHgD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1105DC19424; Sat, 28 Feb 2026 18:11:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302304; bh=6OYWL4b9WvFaf1PM6WVHSd1BFYq6ywzlhYSxR1XvxN0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Fj9AwHgDUU7F3zEjliRq4PH1X7jHJmn1YZmwgk+cLArm0FuUUjw6qvwViQ7mDOFhc 6dErEsm3kekEaLZQV1LiBzlr8TriRo8hvp7xESUG5lyrSnvXiURKvR0XGN5Q9UIaDP HMYM0T4RD7YkrHbfDMptg90HqdCAdic8/qWSMfMAmvKjEN2qBaeemCvvLZEd4fZj9D MW1fhB2H/Ga7uq50kjRckRkQoVmZyyqFGeAES/2VoZOreH2j80NcYEn4myf1yEFlw0 71OPqi3gsM7pJaBAPfPPsiQhJKEVL1nkhfRSNM5r6ZIHe5K8KwVMeRcNEbjOux4/29 3rg/OKPNws/6w== From: Sasha Levin To: patches@lists.linux.dev Cc: Teddy Astie , Juergen Gross , Sasha Levin Subject: [PATCH 6.1 019/232] xen/virtio: Don't use grant-dma-ops when running as Dom0 Date: Sat, 28 Feb 2026 13:07:52 -0500 Message-ID: <20260228181127.1592657-19-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181127.1592657-1-sashal@kernel.org> References: <20260228181127.1592657-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Teddy Astie [ Upstream commit dc8ea8714311e549ee93a2b0bdd5487d20bfadbf ] Dom0 inherit devices from the machine and is usually in PV mode. If we are running in a virtual that has virtio devices, these devices would be considered as using grants with Dom0 as backend, while being the said Dom0 itself, while we want to use these devices like regular PCI devices. Fix this by preventing grant-dma-ops from being used when running as Dom0 (initial domain). We still keep the device-tree logic as-is. Signed-off-by: Teddy Astie Fixes: 61367688f1fb0 ("xen/virtio: enable grant based virtio on x86") Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <6698564dd2270a9f7377b78ebfb20cb425cabbe8.1767720955.git.teddy.astie@vates.tech> Signed-off-by: Sasha Levin --- drivers/xen/grant-dma-ops.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c index 9784a77fa3c99..46cc47bd1dd0f 100644 --- a/drivers/xen/grant-dma-ops.c +++ b/drivers/xen/grant-dma-ops.c @@ -360,7 +360,8 @@ static int xen_grant_init_backend_domid(struct device *dev, if (np) { ret = xen_dt_grant_init_backend_domid(dev, np, backend_domid); of_node_put(np); - } else if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain()) { + } else if (!xen_initial_domain() && + (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain())) { dev_info(dev, "Using dom0 as backend\n"); *backend_domid = 0; ret = 0; -- 2.51.0