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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 50A45C3064D for ; Tue, 2 Jul 2024 10:24:54 +0000 (UTC) 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:MIME-Version: Content-Transfer-Encoding:Content-Type:References:In-Reply-To:Date:Cc:To:From :Subject:Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=PGN/Z4nHpXQCi6h5qSdSGZE78U7FokNZlM0EE7rRTNo=; b=0fd9VuiyLuT9IkWV4B/ixOGDTr YcdW2Cd8mDHLNXx91ZS7DGDQfsjIfkBQYH4bNjJ3BJmgOb4InqzrNNXHWGd+eIPmh4mCkNTQHAGil 2i9B+mU73I1BTk2vlX5VVN8cYqTpO5XBZKt3vniblsUjI1jzVXbq73a4S6vFz8cZ+GPvZzbey92ko IPbUBTzWElw/YKnVPmJ8pevqV5dGH5vXidmzW37VgTx0JXXfs5iUip/2ccSJkEk15cbKOIeRDwCyY JB6cGWqi6D7GbwnFKUHDN2ao3bKEjaLE5YfAmuU04xNVP/2Hmwo0WPfwTiPdEuDNp6V1cQjQsvKc4 J/QxYDxw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sOagv-00000006LDd-2TU3; Tue, 02 Jul 2024 10:24:53 +0000 Received: from s3.sipsolutions.net ([2a01:4f8:242:246e::2] helo=sipsolutions.net) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sOagt-00000006LDE-2yau for linux-um@lists.infradead.org; Tue, 02 Jul 2024 10:24:52 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=PGN/Z4nHpXQCi6h5qSdSGZE78U7FokNZlM0EE7rRTNo=; t=1719915891; x=1721125491; b=wgGLJhKJodk4hRjoV1jI0xG+IZtfYMTWb+iuACgKZhAM8Z5 OEPjgvvPqUdzCeLWJTMmM9nd/wZfPlxfK3AXcegwUoyg8h4nNlZPaprddzVp2O7VnA5i85tWRFH9M dHDTHQ7VJrbfS/H9cSso9jiIV+WfTJSUzHz5Glzr2cKePVt4x1H2Zlr+wlOQhqJ9IUHhA647oiy62 iWw+cJDnBzv+Qv49JfhRq0EFuRUpPbAquFFifp9eUiKwtfECdktmfHc9bewVKB1YhKmH87NayC5Ta gORlNQyoKhZNfhEAuOx7Ma+6SmOZqwHaXPaLxhV8UqwBMVbwDFsV/H56DD5bAqJg==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.97) (envelope-from ) id 1sOagq-00000005CqG-29iD; Tue, 02 Jul 2024 12:24:48 +0200 Message-ID: Subject: Re: [PATCH v10] um: Enable preemption in UML From: Johannes Berg To: linux-um@lists.infradead.org Cc: Anton Ivanov Date: Tue, 02 Jul 2024 12:24:47 +0200 In-Reply-To: <20240702102549.d2fcea450854.I12f5a53d80ec1e425e66ef272b1e95cb523b608e@changeid> References: <20240702102549.d2fcea450854.I12f5a53d80ec1e425e66ef272b1e95cb523b608e@changeid> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.52.2 (3.52.2-1.fc40) MIME-Version: 1.0 X-malware-bazaar: not-scanned X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240702_032451_768333_9AFAA54E X-CRM114-Status: UNSURE ( 6.94 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org On Tue, 2024-07-02 at 10:25 +0200, Johannes Berg wrote: > From: Anton Ivanov >=20 > Since userspace state is saved in the MM process, kernel using > FPU still doesn't really need to do anything, so this really > is as simple as enabling preemption. The irq critical section > in sigio_handler() needs preempt_disable()/preempt_enable(). For the record, my main interest in this is to unlock debugging for RCU lists, sleep, etc. johannes