From patchwork Fri Jan 20 16:21:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 13110155 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5DF2C25B4E for ; Fri, 20 Jan 2023 16:22:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229834AbjATQWU (ORCPT ); Fri, 20 Jan 2023 11:22:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229936AbjATQWT (ORCPT ); Fri, 20 Jan 2023 11:22:19 -0500 Received: from mail-ej1-x631.google.com (mail-ej1-x631.google.com [IPv6:2a00:1450:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F3F45648C for ; Fri, 20 Jan 2023 08:22:14 -0800 (PST) Received: by mail-ej1-x631.google.com with SMTP id bk15so15202905ejb.9 for ; Fri, 20 Jan 2023 08:22:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=lL/MFQt8b8dhap63osJLhrmA3bFPT55Fdb32RgCKHtM=; b=XpnNg3W57ntM/qtWoQLEGLuGEEe8oycuXUmfYOlzQkukfykPLHLF/S+J0b28/+jH7+ rbNbZU/pyY4VyoNxrSeyvQGt6nm11eCYKcR2km2Xj9Zl4VAWugn8zleeSZBsbgt5swxr Mqz8Y4ApG2XaZjbJjKOHrxrfnzInj+AB0St1asGi8LqV+E+sO1CQjODrZS8l9CB+VmP3 enAtzYtVbtCiQ/nPIPoJB+KJi6rm8DDczQXw57wk0LD1BIcIk8D3LcPRF9FuVgAv/los ZPugvTrTSj7sFxJyItp+mPf21l/V+Brst/xa0DydhuBWv/H9FiQ+94IWgKJUU241wBOO 3+IA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lL/MFQt8b8dhap63osJLhrmA3bFPT55Fdb32RgCKHtM=; b=AA6hYSGzEyQUC4ojkfxGf3k9rasZov8SwFqnMli8H9cZWGEr9AoHr4+trdxx/C0mnB RBYk593G0Vwhw1OBOElUPU8l1uVzXgTjBCRbNupsMwlNeh1EIrDTdc2IBsAmZx/nMGMy kINCgq4umqBQpDDac2sP6ByGK54F6Ts3JqsQXqdWsskAB9qyG7553/03ebGqMahG2RaJ Y5AHXvou5B9Xaizf/d00P7fSXuf18Ko36iwlgFEc0PXnbYqlv8yQh13gtTvXsLhhmt0m XtKy2S+5m6GYNYJRJKA/xda6A24MKU6oeKsrXnpl0hZ7zy6w+EVCRge8QlApG7w7WYgW UiCQ== X-Gm-Message-State: AFqh2kpCFBK3UkSskLz699kGVtaZ0z6Kq8fVjqWS3AfOpOpp9d8mnMoy OP0iLspkrIRnHmKQQR9snJQW9lp5XpI= X-Google-Smtp-Source: AMrXdXv87X56bSi2Zj3DJw9LKtfjL8u2i44TFQjDuwQcfUA7A0uJSdETQZrNPFKe8tJH7Gyw2JhLKQ== X-Received: by 2002:a17:907:d406:b0:846:8c9a:68a0 with SMTP id vi6-20020a170907d40600b008468c9a68a0mr18339938ejc.30.1674231732818; Fri, 20 Jan 2023 08:22:12 -0800 (PST) Received: from 127.com ([2620:10d:c092:600::2:4670]) by smtp.gmail.com with ESMTPSA id s12-20020a1709060c0c00b0086621d9d9b0sm11406040ejf.81.2023.01.20.08.22.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Jan 2023 08:22:12 -0800 (PST) From: Pavel Begunkov To: io-uring@vger.kernel.org Cc: Jens Axboe , asml.silence@gmail.com Subject: [PATCH for-6.2 2/3] io_uring/msg_ring: fix remote queue to disabled ring Date: Fri, 20 Jan 2023 16:21:00 +0000 Message-Id: <845f25277fd30f80ecff4a1352bb10739f300b28.1674231554.git.asml.silence@gmail.com> X-Mailer: git-send-email 2.38.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org IORING_SETUP_R_DISABLED rings don't have the submitter task set, so it's not always safe to use ->submitter_task and we have to check if it has already been set. Fixes: 6d043ee1164ca ("io_uring: do msg_ring in target task via tw") Signed-off-by: Pavel Begunkov --- io_uring/io_uring.c | 4 ++-- io_uring/msg_ring.c | 4 ++++ 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 2ac1cd8d23ea..0a4efada9b3c 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3674,7 +3674,7 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, if (ctx->flags & IORING_SETUP_SINGLE_ISSUER && !(ctx->flags & IORING_SETUP_R_DISABLED)) - ctx->submitter_task = get_task_struct(current); + WRITE_ONCE(ctx->submitter_task, get_task_struct(current)); file = io_uring_get_file(ctx); if (IS_ERR(file)) { @@ -3868,7 +3868,7 @@ static int io_register_enable_rings(struct io_ring_ctx *ctx) return -EBADFD; if (ctx->flags & IORING_SETUP_SINGLE_ISSUER && !ctx->submitter_task) - ctx->submitter_task = get_task_struct(current); + WRITE_ONCE(ctx->submitter_task, get_task_struct(current)); if (ctx->restrictions.registered) ctx->restricted = 1; diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c index bb868447dcdf..c68cd3898035 100644 --- a/io_uring/msg_ring.c +++ b/io_uring/msg_ring.c @@ -69,6 +69,10 @@ static int io_msg_exec_remote(struct io_kiocb *req, task_work_func_t func) { struct io_ring_ctx *ctx = req->file->private_data; struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg); + struct task_struct *task = READ_ONCE(ctx->submitter_task); + + if (unlikely(!task)) + return -EOWNERDEAD; init_task_work(&msg->tw, func); if (task_work_add(ctx->submitter_task, &msg->tw, TWA_SIGNAL))