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 X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25E9AC433E0 for ; Wed, 5 Aug 2020 09:09:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE95E22CA1 for ; Wed, 5 Aug 2020 09:09:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=cloud.ionos.com header.i=@cloud.ionos.com header.b="H7x2XxOo" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727892AbgHEJJ2 (ORCPT ); Wed, 5 Aug 2020 05:09:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60186 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727787AbgHEJJS (ORCPT ); Wed, 5 Aug 2020 05:09:18 -0400 Received: from mail-wr1-x444.google.com (mail-wr1-x444.google.com [IPv6:2a00:1450:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 30F79C061756 for ; Wed, 5 Aug 2020 02:09:18 -0700 (PDT) Received: by mail-wr1-x444.google.com with SMTP id l2so29398415wrc.7 for ; Wed, 05 Aug 2020 02:09:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloud.ionos.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=+gIuoz/WMxbhVg8svooySeNXqd1nOMBCzPaYnalniCA=; b=H7x2XxOoNBWlRR/QNIt3KHaCYy0/Sez/plbm3JbhtBwN6esqx1sKDG9fpMkgUESZy8 dKrGlkX/UE85ohBEP4sI4R0EA0iHzlJ6HbyKLkEfjTW36/p6b/28L1pZFcrBQdD/6KlZ 1Y6XmZvLxrjlSiKASQQlICPQ/IiEe2xMNAcYuMTs8ztcd+qC95YucOrq+yYS11NHz3zl FwQGpeU5dMZayyJLRMweBInIWbe3XSV9EppWxyiQZ5JITSrRn4vnW2ckBnQor8ZNAhNL dQlTLAC3hJgSyzKBIvXVdIqDdPBBYDoFK25fG8LKtGpEQ+29S0gIpC4DSYWLf3AyxU2k TAug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=+gIuoz/WMxbhVg8svooySeNXqd1nOMBCzPaYnalniCA=; b=m6oWEBWK1IXMSJ9pqjxQ7NZysculsPmjHejCTv9/dlUnqn+lRdqETxxoGDNpvc5mIw fEdvgDiyztlZ28UIxhw94v0kye1vUqjlK7LFptCQRnBQooGnJKQ8kPzGLE57/dF5QjTD eJ6RRdLubeJSzsu2dfOB7556K/DiT1J0aRtQ0eEvv8fmZcztsTNO9HpwGoiBb5/jGLtU A0COgIPgqirQ7/YSaOi8ukvvp0Yy1MOvRbZWHAHH+mLb5qnz+19XdgcVzdsn0hfBVpvy OR9k4PUWL5FoYNZtfdWSFe3y5G3BsQxau20P0v1w5SzkqrCdFv3wy6dtgzgW6WZTxwGz b4JQ== X-Gm-Message-State: AOAM530hsPmchT99pBF8LxFFVTzRBiGsVnShDYNTI4Wt2Z1rbgBi1BMh gYkC0iwhJYnURmJvECpCVEw0TtFlzgsYq6K9u1a7 X-Google-Smtp-Source: ABdhPJxhjb0VZDK5fxfNwFfc3Dnra9SEbFypH7RYXTaQrPiVlwCOd/+IjuwLu2UQ2TxCKUguspu/L46XCaw0abgYK7o= X-Received: by 2002:adf:9526:: with SMTP id 35mr2033886wrs.326.1596618551488; Wed, 05 Aug 2020 02:09:11 -0700 (PDT) MIME-Version: 1.0 References: <20200623172321.GC6578@ziepe.ca> <20200804133759.377950-1-haris.iqbal@cloud.ionos.com> <20200805055712.GE4432@unreal> In-Reply-To: <20200805055712.GE4432@unreal> From: Danil Kipnis Date: Wed, 5 Aug 2020 11:09:00 +0200 Message-ID: Subject: Re: [PATCH v2] RDMA/rtrs-srv: Incorporate ib_register_client into rtrs server init To: Leon Romanovsky Cc: Md Haris Iqbal , Jinpu Wang , linux-rdma@vger.kernel.org, linux-block@vger.kernel.org, Doug Ledford , Jason Gunthorpe , "Chen, Rong A" Content-Type: text/plain; charset="UTF-8" Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi Leon, On Wed, Aug 5, 2020 at 7:57 AM Leon Romanovsky wrote: > > On Tue, Aug 04, 2020 at 07:07:58PM +0530, Md Haris Iqbal wrote: > > The rnbd_server module's communication manager (cm) initialization depends > > on the registration of the "network namespace subsystem" of the RDMA CM > > agent module. As such, when the kernel is configured to load the > > rnbd_server and the RDMA cma module during initialization; and if the > > rnbd_server module is initialized before RDMA cma module, a null ptr > > dereference occurs during the RDMA bind operation. > > > > Call trace below, > > > > [ 1.904782] Call Trace: > > [ 1.904782] ? xas_load+0xd/0x80 > > [ 1.904782] xa_load+0x47/0x80 > > [ 1.904782] cma_ps_find+0x44/0x70 > > [ 1.904782] rdma_bind_addr+0x782/0x8b0 > > [ 1.904782] ? get_random_bytes+0x35/0x40 > > [ 1.904782] rtrs_srv_cm_init+0x50/0x80 > > [ 1.904782] rtrs_srv_open+0x102/0x180 > > [ 1.904782] ? rnbd_client_init+0x6e/0x6e > > [ 1.904782] rnbd_srv_init_module+0x34/0x84 > > [ 1.904782] ? rnbd_client_init+0x6e/0x6e > > [ 1.904782] do_one_initcall+0x4a/0x200 > > [ 1.904782] kernel_init_freeable+0x1f1/0x26e > > [ 1.904782] ? rest_init+0xb0/0xb0 > > [ 1.904782] kernel_init+0xe/0x100 > > [ 1.904782] ret_from_fork+0x22/0x30 > > [ 1.904782] Modules linked in: > > [ 1.904782] CR2: 0000000000000015 > > [ 1.904782] ---[ end trace c42df88d6c7b0a48 ]--- > > > > All this happens cause the cm init is in the call chain of the module init, > > which is not a preferred practice. > > > > So remove the call to rdma_create_id() from the module init call chain. > > Instead register rtrs-srv as an ib client, which makes sure that the > > rdma_create_id() is called only when an ib device is added. > > > > Fixes: 9cb837480424 ("RDMA/rtrs: server: main functionality") > > Reported-by: kernel test robot > > Signed-off-by: Md Haris Iqbal > > --- > > drivers/infiniband/ulp/rtrs/rtrs-srv.c | 77 +++++++++++++++++++++++++- > > drivers/infiniband/ulp/rtrs/rtrs-srv.h | 7 +++ > > 2 files changed, 81 insertions(+), 3 deletions(-) > > Please don't send vX patches as reply-to in "git send-email" command. I thought vX + in-reply-to makes it clear that a new version of a patch is proposed in response to a mail reporting a problem in the first version. Why is that a bad idea? Thank you, Best, Danil. > > > > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > > index 0d9241f5d9e6..916f99464d09 100644 > > --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c > > @@ -16,6 +16,7 @@ > > #include "rtrs-srv.h" > > #include "rtrs-log.h" > > #include > > +#include > > > > MODULE_DESCRIPTION("RDMA Transport Server"); > > MODULE_LICENSE("GPL"); > > @@ -31,6 +32,7 @@ MODULE_LICENSE("GPL"); > > static struct rtrs_rdma_dev_pd dev_pd; > > static mempool_t *chunk_pool; > > struct class *rtrs_dev_class; > > +static struct rtrs_srv_ib_ctx ib_ctx; > > > > static int __read_mostly max_chunk_size = DEFAULT_MAX_CHUNK_SIZE; > > static int __read_mostly sess_queue_depth = DEFAULT_SESS_QUEUE_DEPTH; > > @@ -2033,6 +2035,62 @@ static void free_srv_ctx(struct rtrs_srv_ctx *ctx) > > kfree(ctx); > > } > > > > +static int rtrs_srv_add_one(struct ib_device *device) > > +{ > > + struct rtrs_srv_ctx *ctx; > > + int ret; > > + > > + /* > > + * Keep a track on the number of ib devices added > > + */ > > + ib_ctx.ib_dev_count++; > > + > > + if (!ib_ctx.rdma_init) { > > + /* > > + * Since our CM IDs are NOT bound to any ib device we will create them > > + * only once > > + */ > > + ctx = ib_ctx.srv_ctx; > > + ret = rtrs_srv_rdma_init(ctx, ib_ctx.port); > > + if (ret) { > > + /* > > + * We errored out here. > > + * According to the ib code, if we encounter an error here then the > > + * error code is ignored, and no more calls to our ops are made. > > + */ > > + pr_err("Failed to initialize RDMA connection"); > > + return ret; > > + } > > + ib_ctx.rdma_init = true; > > This rdma_init == false is equal to ib_ctx.ib_dev_count == 0 and the > logic can be simplified. > > if (ib_ctx.ib_dev_count) > return 0; > > ctx = ib_ctx.srv_ctx; > ret = rtrs_srv_rdma_init(ctx, ib_ctx.port); > if (ret) > return ret; > ib_ctx.ib_dev_count++; > return 0; > > > + } > > + > > + return 0; > > +} > > + > > +static void rtrs_srv_remove_one(struct ib_device *device, void *client_data) > > +{ > > + struct rtrs_srv_ctx *ctx; > > + > > + ib_ctx.ib_dev_count--; > > + > > + if (!ib_ctx.ib_dev_count && ib_ctx.rdma_init) { > > It is not kernel coding style. > if (ib_ctx.ib_dev_count) > return; > > ctx = ib_ctx.srv_ctx; > rdma_destroy_id(ctx->cm_id_ip); > rdma_destroy_id(ctx->cm_id_ib); > > Thanks > > > + /* > > + * Since our CM IDs are NOT bound to any ib device we will remove them > > + * only once, when the last device is removed > > + */ > > + ctx = ib_ctx.srv_ctx; > > + rdma_destroy_id(ctx->cm_id_ip); > > + rdma_destroy_id(ctx->cm_id_ib); > > + ib_ctx.rdma_init = false; > > + } > > +} > > + > > +static struct ib_client rtrs_srv_client = { > > + .name = "rtrs_server", > > + .add = rtrs_srv_add_one, > > + .remove = rtrs_srv_remove_one > > +}; > > + > > /** > > * rtrs_srv_open() - open RTRS server context > > * @ops: callback functions > > @@ -2051,12 +2109,26 @@ struct rtrs_srv_ctx *rtrs_srv_open(struct rtrs_srv_ops *ops, u16 port) > > if (!ctx) > > return ERR_PTR(-ENOMEM); > > > > - err = rtrs_srv_rdma_init(ctx, port); > > + ib_ctx = (struct rtrs_srv_ib_ctx) { > > + .srv_ctx = ctx, > > + .port = port, > > + }; > > + > > + err = ib_register_client(&rtrs_srv_client); > > if (err) { > > free_srv_ctx(ctx); > > return ERR_PTR(err); > > } > > > > + /* > > + * Since ib_register_client does not propagate the device add error > > + * we check if the RDMA connection init was successful or not > > + */ > > + if (!ib_ctx.rdma_init) { > > + free_srv_ctx(ctx); > > + return NULL; > > + } > > + > > return ctx; > > } > > EXPORT_SYMBOL(rtrs_srv_open); > > @@ -2090,8 +2162,7 @@ static void close_ctx(struct rtrs_srv_ctx *ctx) > > */ > > void rtrs_srv_close(struct rtrs_srv_ctx *ctx) > > { > > - rdma_destroy_id(ctx->cm_id_ip); > > - rdma_destroy_id(ctx->cm_id_ib); > > + ib_unregister_client(&rtrs_srv_client); > > close_ctx(ctx); > > free_srv_ctx(ctx); > > } > > diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.h b/drivers/infiniband/ulp/rtrs/rtrs-srv.h > > index dc95b0932f0d..6e9d9000cd8d 100644 > > --- a/drivers/infiniband/ulp/rtrs/rtrs-srv.h > > +++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.h > > @@ -118,6 +118,13 @@ struct rtrs_srv_ctx { > > struct list_head srv_list; > > }; > > > > +struct rtrs_srv_ib_ctx { > > + struct rtrs_srv_ctx *srv_ctx; > > + u16 port; > > + int ib_dev_count; > > + bool rdma_init; > > +}; > > + > > extern struct class *rtrs_dev_class; > > > > void close_sess(struct rtrs_srv_sess *sess); > > -- > > 2.25.1 > >