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=-12.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 51BABC433E0 for ; Tue, 21 Jul 2020 20:58:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2BE9620729 for ; Tue, 21 Jul 2020 20:58:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="mHdARhUT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730488AbgGUU6c (ORCPT ); Tue, 21 Jul 2020 16:58:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728944AbgGUU6b (ORCPT ); Tue, 21 Jul 2020 16:58:31 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 201A4C0619DC for ; Tue, 21 Jul 2020 13:58:31 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id u185so44831pfu.1 for ; Tue, 21 Jul 2020 13:58:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=X52qI9IuX8ehsLxlnySnmok7XL1KtNCuLE+99FuZBeI=; b=mHdARhUTuiPaFxjw12aZ6Wa9+kLghKQ0fq8ZJpwVAledPTAoh2U3VGDsfsyr4CtWiS NXuH7AFqDcCmAepHllRQ4Wq6geSc5R3h6YB/TWlMfokX4+eEHRFZKFDVxGqrMiu2MRku 91nIm/w9OxN3qHJykIwzJ//I2SrZPpLlqSXMiGkKwGrq7deQxUUahBBRIdBCDYalvXeO RXkwNN69nSl3vRbDjY12ItnzNxSn54y5LrsKUYN1XwkelXZrn2ofOPGVf1/ffcUuaa7h a83DRCCTf2xgI5VIfkzGeDM08SV43UCY0a72ArB/oCDawwpiJKf3+5B7lUPaBFF2NcE8 0C2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=X52qI9IuX8ehsLxlnySnmok7XL1KtNCuLE+99FuZBeI=; b=VEvi5sbqFg2oXHtbfCu+0CSbiivslW5j0fWRN/OM0S/hE5HRRa2pulOIGqD6JyUV89 giddP4frolO7pSaeuZnDbLFQmsC/S2IBdh5jDs9SnOsiVvjnw6IRM+FXWgIbBE7aYJ8R fUn+uWYSLw694GNtps4ItG1ilJ16SdIDXwWNpLiCT02UHCj20njnrpazDD1sAShczHGR rV6xt5Ai+YTHqQr3soLXw8M8/2UqLtqoEFs+mGbW+vD2O2iIT8SchOTktQPNmH/gnaMJ IItFi9x261JBRD7esv6gZ6AYDhl8U7l2uSw1cL7lR/lxE9hB7pRn2GTlNZPQPbSinhH1 /j4Q== X-Gm-Message-State: AOAM532lSvHIzpaSMvjXasGktjWB/IcRd87CvTn0PRejJmh5NfZSs6ym LbKc4nlR4jcF3Q563smq++D/4Q== X-Google-Smtp-Source: ABdhPJzipImp2FJDXR65FI4cQBfU1/ZWv6fskJvunQo3KeiwYFfoMSTrdro0BQYaNbHlwWG5ksZP1g== X-Received: by 2002:a63:c049:: with SMTP id z9mr19741380pgi.353.1595365110347; Tue, 21 Jul 2020 13:58:30 -0700 (PDT) Received: from builder.lan (104-188-17-28.lightspeed.sndgca.sbcglobal.net. [104.188.17.28]) by smtp.gmail.com with ESMTPSA id z25sm21277934pfg.140.2020.07.21.13.58.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Jul 2020 13:58:29 -0700 (PDT) Date: Tue, 21 Jul 2020 13:56:35 -0700 From: Bjorn Andersson To: Siddharth Gupta Cc: Mathieu Poirier , agross@kernel.org, ohad@wizery.com, corbet@lwn.net, linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, tsoni@codeaurora.org, psodagud@codeaurora.org, rishabhb@codeaurora.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v4 1/2] remoteproc: Add remoteproc character device interface Message-ID: <20200721205635.GM2922385@builder.lan> References: <1594148870-27276-1-git-send-email-sidgup@codeaurora.org> <1594148870-27276-2-git-send-email-sidgup@codeaurora.org> <20200715201839.GA3204081@xps15> <20200715215149.GA3267350@xps15> <81d7514c-727e-b4dc-e4ac-74a25966ccaf@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <81d7514c-727e-b4dc-e4ac-74a25966ccaf@codeaurora.org> Sender: linux-remoteproc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-remoteproc@vger.kernel.org On Tue 21 Jul 12:16 PDT 2020, Siddharth Gupta wrote: > On 7/15/2020 2:51 PM, Mathieu Poirier wrote: > > On Wed, Jul 15, 2020 at 02:18:39PM -0600, Mathieu Poirier wrote: > > > On Tue, Jul 07, 2020 at 12:07:49PM -0700, Siddharth Gupta wrote: [..] > > > > diff --git a/drivers/remoteproc/remoteproc_cdev.c b/drivers/remoteproc/remoteproc_cdev.c [..] > > > > +int rproc_char_device_add(struct rproc *rproc) > > > > +{ > > > > + int ret; > > > > + dev_t cdevt; > > > > + > > > > + cdev_init(&rproc->char_dev, &rproc_fops); > > > > + rproc->char_dev.owner = THIS_MODULE; > > > > + > > > > + cdevt = MKDEV(rproc_major, rproc->index); > > > > + ret = cdev_add(&rproc->char_dev, cdevt, 1); > > Trying this patchset on my side gave me the following splat[1]. After finding > > the root case I can't understand how you haven't see it on your side when you > > tested the feature. > > > > [1]. https://pastebin.com/aYTUUCdQ Mathieu, I've looked at this back and forth. Afaict this implies that rproc_major is still 0. Could it be that either alloc_chrdev_region() failed or somehow has yet to be called when you hit this point? > Hey Mathieu, > > We aren't able to reproduce the error that you are seeing, the splat is > coming > from the check for whiteout device[1] - which shouldn't happen because of > the > find_dynamic_major call[2], right? > > We are successfully seeing all our character device files and able to > successfully boot remoteprocs. From what I read and understood about > whiteout > devices they will be hidden in the fs. > > Could you provide more details about your configuration and testing? > > [1]: https://github.com/torvalds/linux/blob/master/fs/char_dev.c#L486 > > [2]: https://github.com/torvalds/linux/blob/master/fs/char_dev.c#L123 > > > > > > + if (ret < 0) > > > > + goto out; > > > > + > > > > + rproc->dev.devt = cdevt; > > > > +out: > > > > + return ret; > > > > +} > > > > + > > > > +void rproc_char_device_remove(struct rproc *rproc) > > > > +{ > > > > + __unregister_chrdev(rproc_major, rproc->index, 1, "remoteproc"); > > > > +} > > > > + > > > > +void __init rproc_init_cdev(void) > > > > +{ > > > > + int ret; > > > > + > > > > + ret = alloc_chrdev_region(&rproc_major, 0, NUM_RPROC_DEVICES, "remoteproc"); > > > > + if (ret < 0) > > > > + pr_err("Failed to alloc rproc_cdev region, err %d\n", ret); > > > > +} > > > > + > > > > +void __exit rproc_exit_cdev(void) > > > > +{ > > > > + unregister_chrdev_region(MKDEV(rproc_major, 0), NUM_RPROC_DEVICES); > > > Please go back to the comment I made on this during my last review and respin. > > After digging in the code while debugging the above problem, I don't see how > > unregistering the chrdev region the way it is done here would have worked. > Since this is compiled statically and not built as a module, we will never > exercise the code path, so I will remove it in the next patchset. > You're right Siddharth, since we changed CONFIG_REMOTEPROC to bool it's no longer possible to hit remoteproc_exit(), so you can omit this function entirely. (And we should clean up the rest of that as well) [..] > > > > diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h [..] > > > > @@ -488,6 +489,8 @@ struct rproc_dump_segment { > > > > * @auto_boot: flag to indicate if remote processor should be auto-started > > > > * @dump_segments: list of segments in the firmware > > > > * @nb_vdev: number of vdev currently handled by rproc > > > > + * @char_dev: character device of the rproc > > > > + * @cdev_put_on_release: flag to indicate if remoteproc should be shutdown on @char_dev release > > > > */ > > > > struct rproc { > > > > struct list_head node; > > > > @@ -523,6 +526,8 @@ struct rproc { > > > > int nb_vdev; > > > > u8 elf_class; > > > > u16 elf_machine; > > > > + struct cdev char_dev; As stated privately, I assumed based on this name that this is a struct device related to that character device. So please rename this cdev to save me from doing this mistake again. Thanks, Bjorn 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=-12.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 87D7AC433E1 for ; Tue, 21 Jul 2020 21:00:04 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4E17C2068F for ; Tue, 21 Jul 2020 21:00:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="wTSD19Mi"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="mHdARhUT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4E17C2068F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Jme1iSq8BZXo61OeIg7ry/h+H8wVzH18cnfFPTAS+/4=; b=wTSD19MiE1o3PxX9F7Tx1uoLN hkVTtlAK8G1B79KfLYDrz019WvYC1volclsWhfkDkA1rnB+0XaXourpi/HxKXkRVAEFV8ns2Lwd0G bfwJQi9sg4Fw+BXLCNYYcQv89FKDhjN1lXrD0pgrlcrDPi97xoR10eNVBq3N01u9KfMVdidqQhSTA fL+H4t2VZauMaz5kLBYvI5ya4cRwmMmAifL9EfjCU3m9bYztWNi8QNPFVLfNxUcMrvvvie08K3YZP 4K3GrlkFrz9rFcs05xb8xgTdPcttpp1ADMtOD8YnYuqfe2UOa4o5p7HbZGcAgXGJQrppg4AgEljE2 ZuuHUVa3Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jxzLR-0000IW-Gq; Tue, 21 Jul 2020 20:58:37 +0000 Received: from mail-pf1-x444.google.com ([2607:f8b0:4864:20::444]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jxzLN-0000HJ-FY for linux-arm-kernel@lists.infradead.org; Tue, 21 Jul 2020 20:58:35 +0000 Received: by mail-pf1-x444.google.com with SMTP id z3so18653pfn.12 for ; Tue, 21 Jul 2020 13:58:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=X52qI9IuX8ehsLxlnySnmok7XL1KtNCuLE+99FuZBeI=; b=mHdARhUTuiPaFxjw12aZ6Wa9+kLghKQ0fq8ZJpwVAledPTAoh2U3VGDsfsyr4CtWiS NXuH7AFqDcCmAepHllRQ4Wq6geSc5R3h6YB/TWlMfokX4+eEHRFZKFDVxGqrMiu2MRku 91nIm/w9OxN3qHJykIwzJ//I2SrZPpLlqSXMiGkKwGrq7deQxUUahBBRIdBCDYalvXeO RXkwNN69nSl3vRbDjY12ItnzNxSn54y5LrsKUYN1XwkelXZrn2ofOPGVf1/ffcUuaa7h a83DRCCTf2xgI5VIfkzGeDM08SV43UCY0a72ArB/oCDawwpiJKf3+5B7lUPaBFF2NcE8 0C2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=X52qI9IuX8ehsLxlnySnmok7XL1KtNCuLE+99FuZBeI=; b=kM4EnYvWpQ+7l51rMz6WjZcyld09ShH5tUQncH0dUOCsMb/RLH37f3KZMV1qy3IWyh TUTLt8kMDp+ay0OBhKrVDKZs1SkNB+kMWqaMJMJaVKBoWZPba5W4/GeWBjmcvleSLx1v grOUUwe+Wwg4A82U2nrFOe6Xu0EjgLU1Hf4X/7Fc56Tb+d+79OBmRswBbJBjS6h/PU/h Dc27Nl/EPSfCiUmdqB2gBObH74RmyHYyA65+ko1SrXWi4JRwKKnWoc/B9l/FzC9GSita Mwv3gLXsX+BEVqJUy3moaBOWEeXJRkvdVFHLm1iYNz8/PhqawudoXsR/J0Xrcp2pAP3r gyEw== X-Gm-Message-State: AOAM533u+RFiLRo1w/+A+40H8lDKt0HXFuGVCK7+ax97Xcccdvt/wrIQ wwceg1sgHrQfYGpapuZHX+yVGQ== X-Google-Smtp-Source: ABdhPJzipImp2FJDXR65FI4cQBfU1/ZWv6fskJvunQo3KeiwYFfoMSTrdro0BQYaNbHlwWG5ksZP1g== X-Received: by 2002:a63:c049:: with SMTP id z9mr19741380pgi.353.1595365110347; Tue, 21 Jul 2020 13:58:30 -0700 (PDT) Received: from builder.lan (104-188-17-28.lightspeed.sndgca.sbcglobal.net. [104.188.17.28]) by smtp.gmail.com with ESMTPSA id z25sm21277934pfg.140.2020.07.21.13.58.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Jul 2020 13:58:29 -0700 (PDT) Date: Tue, 21 Jul 2020 13:56:35 -0700 From: Bjorn Andersson To: Siddharth Gupta Subject: Re: [PATCH v4 1/2] remoteproc: Add remoteproc character device interface Message-ID: <20200721205635.GM2922385@builder.lan> References: <1594148870-27276-1-git-send-email-sidgup@codeaurora.org> <1594148870-27276-2-git-send-email-sidgup@codeaurora.org> <20200715201839.GA3204081@xps15> <20200715215149.GA3267350@xps15> <81d7514c-727e-b4dc-e4ac-74a25966ccaf@codeaurora.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <81d7514c-727e-b4dc-e4ac-74a25966ccaf@codeaurora.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200721_165834_188358_0BB02649 X-CRM114-Status: GOOD ( 26.45 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ohad@wizery.com, tsoni@codeaurora.org, Mathieu Poirier , corbet@lwn.net, linux-arm-msm@vger.kernel.org, linux-doc@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org, agross@kernel.org, rishabhb@codeaurora.org, psodagud@codeaurora.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue 21 Jul 12:16 PDT 2020, Siddharth Gupta wrote: > On 7/15/2020 2:51 PM, Mathieu Poirier wrote: > > On Wed, Jul 15, 2020 at 02:18:39PM -0600, Mathieu Poirier wrote: > > > On Tue, Jul 07, 2020 at 12:07:49PM -0700, Siddharth Gupta wrote: [..] > > > > diff --git a/drivers/remoteproc/remoteproc_cdev.c b/drivers/remoteproc/remoteproc_cdev.c [..] > > > > +int rproc_char_device_add(struct rproc *rproc) > > > > +{ > > > > + int ret; > > > > + dev_t cdevt; > > > > + > > > > + cdev_init(&rproc->char_dev, &rproc_fops); > > > > + rproc->char_dev.owner = THIS_MODULE; > > > > + > > > > + cdevt = MKDEV(rproc_major, rproc->index); > > > > + ret = cdev_add(&rproc->char_dev, cdevt, 1); > > Trying this patchset on my side gave me the following splat[1]. After finding > > the root case I can't understand how you haven't see it on your side when you > > tested the feature. > > > > [1]. https://pastebin.com/aYTUUCdQ Mathieu, I've looked at this back and forth. Afaict this implies that rproc_major is still 0. Could it be that either alloc_chrdev_region() failed or somehow has yet to be called when you hit this point? > Hey Mathieu, > > We aren't able to reproduce the error that you are seeing, the splat is > coming > from the check for whiteout device[1] - which shouldn't happen because of > the > find_dynamic_major call[2], right? > > We are successfully seeing all our character device files and able to > successfully boot remoteprocs. From what I read and understood about > whiteout > devices they will be hidden in the fs. > > Could you provide more details about your configuration and testing? > > [1]: https://github.com/torvalds/linux/blob/master/fs/char_dev.c#L486 > > [2]: https://github.com/torvalds/linux/blob/master/fs/char_dev.c#L123 > > > > > > + if (ret < 0) > > > > + goto out; > > > > + > > > > + rproc->dev.devt = cdevt; > > > > +out: > > > > + return ret; > > > > +} > > > > + > > > > +void rproc_char_device_remove(struct rproc *rproc) > > > > +{ > > > > + __unregister_chrdev(rproc_major, rproc->index, 1, "remoteproc"); > > > > +} > > > > + > > > > +void __init rproc_init_cdev(void) > > > > +{ > > > > + int ret; > > > > + > > > > + ret = alloc_chrdev_region(&rproc_major, 0, NUM_RPROC_DEVICES, "remoteproc"); > > > > + if (ret < 0) > > > > + pr_err("Failed to alloc rproc_cdev region, err %d\n", ret); > > > > +} > > > > + > > > > +void __exit rproc_exit_cdev(void) > > > > +{ > > > > + unregister_chrdev_region(MKDEV(rproc_major, 0), NUM_RPROC_DEVICES); > > > Please go back to the comment I made on this during my last review and respin. > > After digging in the code while debugging the above problem, I don't see how > > unregistering the chrdev region the way it is done here would have worked. > Since this is compiled statically and not built as a module, we will never > exercise the code path, so I will remove it in the next patchset. > You're right Siddharth, since we changed CONFIG_REMOTEPROC to bool it's no longer possible to hit remoteproc_exit(), so you can omit this function entirely. (And we should clean up the rest of that as well) [..] > > > > diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h [..] > > > > @@ -488,6 +489,8 @@ struct rproc_dump_segment { > > > > * @auto_boot: flag to indicate if remote processor should be auto-started > > > > * @dump_segments: list of segments in the firmware > > > > * @nb_vdev: number of vdev currently handled by rproc > > > > + * @char_dev: character device of the rproc > > > > + * @cdev_put_on_release: flag to indicate if remoteproc should be shutdown on @char_dev release > > > > */ > > > > struct rproc { > > > > struct list_head node; > > > > @@ -523,6 +526,8 @@ struct rproc { > > > > int nb_vdev; > > > > u8 elf_class; > > > > u16 elf_machine; > > > > + struct cdev char_dev; As stated privately, I assumed based on this name that this is a struct device related to that character device. So please rename this cdev to save me from doing this mistake again. Thanks, Bjorn _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel