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=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 A15E7C4338F for ; Fri, 6 Aug 2021 14:11:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E36860EE5 for ; Fri, 6 Aug 2021 14:11:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237211AbhHFOMB (ORCPT ); Fri, 6 Aug 2021 10:12:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:53058 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235847AbhHFOMA (ORCPT ); Fri, 6 Aug 2021 10:12:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 740FF611C5 for ; Fri, 6 Aug 2021 14:11:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628259104; bh=CSbLfRVE2UUWpruHwkg8Uj8Y4BhMu1P18wZvcPO6wpo=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=NjbxXJRLfzOCZp/OsanZtKa0LYJmDvliEHis1OXyMPWXO5f7DC1LsIedH1xOOTmdq LYrLKU1u2fD/w2/tQxOPQ0aVv0hqOfu/h2HynCrM8b7ralpEdpdGMAtgDCAPqTQC30 d9Ljf/Ffd4LumowMEv886W/09GGFGcNZp2VJ+NkL7EzB5qz/We243LRuMZ+V86PKxE uZ7p1GLaaZoOf+4U+YEdwlIpcmbKvho8osS8UzH7wRG0L4aq0FN0szRecGJeKA0r3p jC/MPaEhIqnKp9ELYIOkWYt52b7iaeoI3WXeRLL0KcXgnfzqCG9dq8IKieehuJErZg gAumwMZcALE3g== Received: by mail-ej1-f42.google.com with SMTP id qk33so15240472ejc.12 for ; Fri, 06 Aug 2021 07:11:44 -0700 (PDT) X-Gm-Message-State: AOAM530gfh4r7n5L5U1Ktvuh4BObFNaSO7EYsmgbdpWg2LNBTrWDFgtS 1dvMy5FFtdg8Nj14qP8GB4+LNK83N+2IVscCOw== X-Google-Smtp-Source: ABdhPJz2aB9W+k5EFME8idlFEFePLvrE7JvKCrPX4gmCiv3PpMHVunwV0NzEcLofGEPyHNTiQyH37b4B3lAcTf8hS2o= X-Received: by 2002:a17:906:d287:: with SMTP id ay7mr9680139ejb.360.1628259102955; Fri, 06 Aug 2021 07:11:42 -0700 (PDT) MIME-Version: 1.0 References: <20210805094736.902-1-will@kernel.org> In-Reply-To: <20210805094736.902-1-will@kernel.org> From: Rob Herring Date: Fri, 6 Aug 2021 08:11:31 -0600 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] of: restricted dma: Don't fail device probe on rmem init failure To: Will Deacon Cc: "linux-kernel@vger.kernel.org" , Linux IOMMU , Claire Chang , Konrad Rzeszutek Wilk , Robin Murphy , Christoph Hellwig Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 5, 2021 at 3:47 AM Will Deacon wrote: > > If CONFIG_DMA_RESTRICTED_POOL=n then probing a device with a reference > to a "restricted-dma-pool" will fail with a reasonably cryptic error: I'm left wondering why of_dma_set_restricted_buffer() is even enabled with CONFIG_DMA_RESTRICTED_POOL=n. of_dma_set_restricted_buffer() should use IS_ENABLED and it should also be moved to of/device.c. There's no reason for it to be in of/address.c. It has nothing to do with address parsing. > | pci-host-generic: probe of 10000.pci failed with error -22 > > Print a more helpful message in this case and try to continue probing > the device as we do if the kernel doesn't have the restricted DMA patches > applied or either CONFIG_OF_ADDRESS or CONFIG_HAS_DMA =n. I think you'd have to work pretty hard to hit this code path with either of the above config options off. > Cc: Claire Chang > Cc: Konrad Rzeszutek Wilk > Cc: Robin Murphy > Cc: Christoph Hellwig > Cc: Rob Herring > Signed-off-by: Will Deacon > --- > drivers/of/address.c | 8 ++++---- > drivers/of/device.c | 2 +- > drivers/of/of_private.h | 8 +++----- > 3 files changed, 8 insertions(+), 10 deletions(-) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 973257434398..f6bf4b423c2a 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -997,7 +997,7 @@ int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map) > return ret; > } > > -int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np) > +void of_dma_set_restricted_buffer(struct device *dev, struct device_node *np) > { > struct device_node *node, *of_node = dev->of_node; > int count, i; > @@ -1022,11 +1022,11 @@ int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np) > */ > if (of_device_is_compatible(node, "restricted-dma-pool") && > of_device_is_available(node)) > - return of_reserved_mem_device_init_by_idx(dev, of_node, > - i); > + break; > } > > - return 0; > + if (i != count && of_reserved_mem_device_init_by_idx(dev, of_node, i)) > + dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n"); > } > #endif /* CONFIG_HAS_DMA */ > > diff --git a/drivers/of/device.c b/drivers/of/device.c > index 2defdca418ec..258a2b099410 100644 > --- a/drivers/of/device.c > +++ b/drivers/of/device.c > @@ -166,7 +166,7 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, > arch_setup_dma_ops(dev, dma_start, size, iommu, coherent); > > if (!iommu) > - return of_dma_set_restricted_buffer(dev, np); > + of_dma_set_restricted_buffer(dev, np); > > return 0; > } > diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h > index f557bd22b0cf..bc883f69496b 100644 > --- a/drivers/of/of_private.h > +++ b/drivers/of/of_private.h > @@ -163,18 +163,16 @@ struct bus_dma_region; > #if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA) > int of_dma_get_range(struct device_node *np, > const struct bus_dma_region **map); > -int of_dma_set_restricted_buffer(struct device *dev, struct device_node *np); > +void of_dma_set_restricted_buffer(struct device *dev, struct device_node *np); > #else > static inline int of_dma_get_range(struct device_node *np, > const struct bus_dma_region **map) > { > return -ENODEV; > } > -static inline int of_dma_set_restricted_buffer(struct device *dev, > - struct device_node *np) > +static inline void of_dma_set_restricted_buffer(struct device *dev, > + struct device_node *np) > { > - /* Do nothing, successfully. */ > - return 0; > } > #endif > > -- > 2.32.0.605.g8dce9f2422-goog >