From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27A4B318ED6 for ; Mon, 20 Jul 2026 15:02:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784559768; cv=none; b=He1uNfFpaLxnE3TCmPW7FK2Mov6zLiXxQyBgFaGzcu0pUhr/bQj8XV5SJJLuUmXk+xdMTHJp5lbS1NNC5AriUuratdz9oWyK1VgJY4SXBcEuUtALqBI49BULDOKUetPmsuF0sjqCocQ2aDJSlGiBaemSklPt7kHpn+yN4+7/e0c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784559768; c=relaxed/simple; bh=9Jm5yGC7CqtvFMVmRbUk2Jaec15aGe8QsBNTh3IE9GA=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=Nk/WCBgReinrmuLn8a1GZKHDjUUlMO4Xg1W7Q1D6l6RH0DzSnKgEgQMBPhZDcMqhxBs3l0uNtEIexwyiUOREyCN99SobxBrWoH9gzmnBaXYniKX0xHaYGo4dFTLW94miSw3DFs3A+QppcHbVLb0VBIupAQT0J5IrGSpyNGkZ+nA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=amWDLWQS; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="amWDLWQS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D6CB1F000E9; Mon, 20 Jul 2026 15:02:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784559767; bh=Pdt9j2xhnvIhw1HpusAgUvmRUMt/RECaODcfOHB7J38=; h=Subject:To:Cc:From:Date; b=amWDLWQSeb4UUiJhvOEcqPcq6le3VU32j49xGUJvRazvVI7bswJ1lXMdkT0bUrVRb dW824kM5HHX3zDOvGQq2K9zEEHJiQywCXXEUfYs6iK8QoogPyiQpbI8F+10zyNAotV EBkMdmoQY9JK14yo7iuc6BCt0+iLdeyVyzGemvKw= Subject: FAILED: patch "[PATCH] dmaengine: sh: rz-dmac: Move interrupt request after" failed to apply to 6.18-stable tree To: claudiu.beznea.uj@bp.renesas.com,Frank.Li@nxp.com,john.madieu.xa@bp.renesas.com,tommaso.merciai.xr@bp.renesas.com,vkoul@kernel.org Cc: From: Date: Mon, 20 Jul 2026 17:02:20 +0200 Message-ID: <2026072020-swampland-tavern-478c@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y git checkout FETCH_HEAD git cherry-pick -x 731712403ddb39d1a76a11abf339a0615bc85de7 # git commit -s git send-email --to '' --in-reply-to '2026072020-swampland-tavern-478c@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 731712403ddb39d1a76a11abf339a0615bc85de7 Mon Sep 17 00:00:00 2001 From: Claudiu Beznea Date: Tue, 26 May 2026 11:46:53 +0300 Subject: [PATCH] dmaengine: sh: rz-dmac: Move interrupt request after everything is set up Once the interrupt is requested, the interrupt handler may run immediately. Since the IRQ handler can access channel->ch_base, which is initialized only after requesting the IRQ, this may lead to invalid memory access. Likewise, the IRQ thread may access uninitialized data (the ld_free, ld_queue, and ld_active lists), which may also lead to issues. Request the interrupts only after everything is set up. To keep the error path simpler, use dmam_alloc_coherent() instead of dma_alloc_coherent(). Fixes: 5000d37042a6 ("dmaengine: sh: Add DMAC driver for RZ/G2L SoC") Cc: stable@vger.kernel.org Reviewed-by: Frank Li Tested-by: John Madieu Signed-off-by: Claudiu Beznea Tested-by: Tommaso Merciai Link: https://patch.msgid.link/20260526084710.3491480-2-claudiu.beznea@kernel.org Signed-off-by: Vinod Koul diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c index 625ff29024de..9f206a33dcc6 100644 --- a/drivers/dma/sh/rz-dmac.c +++ b/drivers/dma/sh/rz-dmac.c @@ -981,25 +981,6 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, channel->index = index; channel->mid_rid = -EINVAL; - /* Request the channel interrupt. */ - scnprintf(pdev_irqname, sizeof(pdev_irqname), "ch%u", index); - irq = platform_get_irq_byname(pdev, pdev_irqname); - if (irq < 0) - return irq; - - irqname = devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u", - dev_name(dmac->dev), index); - if (!irqname) - return -ENOMEM; - - ret = devm_request_threaded_irq(dmac->dev, irq, rz_dmac_irq_handler, - rz_dmac_irq_handler_thread, 0, - irqname, channel); - if (ret) { - dev_err(dmac->dev, "failed to request IRQ %u (%d)\n", irq, ret); - return ret; - } - /* Set io base address for each channel */ if (index < 8) { channel->ch_base = dmac->base + CHANNEL_0_7_OFFSET + @@ -1012,9 +993,9 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, } /* Allocate descriptors */ - lmdesc = dma_alloc_coherent(&pdev->dev, - sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, - &channel->lmdesc.base_dma, GFP_KERNEL); + lmdesc = dmam_alloc_coherent(&pdev->dev, + sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, + &channel->lmdesc.base_dma, GFP_KERNEL); if (!lmdesc) { dev_err(&pdev->dev, "Can't allocate memory (lmdesc)\n"); return -ENOMEM; @@ -1030,7 +1011,24 @@ static int rz_dmac_chan_probe(struct rz_dmac *dmac, INIT_LIST_HEAD(&channel->ld_free); INIT_LIST_HEAD(&channel->ld_active); - return 0; + /* Request the channel interrupt. */ + scnprintf(pdev_irqname, sizeof(pdev_irqname), "ch%u", index); + irq = platform_get_irq_byname(pdev, pdev_irqname); + if (irq < 0) + return irq; + + irqname = devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u", + dev_name(dmac->dev), index); + if (!irqname) + return -ENOMEM; + + ret = devm_request_threaded_irq(dmac->dev, irq, rz_dmac_irq_handler, + rz_dmac_irq_handler_thread, 0, + irqname, channel); + if (ret) + dev_err(dmac->dev, "failed to request IRQ %u (%d)\n", irq, ret); + + return ret; } static void rz_dmac_put_device(void *_dev) @@ -1099,7 +1097,6 @@ static int rz_dmac_probe(struct platform_device *pdev) const char *irqname = "error"; struct dma_device *engine; struct rz_dmac *dmac; - int channel_num; int ret; int irq; u8 i; @@ -1132,18 +1129,6 @@ static int rz_dmac_probe(struct platform_device *pdev) return PTR_ERR(dmac->ext_base); } - /* Register interrupt handler for error */ - irq = platform_get_irq_byname_optional(pdev, irqname); - if (irq > 0) { - ret = devm_request_irq(&pdev->dev, irq, rz_dmac_irq_handler, 0, - irqname, NULL); - if (ret) { - dev_err(&pdev->dev, "failed to request IRQ %u (%d)\n", - irq, ret); - return ret; - } - } - /* Initialize the channels. */ INIT_LIST_HEAD(&dmac->engine.channels); @@ -1169,6 +1154,18 @@ static int rz_dmac_probe(struct platform_device *pdev) goto err; } + /* Register interrupt handler for error */ + irq = platform_get_irq_byname_optional(pdev, irqname); + if (irq > 0) { + ret = devm_request_irq(&pdev->dev, irq, rz_dmac_irq_handler, 0, + irqname, NULL); + if (ret) { + dev_err(&pdev->dev, "failed to request IRQ %u (%d)\n", + irq, ret); + goto err; + } + } + /* Register the DMAC as a DMA provider for DT. */ ret = of_dma_controller_register(pdev->dev.of_node, rz_dmac_of_xlate, NULL); @@ -1210,16 +1207,6 @@ static int rz_dmac_probe(struct platform_device *pdev) dma_register_err: of_dma_controller_free(pdev->dev.of_node); err: - channel_num = i ? i - 1 : 0; - for (i = 0; i < channel_num; i++) { - struct rz_dmac_chan *channel = &dmac->channels[i]; - - dma_free_coherent(&pdev->dev, - sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, - channel->lmdesc.base, - channel->lmdesc.base_dma); - } - reset_control_assert(dmac->rstc); err_pm_runtime_put: pm_runtime_put(&pdev->dev); @@ -1232,18 +1219,9 @@ static int rz_dmac_probe(struct platform_device *pdev) static void rz_dmac_remove(struct platform_device *pdev) { struct rz_dmac *dmac = platform_get_drvdata(pdev); - unsigned int i; dma_async_device_unregister(&dmac->engine); of_dma_controller_free(pdev->dev.of_node); - for (i = 0; i < dmac->n_channels; i++) { - struct rz_dmac_chan *channel = &dmac->channels[i]; - - dma_free_coherent(&pdev->dev, - sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, - channel->lmdesc.base, - channel->lmdesc.base_dma); - } reset_control_assert(dmac->rstc); pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev);