From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793829598; b=Hku0As/7tXdvDWIL7tUJfuK75KLXDi1xSaPu0kw14THOFdGC0Zvo3Bk45mqUJQg2ohSk 7B0Durvzl2VN/QVa5UuMDrtryi3ASqPpm2iDQylIrTSbeB4BKzmnE0S8XQ8zn2y9MLFTc o5vsfmc++CZfHJHTQqAhTlIJ/rJGftH+787fKIjm0LJ4Lm/zPWs8GT8Opb3l6LRk6Mpub rQL42KNoTi1H+pDUk/qjMFHkmr7lJbDPCg7m732+vozDLWdk5kgGAnQb1EV3hHuYhkD2b aUp86++O/Qoj41Sk/ofMsQ1JHVZkK6sqcObCEdRXxI6M7N7waoUUoJW6UPJ9o5jZ1xg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793829598; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=bschZ0puM7J7741sGXGlWSI/28seGSW9I3l970RuAtw=; b=rJlOAUX0C7aotFDlIdjvQ3lql/oc/2Lb3bQeG8YvzF/RmTG6wExQvxSMj3teT6zPPKu0 bb96PmWBwDn+KMSgBdavdGoppL1Qufob5Pf6+qqDg2k/5MohzI40uYHXmg20CVnkRxTOF 1Nfo5Fr91oFgxzgSVR2uansUU+8YVsD8vGwzG7p1zFZP9ARmS8lqsrdlkOVrUxVLkXL4M jsnN5xjJRpNUB3UIER5YxEi836KjApBHqDJgh2iEE/lquB1/8mv2O3uWC008FxUCO8iow IJ6HC6b/PoUSwsRV35BST3urbtoX3cu1CA8Oq6nLaD9Chzh5GITtY3mw5qiv4QKCsrw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Pogr+b2k; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 021E9606B2D2; Wed, 4 Nov 2026 21:59:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Pogr+b2k Received: by smtp.kernel.org (Postfix) with ESMTPSA id 904951F00A02; Wed, 4 Nov 2026 21:59:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793829597; bh=bschZ0puM7J7741sGXGlWSI/28seGSW9I3l970RuAtw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Pogr+b2kMd9pXPhtxRrB0/chx4oZT/Egw3sPWozLIVzqVqIP2KOU84a0ifOb/9m8t 7KKXJIj4B1OGHN+DQPTMU83nZdRVCGSrqm7/8rn6txfP1EB89nn+frjmUjmqaBImB4 zlueTLw8hPs10VjiWW2sXiknzXap4eHTZ89oEQgM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Konrad Dybcio , Mukesh Ojha , Will Deacon , Sasha Levin Subject: [PATCH 6.18 0227/1005] iommu/qcom: Enable clocks before hardware access in qcom_iommu_ctx_probe() Date: Wed, 4 Nov 2026 15:59:20 -0500 Message-ID: <20261104211050.191797494@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mukesh Ojha [ Upstream commit cb776a03a53429aa59e25a8cbc3d1a48bd11afdb ] qcom_iommu_ctx_probe() reads and writes the CB_FSR register to clear any stale IRQ left by the bootloader. This happens during devm_of_platform_populate() which is called from the parent device's probe before any pm_runtime_get(). The parent's clocks (iface, bus, tbu) are therefore not guaranteed to be on, making the register access unreliable on rebind or after a suspend cycle. Use pm_runtime_resume_and_get() on the parent device to ensure clocks are enabled before the register access, and release the reference immediately after. Reviewed-by: Konrad Dybcio Signed-off-by: Mukesh Ojha Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/arm-smmu/qcom_iommu.c index fbe4bd3ec0c42..792585321bd11 100644 --- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c +++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c @@ -704,8 +704,13 @@ static int qcom_iommu_ctx_probe(struct platform_device *pdev) /* clear IRQs before registering fault handler, just in case the * boot-loader left us a surprise: */ - if (!ctx->secured_ctx) + if (!ctx->secured_ctx) { + ret = pm_runtime_resume_and_get(dev->parent); + if (ret) + return ret; iommu_writel(ctx, ARM_SMMU_CB_FSR, iommu_readl(ctx, ARM_SMMU_CB_FSR)); + pm_runtime_put_sync(dev->parent); + } ret = devm_request_irq(dev, irq, qcom_iommu_fault, -- 2.53.0