From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:33592 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730051AbeIMTCa (ORCPT ); Thu, 13 Sep 2018 15:02:30 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Heiko Stuebner , Marc Zyngier , Olof Johansson , Sasha Levin Subject: [PATCH 4.18 046/197] iommu/rockchip: Move irq request past pm_runtime_enable Date: Thu, 13 Sep 2018 15:29:55 +0200 Message-Id: <20180913131843.388158321@linuxfoundation.org> In-Reply-To: <20180913131841.568116777@linuxfoundation.org> References: <20180913131841.568116777@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Zyngier [ Upstream commit 1aa55ca9b14af6cfd987ce4fdaf548f7067a5d07 ] Enabling the interrupt early, before power has been applied to the device, can result in an interrupt being delivered too early if: - the IOMMU shares an interrupt with a VOP - the VOP has a pending interrupt (after a kexec, for example) In these conditions, we end-up taking the interrupt without the IOMMU being ready to handle the interrupt (not powered on). Moving the interrupt request past the pm_runtime_enable() call makes sure we can at least access the IOMMU registers. Note that this is only a partial fix, and that the VOP interrupt will still be screaming until the VOP driver kicks in, which advocates for a more synchronized interrupt enabling/disabling approach. Fixes: 0f181d3cf7d98 ("iommu/rockchip: Add runtime PM support") Reviewed-by: Heiko Stuebner Signed-off-by: Marc Zyngier Signed-off-by: Olof Johansson Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/rockchip-iommu.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -1161,17 +1161,6 @@ static int rk_iommu_probe(struct platfor if (iommu->num_mmu == 0) return PTR_ERR(iommu->bases[0]); - i = 0; - while ((irq = platform_get_irq(pdev, i++)) != -ENXIO) { - if (irq < 0) - return irq; - - err = devm_request_irq(iommu->dev, irq, rk_iommu_irq, - IRQF_SHARED, dev_name(dev), iommu); - if (err) - return err; - } - iommu->reset_disabled = device_property_read_bool(dev, "rockchip,disable-mmu-reset"); @@ -1228,6 +1217,19 @@ static int rk_iommu_probe(struct platfor pm_runtime_enable(dev); + i = 0; + while ((irq = platform_get_irq(pdev, i++)) != -ENXIO) { + if (irq < 0) + return irq; + + err = devm_request_irq(iommu->dev, irq, rk_iommu_irq, + IRQF_SHARED, dev_name(dev), iommu); + if (err) { + pm_runtime_disable(dev); + goto err_remove_sysfs; + } + } + return 0; err_remove_sysfs: iommu_device_sysfs_remove(&iommu->iommu);