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author | Grygorii Strashko <grygorii.strashko@ti.com> | 2015-12-10 21:18:20 +0200 |
---|---|---|
committer | Sasha Levin <sasha.levin@oracle.com> | 2016-02-09 22:56:22 -0500 |
commit | 05ff846473bc8b32254899c2b1a55ac7cc37e6d3 (patch) | |
tree | 9cfa6086e3a4f64237c17adf95486235e761871d | |
parent | f190994a35f61b4a538ee97991262eed09333493 (diff) | |
download | lwn-05ff846473bc8b32254899c2b1a55ac7cc37e6d3.tar.gz lwn-05ff846473bc8b32254899c2b1a55ac7cc37e6d3.zip |
PCI: host: Mark PCIe/PCI (MSI) IRQ cascade handlers as IRQF_NO_THREAD
[ Upstream commit 8ff0ef996ca00028519c70e8d51d32bd37eb51dc ]
On -RT and if kernel is booting with "threadirqs" cmd line parameter,
PCIe/PCI (MSI) IRQ cascade handlers (like dra7xx_pcie_msi_irq_handler())
will be forced threaded and, as result, will generate warnings like this:
WARNING: CPU: 1 PID: 82 at kernel/irq/handle.c:150 handle_irq_event_percpu+0x14c/0x174()
irq 460 handler irq_default_primary_handler+0x0/0x14 enabled interrupts
Backtrace:
(warn_slowpath_common) from (warn_slowpath_fmt+0x38/0x40)
(warn_slowpath_fmt) from (handle_irq_event_percpu+0x14c/0x174)
(handle_irq_event_percpu) from (handle_irq_event+0x84/0xb8)
(handle_irq_event) from (handle_simple_irq+0x90/0x118)
(handle_simple_irq) from (generic_handle_irq+0x30/0x44)
(generic_handle_irq) from (dra7xx_pcie_msi_irq_handler+0x7c/0x8c)
(dra7xx_pcie_msi_irq_handler) from (irq_forced_thread_fn+0x28/0x5c)
(irq_forced_thread_fn) from (irq_thread+0x128/0x204)
This happens because all of them invoke generic_handle_irq() from the
requested handler. generic_handle_irq() grabs raw_locks and thus needs to
run in raw-IRQ context.
This issue was originally reproduced on TI dra7-evem, but, as was
identified during discussion [1], other hosts can also suffer from this
issue. Fix all them at once by marking PCIe/PCI (MSI) IRQ cascade handlers
IRQF_NO_THREAD explicitly.
[1] http://lkml.kernel.org/r/1448027966-21610-1-git-send-email-grygorii.strashko@ti.com
[bhelgaas: add stable tag, fix typos]
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Lucas Stach <l.stach@pengutronix.de> (for imx6)
CC: stable@vger.kernel.org
CC: Kishon Vijay Abraham I <kishon@ti.com>
CC: Jingoo Han <jingoohan1@gmail.com>
CC: Kukjin Kim <kgene@kernel.org>
CC: Krzysztof Kozlowski <k.kozlowski@samsung.com>
CC: Richard Zhu <Richard.Zhu@freescale.com>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Stephen Warren <swarren@wwwdotorg.org>
CC: Alexandre Courbot <gnurou@gmail.com>
CC: Simon Horman <horms@verge.net.au>
CC: Pratyush Anand <pratyush.anand@gmail.com>
CC: Michal Simek <michal.simek@xilinx.com>
CC: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
CC: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
-rw-r--r-- | drivers/pci/host/pci-dra7xx.c | 3 | ||||
-rw-r--r-- | drivers/pci/host/pci-exynos.c | 3 | ||||
-rw-r--r-- | drivers/pci/host/pci-imx6.c | 3 | ||||
-rw-r--r-- | drivers/pci/host/pci-tegra.c | 2 | ||||
-rw-r--r-- | drivers/pci/host/pcie-rcar.c | 6 | ||||
-rw-r--r-- | drivers/pci/host/pcie-spear13xx.c | 3 | ||||
-rw-r--r-- | drivers/pci/host/pcie-xilinx.c | 3 |
7 files changed, 15 insertions, 8 deletions
diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci-dra7xx.c index 52b34fee07fd..b2d093ea5ff2 100644 --- a/drivers/pci/host/pci-dra7xx.c +++ b/drivers/pci/host/pci-dra7xx.c @@ -289,7 +289,8 @@ static int add_pcie_port(struct dra7xx_pcie *dra7xx, } ret = devm_request_irq(&pdev->dev, pp->irq, - dra7xx_pcie_msi_irq_handler, IRQF_SHARED, + dra7xx_pcie_msi_irq_handler, + IRQF_SHARED | IRQF_NO_THREAD, "dra7-pcie-msi", pp); if (ret) { dev_err(&pdev->dev, "failed to request irq\n"); diff --git a/drivers/pci/host/pci-exynos.c b/drivers/pci/host/pci-exynos.c index c5d0ca384502..ab8bcaabaf21 100644 --- a/drivers/pci/host/pci-exynos.c +++ b/drivers/pci/host/pci-exynos.c @@ -535,7 +535,8 @@ static int __init add_pcie_port(struct pcie_port *pp, ret = devm_request_irq(&pdev->dev, pp->msi_irq, exynos_pcie_msi_irq_handler, - IRQF_SHARED, "exynos-pcie", pp); + IRQF_SHARED | IRQF_NO_THREAD, + "exynos-pcie", pp); if (ret) { dev_err(&pdev->dev, "failed to request msi irq\n"); return ret; diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index d1a26d17b586..f1f239f60685 100644 --- a/drivers/pci/host/pci-imx6.c +++ b/drivers/pci/host/pci-imx6.c @@ -534,7 +534,8 @@ static int __init imx6_add_pcie_port(struct pcie_port *pp, ret = devm_request_irq(&pdev->dev, pp->msi_irq, imx6_pcie_msi_handler, - IRQF_SHARED, "mx6-pcie-msi", pp); + IRQF_SHARED | IRQF_NO_THREAD, + "mx6-pcie-msi", pp); if (ret) { dev_err(&pdev->dev, "failed to request MSI irq\n"); return -ENODEV; diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c index 19bb19c7db4a..2898f1597c84 100644 --- a/drivers/pci/host/pci-tegra.c +++ b/drivers/pci/host/pci-tegra.c @@ -1374,7 +1374,7 @@ static int tegra_pcie_enable_msi(struct tegra_pcie *pcie) msi->irq = err; - err = request_irq(msi->irq, tegra_pcie_msi_irq, 0, + err = request_irq(msi->irq, tegra_pcie_msi_irq, IRQF_NO_THREAD, tegra_msi_irq_chip.name, pcie); if (err < 0) { dev_err(&pdev->dev, "failed to request IRQ: %d\n", err); diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c index 61158e03ab5f..bfab844f772d 100644 --- a/drivers/pci/host/pcie-rcar.c +++ b/drivers/pci/host/pcie-rcar.c @@ -704,14 +704,16 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie) /* Two irqs are for MSI, but they are also used for non-MSI irqs */ err = devm_request_irq(&pdev->dev, msi->irq1, rcar_pcie_msi_irq, - IRQF_SHARED, rcar_msi_irq_chip.name, pcie); + IRQF_SHARED | IRQF_NO_THREAD, + rcar_msi_irq_chip.name, pcie); if (err < 0) { dev_err(&pdev->dev, "failed to request IRQ: %d\n", err); goto err; } err = devm_request_irq(&pdev->dev, msi->irq2, rcar_pcie_msi_irq, - IRQF_SHARED, rcar_msi_irq_chip.name, pcie); + IRQF_SHARED | IRQF_NO_THREAD, + rcar_msi_irq_chip.name, pcie); if (err < 0) { dev_err(&pdev->dev, "failed to request IRQ: %d\n", err); goto err; diff --git a/drivers/pci/host/pcie-spear13xx.c b/drivers/pci/host/pcie-spear13xx.c index b4ba6ff56cf6..925cfbad5be6 100644 --- a/drivers/pci/host/pcie-spear13xx.c +++ b/drivers/pci/host/pcie-spear13xx.c @@ -280,7 +280,8 @@ static int add_pcie_port(struct pcie_port *pp, struct platform_device *pdev) return -ENODEV; } ret = devm_request_irq(dev, pp->irq, spear13xx_pcie_irq_handler, - IRQF_SHARED, "spear1340-pcie", pp); + IRQF_SHARED | IRQF_NO_THREAD, + "spear1340-pcie", pp); if (ret) { dev_err(dev, "failed to request irq %d\n", pp->irq); return ret; diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c index ccc496b33a97..0b68a45a8d97 100644 --- a/drivers/pci/host/pcie-xilinx.c +++ b/drivers/pci/host/pcie-xilinx.c @@ -859,7 +859,8 @@ static int xilinx_pcie_parse_dt(struct xilinx_pcie_port *port) port->irq = irq_of_parse_and_map(node, 0); err = devm_request_irq(dev, port->irq, xilinx_pcie_intr_handler, - IRQF_SHARED, "xilinx-pcie", port); + IRQF_SHARED | IRQF_NO_THREAD, + "xilinx-pcie", port); if (err) { dev_err(dev, "unable to request irq %d\n", port->irq); return err; |