On Tue, Dec 8, 2015 at 2:53 PM, Lucas Stach <l.st...@pengutronix.de> wrote: > Hi Bjorn, > > Am Montag, den 07.12.2015, 21:33 -0600 schrieb Bjorn Helgaas: >> [+cc Jingoo (exynos), Richard, Lucas (imx6), Pratyush (spear13xx)] >> >> On Fri, Dec 04, 2015 at 11:22:50PM +0200, Grygorii Strashko wrote: >> > On 12/04/2015 08:46 PM, Bjorn Helgaas wrote: >> > > Hi Grygorii, > [...] >> > >> >> > >> + /* >> > >> + * Mark dra7xx_pcie_msi IRQ as IRQF_NO_THREAD >> > >> + * On -RT and if kernel is booting with "threadirqs" cmd line >> > >> parameter >> > >> + * the dra7xx_pcie_msi_irq_handler() will be forced threaded >> > >> but, >> > >> + * in the same time, it's IRQ dispatcher and calls >> > >> generic_handle_irq(), >> > >> + * which, in turn, will be resolved to handle_simple_irq() >> > >> call. >> > >> + * The handle_simple_irq() expected to be called with IRQ >> > >> disabled, as >> > >> + * result kernle will display warning: >> > >> + * "irq XXX handler YYY+0x0/0x14 enabled interrupts". >> > >> + */ >> > >> 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); >> > > >> > > There's similar code in exynos_add_pcie_port(), imx6_add_pcie_port(), >> > > and spear13xx_add_pcie_port(). Do they need similar changes? If not, >> > > why not? >> > > >> > > I see your discussion about DRA7 hardware design, but my impression is >> > > that this problem affects anybody who calls dw_handle_msi_irq() from a >> > > handler registered with IRQF_SHARED. >> > >> > Issue fixed by this patch is not related to IRQF_SHARED. >> > It will happen on -RT or if kernel will boot with "threadirqs" cmd line >> > parameter >> > - in both cases these PCI IRQ handlers will be forced to be threaded and, >> > as result, generic_handle_irq() will produce above backtrace. >> > >> > Personally, I don't have strong opinion about "should similar change be >> > applied >> > to other PCI drivers or not?" And I think, that owners of those driver >> > should >> > make such decision. >> >> If the same issue affects several drivers, I'd like to see them all >> handle it the same way. Otherwise, somebody coming along later will >> wonder why they're different, and there won't be a good answer. >> >> I cc'd the other maintainers to see what they think. >>
I too agree with the change for SPEAr13xx as well. ~Pratyush -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
