The patch titled genirq: warn when IRQF_DISABLED may be ignored has been removed from the -mm tree. Its filename was genirq-warn-when-irqf_disabled-may-be-ignored.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: genirq: warn when IRQF_DISABLED may be ignored From: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx> We periodically waste time tracking down problems from the genirq framework not respecting IRQF_DISABLED for some shared IRQ cases. Linus views this as "will not fix", but we're still left with the bugs caused by this misbehavior. This patch adds a nag message in request_irq(), so that drivers can fix their IRQ handlers to avoid this problem. Note that developers will never see the relevant bugs when they run with LOCKDEP, so it's no wonder these bugs are hard to find. (That also means LOCKDEP is overlooking some IRQ-related bugs involving IRQ handlers that don't set IRQF_DISABLED...) Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/irq/manage.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff -puN kernel/irq/manage.c~genirq-warn-when-irqf_disabled-may-be-ignored kernel/irq/manage.c --- a/kernel/irq/manage.c~genirq-warn-when-irqf_disabled-may-be-ignored +++ a/kernel/irq/manage.c @@ -671,6 +671,18 @@ int request_irq(unsigned int irq, irq_ha struct irq_desc *desc; int retval; + /* + * handle_IRQ_event() always ignores IRQF_DISABLED except for + * the _first_ irqaction (sigh). That can cause oopsing, but + * the behavior is classified as "will not fix" so we need to + * start nudging drivers away from using that idiom. + */ + if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) + == (IRQF_SHARED|IRQF_DISABLED)) + pr_warning("IRQ %d/%s: IRQF_DISABLED is not " + "guaranteed on shared IRQs\n", + irq, devname); + #ifdef CONFIG_LOCKDEP /* * Lockdep wants atomic interrupt handlers: _ Patches currently in -mm which might be from dbrownell@xxxxxxxxxxxxxxxxxxxxx are linux-next.patch acpi-fix-acpi_fadt_s4_rtc_wake-comment.patch genirq-record-irq_level-in-irq_desc.patch documentation-when-to-bug-and-when-to-not-bug.patch spi_gpio-driver.patch spi_gpio-driver-cleanups.patch atmel_spi-clean-up-spiv1-quirk-handling.patch spi-atmel_spi-update-chipselect-handling.patch spi-use-generic-gpio-calls-in-spi_s3c24xx_gpio.patch mfd-da903x-section-fix.patch rtc-ds1307-remove-legacy-probe-checks.patch rtc-bunch-of-drivers-fix-no-irq-case-handing.patch twl4030-gpio-cleanup-debounce.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html