From cdf278387fe97643c1feb5180b4fc3cb872286a0 Mon Sep 17 00:00:00 2001 From: marcel Date: Tue, 8 Feb 2011 01:49:30 +0000 Subject: In arm_get_next_irq(), use the last IRQ argument in order to prevent a hard hang due to an interrupt storm or stuck interrupt pin. We return the next IRQ that is larger than the last one returned and in doing so give all interrupts a fair chance of being handled. Consequently, we're able to break into the kernel debugger in such an event. --- sys/arm/mv/ic.c | 34 +++++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 11 deletions(-) (limited to 'sys/arm') diff --git a/sys/arm/mv/ic.c b/sys/arm/mv/ic.c index 83d43a1..14c6b7b 100644 --- a/sys/arm/mv/ic.c +++ b/sys/arm/mv/ic.c @@ -35,6 +35,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include #include @@ -143,27 +144,38 @@ static devclass_t mv_ic_devclass; DRIVER_MODULE(ic, simplebus, mv_ic_driver, mv_ic_devclass, 0, 0); int -arm_get_next_irq(int last __unused) +arm_get_next_irq(int last) { - int irq; + u_int filt, irq; + int next; + filt = ~((last >= 0) ? (2 << last) - 1 : 0); irq = mv_ic_get_cause() & mv_ic_get_mask(); - if (irq) - return (ffs(irq) - 1); - + if (irq & filt) { + next = ffs(irq & filt) - 1; + goto out; + } if (mv_ic_sc->ic_high_regs) { + filt = ~((last >= 32) ? (2 << (last - 32)) - 1 : 0); irq = mv_ic_get_cause_hi() & mv_ic_get_mask_hi(); - if (irq) - return (ffs(irq) + 31); + if (irq & filt) { + next = ffs(irq & filt) + 31; + goto out; + } } - if (mv_ic_sc->ic_error_regs) { + filt = ~((last >= 64) ? (2 << (last - 64)) - 1 : 0); irq = mv_ic_get_cause_error() & mv_ic_get_mask_error(); - if (irq) - return (ffs(irq) + 63); + if (irq & filt) { + next = ffs(irq & filt) + 63; + goto out; + } } + next = -1; - return (-1); + out: + CTR3(KTR_INTR, "%s: last=%d, next=%d", __func__, last, next); + return (next); } static void -- cgit v1.1