Re: [PATCH 0/2] irq: detect slow IRQ handlers

2021-01-13 Thread Paul E. McKenney
On Wed, Jan 13, 2021 at 12:39:15PM +, Mark Rutland wrote: > On Tue, Jan 12, 2021 at 04:09:53PM -0800, Paul E. McKenney wrote: > > On Tue, Jan 12, 2021 at 01:59:48PM +, Mark Rutland wrote: > > > Hi, > > > > > > While fuzzing arm64 with Syzkaller (under QEMU+KVM) over a number of > > > rele

Re: [PATCH 0/2] irq: detect slow IRQ handlers

2021-01-13 Thread Mark Rutland
On Tue, Jan 12, 2021 at 04:09:53PM -0800, Paul E. McKenney wrote: > On Tue, Jan 12, 2021 at 01:59:48PM +, Mark Rutland wrote: > > Hi, > > > > While fuzzing arm64 with Syzkaller (under QEMU+KVM) over a number of > > releases, > > I've occasionally seen some ridiculously long stalls (20+ second

Re: [PATCH 0/2] irq: detect slow IRQ handlers

2021-01-12 Thread Paul E. McKenney
On Tue, Jan 12, 2021 at 01:59:48PM +, Mark Rutland wrote: > Hi, > > While fuzzing arm64 with Syzkaller (under QEMU+KVM) over a number of releases, > I've occasionally seen some ridiculously long stalls (20+ seconds), where it > appears that a CPU is stuck in a hard IRQ context. As this gets de

[PATCH 0/2] irq: detect slow IRQ handlers

2021-01-12 Thread Mark Rutland
Hi, While fuzzing arm64 with Syzkaller (under QEMU+KVM) over a number of releases, I've occasionally seen some ridiculously long stalls (20+ seconds), where it appears that a CPU is stuck in a hard IRQ context. As this gets detected after the CPU returns to the interrupted context, it's difficult