Commits
Will Deacon committed b08e5fd90bf
arm_pmu: Use disable_irq_nosync when disabling SPI in CPU teardown hook Commit 6de3f79112cc ("arm_pmu: explicitly enable/disable SPIs at hotplug") moved all of the arm_pmu IRQ enable/disable calls to the CPU hotplug hooks, regardless of whether they are implemented as PPIs or SPIs. This can lead to us sleeping from atomic context due to disable_irq blocking: | BUG: sleeping function called from invalid context at kernel/irq/manage.c:112 | in_atomic(): 1, irqs_disabled(): 128, pid: 15, name: migration/1 | no locks held by migration/1/15. | irq event stamp: 192 | hardirqs last enabled at (191): [<00000000803c2507>] | _raw_spin_unlock_irq+0x2c/0x4c | hardirqs last disabled at (192): [<000000007f57ad28>] multi_cpu_stop+0x9c/0x140 | softirqs last enabled at (0): [<0000000004ee1b58>] | copy_process.isra.77.part.78+0x43c/0x1504 | softirqs last disabled at (0): [< (null)>] (null) | CPU: 1 PID: 15 Comm: migration/1 Not tainted 4.16.0-rc3-salvator-x #1651 | Hardware name: Renesas Salvator-X board based on r8a7796 (DT) | Call trace: | dump_backtrace+0x0/0x140 | show_stack+0x14/0x1c | dump_stack+0xb4/0xf0 | ___might_sleep+0x1fc/0x218 | __might_sleep+0x70/0x80 | synchronize_irq+0x40/0xa8 | disable_irq+0x20/0x2c | arm_perf_teardown_cpu+0x80/0xac Since the interrupt is always CPU-affine and this code is running with interrupts disabled, we can just use disable_irq_nosync as we know there isn't a concurrent invocation of the handler to worry about. Fixes: 6de3f79112cc ("arm_pmu: explicitly enable/disable SPIs at hotplug") Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>