[PATCH 4.13 019/110] genirq: Fix cpumask check in __irq_startup_managed()

From: Greg Kroah-Hartman
Date: Tue Oct 03 2017 - 08:54:55 EST


4.13-stable review patch. If anyone has any objections, please let me know.

------------------

From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

commit 9cb067ef8a10bb13112e4d1c0ea996ec96527422 upstream.

The result of cpumask_any_and() is invalid when result greater or equal
nr_cpu_ids. The current check is checking for greater only. Fix it.

Fixes: 761ea388e8c4 ("genirq: Handle managed irqs gracefully in irq_startup()")
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Chen Yu <yu.c.chen@xxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: Alok Kataria <akataria@xxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Rui Zhang <rui.zhang@xxxxxxxxx>
Cc: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Len Brown <lenb@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20170913213152.272283444@xxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
kernel/irq/chip.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -202,7 +202,7 @@ __irq_startup_managed(struct irq_desc *d

irqd_clr_managed_shutdown(d);

- if (cpumask_any_and(aff, cpu_online_mask) > nr_cpu_ids) {
+ if (cpumask_any_and(aff, cpu_online_mask) >= nr_cpu_ids) {
/*
* Catch code which fiddles with enable_irq() on a managed
* and potentially shutdown IRQ. Chained interrupt