Commit 62ebcda8 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

xen/events: Reduce irq_info:: Spurious_cnt storage size 



To prepare for interrupt spreading reduce the storage size of
irq_info::spurious_cnt to u8 so the required flag for the spreading logic
will not increase the storage size.

Protect the usage site against overruns.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/20201210194045.360198201@linutronix.de
parent f7a6f994

drivers/xen/events/events_base.c

+5 −3
Original line number Diff line number Diff line
@@ -95,7 +95,7 @@ struct irq_info { 
	struct list_head list;

	struct list_head eoi_list;

	short refcnt;

	short spurious_cnt;

	u8 spurious_cnt;

	enum xen_irq_type type; /* type */

	unsigned irq;

	evtchn_port_t evtchn;   /* event channel */
@@ -528,8 +528,10 @@ static void xen_irq_lateeoi_locked(struct irq_info *info, bool spurious) 
		return;



	if (spurious) {

		if ((1 << info->spurious_cnt) < (HZ << 2))

		if ((1 << info->spurious_cnt) < (HZ << 2)) {

			if (info->spurious_cnt != 0xFF)

				info->spurious_cnt++;

		}

		if (info->spurious_cnt > 1) {

			delay = 1 << (info->spurious_cnt - 2);

			if (delay > HZ)

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