From 43d0b82bb45c32940f435e5e0001609e40af986e Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 15 Mar 2021 09:22:37 +0100 Subject: [PATCH] xen/events: reset affinity of 2-level event when tearing it down commit 9e77d96b8e2724ed00380189f7b0ded61113b39f upstream. When creating a new event channel with 2-level events the affinity needs to be reset initially in order to avoid using an old affinity from earlier usage of the event channel port. So when tearing an event channel down reset all affinity bits. The same applies to the affinity when onlining a vcpu: all old affinity settings for this vcpu must be reset. As percpu events get initialized before the percpu event channel hook is called, resetting of the affinities happens after offlining a vcpu (this is working, as initial percpu memory is zeroed out). Cc: stable@vger.kernel.org Reported-by: Julien Grall Signed-off-by: Juergen Gross Reviewed-by: Julien Grall Link: https://lore.kernel.org/r/20210306161833.4552-2-jgross@suse.com Signed-off-by: Boris Ostrovsky Signed-off-by: Greg Kroah-Hartman --- drivers/xen/events/events_2l.c | 15 +++++++++++++++ drivers/xen/events/events_base.c | 1 + drivers/xen/events/events_internal.h | 8 ++++++++ 3 files changed, 24 insertions(+) diff --git a/drivers/xen/events/events_2l.c b/drivers/xen/events/events_2l.c index f026624898e7a..cf3f579c1c3d4 100644 --- a/drivers/xen/events/events_2l.c +++ b/drivers/xen/events/events_2l.c @@ -47,6 +47,11 @@ static unsigned evtchn_2l_max_channels(void) return EVTCHN_2L_NR_CHANNELS; } +static void evtchn_2l_remove(evtchn_port_t evtchn, unsigned int cpu) +{ + clear_bit(evtchn, BM(per_cpu(cpu_evtchn_mask, cpu))); +} + static void evtchn_2l_bind_to_cpu(struct irq_info *info, unsigned cpu) { clear_bit(info->evtchn, BM(per_cpu(cpu_evtchn_mask, info->cpu))); @@ -354,9 +359,18 @@ static void evtchn_2l_resume(void) EVTCHN_2L_NR_CHANNELS/BITS_PER_EVTCHN_WORD); } +static int evtchn_2l_percpu_deinit(unsigned int cpu) +{ + memset(per_cpu(cpu_evtchn_mask, cpu), 0, sizeof(xen_ulong_t) * + EVTCHN_2L_NR_CHANNELS/BITS_PER_EVTCHN_WORD); + + return 0; +} + static const struct evtchn_ops evtchn_ops_2l = { .max_channels = evtchn_2l_max_channels, .nr_channels = evtchn_2l_max_channels, + .remove = evtchn_2l_remove, .bind_to_cpu = evtchn_2l_bind_to_cpu, .clear_pending = evtchn_2l_clear_pending, .set_pending = evtchn_2l_set_pending, @@ -366,6 +380,7 @@ static const struct evtchn_ops evtchn_ops_2l = { .unmask = evtchn_2l_unmask, .handle_events = evtchn_2l_handle_events, .resume = evtchn_2l_resume, + .percpu_deinit = evtchn_2l_percpu_deinit, }; void __init xen_evtchn_2l_init(void) diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 7b94a6c316643..2e4c4ab38095e 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -286,6 +286,7 @@ static int xen_irq_info_pirq_setup(unsigned irq, static void xen_irq_info_cleanup(struct irq_info *info) { set_evtchn_to_irq(info->evtchn, -1); + xen_evtchn_port_remove(info->evtchn, info->cpu); info->evtchn = 0; } diff --git a/drivers/xen/events/events_internal.h b/drivers/xen/events/events_internal.h index a35c8c7ac6066..6ccebc4986790 100644 --- a/drivers/xen/events/events_internal.h +++ b/drivers/xen/events/events_internal.h @@ -65,6 +65,7 @@ struct evtchn_ops { unsigned (*nr_channels)(void); int (*setup)(struct irq_info *info); + void (*remove)(evtchn_port_t port, unsigned int cpu); void (*bind_to_cpu)(struct irq_info *info, unsigned cpu); void (*clear_pending)(unsigned port); @@ -107,6 +108,13 @@ static inline int xen_evtchn_port_setup(struct irq_info *info) return 0; } +static inline void xen_evtchn_port_remove(evtchn_port_t evtchn, + unsigned int cpu) +{ + if (evtchn_ops->remove) + evtchn_ops->remove(evtchn, cpu); +} + static inline void xen_evtchn_port_bind_to_cpu(struct irq_info *info, unsigned cpu) {