From: Juergen Gross <jgross@xxxxxxxx>
commit 0891fb39ba67bd7ae023ea0d367297ffff010781 upstream.
Since commit c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.")
Xen is using the chip_data pointer for storing IRQ specific data. When
running as a HVM domain this can result in problems for legacy IRQs, as
those might use chip_data for their own purposes.
Use a local array for this purpose in case of legacy IRQs, avoiding the
double use.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: c330fb1ddc0a ("XEN uses irqdesc::irq_data_common::handler_data to store a per interrupt XEN data pointer which contains XEN specific information.")
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Tested-by: Stefan Bader <stefan.bader@xxxxxxxxxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20200930091614.13660-1-jgross@xxxxxxxx
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <benh@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/xen/events/events_base.c | 29 +++++++++++++++++++++--------
1 file changed, 21 insertions(+), 8 deletions(-)
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -91,6 +91,8 @@ static bool (*pirq_needs_eoi)(unsigned i
/* Xen will never allocate port zero for any purpose. */
#define VALID_EVTCHN(chn) ((chn) != 0)
+static struct irq_info *legacy_info_ptrs[NR_IRQS_LEGACY];
+
static struct irq_chip xen_dynamic_chip;
static struct irq_chip xen_percpu_chip;
static struct irq_chip xen_pirq_chip;
@@ -155,7 +157,18 @@ int get_evtchn_to_irq(unsigned evtchn)
/* Get info for IRQ */
struct irq_info *info_for_irq(unsigned irq)
{
- return irq_get_chip_data(irq);
+ if (irq < nr_legacy_irqs())
+ return legacy_info_ptrs[irq];
+ else
+ return irq_get_chip_data(irq);
+}
+
+static void set_info_for_irq(unsigned int irq, struct irq_info *info)
+{
+ if (irq < nr_legacy_irqs())
+ legacy_info_ptrs[irq] = info;
+ else
+ irq_set_chip_data(irq, info);
}
/* Constructors for packed IRQ information. */
@@ -384,7 +397,7 @@ static void xen_irq_init(unsigned irq)
info->type = IRQT_UNBOUND;
info->refcnt = -1;
- irq_set_chip_data(irq, info);
+ set_info_for_irq(irq, info);
list_add_tail(&info->list, &xen_irq_list_head);
}
@@ -433,14 +446,14 @@ static int __must_check xen_allocate_irq
static void xen_free_irq(unsigned irq)
{
- struct irq_info *info = irq_get_chip_data(irq);
+ struct irq_info *info = info_for_irq(irq);
if (WARN_ON(!info))
return;
list_del(&info->list);
- irq_set_chip_data(irq, NULL);
+ set_info_for_irq(irq, NULL);
WARN_ON(info->refcnt > 0);
@@ -610,7 +623,7 @@ EXPORT_SYMBOL_GPL(xen_irq_from_gsi);
static void __unbind_from_irq(unsigned int irq)
{
int evtchn = evtchn_from_irq(irq);
- struct irq_info *info = irq_get_chip_data(irq);
+ struct irq_info *info = info_for_irq(irq);
if (info->refcnt > 0) {
info->refcnt--;
@@ -1114,7 +1127,7 @@ int bind_ipi_to_irqhandler(enum ipi_vect
void unbind_from_irqhandler(unsigned int irq, void *dev_id)
{
- struct irq_info *info = irq_get_chip_data(irq);
+ struct irq_info *info = info_for_irq(irq);
if (WARN_ON(!info))
return;
@@ -1148,7 +1161,7 @@ int evtchn_make_refcounted(unsigned int
if (irq == -1)
return -ENOENT;
- info = irq_get_chip_data(irq);
+ info = info_for_irq(irq);
if (!info)
return -ENOENT;
@@ -1176,7 +1189,7 @@ int evtchn_get(unsigned int evtchn)
if (irq == -1)
goto done;
- info = irq_get_chip_data(irq);
+ info = info_for_irq(irq);
if (!info)
goto done;
