diff options
| author | Juergen Gross <jgross@suse.com> | 2024-03-13 10:14:09 +0300 |
|---|---|---|
| committer | Juergen Gross <jgross@suse.com> | 2024-03-17 20:57:12 +0300 |
| commit | d277f9d82802223f242cd9b60c988cfdda1d6be0 (patch) | |
| tree | 84e04e64e8dd68f71e65dc4d15d472d1d3cd7c80 | |
| parent | 51c23bd691c0f1fb95b29731c356c6fd69925d17 (diff) | |
| download | linux-d277f9d82802223f242cd9b60c988cfdda1d6be0.tar.xz | |
xen/events: increment refcnt only if event channel is refcounted
In bind_evtchn_to_irq_chip() don't increment the refcnt of the event
channel blindly. In case the event channel is NOT refcounted, issue a
warning instead.
Add an additional safety net by doing the refcnt increment only if the
caller has specified IRQF_SHARED in the irqflags parameter.
Fixes: 9e90e58c11b7 ("xen: evtchn: Allow shared registration of IRQ handers")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Link: https://lore.kernel.org/r/20240313071409.25913-3-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
| -rw-r--r-- | drivers/xen/events/events_base.c | 22 |
1 files changed, 13 insertions, 9 deletions
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 3b9f080109d7..27553673e46b 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -1190,7 +1190,7 @@ int xen_pirq_from_irq(unsigned irq) EXPORT_SYMBOL_GPL(xen_pirq_from_irq); static int bind_evtchn_to_irq_chip(evtchn_port_t evtchn, struct irq_chip *chip, - struct xenbus_device *dev) + struct xenbus_device *dev, bool shared) { int ret = -ENOMEM; struct irq_info *info; @@ -1224,7 +1224,8 @@ static int bind_evtchn_to_irq_chip(evtchn_port_t evtchn, struct irq_chip *chip, */ bind_evtchn_to_cpu(info, 0, false); } else if (!WARN_ON(info->type != IRQT_EVTCHN)) { - info->refcnt++; + if (shared && !WARN_ON(info->refcnt < 0)) + info->refcnt++; } ret = info->irq; @@ -1237,13 +1238,13 @@ out: int bind_evtchn_to_irq(evtchn_port_t evtchn) { - return bind_evtchn_to_irq_chip(evtchn, &xen_dynamic_chip, NULL); + return bind_evtchn_to_irq_chip(evtchn, &xen_dynamic_chip, NULL, false); } EXPORT_SYMBOL_GPL(bind_evtchn_to_irq); int bind_evtchn_to_irq_lateeoi(evtchn_port_t evtchn) { - return bind_evtchn_to_irq_chip(evtchn, &xen_lateeoi_chip, NULL); + return bind_evtchn_to_irq_chip(evtchn, &xen_lateeoi_chip, NULL, false); } EXPORT_SYMBOL_GPL(bind_evtchn_to_irq_lateeoi); @@ -1295,7 +1296,8 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) static int bind_interdomain_evtchn_to_irq_chip(struct xenbus_device *dev, evtchn_port_t remote_port, - struct irq_chip *chip) + struct irq_chip *chip, + bool shared) { struct evtchn_bind_interdomain bind_interdomain; int err; @@ -1307,14 +1309,14 @@ static int bind_interdomain_evtchn_to_irq_chip(struct xenbus_device *dev, &bind_interdomain); return err ? : bind_evtchn_to_irq_chip(bind_interdomain.local_port, - chip, dev); + chip, dev, shared); } int bind_interdomain_evtchn_to_irq_lateeoi(struct xenbus_device *dev, evtchn_port_t remote_port) { return bind_interdomain_evtchn_to_irq_chip(dev, remote_port, - &xen_lateeoi_chip); + &xen_lateeoi_chip, false); } EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irq_lateeoi); @@ -1430,7 +1432,8 @@ static int bind_evtchn_to_irqhandler_chip(evtchn_port_t evtchn, { int irq, retval; - irq = bind_evtchn_to_irq_chip(evtchn, chip, NULL); + irq = bind_evtchn_to_irq_chip(evtchn, chip, NULL, + irqflags & IRQF_SHARED); if (irq < 0) return irq; retval = request_irq(irq, handler, irqflags, devname, dev_id); @@ -1471,7 +1474,8 @@ static int bind_interdomain_evtchn_to_irqhandler_chip( { int irq, retval; - irq = bind_interdomain_evtchn_to_irq_chip(dev, remote_port, chip); + irq = bind_interdomain_evtchn_to_irq_chip(dev, remote_port, chip, + irqflags & IRQF_SHARED); if (irq < 0) return irq; |