diff options
| author |   Juergen Gross <jgross@suse.com> | 2021-02-19 16:40:29 +0100 |
|---|---|---|
| committer |   Boris Ostrovsky <boris.ostrovsky@oracle.com> | 2021-02-23 10:07:43 -0600 |
| commit | d56699594046d54f32936a1eec337a62c15f931a (patch) | |
| tree | 6e9f33c0b10c24116a31dfeab1e1ee9b64de1bfc | |
| parent | xen/events: add per-xenbus device event statistics and settings (diff) | |
| download | linux-dev-d56699594046d54f32936a1eec337a62c15f931a.tar.xz linux-dev-d56699594046d54f32936a1eec337a62c15f931a.zip | |
xen/evtchn: use smp barriers for user event ring
The ring buffer for user events is local to the given kernel instance,
so smp barriers are fine for ensuring consistency.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Link: https://lore.kernel.org/r/20210219154030.10892-8-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
| -rw-r--r-- | drivers/xen/evtchn.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c index a7a85719a8c8..421382c73d88 100644 --- a/drivers/xen/evtchn.c +++ b/drivers/xen/evtchn.c @@ -173,7 +173,7 @@ static irqreturn_t evtchn_interrupt(int irq, void *data) if ((u->ring_prod - u->ring_cons) < u->ring_size) { *evtchn_ring_entry(u, u->ring_prod) = evtchn->port; - wmb(); /* Ensure ring contents visible */ + smp_wmb(); /* Ensure ring contents visible */ if (u->ring_cons == u->ring_prod++) { wake_up_interruptible(&u->evtchn_wait); kill_fasync(&u->evtchn_async_queue, @@ -245,7 +245,7 @@ static ssize_t evtchn_read(struct file *file, char __user *buf, } rc = -EFAULT; - rmb(); /* Ensure that we see the port before we copy it. */ + smp_rmb(); /* Ensure that we see the port before we copy it. */ if (copy_to_user(buf, evtchn_ring_entry(u, c), bytes1) || ((bytes2 != 0) && copy_to_user(&buf[bytes1], &u->ring[0], bytes2))) |