[PATCH v2 12/15] xen/arm: vgic-v2: Take the lock when writing into GICD_CTLR

[Julien Grall <julien.grall@linaro.org>]

This register is shared between every vCPUs and the lock was already
taken for read.

Signed-off-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

---
    This patch should be backported to Xen 4.4 and Xen 4.5.

    Although, it won't apply directly for Xen 4.4.

    Changes in v2:
        - Add Ian's ack
---
 xen/arch/arm/vgic-v2.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/xen/arch/arm/vgic-v2.c b/xen/arch/arm/vgic-v2.c
index 6530ecc..e7cdf9e 100644
--- a/xen/arch/arm/vgic-v2.c
+++ b/xen/arch/arm/vgic-v2.c
@@ -281,7 +281,10 @@ static int vgic_v2_distr_mmio_write(struct vcpu *v, mmio_info_t *info)
     case GICD_CTLR:
         if ( dabt.size != DABT_WORD ) goto bad_width;
         /* Ignore all but the enable bit */
+        vgic_lock(v);
         v->domain->arch.vgic.ctlr = (*r) & GICD_CTL_ENABLE;
+        vgic_unlock(v);
+
         return 1;
 
     /* R/O -- write ignored */
-- 
2.1.4