Re: [PATCH v4 23/25] arm: vgic emulation

[David Vrabel <david.vrabel@citrix.com>]

On 09/01/12 17:59, stefano.stabellini@eu.citrix.com wrote:
> 
> +static int vgic_distr_mmio_read(struct vcpu *v, mmio_info_t *info)
> +{
[...]
> +    case GICD_ICFGR ... GICD_ICFGRN:
> +        if ( dabt.size != 2 ) goto bad_width;
> +        rank = vgic_irq_rank(v, 2, gicd_reg - GICD_ICFGR);
> +        if ( rank == NULL) goto read_as_zero;
> +        vgic_lock_rank(v, rank);
> +        *r = rank->icfg[REG_RANK_INDEX(2, gicd_reg - GICD_ICFGR)];
> +        vgic_unlock_rank(v, rank);
> +        return 0;

This needs to return 1 or recent kernels will crash when they try and
read these registers.

David

>From 8c2377a9b4a10cba57fba9f8a19177ac73339d78 Mon Sep 17 00:00:00 2001
From: David Vrabel <david.vrabel@citrix.com>
Date: Mon, 9 Jan 2012 15:17:22 +0000
Subject: [PATCH] ARM: allow guest to read GICD_ICFGRn registers

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
---
 xen/arch/arm/vgic.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index 26eae55..584e682 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -266,7 +266,7 @@ static int vgic_distr_mmio_read(struct vcpu *v,
mmio_info_t *info)
         vgic_lock_rank(v, rank);
         *r = rank->icfg[REG_RANK_INDEX(2, gicd_reg - GICD_ICFGR)];
         vgic_unlock_rank(v, rank);
-        return 0;
+        return 1;

     case GICD_NSACR ... GICD_NSACRN:
         /* We do not implement securty extensions for guests, read zero */