thr3ads.net - Xen devel - [PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC [Jun 2012]

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Stefano Stabellini

2012-Jun-06 11:20 UTC

[PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC

Hi all,
this patch series fixes the GIC, VGIC and vtimer issues that caused dom1
to hang, as described by Ian in
http://marc.info/?l=xen-devel&m=133856539418794.

With this patch series applied on top of Ian''s, dom1 boots up to:

VFS: Cannot open root device "(null)" or unknown-block(2,0)


Stefano Stabellini (5):
      arm/vtimer: do not let the guest interact with the physical timer
      arm/gic: fix gic context switch
      xen/gic: support injecting IRQs even to VCPUs not currently running
      xen/vgic: vgic: support irq enable/disable
      xen/vgic: initialize pending_irqs.lr_queue

 xen/arch/arm/gic.c           |   76 +++++++++++++++++++++++++++++++-----------
 xen/arch/arm/gic.h           |    2 +-
 xen/arch/arm/time.c          |    4 +-
 xen/arch/arm/vgic.c          |   30 ++++++++++++++++-
 xen/include/asm-arm/domain.h |    9 +++++
 5 files changed, 97 insertions(+), 24 deletions(-)

Cheers,

Stefano

Stefano Stabellini

2012-Jun-06 11:22 UTC

head link

[PATCH 1/5] arm/vtimer: do not let the guest interact with the physical timer

The guest can read the physical counter but it shouldn''t be able to
cause interrupts of the physical timer to go to the hypervisor.
Trap physical timer reads/writes in vtimer.c instead.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 xen/arch/arm/time.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
index 1587fa2..d5b71d7 100644
--- a/xen/arch/arm/time.c
+++ b/xen/arch/arm/time.c
@@ -160,8 +160,8 @@ void __cpuinit init_timer_interrupt(void)
     WRITE_CP64(0, CNTVOFF);     /* No VM-specific offset */
     WRITE_CP32(0, CNTKCTL);     /* No user-mode access */
 #if USE_HYP_TIMER
-    /* Let the VMs read the physical counter and timer so they can tell time */
-    WRITE_CP32(CNTHCTL_PA|CNTHCTL_TA, CNTHCTL);
+    /* Do not the VMs program the physical timer, only read the physical
counter */
+    WRITE_CP32(CNTHCTL_PA, CNTHCTL);
 #else
     /* Cannot let VMs access physical counter if we are using it */
     WRITE_CP32(0, CNTHCTL);
-- 
1.7.2.5

Stefano Stabellini

2012-Jun-06 11:22 UTC

head link

[PATCH 2/5] arm/gic: fix gic context switch

gic_save/restore_state should also save and restore lr_mask and
event_mask too.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 xen/arch/arm/gic.c           |    4 ++++
 xen/include/asm-arm/domain.h |    2 ++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index 3f9a061..c73f274 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -67,6 +67,8 @@ void gic_save_state(struct vcpu *v)
 
     for ( i=0; i<nr_lrs; i++)
         v->arch.gic_lr[i] = GICH[GICH_LR + i];
+    v->arch.lr_mask = gic.lr_mask;
+    v->arch.event_mask = gic.event_mask;
     /* Disable until next VCPU scheduled */
     GICH[GICH_HCR] = 0;
     isb();
@@ -79,6 +81,8 @@ void gic_restore_state(struct vcpu *v)
     if ( is_idle_vcpu(v) )
         return;
 
+    gic.lr_mask = v->arch.lr_mask;
+    gic.event_mask = v->arch.event_mask;
     for ( i=0; i<nr_lrs; i++)
         GICH[GICH_LR + i] = v->arch.gic_lr[i];
     GICH[GICH_HCR] = GICH_HCR_EN;
diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
index 230ea8c..3576d50 100644
--- a/xen/include/asm-arm/domain.h
+++ b/xen/include/asm-arm/domain.h
@@ -121,6 +121,8 @@ struct arch_vcpu
 
     uint32_t gic_hcr, gic_vmcr, gic_apr;
     uint32_t gic_lr[64];
+    uint64_t event_mask;
+    uint64_t lr_mask;
 
     struct {
         /*
-- 
1.7.2.5

Stefano Stabellini

2012-Jun-06 11:22 UTC

head link

[PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

The lr_pending list belongs to the vgic rather than the gic, so move it
there.

gic_set_guest_irq should take into account whether the vcpu is currently
running and if it is not it should add the irq to the right lr_pending
list.

When restoring the gic state we need to go through the lr_pending list
because it is possible that some irqs have been "injected" while the
vcpu wasn''t running.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 xen/arch/arm/gic.c           |   66 +++++++++++++++++++++++++++++------------
 xen/arch/arm/gic.h           |    2 +-
 xen/arch/arm/vgic.c          |    3 +-
 xen/include/asm-arm/domain.h |    7 ++++
 4 files changed, 56 insertions(+), 22 deletions(-)

diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index c73f274..2e41d75 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -38,6 +38,7 @@
 #define GICH ((volatile uint32_t *) (FIXMAP_ADDR(FIXMAP_GICH)  \
                                      + (GIC_HR_OFFSET & 0xfff)))
 static void events_maintenance(struct vcpu *v);
+static void gic_restore_pending_irqs(struct vcpu *v);
 
 /* Global state */
 static struct {
@@ -49,13 +50,6 @@ static struct {
     spinlock_t lock;
     uint64_t event_mask;
     uint64_t lr_mask;
-    /* lr_pending is used to queue IRQs (struct pending_irq) that the
-     * vgic tried to inject in the guest (calling gic_set_guest_irq) but
-     * no LRs were available at the time.
-     * As soon as an LR is freed we remove the first IRQ from this
-     * list and write it to the LR register.
-     * lr_pending is a subset of vgic.inflight_irqs. */
-    struct list_head lr_pending;
 } gic;
 
 irq_desc_t irq_desc[NR_IRQS];
@@ -87,6 +81,8 @@ void gic_restore_state(struct vcpu *v)
         GICH[GICH_LR + i] = v->arch.gic_lr[i];
     GICH[GICH_HCR] = GICH_HCR_EN;
     isb();
+
+    gic_restore_pending_irqs(v);
 }
 
 static unsigned int gic_irq_startup(struct irq_desc *desc)
@@ -323,7 +319,6 @@ int __init gic_init(void)
 
     gic.lr_mask = 0ULL;
     gic.event_mask = 0ULL;
-    INIT_LIST_HEAD(&gic.lr_pending);
 
     spin_unlock(&gic.lock);
 
@@ -435,17 +430,20 @@ static inline void gic_set_lr(int lr, unsigned int
virtual_irq,
         ((virtual_irq & GICH_LR_VIRTUAL_MASK) <<
GICH_LR_VIRTUAL_SHIFT);
 }
 
-void gic_set_guest_irq(unsigned int virtual_irq,
+void gic_set_guest_irq(struct vcpu *v, unsigned int virtual_irq,
         unsigned int state, unsigned int priority)
 {
     int i;
     struct pending_irq *iter, *n;
 
-    events_maintenance(current);
+    if ( v->is_running )
+    {
+        events_maintenance(v);
+    }
 
     spin_lock_irq(&gic.lock);
 
-    if ( list_empty(&gic.lr_pending) )
+    if ( v->is_running &&
list_empty(&v->arch.vgic.lr_pending) )
     {
         i = find_first_zero_bit(&gic.lr_mask, nr_lrs);
         if (i < nr_lrs) {
@@ -457,8 +455,8 @@ void gic_set_guest_irq(unsigned int virtual_irq,
         }
     }
 
-    n = irq_to_pending(current, virtual_irq);
-    list_for_each_entry ( iter, &gic.lr_pending, lr_queue )
+    n = irq_to_pending(v, virtual_irq);
+    list_for_each_entry ( iter, &v->arch.vgic.lr_pending, lr_queue )
     {
         if ( iter->priority > priority )
         {
@@ -466,13 +464,40 @@ void gic_set_guest_irq(unsigned int virtual_irq,
             goto out;
         }
     }
-    list_add_tail(&n->lr_queue, &gic.lr_pending);
+    list_add_tail(&n->lr_queue, &v->arch.vgic.lr_pending);
 
 out:
     spin_unlock_irq(&gic.lock);
     return;
 }
 
+static void gic_restore_pending_irqs(struct vcpu *v)
+{
+    int i;
+    struct pending_irq *p;
+
+    /* check for new pending irqs */
+    if ( list_empty(&v->arch.vgic.lr_pending) )
+        return;
+
+    list_for_each_entry ( p, &v->arch.vgic.lr_pending, lr_queue )
+    {
+        i = find_first_zero_bit(&gic.lr_mask, nr_lrs);
+        if ( i < nr_lrs )
+        {
+            gic_set_lr(i, p->irq, GICH_LR_PENDING, p->priority);
+            list_del_init(&p->lr_queue);
+            set_bit(i, &gic.lr_mask);
+            if ( p->irq == VGIC_IRQ_EVTCHN_CALLBACK )
+                set_bit(i, &gic.event_mask);
+        } else
+        {
+            return;
+        }
+    }
+
+}
+
 static void gic_inject_irq_start(void)
 {
     uint32_t hcr;
@@ -582,9 +607,10 @@ static void maintenance_interrupt(int irq, void *dev_id,
struct cpu_user_regs *r
 {
     int i = 0, virq;
     uint32_t lr;
+    struct vcpu *v = current;
     uint64_t eisr = GICH[GICH_EISR0] | (((uint64_t) GICH[GICH_EISR1]) <<
32);
 
-    events_maintenance(current);
+    events_maintenance(v);
 
     while ((i = find_next_bit((const long unsigned int *) &eisr,
                               sizeof(eisr), i)) < sizeof(eisr)) {
@@ -596,8 +622,8 @@ static void maintenance_interrupt(int irq, void *dev_id,
struct cpu_user_regs *r
         GICH[GICH_LR + i] = 0;
         clear_bit(i, &gic.lr_mask);
 
-        if ( !list_empty(&gic.lr_pending) ) {
-            p = list_entry(gic.lr_pending.next, typeof(*p), lr_queue);
+        if ( !list_empty(&v->arch.vgic.lr_pending) ) {
+            p = list_entry(v->arch.vgic.lr_pending.next, typeof(*p),
lr_queue);
             gic_set_lr(i, p->irq, GICH_LR_PENDING, p->priority);
             list_del_init(&p->lr_queue);
             set_bit(i, &gic.lr_mask);
@@ -608,14 +634,14 @@ static void maintenance_interrupt(int irq, void *dev_id,
struct cpu_user_regs *r
         }
         spin_unlock_irq(&gic.lock);
 
-        spin_lock(&current->arch.vgic.lock);
-        p = irq_to_pending(current, virq);
+        spin_lock(&v->arch.vgic.lock);
+        p = irq_to_pending(v, virq);
         if ( p->desc != NULL ) {
             p->desc->status &= ~IRQ_INPROGRESS;
             GICC[GICC_DIR] = virq;
         }
         list_del_init(&p->inflight);
-        spin_unlock(&current->arch.vgic.lock);
+        spin_unlock(&v->arch.vgic.lock);
 
         i++;
     }
diff --git a/xen/arch/arm/gic.h b/xen/arch/arm/gic.h
index ac9cf3a..a55e146 100644
--- a/xen/arch/arm/gic.h
+++ b/xen/arch/arm/gic.h
@@ -134,7 +134,7 @@ extern void gic_route_irqs(void);
 extern void gic_inject(void);
 
 extern void __cpuinit init_maintenance_interrupt(void);
-extern void gic_set_guest_irq(unsigned int irq,
+extern void gic_set_guest_irq(struct vcpu *v, unsigned int irq,
         unsigned int state, unsigned int priority);
 extern int gic_route_irq_to_guest(struct domain *d, unsigned int irq,
                                   const char * devname);
diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index 6eb6ec7..5a624bd 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -112,6 +112,7 @@ int vcpu_vgic_init(struct vcpu *v)
             | (1<<(v->vcpu_id+16))
             | (1<<(v->vcpu_id+24));
     INIT_LIST_HEAD(&v->arch.vgic.inflight_irqs);
+    INIT_LIST_HEAD(&v->arch.vgic.lr_pending);
     spin_lock_init(&v->arch.vgic.lock);
 
     return 0;
@@ -568,7 +569,7 @@ void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int irq,
int virtual)
     else
         n->desc = NULL;
 
-    gic_set_guest_irq(irq, GICH_LR_PENDING, priority);
+    gic_set_guest_irq(v, irq, GICH_LR_PENDING, priority);
 
     spin_lock_irqsave(&v->arch.vgic.lock, flags);
     list_for_each_entry ( iter, &v->arch.vgic.inflight_irqs, inflight )
diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
index 3576d50..2b14545 100644
--- a/xen/include/asm-arm/domain.h
+++ b/xen/include/asm-arm/domain.h
@@ -140,6 +140,13 @@ struct arch_vcpu
          * As soon as an IRQ is EOI''d by the guest and removed from
the
          * corresponding LR it is also removed from this list. */
         struct list_head inflight_irqs;
+        /* lr_pending is used to queue IRQs (struct pending_irq) that the
+         * vgic tried to inject in the guest (calling gic_set_guest_irq) but
+         * no LRs were available at the time.
+         * As soon as an LR is freed we remove the first IRQ from this
+         * list and write it to the LR register.
+         * lr_pending is a subset of vgic.inflight_irqs. */
+        struct list_head lr_pending;
         spinlock_t lock;
     } vgic;
 
-- 
1.7.2.5

Stefano Stabellini

2012-Jun-06 11:22 UTC

head link

[PATCH 4/5] xen/vgic: vgic: support irq enable/disable

If vgic_vcpu_inject_irq is called (for example by a device emulator like
vtimer.c) but the corresponding irq is not enabled in the virtual gicd
just queue it in the inflight_irqs list.

When the irq is enabled make sure to call gic_set_guest_irq.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 xen/arch/arm/vgic.c |   23 ++++++++++++++++++++++-
 1 files changed, 22 insertions(+), 1 deletions(-)

diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index 5a624bd..4cdfec5 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -343,6 +343,22 @@ read_as_zero:
     return 1;
 }
 
+static void vgic_enable_irqs(struct vcpu *v, uint32_t r, int n)
+{
+    struct pending_irq *p;
+    unsigned int irq;
+    int i = 0;
+
+    while ( (i = find_next_bit((const long unsigned int *) &r,
+                        sizeof(uint32_t), i)) < sizeof(uint32_t) ) {
+        irq = i + (32 * n);
+        p = irq_to_pending(v, irq);
+        if ( !list_empty(&p->inflight) )
+            gic_set_guest_irq(v, irq, GICH_LR_PENDING, p->priority);
+        i++;
+    }
+}
+
 static int vgic_distr_mmio_write(struct vcpu *v, mmio_info_t *info)
 {
     struct hsr_dabt dabt = info->dabt;
@@ -351,6 +367,7 @@ static int vgic_distr_mmio_write(struct vcpu *v, mmio_info_t
*info)
     struct vgic_irq_rank *rank;
     int offset = (int)(info->gpa - VGIC_DISTR_BASE_ADDRESS);
     int gicd_reg = REG(offset);
+    uint32_t tr;
 
     switch ( gicd_reg )
     {
@@ -378,8 +395,10 @@ static int vgic_distr_mmio_write(struct vcpu *v,
mmio_info_t *info)
         rank = vgic_irq_rank(v, 8, gicd_reg - GICD_ISENABLER);
         if ( rank == NULL) goto write_ignore;
         vgic_lock_rank(v, rank);
+        tr = rank->ienable;
         rank->ienable |= *r;
         vgic_unlock_rank(v, rank);
+        vgic_enable_irqs(v, (*r) & (~tr), gicd_reg - GICD_ISENABLER);
         return 1;
 
     case GICD_ICENABLER ... GICD_ICENABLERN:
@@ -569,7 +588,9 @@ void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int irq,
int virtual)
     else
         n->desc = NULL;
 
-    gic_set_guest_irq(v, irq, GICH_LR_PENDING, priority);
+    /* the irq is enabled */
+    if ( rank->ienable & (1 << (irq % 32)) )
+        gic_set_guest_irq(v, irq, GICH_LR_PENDING, priority);
 
     spin_lock_irqsave(&v->arch.vgic.lock, flags);
     list_for_each_entry ( iter, &v->arch.vgic.inflight_irqs, inflight )
-- 
1.7.2.5

Stefano Stabellini

2012-Jun-06 11:22 UTC

head link

[PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

Properly initialize all the pending_irqs.lr_queue like we do for
inflight.
Check whether we already have the irq in lr_queue before adding it.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 xen/arch/arm/gic.c  |    6 ++++++
 xen/arch/arm/vgic.c |    6 ++++++
 2 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index 2e41d75..998033a 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -456,6 +456,12 @@ void gic_set_guest_irq(struct vcpu *v, unsigned int
virtual_irq,
     }
 
     n = irq_to_pending(v, virtual_irq);
+    if ( !list_empty(&n->lr_queue) )
+    {
+        printk(KERN_WARNING "%s: irq %d already in lr_queue\n",
__func__,
+                virtual_irq);
+        goto out;
+    }
     list_for_each_entry ( iter, &v->arch.vgic.lr_pending, lr_queue )
     {
         if ( iter->priority > priority )
diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index 4cdfec5..653e8e5 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -84,7 +84,10 @@ int domain_vgic_init(struct domain *d)
     d->arch.vgic.pending_irqs          xzalloc_array(struct pending_irq,
d->arch.vgic.nr_lines);
     for (i=0; i<d->arch.vgic.nr_lines; i++)
+    {
         INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].inflight);
+        INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].lr_queue);
+    }
     for (i=0; i<DOMAIN_NR_RANKS(d); i++)
         spin_lock_init(&d->arch.vgic.shared_irqs[i].lock);
     return 0;
@@ -99,7 +102,10 @@ int vcpu_vgic_init(struct vcpu *v)
 
     memset(&v->arch.vgic.pending_irqs, 0,
sizeof(v->arch.vgic.pending_irqs));
     for (i = 0; i < 32; i++)
+    {
         INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].inflight);
+        INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].lr_queue);
+    }
     printk("vcpu_vgic_init irq[0] at %p desc is %p\n",
            &v->arch.vgic.pending_irqs[0],
            v->arch.vgic.pending_irqs[0].desc);
-- 
1.7.2.5

Tim Deegan

2012-Jun-07 12:46 UTC

head link

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

At 12:22 +0100 on 06 Jun (1338985328), Stefano Stabellini
wrote:> +static void gic_restore_pending_irqs(struct vcpu *v)
> +{
> +    int i;
> +    struct pending_irq *p;
> +
> +    /* check for new pending irqs */
> +    if ( list_empty(&v->arch.vgic.lr_pending) )
> +        return;
> +
> +    list_for_each_entry ( p, &v->arch.vgic.lr_pending, lr_queue )
> +    {
> +        i = find_first_zero_bit(&gic.lr_mask, nr_lrs);
> +        if ( i < nr_lrs )
> +        {
> +            gic_set_lr(i, p->irq, GICH_LR_PENDING, p->priority);
> +            list_del_init(&p->lr_queue);
> +            set_bit(i, &gic.lr_mask);
> +            if ( p->irq == VGIC_IRQ_EVTCHN_CALLBACK )
> +                set_bit(i, &gic.event_mask);
> +        } else
> +        {
> +            return;
> +        }
This is a bit ugly - maybe "if ( i >= nr_lrs ) return" above and
don''t
indent the block?

Tim Deegan

2012-Jun-07 12:47 UTC

head link

Re: [PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC

At 12:20 +0100 on 06 Jun (1338985240), Stefano Stabellini
wrote:> Hi all,
> this patch series fixes the GIC, VGIC and vtimer issues that caused dom1
> to hang, as described by Ian in
> http://marc.info/?l=xen-devel&m=133856539418794.
> 
> With this patch series applied on top of Ian''s, dom1 boots up to:
> 
> VFS: Cannot open root device "(null)" or unknown-block(2,0)
> 
I had one style nit on patch 3; you can add my Ack to all the others
(though IanC has a better grasp of the vgic stuff than I do and may
contradict me).

Cheers,

Tim.

Stefano Stabellini

2012-Jun-07 15:43 UTC

head link

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

On Thu, 7 Jun 2012, Tim Deegan wrote:> At 12:22 +0100 on 06 Jun (1338985328), Stefano Stabellini wrote:
> > +static void gic_restore_pending_irqs(struct vcpu *v)
> > +{
> > +    int i;
> > +    struct pending_irq *p;
> > +
> > +    /* check for new pending irqs */
> > +    if ( list_empty(&v->arch.vgic.lr_pending) )
> > +        return;
> > +
> > +    list_for_each_entry ( p, &v->arch.vgic.lr_pending,
lr_queue )
> > +    {
> > +        i = find_first_zero_bit(&gic.lr_mask, nr_lrs);
> > +        if ( i < nr_lrs )
> > +        {
> > +            gic_set_lr(i, p->irq, GICH_LR_PENDING,
p->priority);
> > +            list_del_init(&p->lr_queue);
> > +            set_bit(i, &gic.lr_mask);
> > +            if ( p->irq == VGIC_IRQ_EVTCHN_CALLBACK )
> > +                set_bit(i, &gic.event_mask);
> > +        } else
> > +        {
> > +            return;
> > +        }
> 
> This is a bit ugly - maybe "if ( i >= nr_lrs ) return" above
and don''t
> indent the block?
> 
good idea

Stefano Stabellini

2012-Jun-07 15:47 UTC

head link

Re: [PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC

On Thu, 7 Jun 2012, Tim Deegan wrote:> At 12:20 +0100 on 06 Jun (1338985240), Stefano Stabellini wrote:
> > Hi all,
> > this patch series fixes the GIC, VGIC and vtimer issues that caused
dom1
> > to hang, as described by Ian in
> > http://marc.info/?l=xen-devel&m=133856539418794.
> > 
> > With this patch series applied on top of Ian''s, dom1 boots up
to:
> > 
> > VFS: Cannot open root device "(null)" or unknown-block(2,0)
> > 
> 
> I had one style nit on patch 3; you can add my Ack to all the others
> (though IanC has a better grasp of the vgic stuff than I do and may
> contradict me).
great, thanks!

Ian Campbell

2012-Jun-26 13:55 UTC

head link

Re: [PATCH 1/5] arm/vtimer: do not let the guest interact with the physical timer

On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini
wrote:> The guest can read the physical counter but it shouldn''t be able
to
> cause interrupts of the physical timer to go to the hypervisor.
> Trap physical timer reads/writes in vtimer.c instead.
> 
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> ---
>  xen/arch/arm/time.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
> index 1587fa2..d5b71d7 100644
> --- a/xen/arch/arm/time.c
> +++ b/xen/arch/arm/time.c
> @@ -160,8 +160,8 @@ void __cpuinit init_timer_interrupt(void)
>      WRITE_CP64(0, CNTVOFF);     /* No VM-specific offset */
>      WRITE_CP32(0, CNTKCTL);     /* No user-mode access */
>  #if USE_HYP_TIMER
> -    /* Let the VMs read the physical counter and timer so they can tell
time */
> -    WRITE_CP32(CNTHCTL_PA|CNTHCTL_TA, CNTHCTL);
> +    /* Do not the VMs program the physical timer, only read the physical
counter */
"Do not *let* the VMs..." ?
> +    WRITE_CP32(CNTHCTL_PA, CNTHCTL);
>  #else
>      /* Cannot let VMs access physical counter if we are using it */
>      WRITE_CP32(0, CNTHCTL);

Ian Campbell

2012-Jun-26 13:55 UTC

head link

Re: [PATCH 2/5] arm/gic: fix gic context switch

On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini
wrote:> gic_save/restore_state should also save and restore lr_mask and
> event_mask too.
> 
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
> ---
>  xen/arch/arm/gic.c           |    4 ++++
>  xen/include/asm-arm/domain.h |    2 ++
>  2 files changed, 6 insertions(+), 0 deletions(-)
> 
> diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
> index 3f9a061..c73f274 100644
> --- a/xen/arch/arm/gic.c
> +++ b/xen/arch/arm/gic.c
> @@ -67,6 +67,8 @@ void gic_save_state(struct vcpu *v)
>  
>      for ( i=0; i<nr_lrs; i++)
>          v->arch.gic_lr[i] = GICH[GICH_LR + i];
> +    v->arch.lr_mask = gic.lr_mask;
> +    v->arch.event_mask = gic.event_mask;
>      /* Disable until next VCPU scheduled */
>      GICH[GICH_HCR] = 0;
>      isb();
> @@ -79,6 +81,8 @@ void gic_restore_state(struct vcpu *v)
>      if ( is_idle_vcpu(v) )
>          return;
>  
> +    gic.lr_mask = v->arch.lr_mask;
> +    gic.event_mask = v->arch.event_mask;
>      for ( i=0; i<nr_lrs; i++)
>          GICH[GICH_LR + i] = v->arch.gic_lr[i];
>      GICH[GICH_HCR] = GICH_HCR_EN;
> diff --git a/xen/include/asm-arm/domain.h b/xen/include/asm-arm/domain.h
> index 230ea8c..3576d50 100644
> --- a/xen/include/asm-arm/domain.h
> +++ b/xen/include/asm-arm/domain.h
> @@ -121,6 +121,8 @@ struct arch_vcpu
>  
>      uint32_t gic_hcr, gic_vmcr, gic_apr;
>      uint32_t gic_lr[64];
> +    uint64_t event_mask;
> +    uint64_t lr_mask;
>  
>      struct {
>          /*

Ian Campbell

2012-Jun-26 14:05 UTC

head link

Re: [PATCH 4/5] xen/vgic: vgic: support irq enable/disable

On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini
wrote:> If vgic_vcpu_inject_irq is called (for example by a device emulator like
> vtimer.c) but the corresponding irq is not enabled in the virtual gicd
> just queue it in the inflight_irqs list.
> When the irq is enabled make sure to call gic_set_guest_irq.
> 
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
I had to go reread the comments on inflight_irqs and lr_pending again
(I''m perpetually confused by that stuff) but I think this makes sense.

Acked-by: Ian Campbell <ian.campbell@citrix.com>
> ---
>  xen/arch/arm/vgic.c |   23 ++++++++++++++++++++++-
>  1 files changed, 22 insertions(+), 1 deletions(-)
> 
> diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
> index 5a624bd..4cdfec5 100644
> --- a/xen/arch/arm/vgic.c
> +++ b/xen/arch/arm/vgic.c
> @@ -343,6 +343,22 @@ read_as_zero:
>      return 1;
>  }
>  
> +static void vgic_enable_irqs(struct vcpu *v, uint32_t r, int n)
> +{
> +    struct pending_irq *p;
> +    unsigned int irq;
> +    int i = 0;
> +
> +    while ( (i = find_next_bit((const long unsigned int *) &r,
> +                        sizeof(uint32_t), i)) < sizeof(uint32_t) ) {
> +        irq = i + (32 * n);
> +        p = irq_to_pending(v, irq);
> +        if ( !list_empty(&p->inflight) )
> +            gic_set_guest_irq(v, irq, GICH_LR_PENDING, p->priority);
> +        i++;
what you have here is a for loop ;-)
> +    }
> +}
> +
>  static int vgic_distr_mmio_write(struct vcpu *v, mmio_info_t *info)
>  {
>      struct hsr_dabt dabt = info->dabt;
> @@ -351,6 +367,7 @@ static int vgic_distr_mmio_write(struct vcpu *v,
mmio_info_t *info)
>      struct vgic_irq_rank *rank;
>      int offset = (int)(info->gpa - VGIC_DISTR_BASE_ADDRESS);
>      int gicd_reg = REG(offset);
> +    uint32_t tr;
>  
>      switch ( gicd_reg )
>      {
> @@ -378,8 +395,10 @@ static int vgic_distr_mmio_write(struct vcpu *v,
mmio_info_t *info)
>          rank = vgic_irq_rank(v, 8, gicd_reg - GICD_ISENABLER);
>          if ( rank == NULL) goto write_ignore;
>          vgic_lock_rank(v, rank);
> +        tr = rank->ienable;
>          rank->ienable |= *r;
>          vgic_unlock_rank(v, rank);
> +        vgic_enable_irqs(v, (*r) & (~tr), gicd_reg - GICD_ISENABLER);
>          return 1;
>  
>      case GICD_ICENABLER ... GICD_ICENABLERN:
> @@ -569,7 +588,9 @@ void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int
irq, int virtual)
>      else
>          n->desc = NULL;
>  
> -    gic_set_guest_irq(v, irq, GICH_LR_PENDING, priority);
> +    /* the irq is enabled */
> +    if ( rank->ienable & (1 << (irq % 32)) )
> +        gic_set_guest_irq(v, irq, GICH_LR_PENDING, priority);
>  
>      spin_lock_irqsave(&v->arch.vgic.lock, flags);
>      list_for_each_entry ( iter, &v->arch.vgic.inflight_irqs,
inflight )

Ian Campbell

2012-Jun-26 14:07 UTC

head link

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

On Thu, 2012-06-07 at 13:46 +0100, Tim Deegan wrote:> At 12:22 +0100 on 06 Jun (1338985328), Stefano Stabellini wrote:
> > +static void gic_restore_pending_irqs(struct vcpu *v)
> > +{
> > +    int i;
> > +    struct pending_irq *p;
> > +
> > +    /* check for new pending irqs */
> > +    if ( list_empty(&v->arch.vgic.lr_pending) )
> > +        return;
> > +
> > +    list_for_each_entry ( p, &v->arch.vgic.lr_pending,
lr_queue )
Is list_for_each_entry on an empty list somehow wrong/buggy/slow?
> > +    {
> > +        i = find_first_zero_bit(&gic.lr_mask, nr_lrs);
> > +        if ( i < nr_lrs )
> > +        {
> > +            gic_set_lr(i, p->irq, GICH_LR_PENDING,
p->priority);
> > +            list_del_init(&p->lr_queue);
> > +            set_bit(i, &gic.lr_mask);
> > +            if ( p->irq == VGIC_IRQ_EVTCHN_CALLBACK )
> > +                set_bit(i, &gic.event_mask);
> > +        } else
> > +        {
> > +            return;
> > +        }
> 
> This is a bit ugly - maybe "if ( i >= nr_lrs ) return" above
and don''t
> indent the block?
>

Ian Campbell

2012-Jun-26 14:08 UTC

head link

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini
wrote:> Properly initialize all the pending_irqs.lr_queue like we do for
> inflight.
> Check whether we already have the irq in lr_queue before adding it.
Should this be a fatal error? Can a guest make this happen?
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> ---
>  xen/arch/arm/gic.c  |    6 ++++++
>  xen/arch/arm/vgic.c |    6 ++++++
>  2 files changed, 12 insertions(+), 0 deletions(-)
> 
> diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
> index 2e41d75..998033a 100644
> --- a/xen/arch/arm/gic.c
> +++ b/xen/arch/arm/gic.c
> @@ -456,6 +456,12 @@ void gic_set_guest_irq(struct vcpu *v, unsigned int
virtual_irq,
>      }
>  
>      n = irq_to_pending(v, virtual_irq);
> +    if ( !list_empty(&n->lr_queue) )
> +    {
> +        printk(KERN_WARNING "%s: irq %d already in lr_queue\n",
__func__,
> +                virtual_irq);
> +        goto out;
> +    }
>      list_for_each_entry ( iter, &v->arch.vgic.lr_pending, lr_queue
)
>      {
>          if ( iter->priority > priority )
> diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
> index 4cdfec5..653e8e5 100644
> --- a/xen/arch/arm/vgic.c
> +++ b/xen/arch/arm/vgic.c
> @@ -84,7 +84,10 @@ int domain_vgic_init(struct domain *d)
>      d->arch.vgic.pending_irqs >          xzalloc_array(struct
pending_irq, d->arch.vgic.nr_lines);
>      for (i=0; i<d->arch.vgic.nr_lines; i++)
> +    {
>          INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].inflight);
> +        INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].lr_queue);
> +    }
>      for (i=0; i<DOMAIN_NR_RANKS(d); i++)
>          spin_lock_init(&d->arch.vgic.shared_irqs[i].lock);
>      return 0;
> @@ -99,7 +102,10 @@ int vcpu_vgic_init(struct vcpu *v)
>  
>      memset(&v->arch.vgic.pending_irqs, 0,
sizeof(v->arch.vgic.pending_irqs));
>      for (i = 0; i < 32; i++)
> +    {
>          INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].inflight);
> +        INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].lr_queue);
> +    }
>      printk("vcpu_vgic_init irq[0] at %p desc is %p\n",
>             &v->arch.vgic.pending_irqs[0],
>             v->arch.vgic.pending_irqs[0].desc);

Stefano Stabellini

2012-Jun-26 17:25 UTC

head link

Re: [PATCH 1/5] arm/vtimer: do not let the guest interact with the physical timer

On Tue, 26 Jun 2012, Ian Campbell wrote:> On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini wrote:
> > The guest can read the physical counter but it shouldn''t be
able to
> > cause interrupts of the physical timer to go to the hypervisor.
> > Trap physical timer reads/writes in vtimer.c instead.
> > 
> > Signed-off-by: Stefano Stabellini
<stefano.stabellini@eu.citrix.com>
> > ---
> >  xen/arch/arm/time.c |    4 ++--
> >  1 files changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/xen/arch/arm/time.c b/xen/arch/arm/time.c
> > index 1587fa2..d5b71d7 100644
> > --- a/xen/arch/arm/time.c
> > +++ b/xen/arch/arm/time.c
> > @@ -160,8 +160,8 @@ void __cpuinit init_timer_interrupt(void)
> >      WRITE_CP64(0, CNTVOFF);     /* No VM-specific offset */
> >      WRITE_CP32(0, CNTKCTL);     /* No user-mode access */
> >  #if USE_HYP_TIMER
> > -    /* Let the VMs read the physical counter and timer so they can
tell time */
> > -    WRITE_CP32(CNTHCTL_PA|CNTHCTL_TA, CNTHCTL);
> > +    /* Do not the VMs program the physical timer, only read the
physical counter */
> 
> "Do not *let* the VMs..." ?
right..

Stefano Stabellini

2012-Jun-26 17:28 UTC

head link

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

On Tue, 26 Jun 2012, Ian Campbell wrote:> On Thu, 2012-06-07 at 13:46 +0100, Tim Deegan wrote:
> > At 12:22 +0100 on 06 Jun (1338985328), Stefano Stabellini wrote:
> > > +static void gic_restore_pending_irqs(struct vcpu *v)
> > > +{
> > > +    int i;
> > > +    struct pending_irq *p;
> > > +
> > > +    /* check for new pending irqs */
> > > +    if ( list_empty(&v->arch.vgic.lr_pending) )
> > > +        return;
> > > +
> > > +    list_for_each_entry ( p, &v->arch.vgic.lr_pending,
lr_queue )
> 
> Is list_for_each_entry on an empty list somehow wrong/buggy/slow?
Not at all. I''ll change it.

Stefano Stabellini

2012-Jun-26 17:53 UTC

head link

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

On Tue, 26 Jun 2012, Ian Campbell wrote:> On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini wrote:
> > Properly initialize all the pending_irqs.lr_queue like we do for
> > inflight.
> > Check whether we already have the irq in lr_queue before adding it.
> 
> Should this be a fatal error? Can a guest make this happen?
it could happen if the guest keeps enabling and disabling the irqs using
the GICD_ICENABLERn and the GICD_ISENABLERn registers.

> > Signed-off-by: Stefano Stabellini
<stefano.stabellini@eu.citrix.com>
> > ---
> >  xen/arch/arm/gic.c  |    6 ++++++
> >  xen/arch/arm/vgic.c |    6 ++++++
> >  2 files changed, 12 insertions(+), 0 deletions(-)
> > 
> > diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
> > index 2e41d75..998033a 100644
> > --- a/xen/arch/arm/gic.c
> > +++ b/xen/arch/arm/gic.c
> > @@ -456,6 +456,12 @@ void gic_set_guest_irq(struct vcpu *v, unsigned
int virtual_irq,
> >      }
> >  
> >      n = irq_to_pending(v, virtual_irq);
> > +    if ( !list_empty(&n->lr_queue) )
> > +    {
> > +        printk(KERN_WARNING "%s: irq %d already in
lr_queue\n", __func__,
> > +                virtual_irq);
> > +        goto out;
> > +    }
> >      list_for_each_entry ( iter, &v->arch.vgic.lr_pending,
lr_queue )
> >      {
> >          if ( iter->priority > priority )
> > diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
> > index 4cdfec5..653e8e5 100644
> > --- a/xen/arch/arm/vgic.c
> > +++ b/xen/arch/arm/vgic.c
> > @@ -84,7 +84,10 @@ int domain_vgic_init(struct domain *d)
> >      d->arch.vgic.pending_irqs > >         
xzalloc_array(struct pending_irq, d->arch.vgic.nr_lines);
> >      for (i=0; i<d->arch.vgic.nr_lines; i++)
> > +    {
> >         
INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].inflight);
> > +       
INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].lr_queue);
> > +    }
> >      for (i=0; i<DOMAIN_NR_RANKS(d); i++)
> >          spin_lock_init(&d->arch.vgic.shared_irqs[i].lock);
> >      return 0;
> > @@ -99,7 +102,10 @@ int vcpu_vgic_init(struct vcpu *v)
> >  
> >      memset(&v->arch.vgic.pending_irqs, 0,
sizeof(v->arch.vgic.pending_irqs));
> >      for (i = 0; i < 32; i++)
> > +    {
> >         
INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].inflight);
> > +       
INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].lr_queue);
> > +    }
> >      printk("vcpu_vgic_init irq[0] at %p desc is %p\n",
> >             &v->arch.vgic.pending_irqs[0],
> >             v->arch.vgic.pending_irqs[0].desc);
> 
> 
>

Ian Campbell

2012-Jun-27 08:52 UTC

head link

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

On Tue, 2012-06-26 at 18:53 +0100, Stefano Stabellini
wrote:> On Tue, 26 Jun 2012, Ian Campbell wrote:
> > On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini wrote:
> > > Properly initialize all the pending_irqs.lr_queue like we do for
> > > inflight.
> > > Check whether we already have the irq in lr_queue before adding
it.
> > 
> > Should this be a fatal error? Can a guest make this happen?
> 
> it could happen if the guest keeps enabling and disabling the irqs using
> the GICD_ICENABLERn and the GICD_ISENABLERn registers.
Then the printk is probably wrong. At the least it should be a gdprintk
but really I think it is unnecessary.
> 
> 
> > > Signed-off-by: Stefano Stabellini
<stefano.stabellini@eu.citrix.com>
> > > ---
> > >  xen/arch/arm/gic.c  |    6 ++++++
> > >  xen/arch/arm/vgic.c |    6 ++++++
> > >  2 files changed, 12 insertions(+), 0 deletions(-)
> > > 
> > > diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
> > > index 2e41d75..998033a 100644
> > > --- a/xen/arch/arm/gic.c
> > > +++ b/xen/arch/arm/gic.c
> > > @@ -456,6 +456,12 @@ void gic_set_guest_irq(struct vcpu *v,
unsigned int virtual_irq,
> > >      }
> > >  
> > >      n = irq_to_pending(v, virtual_irq);
> > > +    if ( !list_empty(&n->lr_queue) )
> > > +    {
> > > +        printk(KERN_WARNING "%s: irq %d already in
lr_queue\n", __func__,
> > > +                virtual_irq);
> > > +        goto out;
> > > +    }
> > >      list_for_each_entry ( iter, &v->arch.vgic.lr_pending,
lr_queue )
> > >      {
> > >          if ( iter->priority > priority )
> > > diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
> > > index 4cdfec5..653e8e5 100644
> > > --- a/xen/arch/arm/vgic.c
> > > +++ b/xen/arch/arm/vgic.c
> > > @@ -84,7 +84,10 @@ int domain_vgic_init(struct domain *d)
> > >      d->arch.vgic.pending_irqs > > >         
xzalloc_array(struct pending_irq, d->arch.vgic.nr_lines);
> > >      for (i=0; i<d->arch.vgic.nr_lines; i++)
> > > +    {
> > >         
INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].inflight);
> > > +       
INIT_LIST_HEAD(&d->arch.vgic.pending_irqs[i].lr_queue);
> > > +    }
> > >      for (i=0; i<DOMAIN_NR_RANKS(d); i++)
> > >         
spin_lock_init(&d->arch.vgic.shared_irqs[i].lock);
> > >      return 0;
> > > @@ -99,7 +102,10 @@ int vcpu_vgic_init(struct vcpu *v)
> > >  
> > >      memset(&v->arch.vgic.pending_irqs, 0,
sizeof(v->arch.vgic.pending_irqs));
> > >      for (i = 0; i < 32; i++)
> > > +    {
> > >         
INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].inflight);
> > > +       
INIT_LIST_HEAD(&v->arch.vgic.pending_irqs[i].lr_queue);
> > > +    }
> > >      printk("vcpu_vgic_init irq[0] at %p desc is %p\n",
> > >             &v->arch.vgic.pending_irqs[0],
> > >             v->arch.vgic.pending_irqs[0].desc);
> > 
> > 
> >

Stefano Stabellini

2012-Jun-27 11:06 UTC

head link

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

On Wed, 27 Jun 2012, Ian Campbell wrote:> On Tue, 2012-06-26 at 18:53 +0100, Stefano Stabellini wrote:
> > On Tue, 26 Jun 2012, Ian Campbell wrote:
> > > On Wed, 2012-06-06 at 12:22 +0100, Stefano Stabellini wrote:
> > > > Properly initialize all the pending_irqs.lr_queue like we do
for
> > > > inflight.
> > > > Check whether we already have the irq in lr_queue before
adding it.
> > > 
> > > Should this be a fatal error? Can a guest make this happen?
> > 
> > it could happen if the guest keeps enabling and disabling the irqs
using
> > the GICD_ICENABLERn and the GICD_ISENABLERn registers.
> 
> Then the printk is probably wrong. At the least it should be a gdprintk
> but really I think it is unnecessary.
OK, I''ll remove it.

Xen devel - Jun 2012 - [PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC

[PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC

[PATCH 1/5] arm/vtimer: do not let the guest interact with the physical timer

[PATCH 2/5] arm/gic: fix gic context switch

[PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

[PATCH 4/5] xen/vgic: vgic: support irq enable/disable

[PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

Re: [PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

Re: [PATCH 0/5] xen/arm: multiple guests support in the GIC and VGIC

Re: [PATCH 1/5] arm/vtimer: do not let the guest interact with the physical timer

Re: [PATCH 2/5] arm/gic: fix gic context switch

Re: [PATCH 4/5] xen/vgic: vgic: support irq enable/disable

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

Re: [PATCH 1/5] arm/vtimer: do not let the guest interact with the physical timer

Re: [PATCH 3/5] xen/gic: support injecting IRQs even to VCPUs not currently running

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue

Re: [PATCH 5/5] xen/vgic: initialize pending_irqs.lr_queue