File 25836-VT-d-S3-MSI-resume.patch of Package xen.openSUSE_12.1_Update

# HG changeset patch
# User Jan Beulich <jbeulich@suse.com>
# Date 1347263130 -7200
# Node ID 7d216f026f71022186196a75244e97cf3864f50b
# Parent  c70d70d85306b3e4a0538353be131100c5ee38d5
VT-d: split .ack and .disable DMA-MSI actors

Calling irq_complete_move() from .disable is wrong, breaking S3 resume.

Comparing with all other .ack actors, it was also missing a call to
move_{native,masked}_irq(). As the actor is masking its interrupt
anyway (albeit it's not immediately obvious why), the latter is the
better choice.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
Acked-by Xiantao Zhang <xiantao.zhang@intel.com>

--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -1011,9 +1011,6 @@ static void dma_msi_mask(unsigned int ir
 {
     unsigned long flags;
     struct iommu *iommu = irq_to_iommu[irq];
-    struct irq_desc *desc = irq_to_desc(irq);
-
-    irq_complete_move(&desc);
 
     /* mask it */
     spin_lock_irqsave(&iommu->register_lock, flags);
@@ -1027,6 +1024,15 @@ static unsigned int dma_msi_startup(unsi
     return 0;
 }
 
+static void dma_msi_ack(unsigned int irq)
+{
+    struct irq_desc *desc = irq_to_desc(irq);
+
+    irq_complete_move(&desc);
+    dma_msi_mask(irq);
+    move_masked_irq(irq);
+}
+
 static void dma_msi_end(unsigned int irq, u8 vector)
 {
     dma_msi_unmask(irq);
@@ -1091,7 +1097,7 @@ static hw_irq_controller dma_msi_type = 
     .shutdown = dma_msi_mask,
     .enable = dma_msi_unmask,
     .disable = dma_msi_mask,
-    .ack = dma_msi_mask,
+    .ack = dma_msi_ack,
     .end = dma_msi_end,
     .set_affinity = dma_msi_set_affinity,
 };