Simon Horman wrote:
> In pt_irq_time_out() the following code loops through all used
> guest_gsi:
>
> list_for_each_entry ( digl, &irq_map->digl_list, list )
> {
> guest_gsi = digl->gsi;
> machine_gsi = dpci->girq[guest_gsi].machine_gsi;
> ...
> }
>
> And a little later on machine_gsi is used.
> That is the last machine_gsi found is used,
> rather than all of the machine_gsi that are found.
>
> This seems to be incorrect to me,
> but I am unsure of how to test this.
>
Timer is set for each machine GSI, so all the machine_gsi found in loop are the
same. More than one devices may share machine GSI, but assume they won't share
guest gsi. digl_list contains all guest GSIs which are correspond to this a
machine GSI.
Now you want pass-throughed devices share guest gsi, you needs to change it
obviously. Your below change looks fine for me.
Regards,
Weidong
> This code appears to have been introduced in
> "vt-d: Support intra-domain shared interrupt" by Weidong Han.
>
> Cc: Weidong Han <weidong.han@xxxxxxxxx>
> Cc: Yuji Shimada <shimada-yxb@xxxxxxxxxxxxxxx>
> Signed-off-by: Simon Horman <horms@xxxxxxxxxxxx>
>
> Index: xen-unstable.hg/xen/drivers/passthrough/io.c
> ===================================================================
> --- xen-unstable.hg.orig/xen/drivers/passthrough/io.c 2009-03-09
> 12:44:48.000000000 +1100 +++
> xen-unstable.hg/xen/drivers/passthrough/io.c 2009-03-09
> 12:58:28.000000000 +1100 @@ -37,6 +37,9 @@ static void
> pt_irq_time_out(void *data) struct hvm_irq_dpci *dpci = NULL;
> struct dev_intx_gsi_link *digl; uint32_t device, intx;
> + DECLARE_BITMAP(machine_gsi_map, NR_IRQS);
> +
> + bitmap_zero(machine_gsi_map, NR_IRQS);
>
> spin_lock(&irq_map->dom->event_lock);
>
> @@ -46,16 +49,31 @@ static void pt_irq_time_out(void *data)
> {
> guest_gsi = digl->gsi;
> machine_gsi = dpci->girq[guest_gsi].machine_gsi;
> + set_bit(machine_gsi, machine_gsi_map);
> device = digl->device;
> intx = digl->intx;
> hvm_pci_intx_deassert(irq_map->dom, device, intx);
> }
>
> - clear_bit(machine_gsi, dpci->dirq_mask);
> - vector = domain_irq_to_vector(irq_map->dom, machine_gsi);
> - dpci->mirq[machine_gsi].pending = 0;
> + for ( machine_gsi = find_first_bit(machine_gsi_map, NR_IRQS);
> + machine_gsi < NR_IRQS;
> + machine_gsi = find_next_bit(machine_gsi_map, NR_IRQS,
> + machine_gsi + 1) )
> + {
> + clear_bit(machine_gsi, dpci->dirq_mask);
> + vector = domain_irq_to_vector(irq_map->dom, machine_gsi);
> + dpci->mirq[machine_gsi].pending = 0;
> + }
> +
> spin_unlock(&irq_map->dom->event_lock);
> - pirq_guest_eoi(irq_map->dom, machine_gsi);
> +
> + for ( machine_gsi = find_first_bit(machine_gsi_map, NR_IRQS);
> + machine_gsi < NR_IRQS;
> + machine_gsi = find_next_bit(machine_gsi_map, NR_IRQS,
> + machine_gsi + 1) )
> + {
> + pirq_guest_eoi(irq_map->dom, machine_gsi);
> + }
> }
>
> int pt_irq_create_bind_vtd(
>
> --
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