Re: [Xen-devel] [PATCH v2] x86/passthrough: fix migration of MSI when using posted interrupts

[Jan Beulich <jbeulich@xxxxxxxx>]

On 09.10.2019 14:52, Roger Pau Monne wrote:
> When using posted interrupts and the guest migrates MSI from vCPUs Xen
> needs to flush any pending PIRR vectors on the previous vCPU, or else
> those vectors could get wrongly injected at a later point when the MSI
> fields are already updated.
> 
> Rename sync_pir_to_irr to vlapic_sync_pir_to_irr and export it so it
> can be called when updating the posted interrupt descriptor field in
> pi_update_irte. While there also remove the unlock_out from
> pi_update_irte, it's used in a single goto and removing it makes the
> function smaller.
> 
> Note that PIRR is synced to IRR both in pt_irq_destroy_bind and
> pt_irq_create_bind when the interrupt delivery data is being updated.
> 
> Also store the vCPU ID in multi-destination mode when using posted
> interrupts and the interrupt is bound to a single vCPU in order for
> posted interrupts to be used.
> 
> While there guard pi_update_irte with CONFIG_HVM since it's only used
> with HVM guests.
> 
> Reported-by: Joe Jin <joe.jin@xxxxxxxxxx>
> Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>

Like for the other patch I'd prefer to wait a little with committing
(even if the VT-d ack appeared quickly) until hopefully a Tested-by
could be provided.

Jan

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel