| Message ID | 8a4f355e-c381-412c-8949-061851d0f7e2@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | IOMMU: XSA-373 follow-on | expand |
> From: Jan Beulich > Sent: Wednesday, June 9, 2021 5:29 PM > > While no longer an immediate problem with flushes no longer timing out, > errors (if any) get properly reported by iommu_flush_iotlb_{dsi,psi}(). > Overwriting such an error with, perhaps, a success indicator received > from another IOMMU will misguide callers. Record the first error, but > don't bail from the loop (such that further necessary invalidation gets > carried out on a best effort basis). > > Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> > > --- a/xen/drivers/passthrough/vtd/iommu.c > +++ b/xen/drivers/passthrough/vtd/iommu.c > @@ -643,7 +643,7 @@ static int __must_check iommu_flush_iotl > struct vtd_iommu *iommu; > bool_t flush_dev_iotlb; > int iommu_domid; > - int rc = 0; > + int ret = 0; > > /* > * No need pcideves_lock here because we have flush > @@ -651,6 +651,8 @@ static int __must_check iommu_flush_iotl > */ > for_each_drhd_unit ( drhd ) > { > + int rc; > + > iommu = drhd->iommu; > > if ( !test_bit(iommu->index, &hd->arch.vtd.iommu_bitmap) ) > @@ -673,13 +675,12 @@ static int __must_check iommu_flush_iotl > flush_dev_iotlb); > > if ( rc > 0 ) > - { > iommu_flush_write_buffer(iommu); > - rc = 0; > - } > + else if ( !ret ) > + ret = rc; > } > > - return rc; > + return ret; > } > > static int __must_check iommu_flush_iotlb_pages(struct domain *d, >
--- a/xen/drivers/passthrough/vtd/iommu.c +++ b/xen/drivers/passthrough/vtd/iommu.c @@ -643,7 +643,7 @@ static int __must_check iommu_flush_iotl struct vtd_iommu *iommu; bool_t flush_dev_iotlb; int iommu_domid; - int rc = 0; + int ret = 0; /* * No need pcideves_lock here because we have flush @@ -651,6 +651,8 @@ static int __must_check iommu_flush_iotl */ for_each_drhd_unit ( drhd ) { + int rc; + iommu = drhd->iommu; if ( !test_bit(iommu->index, &hd->arch.vtd.iommu_bitmap) ) @@ -673,13 +675,12 @@ static int __must_check iommu_flush_iotl flush_dev_iotlb); if ( rc > 0 ) - { iommu_flush_write_buffer(iommu); - rc = 0; - } + else if ( !ret ) + ret = rc; } - return rc; + return ret; } static int __must_check iommu_flush_iotlb_pages(struct domain *d,
While no longer an immediate problem with flushes no longer timing out, errors (if any) get properly reported by iommu_flush_iotlb_{dsi,psi}(). Overwriting such an error with, perhaps, a success indicator received from another IOMMU will misguide callers. Record the first error, but don't bail from the loop (such that further necessary invalidation gets carried out on a best effort basis). Signed-off-by: Jan Beulich <jbeulich@suse.com>