在 2022/1/13 下午3:05, Michael S. Tsirkin 写道:
On Thu, Jan 13, 2022 at 11:35:19AM +0800, Peter Xu wrote:
On Wed, Jan 05, 2022 at 12:19:43PM +0800, Jason Wang wrote:
We use to warn on wrong rid2pasid entry. But this error could be
triggered by the guest and could happens during initialization. So
let's don't warn in this case.
Signed-off-by: Jason Wang <jasow...@redhat.com>
---
hw/i386/intel_iommu.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 4c6c016388..f2c7a23712 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -1524,8 +1524,10 @@ static bool vtd_dev_pt_enabled(IntelIOMMUState *s,
VTDContextEntry *ce)
if (s->root_scalable) {
ret = vtd_ce_get_rid2pasid_entry(s, ce, &pe);
if (ret) {
- error_report_once("%s: vtd_ce_get_rid2pasid_entry error: %"PRId32,
- __func__, ret);
+ /*
+ * This error is guest triggerable. We should assumt PT
+ * not enabled for safety.
+ */
return false;
}
return (VTD_PE_GET_TYPE(&pe) == VTD_SM_PASID_ENTRY_PT);
--
2.25.1
No strong opinion, but the thing is mostly all error_report_once() in this file
is guest triggerable. If we remove this one then it's debatable on whether we
want to remove all.
IMHO we used the _once() variant just for this: it won't go into any form of
DoS, meanwhile we'll still get some information (as hypervisor) that the guest
OS may not be trustworthy.
So from that pov it's still useful? Or is this error very special in some way?
Thanks,
Well we have LOG_GUEST_ERROR for guest errors now.
Ok, but this is not necessarily a guest error. (Inferring from the
comment in vtd_as_pt_enabled()).
Thanks
--
Peter Xu
