if an entry has non inclusive overlap with the notifier, print warning
message and do not do notification for it.
Out of scope mapping/unmapping would cause problem, as in below case:
1. initially there are two notifiers with ranges
0-0xfedfffff, 0xfef00000-0xffffffffffffffff,
IOVAs from 0x3c000000 - 0x3c1fffff is in shadow page table.
2. in vfio, memory_region_register_iommu_notifier() is followed by
memory_region_iommu_replay(), which will first call address space
unmap,
and walk and add back all entries in vtd shadow page table. e.g.
(1) for notifier 0-0xfedfffff,
IOVAs from 0 - 0xffffffff get unmapped,
and IOVAs from 0x3c000000 - 0x3c1fffff get mapped
(2) for notifier 0xfef00000-0xffffffffffffffff
IOVAs from 0 - 0x7fffffffff get unmapped,
but IOVAs from 0x3c000000 - 0x3c1fffff cannot get mapped back.
Cc: Eric Auger <eric.au...@redhat.com>
Cc: Peter Xu <pet...@redhat.com>
Signed-off-by: Yan Zhao <yan.y.z...@intel.com>
---
v5:
1. still using warn_report instead of "assert"
2. returning at the end to refuse notification for entry which has non
inclusive overlap with the notifier.
3. updated commit title and warning message.
v4:
1. modified commit title
2. using "assert" instead of printing warning message
v3:
refined code style and message format
v2:
1. added a local variable entry_end (Eric Auger)
2. using PRIx64 as format for address range in warning message
(Eric Auger)
---
memory.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/memory.c b/memory.c
index 0a089a7..fe0d08d 100644
--- a/memory.c
+++ b/memory.c
@@ -1937,13 +1937,13 @@ void memory_region_notify_one(IOMMUNotifier *notifier,
IOMMUTLBEntry *entry)
{
IOMMUNotifierFlag request_flags;
+ hwaddr entry_end = entry->iova + entry->addr_mask;
/*
* Skip the notification if the notification does not overlap
* with registered range.
*/
- if (notifier->start > entry->iova + entry->addr_mask ||
- notifier->end < entry->iova) {
+ if (notifier->start > entry_end || notifier->end < entry->iova) {
return;
}
@@ -1953,6 +1953,18 @@ void memory_region_notify_one(IOMMUNotifier *notifier,
request_flags = IOMMU_NOTIFIER_UNMAP;
}
+ if (entry->iova < notifier->start || entry_end > notifier->end) {
+ warn_report("IOMMUTLBEntry 0x%" PRIx64 " - 0x%" PRIx64
+ " has non inclusive overlap with notifier 0x%" PRIx64
+ " - 0x%" PRIx64 ". %s is not allowed."
+ " Try to divide it into smaller sections.",
+ entry->iova, entry_end,
+ notifier->start, notifier->end,
+ (request_flags == IOMMU_NOTIFIER_MAP) ?
+ "Mapping" : "Unmapping");
+ return;
+ }
+
if (notifier->notifier_flags & request_flags) {
notifier->notify(notifier, entry);
}
--
2.7.4
