There's no need to adjust endianness for zero length eventfd since the data wrote was actually ignored by kernel. So skip the adjust in this case to fix a possible crash when trying to use wildcard mmio eventfd in ppc.
Cc: Greg Kurz <[email protected]> Cc: Peter Maydell <[email protected]> Cc: Paolo Bonzini <[email protected]> Signed-off-by: Jason Wang <[email protected]> --- memory.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/memory.c b/memory.c index 0d8b2d9..de2d999 100644 --- a/memory.c +++ b/memory.c @@ -1653,7 +1653,9 @@ void memory_region_add_eventfd(MemoryRegion *mr, }; unsigned i; - adjust_endianness(mr, &mrfd.data, size); + if (size) { + adjust_endianness(mr, &mrfd.data, size); + } memory_region_transaction_begin(); for (i = 0; i < mr->ioeventfd_nb; ++i) { if (memory_region_ioeventfd_before(mrfd, mr->ioeventfds[i])) { @@ -1686,7 +1688,9 @@ void memory_region_del_eventfd(MemoryRegion *mr, }; unsigned i; - adjust_endianness(mr, &mrfd.data, size); + if (size) { + adjust_endianness(mr, &mrfd.data, size); + } memory_region_transaction_begin(); for (i = 0; i < mr->ioeventfd_nb; ++i) { if (memory_region_ioeventfd_equal(mrfd, mr->ioeventfds[i])) { -- 2.1.4
