From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43257) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZWyg9-0007FK-D9 for qemu-devel@nongnu.org; Tue, 01 Sep 2015 23:25:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZWyg8-0006lV-Mt for qemu-devel@nongnu.org; Tue, 01 Sep 2015 23:25:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34346) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZWyg8-0006kw-HW for qemu-devel@nongnu.org; Tue, 01 Sep 2015 23:25:40 -0400 From: Jason Wang Date: Wed, 2 Sep 2015 11:25:22 +0800 Message-Id: <1441164325-14417-6-git-send-email-jasowang@redhat.com> In-Reply-To: <1441164325-14417-1-git-send-email-jasowang@redhat.com> References: <1441164325-14417-1-git-send-email-jasowang@redhat.com> Subject: [Qemu-devel] [PATCH V2 5/8] memory: don't try to adjust endianness for zero length eventfd List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , mst@redhat.com, Jason Wang , cornelia.huck@de.ibm.com, Paolo Bonzini , Greg Kurz 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 Cc: Peter Maydell Cc: Paolo Bonzini Signed-off-by: Jason Wang --- 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