57 lines
2.4 KiB
Diff
57 lines
2.4 KiB
Diff
|
From b2120f0a316470369451103d9d1b50b2d13cd68b Mon Sep 17 00:00:00 2001
|
||
|
|
From: Luo Yifan <luoyifan_yewu@cmss.chinamobile.com>
|
||
|
|
Date: Thu, 28 Mar 2024 13:58:20 +0800
|
||
|
|
Subject: [PATCH] ivshmem.c: change endianness to LITTLE_ENDIAN
|
||
|
|
MIME-Version: 1.0
|
||
|
|
Content-Type: text/plain; charset=UTF-8
|
||
|
|
Content-Transfer-Encoding: 8bit
|
||
|
|
|
||
|
|
cherry picked from commit ef80a708b57ddc8f605d9982bfaa0536e720ed9f
|
||
|
|
|
||
|
|
The ivshmem device, as with most PCI devices, uses little endian byte
|
||
|
|
order. However, the endianness of its mmio_ops is marked as
|
||
|
|
DEVICE_NATIVE_ENDIAN. This presents not only the usual problems with big
|
||
|
|
endian hosts but also with PowerPC little endian hosts as well, since
|
||
|
|
the Power architecture in QEMU uses big endian hardware (XIVE controller,
|
||
|
|
PCI Host Bridges, etc) even if the host is in little endian byte order.
|
||
|
|
|
||
|
|
As it is today, the IVPosition of the device will be byte swapped when
|
||
|
|
running in Power BE and LE. This can be seen by changing the existing
|
||
|
|
qtest 'ivshmem-test' to run in ppc64 hosts and printing the IVPOSITION
|
||
|
|
regs in test_ivshmem_server() right after the VM ids assert. For x86_64
|
||
|
|
the VM id values read are '0' and '1', for ppc64 (tested in a Power8
|
||
|
|
RHEL 7.9 BE server) and ppc64le (tested in a Power9 RHEL 8.6 LE server)
|
||
|
|
the ids will be '0' and '0x1000000'.
|
||
|
|
|
||
|
|
Change this device to LITTLE_ENDIAN fixes the issue for Power hosts of
|
||
|
|
both endianness, and every other big-endian architecture that might use
|
||
|
|
this device, without impacting x86 users.
|
||
|
|
|
||
|
|
Fixes: cb06608e17f8 ("ivshmem: convert to memory API")
|
||
|
|
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/168
|
||
|
|
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
|
||
|
|
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
|
||
|
|
Message-Id: <20211124092948.335389-2-danielhb413@gmail.com>
|
||
|
|
Signed-off-by: Cédric Le Goater <clg@kaod.org>
|
||
|
|
Signed-off-by: Luo Yifan <luoyifan_yewu@cmss.chinamobile.com>
|
||
|
|
---
|
||
|
|
hw/misc/ivshmem.c | 2 +-
|
||
|
|
1 file changed, 1 insertion(+), 1 deletion(-)
|
||
|
|
|
||
|
|
diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
|
||
|
|
index 05f06ed6cf..4093c59079 100644
|
||
|
|
--- a/hw/misc/ivshmem.c
|
||
|
|
+++ b/hw/misc/ivshmem.c
|
||
|
|
@@ -243,7 +243,7 @@ static uint64_t ivshmem_io_read(void *opaque, hwaddr addr,
|
||
|
|
static const MemoryRegionOps ivshmem_mmio_ops = {
|
||
|
|
.read = ivshmem_io_read,
|
||
|
|
.write = ivshmem_io_write,
|
||
|
|
- .endianness = DEVICE_NATIVE_ENDIAN,
|
||
|
|
+ .endianness = DEVICE_LITTLE_ENDIAN,
|
||
|
|
.impl = {
|
||
|
|
.min_access_size = 4,
|
||
|
|
.max_access_size = 4,
|
||
|
|
--
|
||
|
|
2.27.0
|
||
|
|
|