On 2/29/24 15:39, Zhao Liu wrote:
From: Zhao Liu <zhao1....@intel.com>
As the comment in qapi/error, passing @errp to error_prepend() requires
ERRP_GUARD():
* = Why, when and how to use ERRP_GUARD() =
*
* Without ERRP_GUARD(), use of the @errp parameter is restricted:
...
* - It should not be passed to error_prepend(), error_vprepend() or
* error_append_hint(), because that doesn't work with &error_fatal.
* ERRP_GUARD() lifts these restrictions.
*
* To use ERRP_GUARD(), add it right at the beginning of the function.
* @errp can then be used without worrying about the argument being
* NULL or &error_fatal.
ERRP_GUARD() could avoid the case when @errp is the pointer of
error_fatal, the user can't see this additional information, because
exit() happens in error_setg earlier than information is added [1].
The vfio_platform_realize() passes @errp to error_prepend(), and as a
DeviceClass.realize method, its @errp is so widely sourced that it is
necessary to protect it with ERRP_GUARD().
To avoid the issue like [1] said, add missing ERRP_GUARD() at the
beginning of this function.
[1]: Issue description in the commit message of commit ae7c80a7bd73
("error: New macro ERRP_GUARD()").
Cc: Alex Williamson <alex.william...@redhat.com>
Cc: "Cédric Le Goater" <c...@redhat.com>
Signed-off-by: Zhao Liu <zhao1....@intel.com>
Reviewed-by: Cédric Le Goater <c...@redhat.com>
Thanks,
C.
---
hw/vfio/platform.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
index a8d9b7da633e..dcd2365fb353 100644
--- a/hw/vfio/platform.c
+++ b/hw/vfio/platform.c
@@ -576,6 +576,7 @@ static int vfio_base_device_init(VFIODevice *vbasedev,
Error **errp)
*/
static void vfio_platform_realize(DeviceState *dev, Error **errp)
{
+ ERRP_GUARD();
VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(dev);
SysBusDevice *sbdev = SYS_BUS_DEVICE(dev);
VFIODevice *vbasedev = &vdev->vbasedev;
