Hello, On 2/29/24 15:39, Zhao Liu wrote:
From: Zhao Liu <[email protected]>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_get_group() passes @errp to error_prepend(). Its @errp is from vfio_attach_device(), which @errp parameter 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 <[email protected]> Cc: "Cédric Le Goater" <[email protected]> Signed-off-by: Zhao Liu <[email protected]>
Reviewed-by: Cédric Le Goater <[email protected]> Thanks, C.
