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 &error_fatal, the user
can't see this additional information, because exit() happens in
error_setg earlier than information is added [1].
The nbd_co_do_receive_one_chunk() passes @errp to error_prepend()
without ERRP_GUARD(), and though its @errp parameter points to its
caller's local_err, to follow the requirement of @errp, 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: Eric Blake <ebl...@redhat.com>
Cc: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru>
Cc: Kevin Wolf <kw...@redhat.com>
Cc: Hanna Reitz <hre...@redhat.com>
Cc: qemu-bl...@nongnu.org
Signed-off-by: Zhao Liu <zhao1....@intel.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru>
Message-ID: <20240311033822.3142585-6-zhao1....@linux.intel.com>
Signed-off-by: Thomas Huth <th...@redhat.com>
---
block/nbd.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/block/nbd.c b/block/nbd.c
index b9d4f935e0..ef05f7cdfd 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -852,6 +852,7 @@ static coroutine_fn int nbd_co_do_receive_one_chunk(
BDRVNBDState *s, uint64_t cookie, bool only_structured,
int *request_ret, QEMUIOVector *qiov, void **payload, Error **errp)
{
+ ERRP_GUARD();
int ret;
int i = COOKIE_TO_INDEX(cookie);
void *local_payload = NULL;
--
2.44.0
