[PATCH v2 1/4] pdump: fix setting rte_errno on mp error

[Stephen Hemminger <stephen@networkplumber.org>]

The response from MP server sets err_value to negative
on error. The convention for rte_errno is to use a positive
value on error. This makes errors like duplicate registration
show up with the correct error value.

Fixes: 660098d61f57 ("pdump: use generic multi-process channel")
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/pdump/rte_pdump.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/pdump/rte_pdump.c b/lib/pdump/rte_pdump.c
index 53cca1034d41..a70085bd0211 100644
--- a/lib/pdump/rte_pdump.c
+++ b/lib/pdump/rte_pdump.c
@@ -564,9 +564,10 @@ pdump_prepare_client_request(const char *device, uint16_t queue,
 	if (rte_mp_request_sync(&mp_req, &mp_reply, &ts) == 0) {
 		mp_rep = &mp_reply.msgs[0];
 		resp = (struct pdump_response *)mp_rep->param;
-		rte_errno = resp->err_value;
-		if (!resp->err_value)
+		if (resp->err_value == 0)
 			ret = 0;
+		else
+			rte_errno = -resp->err_value;
 		free(mp_reply.msgs);
 	}
 
-- 
2.39.2