[v3,7/7] net/netvsc: do not spin forever waiting for reply
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Commit Message
Because of bugs in driver or host a reply to a request might
never occur. Better to give an error than spin forever.
Fixes: 4e9c73e96e83 ("net/netvsc: add Hyper-V network device")
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
drivers/net/netvsc/hn_rndis.c | 30 ++++++++++++++++++++++++++++--
1 file changed, 28 insertions(+), 2 deletions(-)
@@ -10,6 +10,7 @@
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
+#include <time.h>
#include <rte_ethdev_driver.h>
#include <rte_ethdev.h>
@@ -34,6 +35,9 @@
#include "hn_rndis.h"
#include "ndis.h"
+#define RNDIS_TIMEOUT_SEC 5
+#define RNDIS_DELAY_MS 10
+
#define HN_RNDIS_XFER_SIZE 0x4000
#define HN_NDIS_TXCSUM_CAP_IP4 \
@@ -354,7 +358,7 @@ void hn_rndis_receive_response(struct hn_data *hv,
rte_smp_wmb();
if (rte_atomic32_cmpset(&hv->rndis_pending, hdr->rid, 0) == 0) {
- PMD_DRV_LOG(ERR,
+ PMD_DRV_LOG(NOTICE,
"received id %#x pending id %#x",
hdr->rid, (uint32_t)hv->rndis_pending);
}
@@ -377,6 +381,11 @@ static int hn_rndis_exec1(struct hn_data *hv,
return -EIO;
}
+ if (rid == 0) {
+ PMD_DRV_LOG(ERR, "Invalid request id");
+ return -EINVAL;
+ }
+
if (comp != NULL &&
rte_atomic32_cmpset(&hv->rndis_pending, 0, rid) == 0) {
PMD_DRV_LOG(ERR,
@@ -391,9 +400,26 @@ static int hn_rndis_exec1(struct hn_data *hv,
}
if (comp) {
+ time_t start = time(NULL);
+
/* Poll primary channel until response received */
- while (hv->rndis_pending == rid)
+ while (hv->rndis_pending == rid) {
+ if (hv->closed)
+ return -ENETDOWN;
+
+ if (time(NULL) - start > RNDIS_TIMEOUT_SEC) {
+ PMD_DRV_LOG(ERR,
+ "RNDIS response timed out");
+
+ rte_atomic32_cmpset(&hv->rndis_pending, rid, 0);
+ return -ETIMEDOUT;
+ }
+
+ if (rte_vmbus_chan_rx_empty(hv->primary->chan))
+ rte_delay_ms(RNDIS_DELAY_MS);
+
hn_process_events(hv, 0, 1);
+ }
memcpy(comp, hv->rndis_resp, comp_len);
}