power: fix error messages

Function strerror(errno) has built strings only for non-negative errno values.
for negative values of errno it describe error as "Unknown error -errno"
to be more descriptive i put string "channel not found" taken from header.

The negative argument will be interpreted as a very large unsigned value.

Coverity issue: 13266
Coverity issue: 13269
Fixes: 445c6528b55f ("power: common interface for guest and host")

Signed-off-by: Daniel Mrzyglod <danielx.t.mrzyglod@intel.com>

diff --git a/lib/librte_power/guest_channel.c b/lib/librte_power/guest_channel.c
index d6b6d0a..85c92fa 100644 (file)
--- a/lib/librte_power/guest_channel.c
+++ b/lib/librte_power/guest_channel.c
@@ -103,8 +103,10 @@ guest_channel_host_connect(const char *path, unsigned lcore_id)
        global_fds[lcore_id] = fd;
        ret = guest_channel_send_msg(&pkt, lcore_id);
        if (ret != 0) {
-               RTE_LOG(ERR, GUEST_CHANNEL, "Error on channel '%s' communications "
-                               "test: %s\n", fd_path, strerror(ret));
+               RTE_LOG(ERR, GUEST_CHANNEL,
+                               "Error on channel '%s' communications test: %s\n",
+                               fd_path, ret > 0 ? strerror(ret) :
+                               "channel not connected");
                goto error;
        }
        RTE_LOG(INFO, GUEST_CHANNEL, "Channel '%s' is now connected\n", fd_path);

diff --git a/lib/librte_power/rte_power_kvm_vm.c b/lib/librte_power/rte_power_kvm_vm.c
index 7bb2774..a1badf3 100644 (file)
--- a/lib/librte_power/rte_power_kvm_vm.c
+++ b/lib/librte_power/rte_power_kvm_vm.c
@@ -106,7 +106,8 @@ send_msg(unsigned lcore_id, uint32_t scale_direction)
        ret = guest_channel_send_msg(&pkt[lcore_id], lcore_id);
        if (ret == 0)
                return 1;
-       RTE_LOG(DEBUG, POWER, "Error sending message: %s\n", strerror(ret));
+       RTE_LOG(DEBUG, POWER, "Error sending message: %s\n",
+                       ret > 0 ? strerror(ret) : "channel not connected");
        return -1;
 }