From: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Date: Fri, 23 Nov 2018 21:26:40 +0000 (+0100)
Subject: eal: fix multi-process hotplug if already probed
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=d27eed313929685fda8c7f223f897a7e7baa9f63;p=dpdk.git

eal: fix multi-process hotplug if already probed

When primary process receives an IPC attach request
of a device that's already locally-attached, it
doesn't setup its variables properly and is prone to
segfaulting on a subsequent rollback.

`ret = local_dev_probe(req->devargs, &dev)`

The above function will set `dev` pointer to the
proper device *unless* it returns with error. One of
those errors is -EEXIST, which the hotplug function
explicitly ignores. For -EEXIST, it proceeds with
attaching the device and expects the dev pointer to
be valid.

This patch makes `local_dev_probe` set the dev pointer
even if it returns -EEXIST.

Fixes: ac9e4a17370f ("eal: support attach/detach shared device from secondary")

Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
---

diff --git a/lib/librte_eal/common/eal_common_dev.c b/lib/librte_eal/common/eal_common_dev.c
index 1fdc9ab170..a08dc085fd 100644
--- a/lib/librte_eal/common/eal_common_dev.c
+++ b/lib/librte_eal/common/eal_common_dev.c
@@ -168,16 +168,14 @@ local_dev_probe(const char *devargs, struct rte_device **new_dev)
 	}
 
 	ret = dev->bus->plug(dev);
-	if (ret) {
-		if (rte_dev_is_probed(dev)) /* if already succeeded earlier */
-			return ret; /* no rollback */
+	if (ret && !rte_dev_is_probed(dev)) { /* if hasn't ever succeeded */
 		RTE_LOG(ERR, EAL, "Driver cannot attach the device (%s)\n",
 			dev->name);
 		goto err_devarg;
 	}
 
 	*new_dev = dev;
-	return 0;
+	return ret;
 
 err_devarg:
 	if (rte_devargs_remove(da) != 0) {