From: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
To: dev@dpdk.org
Cc: thomas@monjalon.net,
Darek Stojaczyk <dariusz.stojaczyk@intel.com>,
qi.z.zhang@intel.com
Subject: [dpdk-dev] [PATCH] dev: fix attach rollback of a device that was already attached
Date: Fri, 23 Nov 2018 15:45:06 +0100 [thread overview]
Message-ID: <20181123144506.95367-1-dariusz.stojaczyk@intel.com> (raw)
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.
Despite this patch being a fix, it also introduces
a design decision - when any secondary process fails
to attach a device, the primary process that already
had the device attached won't attempt to detach that
device locally as a part of the rollback routine.
Primary process would have already printed a message
"Failed to [...] on secondary" and now it will also
print a warning "Devices may not be in sync [...]".
Fixes: ac9e4a17370f ("eal: support attach/detach shared device from secondary")
Cc: qi.z.zhang@intel.com
Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
---
lib/librte_eal/common/hotplug_mp.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/lib/librte_eal/common/hotplug_mp.c b/lib/librte_eal/common/hotplug_mp.c
index 7c9fcc46c..7ee074a31 100644
--- a/lib/librte_eal/common/hotplug_mp.c
+++ b/lib/librte_eal/common/hotplug_mp.c
@@ -88,7 +88,7 @@ __handle_secondary_request(void *param)
(const struct eal_dev_mp_req *)msg->param;
struct eal_dev_mp_req tmp_req;
struct rte_devargs *da;
- struct rte_device *dev;
+ struct rte_device *dev = NULL;
struct rte_bus *bus;
int ret = 0;
@@ -168,7 +168,15 @@ __handle_secondary_request(void *param)
if (req->t == EAL_DEV_REQ_TYPE_ATTACH) {
tmp_req.t = EAL_DEV_REQ_TYPE_ATTACH_ROLLBACK;
eal_dev_hotplug_request_to_secondary(&tmp_req);
- local_dev_remove(dev);
+ if (dev == NULL) {
+ /* device was already attached at the time we got the
+ * request, don't detach it now.
+ */
+ RTE_LOG(WARNING, EAL,
+ "Devices in secondary may not sync with primary\n");
+ } else {
+ local_dev_remove(dev);
+ }
} else {
tmp_req.t = EAL_DEV_REQ_TYPE_DETACH_ROLLBACK;
eal_dev_hotplug_request_to_secondary(&tmp_req);
--
2.17.1
next reply other threads:[~2018-11-23 14:50 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-23 14:45 Darek Stojaczyk [this message]
2018-11-23 19:10 ` Zhang, Qi Z
2018-11-23 20:29 ` Stojaczyk, Dariusz
2018-11-23 21:26 ` [dpdk-dev] [PATCH v2] " Darek Stojaczyk
2018-11-25 12:25 ` Thomas Monjalon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181123144506.95367-1-dariusz.stojaczyk@intel.com \
--to=dariusz.stojaczyk@intel.com \
--cc=dev@dpdk.org \
--cc=qi.z.zhang@intel.com \
--cc=thomas@monjalon.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).