ipmi: Disable some operations during a panic

BugLink: https://bugs.launchpad.net/bugs/1953387
[ Upstream commit b36eb5e7b75a756baa64909a176dd4269ee05a8b ]

Don't do kfree or other risky things when oops_in_progress is set.
It's easy enough to avoid doing them

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index ac656a6d5daf17146ca75f16999147dad590566f..bd3c9fb029fa5fb00b346e7627575ad624252968 100644 (file)
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -4797,7 +4797,9 @@ static atomic_t recv_msg_inuse_count = ATOMIC_INIT(0);
 static void free_smi_msg(struct ipmi_smi_msg *msg)
 {
        atomic_dec(&smi_msg_inuse_count);
-       kfree(msg);
+       /* Try to keep as much stuff out of the panic path as possible. */
+       if (!oops_in_progress)
+               kfree(msg);
 }
 
 struct ipmi_smi_msg *ipmi_alloc_smi_msg(void)
@@ -4816,7 +4818,9 @@ EXPORT_SYMBOL(ipmi_alloc_smi_msg);
 static void free_recv_msg(struct ipmi_recv_msg *msg)
 {
        atomic_dec(&recv_msg_inuse_count);
-       kfree(msg);
+       /* Try to keep as much stuff out of the panic path as possible. */
+       if (!oops_in_progress)
+               kfree(msg);
 }
 
 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void)
@@ -4834,7 +4838,7 @@ static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void)
 
 void ipmi_free_recv_msg(struct ipmi_recv_msg *msg)
 {
-       if (msg->user)
+       if (msg->user && !oops_in_progress)
                kref_put(&msg->user->refcount, free_user);
        msg->done(msg);
 }

diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
index ae06e5402e9d523034c8fb541672c7e953b83cd2..72ad7fff64a7ac0f4bb8eb44518b2ccc924e919c 100644 (file)
--- a/drivers/char/ipmi/ipmi_watchdog.c
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -337,13 +337,17 @@ static atomic_t msg_tofree = ATOMIC_INIT(0);
 static DECLARE_COMPLETION(msg_wait);
 static void msg_free_smi(struct ipmi_smi_msg *msg)
 {
-       if (atomic_dec_and_test(&msg_tofree))
-               complete(&msg_wait);
+       if (atomic_dec_and_test(&msg_tofree)) {
+               if (!oops_in_progress)
+                       complete(&msg_wait);
+       }
 }
 static void msg_free_recv(struct ipmi_recv_msg *msg)
 {
-       if (atomic_dec_and_test(&msg_tofree))
-               complete(&msg_wait);
+       if (atomic_dec_and_test(&msg_tofree)) {
+               if (!oops_in_progress)
+                       complete(&msg_wait);
+       }
 }
 static struct ipmi_smi_msg smi_msg = {
        .done = msg_free_smi
@@ -429,8 +433,10 @@ static int _ipmi_set_timeout(int do_heartbeat)
        rv = __ipmi_set_timeout(&smi_msg,
                                &recv_msg,
                                &send_heartbeat_now);
-       if (rv)
+       if (rv) {
+               atomic_set(&msg_tofree, 0);
                return rv;
+       }
 
        wait_for_completion(&msg_wait);
 
@@ -575,6 +581,7 @@ restart:
                                      &recv_msg,
                                      1);
        if (rv) {
+               atomic_set(&msg_tofree, 0);
                pr_warn("heartbeat send failure: %d\n", rv);
                return rv;
        }