[PATCH 5.15 236/917] ipmi: Disable some operations during a panic

Greg Kroah-Hartman
2021-11-16T00:59:31Z

From: Corey Minyard <cminyard@mvista.com>

[ 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>
---
drivers/char/ipmi/ipmi_msghandler.c | 10 +++++++---
drivers/char/ipmi/ipmi_watchdog.c | 17 ++++++++++++-----
2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index e96cb5c4f97a3..a08f53f208bfe 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -4789,7 +4789,9 @@ 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)
@@ -4808,7 +4810,9 @@ 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)
@@ -4826,7 +4830,7 @@ 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 f855a9665c284..883b4a3410122 100644
--- a/drivers/char/ipmi/ipmi_watchdog.c
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -342,13 +342,17 @@ 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
@@ -434,8 +438,10 @@ 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);

@@ -580,6 +586,7 @@ restart:
&recv_msg,
1);
if (rv) {
+ atomic_set(&msg_tofree, 0);
pr_warn("heartbeat send failure: %d\n", rv);
return rv;
}
--
2.33.0