diff options
| author | Amol Grover <frextrite@gmail.com> | 2020-01-17 16:25:22 +0300 |
|---|---|---|
| committer | Corey Minyard <cminyard@mvista.com> | 2020-03-12 22:56:00 +0300 |
| commit | 4f1885a7b347a905cd9ed7deb6472a9688637432 (patch) | |
| tree | bf8f13d3f1bfce9b896753a737c907ba481ebb0f /drivers/char | |
| parent | 3cc6e2c599cdca573a8f347aea5da4c855ff5a78 (diff) | |
| download | linux-4f1885a7b347a905cd9ed7deb6472a9688637432.tar.xz | |
drivers: char: ipmi: ipmi_msghandler: Pass lockdep expression to RCU lists
intf->cmd_rcvrs is traversed with list_for_each_entry_rcu
outside an RCU read-side critical section but under the
protection of intf->cmd_rcvrs_mutex.
ipmi_interfaces is traversed using list_for_each_entry_rcu
outside an RCU read-side critical section but under the protection
of ipmi_interfaces_mutex.
Hence, add the corresponding lockdep expression to the list traversal
primitive to silence false-positive lockdep warnings, and
harden RCU lists.
Add macro for the corresponding lockdep expression to make the code
clean and concise.
Signed-off-by: Amol Grover <frextrite@gmail.com>
Message-Id: <20200117132521.31020-1-frextrite@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/ipmi/ipmi_msghandler.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index cad9563f8f48..64ba16dcb681 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -618,6 +618,8 @@ static DEFINE_MUTEX(ipmidriver_mutex); static LIST_HEAD(ipmi_interfaces); static DEFINE_MUTEX(ipmi_interfaces_mutex); +#define ipmi_interfaces_mutex_held() \ + lockdep_is_held(&ipmi_interfaces_mutex) static struct srcu_struct ipmi_interfaces_srcu; /* @@ -1321,7 +1323,8 @@ static void _ipmi_destroy_user(struct ipmi_user *user) * synchronize_srcu()) then free everything in that list. */ mutex_lock(&intf->cmd_rcvrs_mutex); - list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) { + list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link, + lockdep_is_held(&intf->cmd_rcvrs_mutex)) { if (rcvr->user == user) { list_del_rcu(&rcvr->link); rcvr->next = rcvrs; @@ -1599,7 +1602,8 @@ static struct cmd_rcvr *find_cmd_rcvr(struct ipmi_smi *intf, { struct cmd_rcvr *rcvr; - list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) { + list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link, + lockdep_is_held(&intf->cmd_rcvrs_mutex)) { if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd) && (rcvr->chans & (1 << chan))) return rcvr; @@ -1614,7 +1618,8 @@ static int is_cmd_rcvr_exclusive(struct ipmi_smi *intf, { struct cmd_rcvr *rcvr; - list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) { + list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link, + lockdep_is_held(&intf->cmd_rcvrs_mutex)) { if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd) && (rcvr->chans & chans)) return 0; @@ -3450,7 +3455,8 @@ int ipmi_add_smi(struct module *owner, /* Look for a hole in the numbers. */ i = 0; link = &ipmi_interfaces; - list_for_each_entry_rcu(tintf, &ipmi_interfaces, link) { + list_for_each_entry_rcu(tintf, &ipmi_interfaces, link, + ipmi_interfaces_mutex_held()) { if (tintf->intf_num != i) { link = &tintf->link; break; |