RDS: Fix m_rs_lock deadlock

rs_send_drop_to() is called during socket close. If it takes
m_rs_lock without disabling interrupts, then
rds_send_remove_from_sock() can run from the rx completion
handler and thus deadlock.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Andy Grover
2009-04-01 08:20:18 +00:00
committed by David S. Miller
parent f1782852ad
commit f1cffcbfcc

View File

@@ -615,7 +615,7 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest)
{ {
struct rds_message *rm, *tmp; struct rds_message *rm, *tmp;
struct rds_connection *conn; struct rds_connection *conn;
unsigned long flags; unsigned long flags, flags2;
LIST_HEAD(list); LIST_HEAD(list);
int wake = 0; int wake = 0;
@@ -651,9 +651,9 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest)
list_for_each_entry(rm, &list, m_sock_item) { list_for_each_entry(rm, &list, m_sock_item) {
/* We do this here rather than in the loop above, so that /* We do this here rather than in the loop above, so that
* we don't have to nest m_rs_lock under rs->rs_lock */ * we don't have to nest m_rs_lock under rs->rs_lock */
spin_lock(&rm->m_rs_lock); spin_lock_irqsave(&rm->m_rs_lock, flags2);
rm->m_rs = NULL; rm->m_rs = NULL;
spin_unlock(&rm->m_rs_lock); spin_unlock_irqrestore(&rm->m_rs_lock, flags2);
/* /*
* If we see this flag cleared then we're *sure* that someone * If we see this flag cleared then we're *sure* that someone