From e63a8e1933a2218cf801e46dd01bd8cca4a555ec Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Fri, 12 Aug 2011 16:01:02 -0700 Subject: [PATCH] target: Make locking in transport_deregister_session() IRQ safe At least the tcm_qla2xxx fabric driver calls into transport_deregister_session() while holding an IRQ-disabled spinlock, so the inner locking needs to use spin_lock_irqsave() instead of spin_lock_bh(). This fixes warnings seen with tcm_qla2xxx like: WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0x98/0xb0() Call Trace: [] warn_slowpath_common+0x7f/0xc0 [] warn_slowpath_null+0x1a/0x20 [] local_bh_enable_ip+0x98/0xb0 [] _raw_spin_unlock_bh+0x14/0x20 [] transport_deregister_session+0x96/0x180 [target_core_mod] [] tcm_qla2xxx_free_session+0xd1/0x170 [tcm_qla2xxx] [] qla_tgt_sess_put+0xc3/0x140 [qla2xxx] [] qla_tgt_stop_phase1+0x8f/0x2c0 [qla2xxx] [] tcm_qla2xxx_tpg_store_enable+0x6e/0xd0 [tcm_qla2xxx] [] target_fabric_tpg_attr_store+0x39/0x40 [target_core_mod] [] configfs_write_file+0xbd/0x120 [configfs] [] vfs_write+0xc6/0x180 [] sys_write+0x51/0x90 [] system_call_fastpath+0x16/0x1b Signed-off-by: Roland Dreier Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 9cc49d1b5b1f..8d0c58ea6316 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -389,17 +389,18 @@ void transport_deregister_session(struct se_session *se_sess) { struct se_portal_group *se_tpg = se_sess->se_tpg; struct se_node_acl *se_nacl; + unsigned long flags; if (!se_tpg) { transport_free_session(se_sess); return; } - spin_lock_bh(&se_tpg->session_lock); + spin_lock_irqsave(&se_tpg->session_lock, flags); list_del(&se_sess->sess_list); se_sess->se_tpg = NULL; se_sess->fabric_sess_ptr = NULL; - spin_unlock_bh(&se_tpg->session_lock); + spin_unlock_irqrestore(&se_tpg->session_lock, flags); /* * Determine if we need to do extra work for this initiator node's @@ -407,22 +408,22 @@ void transport_deregister_session(struct se_session *se_sess) */ se_nacl = se_sess->se_node_acl; if (se_nacl) { - spin_lock_bh(&se_tpg->acl_node_lock); + spin_lock_irqsave(&se_tpg->acl_node_lock, flags); if (se_nacl->dynamic_node_acl) { if (!se_tpg->se_tpg_tfo->tpg_check_demo_mode_cache( se_tpg)) { list_del(&se_nacl->acl_list); se_tpg->num_node_acls--; - spin_unlock_bh(&se_tpg->acl_node_lock); + spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags); core_tpg_wait_for_nacl_pr_ref(se_nacl); core_free_device_list_for_node(se_nacl, se_tpg); se_tpg->se_tpg_tfo->tpg_release_fabric_acl(se_tpg, se_nacl); - spin_lock_bh(&se_tpg->acl_node_lock); + spin_lock_irqsave(&se_tpg->acl_node_lock, flags); } } - spin_unlock_bh(&se_tpg->acl_node_lock); + spin_unlock_irqrestore(&se_tpg->acl_node_lock, flags); } transport_free_session(se_sess); -- 2.20.1