From: Bart Van Assche bvanassche@acm.org
[ Upstream commit d4023db71108375e4194e92730ba0d32d7f07813 ]
This patch avoids that lockdep reports the following warning:
===================================================== WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected 5.1.0-rc1-dbg+ #11 Tainted: G W ----------------------------------------------------- rmdir/1478 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire: 00000000e7ac4607 (&(&k->k_lock)->rlock){+.+.}, at: klist_next+0x43/0x1d0
and this task is already holding: 00000000cf0baf5e (&(&ha->tgt.sess_lock)->rlock){-...}, at: tcm_qla2xxx_close_session+0x57/0xb0 [tcm_qla2xxx] which would create a new lock dependency: (&(&ha->tgt.sess_lock)->rlock){-...} -> (&(&k->k_lock)->rlock){+.+.}
but this new dependency connects a HARDIRQ-irq-safe lock: (&(&ha->tgt.sess_lock)->rlock){-...}
... which became HARDIRQ-irq-safe at: lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 qla2x00_fcport_event_handler+0x1f3d/0x22b0 [qla2xxx] qla2x00_async_login_sp_done+0x1dc/0x1f0 [qla2xxx] qla24xx_process_response_queue+0xa37/0x10e0 [qla2xxx] qla24xx_msix_rsp_q+0x79/0xf0 [qla2xxx] __handle_irq_event_percpu+0x79/0x3c0 handle_irq_event_percpu+0x70/0xf0 handle_irq_event+0x5a/0x8b handle_edge_irq+0x12c/0x310 handle_irq+0x192/0x20a do_IRQ+0x73/0x160 ret_from_intr+0x0/0x1d default_idle+0x23/0x1f0 arch_cpu_idle+0x15/0x20 default_idle_call+0x35/0x40 do_idle+0x2bb/0x2e0 cpu_startup_entry+0x1d/0x20 start_secondary+0x24d/0x2d0 secondary_startup_64+0xa4/0xb0
to a HARDIRQ-irq-unsafe lock: (&(&k->k_lock)->rlock){+.+.}
... which became HARDIRQ-irq-unsafe at: ... lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1 ---- ---- lock(&(&k->k_lock)->rlock); local_irq_disable(); lock(&(&ha->tgt.sess_lock)->rlock); lock(&(&k->k_lock)->rlock); <Interrupt> lock(&(&ha->tgt.sess_lock)->rlock);
*** DEADLOCK ***
4 locks held by rmdir/1478: #0: 000000002c7f1ba4 (sb_writers#10){.+.+}, at: mnt_want_write+0x32/0x70 #1: 00000000c85eb147 (&default_group_class[depth - 1]#2/1){+.+.}, at: do_rmdir+0x217/0x2d0 #2: 000000002b164d6f (&sb->s_type->i_mutex_key#13){++++}, at: vfs_rmdir+0x7e/0x1d0 #3: 00000000cf0baf5e (&(&ha->tgt.sess_lock)->rlock){-...}, at: tcm_qla2xxx_close_session+0x57/0xb0 [tcm_qla2xxx]
the dependencies between HARDIRQ-irq-safe lock and the holding lock: -> (&(&ha->tgt.sess_lock)->rlock){-...} ops: 127 { IN-HARDIRQ-W at: lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 qla2x00_fcport_event_handler+0x1f3d/0x22b0 [qla2xxx] qla2x00_async_login_sp_done+0x1dc/0x1f0 [qla2xxx] qla24xx_process_response_queue+0xa37/0x10e0 [qla2xxx] qla24xx_msix_rsp_q+0x79/0xf0 [qla2xxx] __handle_irq_event_percpu+0x79/0x3c0 handle_irq_event_percpu+0x70/0xf0 handle_irq_event+0x5a/0x8b handle_edge_irq+0x12c/0x310 handle_irq+0x192/0x20a do_IRQ+0x73/0x160 ret_from_intr+0x0/0x1d default_idle+0x23/0x1f0 arch_cpu_idle+0x15/0x20 default_idle_call+0x35/0x40 do_idle+0x2bb/0x2e0 cpu_startup_entry+0x1d/0x20 start_secondary+0x24d/0x2d0 secondary_startup_64+0xa4/0xb0 INITIAL USE at: lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 qla2x00_loop_resync+0xb3d/0x2690 [qla2xxx] qla2x00_do_dpc+0xcee/0xf30 [qla2xxx] kthread+0x1d2/0x1f0 ret_from_fork+0x3a/0x50 } ... key at: [<ffffffffa125f700>] __key.62804+0x0/0xfffffffffff7e900 [qla2xxx] ... acquired at: __lock_acquire+0x11ed/0x1b60 lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 klist_next+0x43/0x1d0 device_for_each_child+0x96/0x110 scsi_target_block+0x3c/0x40 [scsi_mod] fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc] qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx] qlt_unreg_sess+0x104/0x2c0 [qla2xxx] tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx] target_shutdown_sessions+0x17b/0x190 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9f/0x120 [configfs] config_item_put+0x29/0x2b [configfs] configfs_rmdir+0x3d2/0x520 [configfs] vfs_rmdir+0xb3/0x1d0 do_rmdir+0x25c/0x2d0 __x64_sys_rmdir+0x24/0x30 do_syscall_64+0x77/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe
the dependencies between the lock to be acquired and HARDIRQ-irq-unsafe lock: -> (&(&k->k_lock)->rlock){+.+.} ops: 14568 { HARDIRQ-ON-W at: lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50 SOFTIRQ-ON-W at: lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50 INITIAL USE at: lock_acquire+0xe3/0x200 _raw_spin_lock+0x32/0x50 klist_add_tail+0x33/0xb0 device_add+0x7f4/0xb60 device_create_groups_vargs+0x11c/0x150 device_create_with_groups+0x89/0xb0 vtconsole_class_init+0xb2/0x124 do_one_initcall+0xc5/0x3ce kernel_init_freeable+0x295/0x32e kernel_init+0x11/0x11b ret_from_fork+0x3a/0x50 } ... key at: [<ffffffff83f3d900>] __key.15805+0x0/0x40 ... acquired at: __lock_acquire+0x11ed/0x1b60 lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 klist_next+0x43/0x1d0 device_for_each_child+0x96/0x110 scsi_target_block+0x3c/0x40 [scsi_mod] fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc] qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx] qlt_unreg_sess+0x104/0x2c0 [qla2xxx] tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx] target_shutdown_sessions+0x17b/0x190 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9f/0x120 [configfs] config_item_put+0x29/0x2b [configfs] configfs_rmdir+0x3d2/0x520 [configfs] vfs_rmdir+0xb3/0x1d0 do_rmdir+0x25c/0x2d0 __x64_sys_rmdir+0x24/0x30 do_syscall_64+0x77/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe
stack backtrace: CPU: 7 PID: 1478 Comm: rmdir Tainted: G W 5.1.0-rc1-dbg+ #11 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x86/0xca check_usage.cold.59+0x473/0x563 check_prev_add.constprop.43+0x1f1/0x1170 __lock_acquire+0x11ed/0x1b60 lock_acquire+0xe3/0x200 _raw_spin_lock_irqsave+0x3d/0x60 klist_next+0x43/0x1d0 device_for_each_child+0x96/0x110 scsi_target_block+0x3c/0x40 [scsi_mod] fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc] qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx] qlt_unreg_sess+0x104/0x2c0 [qla2xxx] tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx] target_shutdown_sessions+0x17b/0x190 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9f/0x120 [configfs] config_item_put+0x29/0x2b [configfs] configfs_rmdir+0x3d2/0x520 [configfs] vfs_rmdir+0xb3/0x1d0 do_rmdir+0x25c/0x2d0 __x64_sys_rmdir+0x24/0x30 do_syscall_64+0x77/0x220 entry_SYSCALL_64_after_hwframe+0x49/0xbe
Cc: Himanshu Madhani hmadhani@marvell.com Cc: Giridhar Malavali gmalavali@marvell.com Signed-off-by: Bart Van Assche bvanassche@acm.org Acked-by: Himanshu Madhani hmadhani@marvell.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/qla2xxx/tcm_qla2xxx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c index 4c99f1797b489..2fcdaadd10fa5 100644 --- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c +++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c @@ -366,8 +366,9 @@ static void tcm_qla2xxx_close_session(struct se_session *se_sess)
spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags); target_sess_cmd_list_set_waiting(se_sess); - tcm_qla2xxx_put_sess(sess); spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags); + + tcm_qla2xxx_put_sess(sess); }
static u32 tcm_qla2xxx_sess_get_index(struct se_session *se_sess)