linux - Linux kernel source tree

Age	Commit message (Collapse)	Author
2013-06-27	target/iscsi: don't corrupt bh_count in iscsit_stop_time2retain_timer()	Joern Engel
	commit 574780fd5e6ec52bd43e0bdb777a19e4c4c6aa9c upstream. Here is a fun one. Bug seems to have been introduced by commit 140854cb, almost two years ago. I have no idea why we only started seeing it now, but we did. Rough callgraph: core_tpg_set_initiator_node_queue_depth() `-> spin_lock_irqsave(&tpg->session_lock, flags); `-> lio_tpg_shutdown_session() `-> iscsit_stop_time2retain_timer() `-> spin_unlock_bh(&se_tpg->session_lock); `-> spin_lock_bh(&se_tpg->session_lock); `-> spin_unlock_irqrestore(&tpg->session_lock, flags); core_tpg_set_initiator_node_queue_depth() used to call spin_lock_bh(), but 140854cb changed that to spin_lock_irqsave(). However, lio_tpg_shutdown_session() still claims to be called with spin_lock_bh() held, as does iscsit_stop_time2retain_timer(): * Called with spin_lock_bh(&struct se_portal_group->session_lock) held Stale documentation is mostly annoying, but in this case the dropping the lock with the _bh variant is plain wrong. It is also wrong to drop locks two functions below the lock-holder, but I will ignore that bit for now. After some more locking and unlocking we eventually hit this backtrace: ------------[ cut here ]------------ WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0xe8/0x100() Pid: 24645, comm: lio_helper.py Tainted: G O 3.6.11+ Call Trace: [<ffffffff8103e5ff>] warn_slowpath_common+0x7f/0xc0 [<ffffffffa040ae37>] ? iscsit_inc_conn_usage_count+0x37/0x50 [iscsi_target_mod] [<ffffffff8103e65a>] warn_slowpath_null+0x1a/0x20 [<ffffffff810472f8>] local_bh_enable_ip+0xe8/0x100 [<ffffffff815b8365>] _raw_spin_unlock_bh+0x15/0x20 [<ffffffffa040ae37>] iscsit_inc_conn_usage_count+0x37/0x50 [iscsi_target_mod] [<ffffffffa041149a>] iscsit_stop_session+0xfa/0x1c0 [iscsi_target_mod] [<ffffffffa0417fab>] lio_tpg_shutdown_session+0x7b/0x90 [iscsi_target_mod] [<ffffffffa033ede4>] core_tpg_set_initiator_node_queue_depth+0xe4/0x290 [target_core_mod] [<ffffffffa0409032>] iscsit_tpg_set_initiator_node_queue_depth+0x12/0x20 [iscsi_target_mod] [<ffffffffa0415c29>] lio_target_nacl_store_cmdsn_depth+0xa9/0x180 [iscsi_target_mod] [<ffffffffa0331b49>] target_fabric_nacl_base_attr_store+0x39/0x40 [target_core_mod] [<ffffffff811b857d>] configfs_write_file+0xbd/0x120 [<ffffffff81148f36>] vfs_write+0xc6/0x180 [<ffffffff81149251>] sys_write+0x51/0x90 [<ffffffff815c0969>] system_call_fastpath+0x16/0x1b ---[ end trace 3747632b9b164652 ]--- As a pure band-aid, this patch drops the _bh. Signed-off-by: Joern Engel <joern@logfs.org> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-03-10	iscsi-target: Convert to use target_put_session + sess_kref	Nicholas Bellinger
	This patch converts iscsi-target session code to use se_sess->sess_kref counting for iscsi session shutdown. The following cases include: ) last iscsit_close_connection() shutdown path to invoke close session ) iscsit_logout_post_handler_closesession() for explict logout *) iscsit_free_session() caller for explict shutdown It also moves iscsit_stop_session() call from lio_tpg_close_session() into lio_tpg_shutdown_session() TFO callbacks to invoke an explict shutdown, and also changes iscsi_check_for_session_reinstatement() login code to use se_sess->sess_kref. (v2: Make iscsit_handle_time2retain_timeout() use target_put_session) Cc: Andy Grover <agrover@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14	target: header reshuffle, part2	Christoph Hellwig
	This reorganized the headers under include/target into: - target_core_base.h stays as is with all target-wide data stuctures and defines - target_core_backend.h contains the whole interface to I/O backends - target_core_fabric.h contains the whole interface to fabric modules Except for those only the various configfs macro headers stay around. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-26	iscsi-target: Add iSCSI fabric support for target v4.1	Nicholas Bellinger
	The Linux-iSCSI.org target module is a full featured in-kernel software implementation of iSCSI target mode (RFC-3720) for the current WIP mainline target v4.1 infrastructure code for the v3.1 kernel. More information can be found here: http://linux-iscsi.org/wiki/ISCSI This includes support for: * RFC-3720 defined request / response state machines and support for all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi include/scsi/iscsi_proto.h PDU definitions * Target v4.1 compatible control plane using the generic layout in target_core_fabric_configfs.c and fabric dependent attributes within /sys/kernel/config/target/iscsi/ subdirectories. * Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS) * Support for IPv6 and IPv4 network portals in M:N mapping to TPGs * iSCSI Error Recovery Hierarchy support * Per iSCSI connection RX/TX thread pair scheduling affinity * crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto * CHAP Authentication support using libcrypto * Conversion to use internal SGl allocation with iscsit_alloc_buffs() -> transport_generic_map_mem_to_cmd() (nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit: iscsi: Use struct scsi_lun in iscsi structs instead of u8[8]) (nab: Fix 32-bit compile warnings) Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andy Grover <agrover@redhat.com> Acked-by: Roland Dreier <roland@kernel.org> Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>