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| author | Nicholas Bellinger <nab@linux-iscsi.org> | 2011-05-20 05:19:11 +0200 |
|---|---|---|
| committer | James Bottomley <jbottomley@parallels.com> | 2011-05-24 19:00:10 +0200 |
| commit | f436677262a5b524ac87675014c6d4e8ee153029 (patch) | |
| tree | c3ab2fb111163ac52eb4999b83d3063ca4fca718 | |
| parent | [SCSI] target: Fix interrupt context bug with stats_lock and core_tmr_alloc_req (diff) | |
| download | linux-f436677262a5b524ac87675014c6d4e8ee153029.tar.xz linux-f436677262a5b524ac87675014c6d4e8ee153029.zip | |
[SCSI] target: Fix bug with task_sg chained transport_free_dev_tasks release
This patch addresses a bug in the target core release path for HW
operation where transport_free_dev_tasks() was incorrectly being called
from transport_lun_remove_cmd() while releasing a se_cmd reference and
calling struct target_core_fabric_ops->queue_data_in().
This would result in a OOPs with HW target mode when the release of
se_task->task_sg[] would happen before pci_unmap_sg() can be called in
HW target mode fabric module code. This patch addresses the issue by
moving transport_free_dev_tasks() from transport_lun_remove_cmd() into
transport_generic_free_cmd(), and adding TRANSPORT_FREE_CMD_INTR and
transport_generic_free_cmd_intr() to allow se_cmd descriptor release
to happen fromfrom within transport_processing_thread() process context
when release of se_cmd is not possible from HW interrupt context.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <jbottomley@parallels.com>
| -rw-r--r-- | drivers/target/target_core_transport.c | 13 | ||||
| -rw-r--r-- | include/target/target_core_base.h | 1 | ||||
| -rw-r--r-- | include/target/target_core_transport.h | 1 |
3 files changed, 14 insertions, 1 deletions
diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 833060e0de5e..7c87b042375a 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -762,7 +762,6 @@ static void transport_lun_remove_cmd(struct se_cmd *cmd) transport_all_task_dev_remove_state(cmd); spin_unlock_irqrestore(&T_TASK(cmd)->t_state_lock, flags); - transport_free_dev_tasks(cmd); check_lun: spin_lock_irqsave(&lun->lun_cmd_lock, flags); @@ -2058,6 +2057,13 @@ int transport_generic_handle_tmr( } EXPORT_SYMBOL(transport_generic_handle_tmr); +void transport_generic_free_cmd_intr( + struct se_cmd *cmd) +{ + transport_add_cmd_to_queue(cmd, TRANSPORT_FREE_CMD_INTR); +} +EXPORT_SYMBOL(transport_generic_free_cmd_intr); + static int transport_stop_tasks_for_cmd(struct se_cmd *cmd) { struct se_task *task, *task_tmp; @@ -5301,6 +5307,8 @@ void transport_generic_free_cmd( if (wait_for_tasks && cmd->transport_wait_for_tasks) cmd->transport_wait_for_tasks(cmd, 0, 0); + transport_free_dev_tasks(cmd); + transport_generic_remove(cmd, release_to_pool, session_reinstatement); } @@ -6136,6 +6144,9 @@ get_cmd: case TRANSPORT_REMOVE: transport_generic_remove(cmd, 1, 0); break; + case TRANSPORT_FREE_CMD_INTR: + transport_generic_free_cmd(cmd, 0, 1, 0); + break; case TRANSPORT_PROCESS_TMR: transport_generic_do_tmr(cmd); break; diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 1d3b5b2f0dbc..561ac99def5a 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -98,6 +98,7 @@ enum transport_state_table { TRANSPORT_REMOVE = 14, TRANSPORT_FREE = 15, TRANSPORT_NEW_CMD_MAP = 16, + TRANSPORT_FREE_CMD_INTR = 17, }; /* Used for struct se_cmd->se_cmd_flags */ diff --git a/include/target/target_core_transport.h b/include/target/target_core_transport.h index 59aa464f6ee2..24a1c6cb83c3 100644 --- a/include/target/target_core_transport.h +++ b/include/target/target_core_transport.h @@ -172,6 +172,7 @@ extern int transport_generic_handle_cdb_map(struct se_cmd *); extern int transport_generic_handle_data(struct se_cmd *); extern void transport_new_cmd_failure(struct se_cmd *); extern int transport_generic_handle_tmr(struct se_cmd *); +extern void transport_generic_free_cmd_intr(struct se_cmd *); extern void __transport_stop_task_timer(struct se_task *, unsigned long *); extern unsigned char transport_asciihex_to_binaryhex(unsigned char val[2]); extern int transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *, u32, |