4.7-stable review patch. If anyone has any objections, please let me know.
------------------ From: Nicholas Bellinger <[email protected]> commit 410c29dfbfdf73d0d0b5d14a21868ab038eca703 upstream. If a Simple command is sent with a failure, target_setup_cmd_from_cdb returns with TCM_UNSUPPORTED_SCSI_OPCODE or TCM_INVALID_CDB_FIELD. So in the cases where target_setup_cmd_from_cdb returns an error, we never get far enough to call target_execute_cmd to increment simple_cmds. Since simple_cmds isn't incremented, the result of the failure from target_setup_cmd_from_cdb causes transport_generic_request_failure to decrement simple_cmds, due to call to transport_complete_task_attr. With this dev->simple_cmds or dev->dev_ordered_sync is now -1, not 0. So when a subsequent command with an Ordered Task is sent, it causes a hang, since dev->simple_cmds is at -1. Tested-by: Bryant G. Ly <[email protected]> Signed-off-by: Bryant G. Ly <[email protected]> Tested-by: Michael Cyr <[email protected]> Signed-off-by: Michael Cyr <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/target/target_core_transport.c | 7 ++++++- include/target/target_core_base.h | 1 + 2 files changed, 7 insertions(+), 1 deletion(-) --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -1827,6 +1827,8 @@ static bool target_handle_task_attr(stru if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) return false; + cmd->se_cmd_flags |= SCF_TASK_ATTR_SET; + /* * Check for the existence of HEAD_OF_QUEUE, and if true return 1 * to allow the passed struct se_cmd list of tasks to the front of the list. @@ -1949,6 +1951,9 @@ static void transport_complete_task_attr if (dev->transport->transport_flags & TRANSPORT_FLAG_PASSTHROUGH) return; + if (!(cmd->se_cmd_flags & SCF_TASK_ATTR_SET)) + goto restart; + if (cmd->sam_task_attr == TCM_SIMPLE_TAG) { atomic_dec_mb(&dev->simple_cmds); dev->dev_cur_ordered_id++; @@ -1965,7 +1970,7 @@ static void transport_complete_task_attr pr_debug("Incremented dev_cur_ordered_id: %u for ORDERED\n", dev->dev_cur_ordered_id); } - +restart: target_restart_delayed_cmds(dev); } --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -142,6 +142,7 @@ enum se_cmd_flags_table { SCF_PASSTHROUGH_PROT_SG_TO_MEM_NOALLOC = 0x00200000, SCF_ACK_KREF = 0x00400000, SCF_USE_CPUID = 0x00800000, + SCF_TASK_ATTR_SET = 0x01000000, }; /*
