4e108d4f28
iscsi_target_sk_data_ready() could be invoked indirectly by
iscsi_target_do_login_rx() from the workqueue like this:
iscsi_target_do_login_rx()
iscsi_target_do_login()
iscsi_target_do_tx_login_io()
iscsit_put_login_tx()
iscsi_login_tx_data()
tx_data()
sock_sendmsg_nosec()
tcp_sendmsg()
release_sock()
sk_backlog_rcv()
tcp_v4_do_rcv()
tcp_data_ready()
iscsi_target_sk_data_ready()
At that time LOGIN_FLAGS_READ_ACTIVE is not cleared and
iscsi_target_sk_data_ready will not read data from the socket. Some iscsi
initiators (libiscsi) will wait forever for a reply.
LOGIN_FLAGS_READ_ACTIVE should be cleared early just after doing the
receive and before writing to the socket in iscsi_target_do_login_rx.
Unfortunately, LOGIN_FLAGS_READ_ACTIVE is also used by sk_state_change to
do login cleanup if a socket was closed at login time. It is supposed to be
cleared after the login PDU is successfully processed and replied.
Introduce another flag, LOGIN_FLAGS_WRITE_ACTIVE, to cover the transmit
part.
Link: https://lore.kernel.org/r/20200716100212.4237-2-houpu@bytedance.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Hou Pu <houpu@bytedance.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.