4789a21880
When qeth_l2_set_mac_address() finds the card in a non-reachable state, it merely copies the new MAC address into dev->dev_addr so that __qeth_l2_set_online() can later register it with the HW. But __qeth_l2_set_online() may very well be running concurrently, so we can't trust the card state without appropriate locking: If the online sequence is past the point where it registers dev->dev_addr (but not yet in SOFTSETUP state), any address change needs to be properly programmed into the HW. Otherwise the netdevice ends up with a different MAC address than what's set in the HW, and inbound traffic is not forwarded as expected. This is most likely to occur for OSD in LPAR, where commit21b1702af1("s390/qeth: improve fallback to random MAC address") now triggers eg. systemd to immediately change the MAC when the netdevice is registered with a NET_ADDR_RANDOM address. Fixes:bcacfcbc82("s390/qeth: fix MAC address update sequence") Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.