linux-dev/drivers/s390/net/qeth_l2_sys.c, branch linus/master

s390/qeth: use dev->groups for common sysfs attributes

2020-12-07T14:55:21Z

All qeth devices have a minimum set of sysfs attributes, and non-OSN devices share a group of additional attributes. Depending on whether the device is forced to use a specific discipline, the device_type then specifies further attributes. Shift the common attributes into dev->groups, so that the device_type only contains the discipline-specific attributes. This avoids exposing the common attributes to the disciplines, and nicely cleans up our sysfs code. While replacing the qeth_l*_*_device_attributes() helpers, switch from sysfs_*_groups() to the more generic device_*_groups(). Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller

s390/qeth: Reset address notification in case of buffer overflow

2020-09-15T20:21:47Z

In case hardware sends more device-to-bridge-address-change notfications than the qeth-l2 driver can handle, the hardware will send an overflow event and then stop sending any events. It expects software to flush its FDB and start over again. Re-enabling address-change-notification will report all current addresses. In order to re-enable address-change-notification this patch defines the functions qeth_l2_dev2br_an_set() and qeth_l2_dev2br_an_set_cb to enable or disable dev-to-bridge-address-notification. A following patch will use the learning_sync bridgeport flag to trigger enabling or disabling of address-change-notification, so we define priv->brport_features to store the current setting. BRIDGE_INFO and ADDR_INFO functionality are mutually exclusive, whereas ADDR_INFO and qeth_l2_vnicc* can be used together. Alternative implementations to handle buffer overflow: Just re-enabling notification and adding all newly reported addresses would cover any lost 'add' events, but not the lost 'delete' events. Then these invalid addresses would stay in the bridge FDB as long as the device exists. Setting the net device down and up, would be an alternative, but is a bit drastic. If the net device has many secondary addresses this will create many delete/add events at its peers which could de-stabilize the network segment. Signed-off-by: Alexandra Winter Reviewed-by: Julian Wiedmann Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller

s390/qeth: strictly order bridge address events

2020-08-27T14:42:04Z

The current code for bridge address events has two shortcomings in its control sequence: 1. after disabling address events via PNSO, we don't flush the remaining events from the event_wq. So if the feature is re-enabled fast enough, stale events could leak over. 2. PNSO and the events' arrival via the READ ccw device are unordered. So even if we flushed the workqueue, it's difficult to say whether the READ device might produce more events onto the workqueue afterwards. Fix this by 1. explicitly fencing off the events when we no longer care, in the READ device's event handler. This ensures that once we flush the workqueue, it doesn't get additional address events. 2. Flush the workqueue after disabling the events & fencing them off. As the code that triggers the flush will typically hold the sbp_lock, we need to rework the worker code to avoid a deadlock here in case of a 'notifications-stopped' event. In case of lock contention, requeue such an event with a delay. We'll eventually aquire the lock, or spot that the feature has been disabled and the event can thus be discarded. This leaves the theoretical race that a stale event could arrive _after_ we re-enabled ourselves to receive events again. Such an event would be impossible to distinguish from a 'good' event, nothing we can do about it. Signed-off-by: Julian Wiedmann Reviewed-by: Alexandra Winter Signed-off-by: David S. Miller

s390/qeth: shift some bridgeport code around

2020-01-26T14:20:32Z

qeth_l2_setup_bridgeport_attrs() is entirely unrelated to sysfs functionality, move it where it belongs. While at it merge all the bridgeport-specific code in the set-online path together. Signed-off-by: Julian Wiedmann Reviewed-by: Alexandra Winter Signed-off-by: David S. Miller

s390/qeth: fix promiscuous mode after reset

2019-12-21T05:00:27Z

When managing the promiscuous mode during an RX modeset, qeth caches the current HW state to avoid repeated programming of the same state on each modeset. But while tearing down a device, we forget to clear the cached state. So when the device is later set online again, the initial RX modeset doesn't program the promiscuous mode since we believe it is already enabled. Fix this by clearing the cached state in the tear-down path. Note that for the SBP variant of promiscuous mode, this accidentally works right now because we unconditionally restore the SBP role while re-initializing. Fixes: 4a71df50047f ("qeth: new qeth device driver") Signed-off-by: Julian Wiedmann Reviewed-by: Alexandra Winter Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2019-11-23T00:27:24Z

Minor conflict in drivers/s390/net/qeth_l2_main.c, kept the lock from commit c8183f548902 ("s390/qeth: fix potential deadlock on workqueue flush"), removed the code which was removed by commit 9897d583b015 ("s390/qeth: consolidate some duplicated HW cmd code"). Signed-off-by: Jakub Kicinski

s390/qeth: fix potential deadlock on workqueue flush

2019-11-20T20:29:47Z

The L2 bridgeport code uses the coarse 'conf_mutex' for guarding access to its configuration state. This can result in a deadlock when qeth_l2_stop_card() - called under the conf_mutex - blocks on flush_workqueue() to wait for the completion of pending bridgeport workers. Such workers would also need to aquire the conf_mutex, stalling indefinitely. Introduce a lock that specifically guards the bridgeport configuration, so that the workers no longer need the conf_mutex. Wrapping qeth_l2_promisc_to_bridge() in this fine-grained lock then also fixes a theoretical race against a concurrent qeth_bridge_port_role_store() operation. Fixes: c0a2e4d10d93 ("s390/qeth: conclude all event processing before offlining a card") Signed-off-by: Julian Wiedmann Reviewed-by: Alexandra Winter Signed-off-by: David S. Miller

s390/qeth: don't check drvdata in sysfs code

2019-11-15T02:16:51Z

Given the way how the sysfs attributes are registered / unregistered, the show/store helpers will never be called with a NULL drvdata. Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-11-04T00:26:51Z

Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman