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The patch adds support for erspan version 2. Not all features are
supported in this patch. The SGT (security group tag), GRA (timestamp
granularity), FT (frame type) are set to fixed value. Only hardware
ID and direction are configurable. Optional subheader is also not
supported.
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The patch refactors the existing erspan implementation in order
to support erspan version 2, which has additional metadata. So, in
stead of having one 'struct erspanhdr' holding erspan version 1,
breaks it into 'struct erspan_base_hdr' and 'struct erspan_metadata'.
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Jakub Kicinski says:
====================
nfp: ethtool flash updates
Dirk says:
This series adds the ability to update the control FW with ethtool.
It should be noted that the locking scheme here is to release the RTNL
lock before the flashing operation and to take it again afterwards to
ensure consistent state from the core code point of view. In this time,
we take a reference to the device to prevent the device being freed
while its being flashed.
This provides protection for the device being flashed while at the same
time not holding up any networking related functions which would
otherwise be locked out due to RTNL being held.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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Firmware flashing takes around 60s (specified to not take more than
70s). Prevent hogging the RTNL lock in this time and make use of the
longer timeout for the NSP command. The timeout is set to 2.5 * 70
seconds.
We only allow flashing the firmware from reprs or PF netdevs. VFs do not
have an app reference.
Signed-off-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The firmware flashing NSP operation takes longer to execute than the
current default timeout. We need a mechanism to set a longer timeout for
some commands. This patch adds the infrastructure to this.
The default timeout is still 30 seconds.
Signed-off-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Mahesh Bandewar says:
====================
ipvlan: packet scrub
While crossing namespace boundary IPvlan aggressively scrubs packets.
This is creating problems. First thing is that scrubbing changes the
packet type in skb meta-data to PACKET_HOST. This causes erroneous
packet delivery when dev_forward_skb() has already marked the packet
type as OTHER_HOST.
On the egress side scrubbing just before calling dev_queue_xmit()
creates another set of problems. Scrubbing remove skb->sk so the
prio update gets missed and more seriously, socket back-pressure
fails making TSQ not function correctly.
The first patch in the series just reverts the earlier change which
was adding a mac-check, but that is unnecessary if packet_type that
dev_forward_skb() has set is honored. The second path removes two of
the scrubs which are causing problems described above.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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IPvlan currently scrubs packets at every location where packets may be
crossing namespace boundary. Though this is desirable, currently IPvlan
does it more than necessary. e.g. packets that are going to take
dev_forward_skb() path will get scrubbed so no point in scrubbing them
before forwarding. Another side-effect of scrubbing is that pkt-type gets
set to PACKET_HOST which overrides what was already been set by the
earlier path making erroneous delivery of the packets.
Also scrubbing packets just before calling dev_queue_xmit() has detrimental
effects since packets lose skb->sk and because of that miss prio updates,
incorrect socket back-pressure and would even break TSQ.
Fixes: b93dd49c1a35 ('ipvlan: Scrub skb before crossing the namespace boundary')
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This reverts commit 92ff42645028fa6f9b8aa767718457b9264316b4.
Even though the check added is not that taxing, it's not really needed.
First of all this will be per packet cost and second thing is that the
eth_type_trans() already does this correctly. The excessive scrubbing
in IPvlan was changing the pkt-type skb metadata of the packet which
made it necessary to re-check the mac. The subsequent patch in this
series removes the faulty packet-scrub.
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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skb_complete_tx_timestamp must ingest the skb it is passed. Call
kfree_skb if the skb cannot be enqueued.
Fixes: b245be1f4db1 ("net-timestamp: no-payload only sysctl")
Fixes: 9ac25fc06375 ("net: fix socket refcounting in skb_complete_tx_timestamp()")
Reported-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Julian Wiedmann says:
====================
s390/qeth: fixes 2017-12-13
some more patches for 4.15, that fix multiple issues with IP Takeover
configuration in qeth.
Please queue them up for stable kernels as well (4.9 and newer).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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Any modification to the takeover IP-ranges requires that we re-evaluate
which IP addresses are takeover-eligible. Otherwise we might do takeover
for some addresses when we no longer should, or vice-versa.
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Modifying the flags of an IP addr object needs to be protected against
eg. concurrent removal of the same object from the IP table.
Fixes: 5f78e29ceebf ("qeth: optimize IP handling in rx_mode callback")
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When takeover is switched off, current code clears the 'TAKEOVER' flag on
all IPs. But the flag is also used for RXIP addresses, and those should
not be affected by the takeover mode.
Fix the behaviour by consistenly applying takover logic to NORMAL
addresses only.
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Just as for an explicit enable/disable, toggling the takeover mode also
requires that the IP addresses get updated. Otherwise all IPs that were
added to the table before the mode-toggle, get registered with the old
settings.
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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According to the kernel-doc documentation, externally visible functions
should be documented. This refers to all all non-static function which can
(and will) be used by functions in other sources files.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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Externally visible functions should be documented with kernel-doc. This
usually refers to non-static functions but also static inline files in
headers are visible in other files and should therefore be documented.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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All enums in types.h are already documented. But some other headers
still have private enums which also should be documented.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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All structs in types.h are already documented. But some other headers
still have private structs which also should be documented.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The correct syntax to create references in kernel-doc to a struct member is
not "struct_name::member"" but "&struct_name->member" or
"&struct_name.member". The correct syntax is required to get the correct
cross-referencing in the reStructuredText text output.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The inline kernel-doc comments make it easier to keep changes to the
struct/enum synchronized with the documentation of the it. And it makes it
easier for larger structures like struct batadv_priv to read the
documentation inside the code.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The documentation describing kernel-doc comments for functions ("How to
format kernel-doc comments") uses parentheses at the end of the function
name. Using this format allows to use a consistent style when adding
documentation to a function and when referencing this function in a
different kernel-doc section.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The linux/wait.h include was removed with commit 421d988b2c08 ("batman-adv:
Consolidate logging related functions"). The previously required (but not
unused) linux/sched.h include can also be dropped now.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The linux/kobject.h provides the kobject_* function declarations and should
therefore be included directly before they are used.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The linux/net.h provides the net_ratelimited_function. It should
therefore be included directly before it is used.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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commit bc6245e5efd7 ("bug: split BUILD_BUG stuff out into
<linux/build_bug.h>") added a new header for BUILD_BUG_ON. It should
therefore be included instead of linux/bug.h
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The linux/gfp.h provides the GFP_ATOMIC and GFP_KERNEL define. It should
therefore be included instead of linux/fs.h.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The ISC license is considered as not recommended in "Linux kernel licensing
rules". It should only be used for existing code or for importing code from
a different project with that license.
But the kernel still has the similar sounding MIT/Expat license under the
preferred licenses. Switching to this license for this relatively new file
should therefore allow batman-adv to better follow the new licensing rules.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Acked-by: Antonio Quartulli <a@unstable.cc>
Acked-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The last remaining file without license notice and/or SPDX license
identifier under net/batman-adv/ is the Kconfig. It should have been
licensed under the same conditions as the rest of batman-adv and the
Makefile which uses the CONFIG_* variables from Kconfig.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The "Linux licensing rules" require that also the restructuredText files
are marked with the appropriate SPDX license identifier.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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The "Linux kernel licensing rules" require that each file has a SPDX
license identifier as first line (and sometimes as second line).
The FSFE REUSE practices [1] would also require the same tags but have no
restrictions on the placement in the source file. Using the "Linux kernel
licensing rules" is therefore also fulfilling the FSFE REUSE practices
requirements at the same time.
[1] https://reuse.software/practices/
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
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Commit 9de52a755cfb6da5 ("arm64: fpsimd: Fix failure to restore FPSIMD
state after signals") fixed an issue reported in our FPSIMD signal
restore code but inadvertently introduced another issue which tends to
manifest as random SEGVs in userspace.
The problem is that when we copy the struct fpsimd_state from the kernel
stack (populated from the signal frame) into the struct held in the
current thread_struct, we blindly copy uninitialised stack into the
"cpu" field, which means that context-switching of the FP registers is
no longer reliable.
This patch fixes the problem by copying only the user_fpsimd member of
struct fpsimd_state. We should really rework the function prototypes
to take struct user_fpsimd_state * instead, but let's just get this
fixed for now.
Cc: Dave Martin <Dave.Martin@arm.com>
Fixes: 9de52a755cfb6da5 ("arm64: fpsimd: Fix failure to restore FPSIMD state after signals")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next
Steffen Klassert says:
====================
pull request (net-next): ipsec-next 2017-12-15
1) Currently we can add or update socket policies, but
not clear them. Support clearing of socket policies
too. From Lorenzo Colitti.
2) Add documentation for the xfrm device offload api.
From Shannon Nelson.
3) Fix IPsec extended sequence numbers (ESN) for
IPsec offloading. From Yossef Efraim.
4) xfrm_dev_state_add function returns success even for
unsupported options, fix this to fail in such cases.
From Yossef Efraim.
5) Remove a redundant xfrm_state assignment.
From Aviv Heller.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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Simon Wunderlich says:
====================
Here are some batman-adv bugfixes:
- Initialize the fragment headers, by Sven Eckelmann
- Fix a NULL check in BATMAN V, by Sven Eckelmann
- Fix kernel doc for the time_setup() change, by Sven Eckelmann
- Use the right lock in BATMAN IV OGM Update, by Sven Eckelmann
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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Update the compatible string and Device Tree binding document for
7278B0.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Salil Mehta says:
====================
Hisilicon Network Subsystem 3 VF Ethernet Driver
This patch-set contains the support of the HNS3 (Hisilicon Network Subsystem 3)
Virtual Function Ethernet driver for hip08 family of SoCs. The Physical Function
driver is already part of the Linux mainline.
This VF driver has its Hardware Compatibility Layer and has commom/unified ENET
layer/client/ethtool code with the PF driver. It also has support of mailbox to
communicate with the HNS3 PF driver. The basic architecture of VF driver is
derivative of the PF driver. Just like PF driver, this driver is also PCI
Express based.
This driver is the ongoing development work and HNS3 VF Ethernet driver would be
incrementally enhanced with more new features.
High Level Architecture:
[ Ethtool ]
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[ Ethernet Client ] ... [ RoCE Client ]
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[ HNAE Device ] |________
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--------------------------------------------- |
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[ HNAE3 Framework (Register/unregister) ] |
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--------------------------------------------- |
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[ VF HCLGE Layer ] |
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| [ VF Mailbox (To PF via IMP) ] |
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[ IMP command Interface ] [ IMP command Interface ]
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(A B O V E R U N S O N G U E S T S Y S T E M)
-------------------------------------------------------------
Q E M U / V F I O / K V M (on Host System)
-------------------------------------------------------------
HIP08 H A R D W A R E (limited to VF by SMMU)
[ IMP/Mgmt Processor (hardware common to system/cmd based) ]
Fig 1. HNS3 Virtual Function Driver
[ dcbnl ] [ Ethtool ]
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[ Ethernet Client ] [ ODP/UIO Client ] . . .[ RoCE Client ]
|_____________________| |
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[ HNAE Device ] | |
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--------------------------------------------- |
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[ HNAE3 Framework (Register/unregister) ] |
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--------------------------------------------- |
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[ HCLGE Layer ] |
________________|_________________ |
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[ DCB ] | | |
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[ Scheduler/Shaper ] [ MDIO ] [ PF Mailbox ] |
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|________________|_________________| |
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[ IMP command Interface ] [ IMP command Interface ]
----------------------------------------------------------------
HIP08 H A R D W A R E
[ IMP/Mgmt Processor (hardware common to system/cmd based) ]
Fig 2. Existing HNS3 PF Driver (added with mailbox)
Change Log Summary:
Patch V4: Addressed SPDX related comment by Philippe Ombredanne
Patch V3: Addressed SPDX change requested by Philippe Ombredanne
Patch V2: 1. Addressed some comments by David Miller.
2. Addressed some internal comments on various patches
Patch V1: Initial Submit
====================
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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All PF mailbox events are conveyed through a common interrupt
(vector 0). This interrupt vector is shared by reset and mailbox.
This patch adds the handling of mailbox interrupt event and its
deferred processing in context to a separate mailbox task.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch is required to support ring-vector binding and reset
of TQPs requested by the VF driver to the PF driver. Mailbox
handler is added with corresponding VF commands/messages to
handle the request.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Command queue provides the provision of Mailbox command which
can be used for communication between PF and VF. PF handles
messages from various VFs for fetching various information like,
queue, vlan, link status related etc. It also handles the request
from various VFs to perform certain privileged operations.
This patch adds the support of a message handler for handling
such various command requests from VF.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Most of the NAPI handling interface, skb buffer management,
management of the RX/TX descriptors, ethool interface etc.
has quite a bit of code which is common to VF and PF driver.
This patch makes the exisitng PF's HNS3 ENET driver as the
common ENET driver for both Virtual & Physical Function. This
will help in reduction of redundancy and better management of
code.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch introduces the new Makefiles and updates existing
Makefiles required to build the HNS3 Virtual Function driver.
This also updates the Kconfig for introduction of new menuconfig
entries related to VF driver.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch adds the support of hardware compatibiltiy layer to the
HNS3 VF Driver. This layer implements various {set|get} operations
over MAC address for a virtual port, RSS related configuration,
fetches the link status info from PF, does various VLAN related
configuration over the virtual port, queries the statistics from
the hardware etc.
This layer can directly interact with hardware through the
IMP(Integrated Mangement Processor) interface or can use mailbox
to interact with the PF driver.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch adds the support of the mailbox to the VF driver. The
mailbox shall be used as an interface to communicate with the
PF driver for various purposes like {set|get} MAC related
operations, reset, link status etc. The mailbox supports both
synchronous and asynchronous command send to PF driver.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch adds support of command interface for communication with
the IMP(Integrated Management Processor) for HNS3 Virtual Function
Driver.
Each VF has support of CQP(Command Queue Pair) ring interface.
Each CQP consis of send queue CSQ and receive queue CRQ.
There are various commands a VF may support, like to query frimware
version, TQP management, statistics, interrupt related, mailbox etc.
This also contains code to initialize the command queue, manage the
command queue descriptors and Rx/Tx protocol with the command processor
in the form of various commands/results and acknowledgements.
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Learning is currently enabled for ports which are OVS slaves -
even though OVS doesn't need this indication.
Since we're not associating a fid with the port, HW would continuously
notify driver of learned [& aged] MACs which would be logged as errors.
Fixes: 2b94e58df58c ("mlxsw: spectrum: Allow ports to work under OVS master")
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Sean Wang says:
====================
add VLAN support to DSA MT7530
Changes sicne v2:
update to the latest code base from net-next and fix up all building
errors with -Werror.
Changes since v1:
- fix up the typo
- prefer ordering declarations longest to shortest
- update that vlan_prepare callback should not change any state
- use lower case letter for function naming
The patchset extends DSA MT7530 to VLAN support through filling required
callbacks in patch 1 and merging the special tag with VLAN tag in patch 2
for allowing that the hardware can handle these packets with VID from the
CPU port.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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I work for MediaTek and maintain SoC targeting to home gateway and
also will keep extending and testing the function from MediaTek
switch.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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In order to let MT7530 switch can recognize well those egress packets
having both special tag and VLAN tag, the information about the special
tag should be carried on the existing VLAN tag. On the other hand, it's
unnecessary for extra handling for ingress packets when VLAN tag is
present since it is able to put the VLAN tag after the special tag and
then follow the existing way to parse.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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MT7530 can treat each port as either VLAN-unaware port or VLAN-aware port
through the implementation of port matrix mode or port security mode on
the ingress port, respectively. On one hand, Each port has been acting as
the VLAN-unaware one whenever the device is created in the initial or
certain port joins or leaves into/from the bridge at the runtime. On the
other hand, the patch just filling the required callbacks for VLAN
operations is achieved via extending the port to be into port security
mode when the port is configured as VLAN-aware port. Which mode can make
the port be able to recognize VID from incoming packets and look up VLAN
table to validate and judge which port it should be going to. And the
range for VID from 1 to 4094 is valid for the hardware.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Daniel Wagner reported a crash on the BeagleBone Black SoC.
This is a single CPU architecture, and does not have a functional
arch_send_call_function_single_ipi() implementation which can crash
the kernel if that is called.
As it only has one CPU, it shouldn't be called, but if the kernel is
compiled for SMP, the push/pull RT scheduling logic now calls it for
irq_work if the one CPU is overloaded, it can use that function to call
itself and crash the kernel.
Ideally, we should disable the SCHED_FEAT(RT_PUSH_IPI) if the system
only has a single CPU. But SCHED_FEAT is a constant if sched debugging
is turned off. Another fix can also be used, and this should also help
with normal SMP machines. That is, do not initiate the pull code if
there's only one RT overloaded CPU, and that CPU happens to be the
current CPU that is scheduling in a lower priority task.
Even on a system with many CPUs, if there's many RT tasks waiting to
run on a single CPU, and that CPU schedules in another RT task of lower
priority, it will initiate the PULL logic in case there's a higher
priority RT task on another CPU that is waiting to run. But if there is
no other CPU with waiting RT tasks, it will initiate the RT pull logic
on itself (as it still has RT tasks waiting to run). This is a wasted
effort.
Not only does this help with SMP code where the current CPU is the only
one with RT overloaded tasks, it should also solve the issue that
Daniel encountered, because it will prevent the PULL logic from
executing, as there's only one CPU on the system, and the check added
here will cause it to exit the RT pull code.
Reported-by: Daniel Wagner <wagi@monom.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: 4bdced5c9 ("sched/rt: Simplify the IPI based RT balancing logic")
Link: http://lkml.kernel.org/r/20171202130454.4cbbfe8d@vmware.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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