refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds RTM_GETROUTE doit handler for mpls routes.
Input:
RTA_DST - input label
RTA_NEWDST - labels in packet for multipath selection
By default the getroute handler returns matched
nexthop label, via and oif
With RTM_F_FIB_MATCH flag, full matched route is
returned.
example (with patched iproute2):
$ip -f mpls route show
101
nexthop as to 102/103 via inet 172.16.2.2 dev virt1-2
nexthop as to 302/303 via inet 172.16.12.2 dev virt1-12
201
nexthop as to 202/203 via inet6 2001:db8:2::2 dev virt1-2
nexthop as to 402/403 via inet6 2001:db8:12::2 dev virt1-12
$ip -f mpls route get 103
RTNETLINK answers: Network is unreachable
$ip -f mpls route get 101
101 as to 102/103 via inet 172.16.2.2 dev virt1-2
$ip -f mpls route get as to 302/303 101
101 as to 302/303 via inet 172.16.12.2 dev virt1-12
$ip -f mpls route get fibmatch 103
RTNETLINK answers: Network is unreachable
$ip -f mpls route get fibmatch 101
101
nexthop as to 102/103 via inet 172.16.2.2 dev virt1-2
nexthop as to 302/303 via inet 172.16.12.2 dev virt1-12
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
current code silently ignores change of port in the request
message. This patch makes sure the port is modified and
notification is sent to userspace.
Fixes: cf6b8e1eed ("bridge: add API to notify bridge driver of learned FBD on offloaded device")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
SYN-ACK responses on a server in response to a SYN from a client
did not get the injected skb mark that was tagged on the SYN packet.
Fixes: 84f39b08d7 ("net: support marking accepting TCP sockets")
Reviewed-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Elena Reshetova says:
====================
v2 ipv4/ipv6 refcount conversions
Changes in v2:
* rebase on top of net-next
* currently by default refcount_t = atomic_t (*) and uses all
atomic standard operations unless CONFIG_REFCOUNT_FULL is enabled.
This is a compromise for the systems that are critical on
performance (such as net) and cannot accept even slight delay
on the refcounter operations.
This series, for ipv4/ipv6 network components, replaces atomic_t reference
counters with the new refcount_t type and API (see include/linux/refcount.h).
By doing this we prevent intentional or accidental
underflows or overflows that can led to use-after-free vulnerabilities.
The patches are fully independent and can be cherry-picked separately.
In order to try with refcount functionality enabled in run-time,
CONFIG_REFCOUNT_FULL must be enabled.
NOTE: automatic kernel builder for some reason doesn't like all my
network branches and regularly times out the builds on these branches.
Suggestion for "waiting a day for a good coverage" doesn't work, as
we have seen with generic network conversions. So please wait for the
full report from kernel test rebot before merging further up.
This has been compile-tested in 116 configs, but 71 timed out (including
all s390-related configs again). I am trying to see if they can fix
build coverage for me in meanwhile.
* The respective change is currently merged into -next as
"locking/refcount: Create unchecked atomic_t implementation".
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix compilation warning
qed_iwarp.c:1721:5: warning: ll2_syn_handle may be used
uninitialized in this function
Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I was trying to wrap my head around meaning of mru, and realised
that the second line of the comment defining it had somehow
ended up after the line defining cutlen, leading to much confusion.
Reorder the lines to make sense.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Last minute changes to get new hardware and firmware support for
iwlwifi and few other changes I was able to squeeze in. Also two
patches for ieee80211.h and nl80211 as Johannes is away.
Major changes:
iwlwifi
* some important fixes for 9000 HW
* support for version 30 of the FW API for 8000 and 9000 series
* a few new PCI IDs for 9000 series
* reorganization of common files
brcmfmac
* support 4-way handshake offloading for WPA/WPA2-PSK and 802.1X
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Merge tag 'wireless-drivers-next-for-davem-2017-07-03' of https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next
Kalle Valo says:
====================
wireless-drivers-next patches for 4.13
Last minute changes to get new hardware and firmware support for
iwlwifi and few other changes I was able to squeeze in. Also two
patches for ieee80211.h and nl80211 as Johannes is away.
Major changes:
iwlwifi
* some important fixes for 9000 HW
* support for version 30 of the FW API for 8000 and 9000 series
* a few new PCI IDs for 9000 series
* reorganization of common files
brcmfmac
* support 4-way handshake offloading for WPA/WPA2-PSK and 802.1X
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Some overlapping changes in the mlx5 driver.
A merge conflict resolution posted by Stephen Rothwell was used as a
guide.
Signed-off-by: David S. Miller <davem@davemloft.net>
The variable mlx4_log_num_mgm_entry_size is only called in main.c.
CC: Joe Jin <joe.jin@oracle.com>
CC: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pointer hdr in netxen_setup_minidump() is set but never used, thus
should be removed.
Signed-off-by: Christos Gkekas <chris.gekas@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jiri Benc says:
====================
vxlan, geneve: fix hlist corruption
Fix memory corruption introduced with the support of both IPv4 and IPv6
sockets in a single device. The same bug is present in VXLAN and Geneve.
====================
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's not a good idea to add the same hlist_node to two different hash lists.
This leads to various hard to debug memory corruptions.
Fixes: 8ed66f0e82 ("geneve: implement support for IPv6-based tunnels")
Cc: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's not a good idea to add the same hlist_node to two different hash lists.
This leads to various hard to debug memory corruptions.
Fixes: b1be00a6c3 ("vxlan: support both IPv4 and IPv6 sockets in a single vxlan device")
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If mlx5 is set to be built-in and mlxfw as a module, we
get a link error:
drivers/built-in.o: In function `mlx5_firmware_flash':
(.text+0x5aed72): undefined reference to `mlxfw_firmware_flash'
Since we don't want to mandate selecting mlxfw for mlx5 users, we
use the IS_REACHABLE macro to make sure that a stub is exposed
to the caller.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reported-by: Jakub Kicinski <kubakici@wp.pl>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
Misc BPF helper/verifier improvements
Miscellanous improvements I still had in my queue, it adds a new
bpf_skb_adjust_room() helper for cls_bpf, exports to fdinfo whether
tail call array owner is JITed, so iproute2 error reporting can be
improved on that regard, a small cleanup and extension to trace
printk, two verifier patches, one to make the code around narrower
ctx access a bit more straight forward and one to allow for imm += x
operations, that we've seen LLVM generating and the verifier currently
rejecting. We've included the patch 6 given it's rather small and
we ran into it from LLVM side, it would be great if it could be
queued for stable as well after the merge window. Last but not least,
test cases are added also related to imm alu improvement.
Thanks a lot!
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Add couple of verifier test cases for x|imm += pkt_ptr, including the
imm += x extension.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the verifier does not track imm across alu operations when
the source register is of unknown type. This adds additional pattern
matching to catch this and track imm. We've seen LLVM generating this
pattern while working on cilium.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, bpf_trace_printk does not support common formatting
symbol '%i' however vsprintf does and is what eventually gets
called by bpf helper. If users are used to '%i' and currently
make use of it, then bpf_trace_printk will just return with
error without dumping anything to the trace pipe, so just add
support for '%i' to the helper.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We do export through fdinfo already whether a prog is JITed or not,
given a program load can fail in case of either prog or tail call map
has JITed property, but neither both are JITed or not JITed, we can
facilitate error reporting in loaders like iproute2 through exporting
owner_jited of tail call map. We already do export owner_prog_type
through this facility, so parser can pick up both for comparison.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This work tries to make the semantics and code around the
narrower ctx access a bit easier to follow. Right now
everything is done inside the .is_valid_access(). Offset
matching is done differently for read/write types, meaning
writes don't support narrower access and thus matching only
on offsetof(struct foo, bar) is enough whereas for read
case that supports narrower access we must check for
offsetof(struct foo, bar) + offsetof(struct foo, bar) +
sizeof(<bar>) - 1 for each of the cases. For read cases of
individual members that don't support narrower access (like
packet pointers or skb->cb[] case which has its own narrow
access logic), we check as usual only offsetof(struct foo,
bar) like in write case. Then, for the case where narrower
access is allowed, we also need to set the aux info for the
access. Meaning, ctx_field_size and converted_op_size have
to be set. First is the original field size e.g. sizeof(<bar>)
as in above example from the user facing ctx, and latter
one is the target size after actual rewrite happened, thus
for the kernel facing ctx. Also here we need the range match
and we need to keep track changing convert_ctx_access() and
converted_op_size from is_valid_access() as both are not at
the same location.
We can simplify the code a bit: check_ctx_access() becomes
simpler in that we only store ctx_field_size as a meta data
and later in convert_ctx_accesses() we fetch the target_size
right from the location where we do convert. Should the verifier
be misconfigured we do reject for BPF_WRITE cases or target_size
that are not provided. For the subsystems, we always work on
ranges in is_valid_access() and add small helpers for ranges
and narrow access, convert_ctx_accesses() sets target_size
for the relevant instruction.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Cc: Yonghong Song <yhs@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This work adds a helper that can be used to adjust net room of an
skb. The helper is generic and can be further extended in future.
Main use case is for having a programmatic way to add/remove room to
v4/v6 header options along with cls_bpf on egress and ingress hook
of the data path. It reuses most of the infrastructure that we added
for the bpf_skb_change_type() helper which can be used in nat64
translations. Similarly, the helper only takes care of adjusting the
room so that related data is populated and csum adapted out of the
BPF program using it.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a small skb_mac_header_len() helper similarly as the
skb_network_header_len() we have and replace open coded
places in BPF's bpf_skb_change_proto() helper. Will also
be used in upcoming work.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The HP lt4132 LTE/HSPA+ 4G Module (03f0:a31d) is a rebranded Huawei
ME906s-158 device. It, like the ME906s-158, requires the "NDP to end"
quirk for correct operation.
Signed-off-by: Tore Anderson <tore@fud.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the IPVLAN documentation there is an example command line where the
master and slave interface names are inverted.
Fix the command line and also add the optional `name' keyword to better
describe what the command is doing.
v2: added commit message
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit a985343ba9 ("vxlan: refactor verification and application of
configuration") modified vxlan device creation, and replaced the
assignment of vxlan->net to src_net with dev_net(netdev) in ->setup().
But dev_net(netdev) is not the same as src_net. At the time ->setup()
is called, dev_net hasn't been set yet, so we end up creating the
socket for the vxlan device in init_net.
Fix this by bringing back the assignment of vxlan->net during device
creation.
Fixes: a985343ba9 ("vxlan: refactor verification and application of configuration")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lin Yun Sheng says:
====================
Add loopback support in phy_driver and hns ethtool fix
This Patch Set add set_loopback in phy_driver and use it to setup loopback
when doing ethtool phy self_test.
Patch V8:
Respin the Patch based on net-next
Patch V7:
1. Add comment why resume the phy in hns_nic_config_phy_loopback.
2. Fix a typo error in patch description.
Patch V6:
Fix Or'ing error code in __lb_setup.
Patch V5:
Removing non loopback related code change.
Patch V4:
1. Remove c45 checking
2. Add -ENOTSUPP when function pointer is null,
take mutex in phy_loopback.
Patch V3:
Calling phy_loopback enable and disable in pair in hns mac driver.
Patch V2:
1. Add phy_loopback in phy_device.c.
2. Do error checking and do the read and write once in
genphy_loopback.
3. Remove gen10g_loopback in phy_device.c.
Patch V1:
Initial Submit
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use function set_loopback in phy_driver to setup phy loopback
when doing ethtool self test.
Signed-off-by: Lin Yun Sheng <linyunsheng@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch add set_loopback in phy_driver, which is used by MAC
driver to enable or disable phy loopback. it also add a generic
genphy_loopback function, which use BMCR loopback bit to enable
or disable loopback.
Signed-off-by: Lin Yun Sheng <linyunsheng@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, when the link for $DEV is down, this command succeeds but the
address is removed immediately by DAD (1):
ip addr add 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800
In the same situation, this will succeed and not remove the address (2):
ip addr add 1111::12/64 dev $DEV
ip addr change 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800
The comment in addrconf_dad_begin() when !IF_READY makes it look like
this is the intended behavior, but doesn't explain why:
* If the device is not ready:
* - keep it tentative if it is a permanent address.
* - otherwise, kill it.
We clearly cannot prevent userspace from doing (2), but we can make (1)
work consistently with (2).
addrconf_dad_stop() is only called in two cases: if DAD failed, or to
skip DAD when the link is down. In that second case, the fix is to avoid
deleting the address, like we already do for permanent addresses.
Fixes: 3c21edbd11 ("[IPV6]: Defer IPv6 device initialization until the link becomes ready.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The CDC-NCM driver can require large amounts of memory to create
skb's and this can be a problem when the memory becomes fragmented.
This especially affects embedded systems that have constrained
resources but wish to maximise the throughput of CDC-NCM with 16KiB
NTB's.
The issue is after running for a while the kernel memory can become
fragmented and it needs compacting.
If the NTB allocation is needed before the memory has been compacted
the atomic allocation can fail which can cause increased latency,
large re-transmissions or disconnections depending upon the data
being transmitted at the time.
This situation occurs for less than a second until the kernel has
compacted the memory but the failed devices can take a lot longer to
recover from the failed TX packets.
To ease this temporary situation I modified the CDC-NCM TX path to
temporarily switch into a reduced memory mode which allocates an NTB
that will fit into a USB_CDC_NCM_NTB_MIN_OUT_SIZE (default 2048 Bytes)
sized memory block and only transmit NTB's with a single network frame
until the memory situation is resolved.
Each time this issue occurs we wait for an increasing number of
reduced size allocations before requesting a full size one to not
put additional pressure on a low memory system.
Once the memory is compacted the CDC-NCM data can resume transmitting
at the normal tx_max rate once again.
Signed-off-by: Jim Baxter <jim_baxter@mentor.com>
Reviewed-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
