Daniel Borkmann says:
====================
pull-request: bpf-next 2018-03-21
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Add a BPF hook for sendmsg and sendfile by reusing the ULP infrastructure
and sockmap. Three helpers are added along with this, bpf_msg_apply_bytes(),
bpf_msg_cork_bytes(), and bpf_msg_pull_data(). The first is used to tell
for how many bytes the verdict should be applied to, the second to tell
that x bytes need to be queued first to retrigger the BPF program for a
verdict, and the third helper is mainly for the sendfile case to pull in
data for making it private for reading and/or writing, from John.
2) Improve address to symbol resolution of user stack traces in BPF stackmap.
Currently, the latter stores the address for each entry in the call trace,
however to map these addresses to user space files, it is necessary to
maintain the mapping from these virtual addresses to symbols in the binary
which is not practical for system-wide profiling. Instead, this option for
the stackmap rather stores the ELF build id and offset for the call trace
entries, from Song.
3) Add support that allows BPF programs attached to perf events to read the
address values recorded with the perf events. They are requested through
PERF_SAMPLE_ADDR via perf_event_open(). Main motivation behind it is to
support building memory or lock access profiling and tracing tools with
the help of BPF, from Teng.
4) Several improvements to the tools/bpf/ Makefiles. The 'make bpf' in the
tools directory does not provide the standard quiet output except for
bpftool and it also does not respect specifying a build output directory.
'make bpf_install' command neither respects specified destination nor
prefix, all from Jiri. In addition, Jakub fixes several other minor issues
in the Makefiles on top of that, e.g. fixing dependency paths, phony
targets and more.
5) Various doc updates e.g. add a comment for BPF fs about reserved names
to make the dentry lookup from there a bit more obvious, and a comment
to the bpf_devel_QA file in order to explain the diff between native
and bpf target clang usage with regards to pointer size, from Quentin
and Daniel.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This implements a BPF ULP layer to allow policy enforcement and
monitoring at the socket layer. In order to support this a new
program type BPF_PROG_TYPE_SK_MSG is used to run the policy at
the sendmsg/sendpage hook. To attach the policy to sockets a
sockmap is used with a new program attach type BPF_SK_MSG_VERDICT.
Similar to previous sockmap usages when a sock is added to a
sockmap, via a map update, if the map contains a BPF_SK_MSG_VERDICT
program type attached then the BPF ULP layer is created on the
socket and the attached BPF_PROG_TYPE_SK_MSG program is run for
every msg in sendmsg case and page/offset in sendpage case.
BPF_PROG_TYPE_SK_MSG Semantics/API:
BPF_PROG_TYPE_SK_MSG supports only two return codes SK_PASS and
SK_DROP. Returning SK_DROP free's the copied data in the sendmsg
case and in the sendpage case leaves the data untouched. Both cases
return -EACESS to the user. Returning SK_PASS will allow the msg to
be sent.
In the sendmsg case data is copied into kernel space buffers before
running the BPF program. The kernel space buffers are stored in a
scatterlist object where each element is a kernel memory buffer.
Some effort is made to coalesce data from the sendmsg call here.
For example a sendmsg call with many one byte iov entries will
likely be pushed into a single entry. The BPF program is run with
data pointers (start/end) pointing to the first sg element.
In the sendpage case data is not copied. We opt not to copy the
data by default here, because the BPF infrastructure does not
know what bytes will be needed nor when they will be needed. So
copying all bytes may be wasteful. Because of this the initial
start/end data pointers are (0,0). Meaning no data can be read or
written. This avoids reading data that may be modified by the
user. A new helper is added later in this series if reading and
writing the data is needed. The helper call will do a copy by
default so that the page is exclusively owned by the BPF call.
The verdict from the BPF_PROG_TYPE_SK_MSG applies to the entire msg
in the sendmsg() case and the entire page/offset in the sendpage case.
This avoids ambiguity on how to handle mixed return codes in the
sendmsg case. Again a helper is added later in the series if
a verdict needs to apply to multiple system calls and/or only
a subpart of the currently being processed message.
The helper msg_redirect_map() can be used to select the socket to
send the data on. This is used similar to existing redirect use
cases. This allows policy to redirect msgs.
Pseudo code simple example:
The basic logic to attach a program to a socket is as follows,
// load the programs
bpf_prog_load(SOCKMAP_TCP_MSG_PROG, BPF_PROG_TYPE_SK_MSG,
&obj, &msg_prog);
// lookup the sockmap
bpf_map_msg = bpf_object__find_map_by_name(obj, "my_sock_map");
// get fd for sockmap
map_fd_msg = bpf_map__fd(bpf_map_msg);
// attach program to sockmap
bpf_prog_attach(msg_prog, map_fd_msg, BPF_SK_MSG_VERDICT, 0);
Adding sockets to the map is done in the normal way,
// Add a socket 'fd' to sockmap at location 'i'
bpf_map_update_elem(map_fd_msg, &i, fd, BPF_ANY);
After the above any socket attached to "my_sock_map", in this case
'fd', will run the BPF msg verdict program (msg_prog) on every
sendmsg and sendpage system call.
For a complete example see BPF selftests or sockmap samples.
Implementation notes:
It seemed the simplest, to me at least, to use a refcnt to ensure
psock is not lost across the sendmsg copy into the sg, the bpf program
running on the data in sg_data, and the final pass to the TCP stack.
Some performance testing may show a better method to do this and avoid
the refcnt cost, but for now use the simpler method.
Another item that will come after basic support is in place is
supporting MSG_MORE flag. At the moment we call sendpages even if
the MSG_MORE flag is set. An enhancement would be to collect the
pages into a larger scatterlist and pass down the stack. Notice that
bpf_tcp_sendmsg() could support this with some additional state saved
across sendmsg calls. I built the code to support this without having
to do refactoring work. Other features TBD include ZEROCOPY and the
TCP_RECV_QUEUE/TCP_NO_QUEUE support. This will follow initial series
shortly.
Future work could improve size limits on the scatterlist rings used
here. Currently, we use MAX_SKB_FRAGS simply because this was being
used already in the TLS case. Future work could extend the kernel sk
APIs to tune this depending on workload. This is a trade-off
between memory usage and throughput performance.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
When calling do_tcp_sendpages() from in kernel and we know the data
has no references from user side we can omit SKBTX_SHARED_FRAG flag.
This patch adds an internal flag, NO_SKBTX_SHARED_FRAG that can be used
to omit setting SKBTX_SHARED_FRAG.
The flag is not exposed to userspace because the sendpage call from
the splice logic masks out all bits except MSG_MORE.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
rtnl_lock() is widely used mutex in kernel. Some of kernel code
does memory allocations under it. In case of memory deficit this
may invoke OOM killer, but the problem is a killed task can't
exit if it's waiting for the mutex. This may be a reason of deadlock
and panic.
This patch adds a new primitive, which responds on SIGKILL, and
it allows to use it in the places, where we don't want to sleep
forever.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The new variable is only available when CONFIG_SYSCTL is enabled,
otherwise we get a link error:
net/ipv4/ip_tunnel.o: In function `ip_tunnel_init_net':
ip_tunnel.c:(.text+0x278b): undefined reference to `sysctl_fb_tunnels_only_for_init_net'
net/ipv6/sit.o: In function `sit_init_net':
sit.c:(.init.text+0x4c): undefined reference to `sysctl_fb_tunnels_only_for_init_net'
net/ipv6/ip6_tunnel.o: In function `ip6_tnl_init_net':
ip6_tunnel.c:(.init.text+0x39): undefined reference to `sysctl_fb_tunnels_only_for_init_net'
This adds an extra condition, keeping the traditional behavior when
CONFIG_SYSCTL is disabled.
Fixes: 79134e6ce2 ("net: do not create fallback tunnels for non-default namespaces")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some network devices - notably ipvlan slave - are not compatible with
any kind of rx_handler. Currently the hook can be installed but any
configuration (bridge, bond, macsec, ...) is nonfunctional.
This change allocates a priv_flag bit to mark such devices and explicitly
forbid installing a rx_handler if such bit is set. The new bit is used
by ipvlan slave device.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fallback tunnels (like tunl0, gre0, gretap0, erspan0, sit0,
ip6tnl0, ip6gre0) are automatically created when the corresponding
module is loaded.
These tunnels are also automatically created when a new network
namespace is created, at a great cost.
In many cases, netns are used for isolation purposes, and these
extra network devices are a waste of resources. We are using
thousands of netns per host, and hit the netns creation/delete
bottleneck a lot. (Many thanks to Kirill for recent work on this)
Add a new sysctl so that we can opt-out from this automatic creation.
Note that these tunnels are still created for the initial namespace,
to be the least intrusive for typical setups.
Tested:
lpk43:~# cat add_del_unshare.sh
for i in `seq 1 40`
do
(for j in `seq 1 100` ; do unshare -n /bin/true >/dev/null ; done) &
done
wait
lpk43:~# echo 0 >/proc/sys/net/core/fb_tunnels_only_for_init_net
lpk43:~# time ./add_del_unshare.sh
real 0m37.521s
user 0m0.886s
sys 7m7.084s
lpk43:~# echo 1 >/proc/sys/net/core/fb_tunnels_only_for_init_net
lpk43:~# time ./add_del_unshare.sh
real 0m4.761s
user 0m0.851s
sys 1m8.343s
lpk43:~#
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We use a two-step process to configure a filter with RSS spreading. First,
the RSS context is allocated and configured using ETHTOOL_SRSSH; this
returns an identifier (rss_context) which can then be passed to subsequent
invocations of ETHTOOL_SRXCLSRLINS to specify that the offset from the RSS
indirection table lookup should be added to the queue number (ring_cookie)
when delivering the packet. Drivers for devices which can only use the
indirection table entry directly (not add it to a base queue number)
should reject rule insertions combining RSS with a nonzero ring_cookie.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This series follows our previous one to lay out the foundations for IPSec
in user-space and extend current kernel netdev IPSec support. As noted in
our previous pull request cover letter "mlx5-updates-2018-02-28-1 (IPSec-1)",
the IPSec mechanism will be supported through our flow steering mechanism.
Therefore, we need to change the initialization order. Furthermore, IPsec
is also supported in both egress and ingress. Since our current flow
steering is egress only, we add an empty (only implemented through FPGA
steering ops) egress namespace to handle that case. We also implement
the required flow steering callbacks and logic in our FPGA driver.
We extend the FPGA support for ESN and modifying a xfrm too. Therefore, we
add support for some new FPGA command interface that supports them. The
other required bits are added too. The new features and requirements are
advertised via cap bits.
Last but not least, we revise our driver's accel_esp API. This API will be
shared between our netdev and IB driver, so we need to have all the required
functionality from both worlds.
Regards,
Aviad and Matan
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Merge tag 'mlx5-updates-2018-02-28-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux
Saeed Mahameed says:
====================
mlx5-updates-2018-02-28-2 (IPSec-2)
This series follows our previous one to lay out the foundations for IPSec
in user-space and extend current kernel netdev IPSec support. As noted in
our previous pull request cover letter "mlx5-updates-2018-02-28-1 (IPSec-1)",
the IPSec mechanism will be supported through our flow steering mechanism.
Therefore, we need to change the initialization order. Furthermore, IPsec
is also supported in both egress and ingress. Since our current flow
steering is egress only, we add an empty (only implemented through FPGA
steering ops) egress namespace to handle that case. We also implement
the required flow steering callbacks and logic in our FPGA driver.
We extend the FPGA support for ESN and modifying a xfrm too. Therefore, we
add support for some new FPGA command interface that supports them. The
other required bits are added too. The new features and requirements are
advertised via cap bits.
Last but not least, we revise our driver's accel_esp API. This API will be
shared between our netdev and IB driver, so we need to have all the required
functionality from both worlds.
Regards,
Aviad and Matan
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently ESN is not supported with IPSec device offload.
This patch adds ESN support to IPsec device offload.
Implementing new xfrm device operation to synchronize offloading device
ESN with xfrm received SN. New QP command to update SA state at the
following:
ESN 1 ESN 2 ESN 3
|-----------*-----------|-----------*-----------|-----------*
^ ^ ^ ^ ^ ^
^ - marks where QP command invoked to update the SA ESN state
machine.
| - marks the start of the ESN scope (0-2^32-1). At this point move SA
ESN overlap bit to zero and increment ESN.
* - marks the middle of the ESN scope (2^31). At this point move SA
ESN overlap bit to one.
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Yossef Efraim <yossefe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
In order to add a context to the FPGA, we need to get both the software
transform context (which includes the keys, etc) and the
source/destination IPs (which are included in the steering
rule). Therefore, we register new set of firmware like commands for
the FPGA. Each time a rule is added, the steering core infrastructure
calls the FPGA command layer. If the rule is intended for the FPGA,
it combines the IPs information with the software transformation
context and creates the respective hardware transform.
Afterwards, it calls the standard steering command layer.
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
The current code has one layer that executed FPGA commands and
the Ethernet part directly used this code. Since downstream patches
introduces support for IPSec in mlx5_ib, we need to provide some
abstractions. This patch refactors the accel code into one layer
that creates a software IPSec transformation and another one which
creates the actual hardware context.
The internal command implementation is now hidden in the FPGA
core layer. The code also adds the ability to share FPGA hardware
contexts. If two contexts are the same, only a reference count
is taken.
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
This patch adds V2 command support.
New fpga devices support extended features (udp encap, esn etc...), this
features require new hardware sadb format therefore we have a new version
of commands to manipulate it.
Signed-off-by: Yossef Efraim <yossefe@mellanox.com>
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Current hardware decrypts and authenticates incoming ESP packets.
Subsequently, the software extracts the nexthdr field, truncates the
trailer and adjusts csum accordingly.
With this patch and a capable device, the trailer is being removed
by the hardware and the nexthdr field is conveyed via PET. This way
we avoid both the need to access the trailer (cache miss) and to
compute its relative checksum, which significantly improve
the performance.
Experiment shows that trailer removal improves the performance by
2Gbps, (netperf). Both forwarding and host-to-host configurations.
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
The current code assume only SA QP commands.
Refactor in order to pave the way for new QP commands:
1. Generic cmd response format.
2. SA cmd checks are in dedicated functions.
3. Aligned debug prints.
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
This series consists of some fixes and refactors for the mlx5 drivers,
especially around the FPGA and flow steering. Most of them are trivial
fixes and are the foundation of allowing IPSec acceleration from user-space.
We use flow steering abstraction in order to accelerate IPSec packets.
When a user creates a steering rule, [s]he states that we'll carry an
encrypt/decrypt flow action (using a specific configuration) for every
packet which conforms to a certain match. Since currently offloading these
packets is done via FPGA, we'll add another set of flow steering ops.
These ops will execute the required FPGA commands and then call the
standard steering ops.
In order to achieve this, we need that the commands will get all the
required information. Therefore, we pass the fte object and embed the
flow_action struct inside the fte. In addition, we add the shim layer
that will later be used for alternating between the standard and the
FPGA steering commands.
Some fixes, like " net/mlx5e: Wait for FPGA command responses with a timeout"
are very relevant for user-space applications, as these applications could
be killed, but we still want to wait for the FPGA and update the kernel's
database.
Regards,
Aviad and Matan
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Merge tag 'mlx5-updates-2018-02-28-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux
Saeed Mahameed says:
====================
mlx5-updates-2018-02-28-1 (IPSec-1)
This series consists of some fixes and refactors for the mlx5 drivers,
especially around the FPGA and flow steering. Most of them are trivial
fixes and are the foundation of allowing IPSec acceleration from user-space.
We use flow steering abstraction in order to accelerate IPSec packets.
When a user creates a steering rule, [s]he states that we'll carry an
encrypt/decrypt flow action (using a specific configuration) for every
packet which conforms to a certain match. Since currently offloading these
packets is done via FPGA, we'll add another set of flow steering ops.
These ops will execute the required FPGA commands and then call the
standard steering ops.
In order to achieve this, we need that the commands will get all the
required information. Therefore, we pass the fte object and embed the
flow_action struct inside the fte. In addition, we add the shim layer
that will later be used for alternating between the standard and the
FPGA steering commands.
Some fixes, like " net/mlx5e: Wait for FPGA command responses with a timeout"
are very relevant for user-space applications, as these applications could
be killed, but we still want to wait for the FPGA and update the kernel's
database.
Regards,
Aviad and Matan
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
the ipvlan device driver defines and uses 2 bits inside the priv_flags
net_device field. Such bits and the related helper are used only
inside the ipvlan device driver, and the core networking does not
need to be aware of them.
This change moves netif_is_ipvlan* helper in the ipvlan driver and
re-implement them looking for ipvlan specific symbols instead of
using priv_flags.
Overall this frees two bits inside priv_flags - and move the following
ones to avoid gaps - without any intended functional change.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add helper functions that check if a protocol is
part of a flow steering match criteria.
Signed-off-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Currently, we don't support egress flow steering namespace in mlx5
flow steering core implementation. However, when we want to encrypt
a packet, we model it as a flow steering rule in the egress path.
To overcome this, we add an empty egress namespace to flow steering.
This namespace is initialized only when ipsec support exists.
In the future, this will grow to a full blown full steering
implementation, resembling the ingress path.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
The has_tag member will indicate whether a tag action was specified
in flow specification.
A flow tag 0 = MLX5_FS_DEFAULT_FLOW_TAG is assumed a valid flow tag
that is currently used by mlx5 RDMA driver, whereas in HW flow_tag = 0
means that the user doesn't care about flow_tag. HW always provide
a flow_tag = 0 if all flow tags requested on a specific flow are 0.
So we need a way (in the driver) to differentiate between a user really
requesting flow_tag = 0 and a user who does not care, in order to be
able to report conflicting flow tags on a specific flow.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Aviad Yehezkel <aviadye@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
All of the conflicts were cases of overlapping changes.
In net/core/devlink.c, we have to make care that the
resouce size_params have become a struct member rather
than a pointer to such an object.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Use an appropriate TSQ pacing shift in mac80211, from Toke
Høiland-Jørgensen.
2) Just like ipv4's ip_route_me_harder(), we have to use skb_to_full_sk
in ip6_route_me_harder, from Eric Dumazet.
3) Fix several shutdown races and similar other problems in l2tp, from
James Chapman.
4) Handle missing XDP flush properly in tuntap, for real this time.
From Jason Wang.
5) Out-of-bounds access in powerpc ebpf tailcalls, from Daniel
Borkmann.
6) Fix phy_resume() locking, from Andrew Lunn.
7) IFLA_MTU values are ignored on newlink for some tunnel types, fix
from Xin Long.
8) Revert F-RTO middle box workarounds, they only handle one dimension
of the problem. From Yuchung Cheng.
9) Fix socket refcounting in RDS, from Ka-Cheong Poon.
10) Don't allow ppp unit registration to an unregistered channel, from
Guillaume Nault.
11) Various hv_netvsc fixes from Stephen Hemminger.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (98 commits)
hv_netvsc: propagate rx filters to VF
hv_netvsc: filter multicast/broadcast
hv_netvsc: defer queue selection to VF
hv_netvsc: use napi_schedule_irqoff
hv_netvsc: fix race in napi poll when rescheduling
hv_netvsc: cancel subchannel setup before halting device
hv_netvsc: fix error unwind handling if vmbus_open fails
hv_netvsc: only wake transmit queue if link is up
hv_netvsc: avoid retry on send during shutdown
virtio-net: re enable XDP_REDIRECT for mergeable buffer
ppp: prevent unregistered channels from connecting to PPP units
tc-testing: skbmod: fix match value of ethertype
mlxsw: spectrum_switchdev: Check success of FDB add operation
net: make skb_gso_*_seglen functions private
net: xfrm: use skb_gso_validate_network_len() to check gso sizes
net: sched: tbf: handle GSO_BY_FRAGS case in enqueue
net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len
rds: Incorrect reference counting in TCP socket creation
net: ethtool: don't ignore return from driver get_fecparam method
vrf: check forwarding on the original netdevice when generating ICMP dest unreachable
...
They're very hard to use properly as they do not consider the
GSO_BY_FRAGS case. Code should use skb_gso_validate_network_len
and skb_gso_validate_mac_len as they do consider this case.
Make the seglen functions static, which stops people using them
outside of skbuff.c
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If you take a GSO skb, and split it into packets, will the network
length (L3 headers + L4 headers + payload) of those packets be small
enough to fit within a given MTU?
skb_gso_validate_mtu gives you the answer to that question. However,
we recently added to add a way to validate the MAC length of a split GSO
skb (L2+L3+L4+payload), and the names get confusing, so rename
skb_gso_validate_mtu to skb_gso_validate_network_len
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull libnvdimm fixes from Dan Williams:
"A 4.16 regression fix, three fixes for -stable, and a cleanup fix:
- During the merge window support for the new ACPI NVDIMM Platform
Capabilities structure disabled support for "deep flush", a
force-unit- access like mechanism for persistent memory. Restore
that mechanism.
- VFIO like RDMA is yet one more memory registration / pinning
interface that is incompatible with Filesystem-DAX. Disable long
term pins of Filesystem-DAX mappings via VFIO.
- The Filesystem-DAX detection to prevent long terms pins mistakenly
also disabled Device-DAX pins which are not subject to the same
block- map collision concerns.
- Similar to the setup path, softlockup warnings can trigger in the
shutdown path for large persistent memory namespaces. Teach
for_each_device_pfn() to perform cond_resched() in all cases.
- Boaz noticed that the might_sleep() in dax_direct_access() is stale
as of the v4.15 kernel.
These have received a build success notification from the 0day robot,
and the longterm pin fixes have appeared in -next. However, I recently
rebased the tree to remove some other fixes that need to be reworked
after review feedback.
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
memremap: fix softlockup reports at teardown
libnvdimm: re-enable deep flush for pmem devices via fsync()
vfio: disable filesystem-dax page pinning
dax: fix vma_is_fsdax() helper
dax: ->direct_access does not sleep anymore
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Merge tag 'for-linus-20180302' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A collection of fixes for this series. This is a little larger than
usual at this time, but that's mainly because I was out on vacation
last week. Nothing in here is major in any way, it's just two weeks of
fixes. This contains:
- NVMe pull from Keith, with a set of fixes from the usual suspects.
- mq-deadline zone unlock fix from Damien, fixing an issue with the
SMR zone locking added for 4.16.
- two bcache fixes sent in by Michael, with changes from Coly and
Tang.
- comment typo fix from Eric for blktrace.
- return-value error handling fix for nbd, from Gustavo.
- fix a direct-io case where we don't defer to a completion handler,
making us sleep from IRQ device completion. From Jan.
- a small series from Jan fixing up holes around handling of bdev
references.
- small set of regression fixes from Jiufei, mostly fixing problems
around the gendisk pointer -> partition index change.
- regression fix from Ming, fixing a boundary issue with the discard
page cache invalidation.
- two-patch series from Ming, fixing both a core blk-mq-sched and
kyber issue around token freeing on a requeue condition"
* tag 'for-linus-20180302' of git://git.kernel.dk/linux-block: (24 commits)
block: fix a typo
block: display the correct diskname for bio
block: fix the count of PGPGOUT for WRITE_SAME
mq-deadline: Make sure to always unlock zones
nvmet: fix PSDT field check in command format
nvme-multipath: fix sysfs dangerously created links
nbd: fix return value in error handling path
bcache: fix kcrashes with fio in RAID5 backend dev
bcache: correct flash only vols (check all uuids)
blktrace_api.h: fix comment for struct blk_user_trace_setup
blockdev: Avoid two active bdev inodes for one device
genhd: Fix BUG in blkdev_open()
genhd: Fix use after free in __blkdev_get()
genhd: Add helper put_disk_and_module()
genhd: Rename get_disk() to get_disk_and_module()
genhd: Fix leaked module reference for NVME devices
direct-io: Fix sleep in atomic due to sync AIO
nvme-pci: Fix nvme queue cleanup if IRQ setup fails
block: kyber: fix domain token leak during requeue
blk-mq: don't call io sched's .requeue_request when requeueing rq to ->dispatch
...
In order to remove a fair amount of duplication in the different 10G PHY
drivers, export all gen10g_* functions to be able to make use of those.
While we are at it, rename gen10g_soft_reset() to gen10g_no_soft_reset()
to illustrate what it does.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
The various MFC entries are being held in the same kind of mr_tables
for both ipmr and ip6mr, and their traversal logic is identical.
Also, with the exception of the addresses [and other small tidbits]
the major bulk of the nla setting is identical.
Unite as much of the dumping as possible between the two.
Notice this requires creating an mr_table iterator for each, as the
for-each preprocessor macro can't be used by the common logic.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
MFC_NOTIFY exists in ip6mr, probably as some legacy code
[was already removed for ipmr in commit
06bd6c0370 ("net: ipmr: remove unused MFC_NOTIFY flag and make the flags enum").
Remove it from ip6mr as well, and move the enum into a common file;
Notice MFC_OFFLOAD is currently only used by ipmr.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Same as previously done with the mfc seq, the logic for the vif seq is
refactored to be shared between ipmr and ip6mr.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the exception of the final dump, ipmr and ip6mr have the exact same
seq logic for traversing a given mr_table. Refactor that code and make
it common.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipmr and ip6mr utilize the exact same methods for searching the
hashed resolved connections, difference being only in the construction
of the hash comparison key.
In order to unite the flow, introduce an mr_table operation set that
would contain the protocol specific information required for common
flows, in this case - the hash parameters and a comparison key
representing a (*,*) route.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mfc_cache and mfc6_cache are almost identical - the main difference is
in the origin/group addresses and comparison-key. Make a common
structure encapsulating most of the multicast routing logic - mr_mfc
and convert both ipmr and ip6mr into using it.
For easy conversion [casting, in this case] mr_mfc has to be the first
field inside every multicast routing abstraction utilizing it.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that both ipmr and ip6mr are using the same mr_table structure,
we can have a common function to allocate & initialize a new instance.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Following previous changes to ip6mr, mr_table and mr6_table are
basically the same [up to mr6_table having additional '6' suffixes to
its variable names].
Move the common structure definition into a common header; This
requires renaming all references in ip6mr to variables that had the
distinct suffix.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 8fb472c09b ("ipmr: improve hash scalability") ipmr has
been using rhashtable as a basis for its mfc routes, but ip6mr is
currently still using the old private MFC hash implementation.
Align ip6mr to the current ipmr implementation.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In ipmr the mr_table socket is handled under RCU. Introduce the same
for ip6mr.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The two implementations have almost identical structures - vif_device and
mif_device. As a step toward uniforming the mr_tables, eliminate the
mif_device and relocate the vif_device definition into a new common
header file.
Also, introduce a common initializing function for setting most of the
vif_device fields in a new common source file. This requires modifying
the ipv{4,6] Kconfig and ipv4 makefile as we're introducing a new common
config option - CONFIG_IP_MROUTE_COMMON.
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bio_devname use __bdevname to display the device name, and can
only show the major and minor of the part0,
Fix this by using disk_name to display the correct name.
Fixes: 74d46992e0 ("block: replace bi_bdev with a gendisk pointer and partitions index")
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Negotiate the interface format with the MAC rather than requiring it to
be a fixed type specified solely by the SFP module. This allows modules
that can work with several different interface signalling formats to
select a format compatible with the MAC - for example, a Fiber module
supporing Gigabit ethernet and faster connected to a Gigabit only MAC
needs to select the 1000BASE-X mode.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Mark Bloch <markb@mellanox.com>
=========
Add IB representor when in switchdev mode
The following series adds support for an IB (RAW Ethernet only) device
representor which is created when the user switches to switchdev mode.
Today when switching to switchdev mode the only representors which are
created are net devices. Each netdev is a representor of a virtual
function and any data sent via the representor is received on the virtual
function, and any data sent via the virtual function is received by the
representor.
For the mlx5 driver the main use of this functionality is to be able to
use Open vSwitch on the hypervisor in order to manage/control traffic
from/to the virtual functions. Open vSwitch can also work with DPDK
devices and not just net devices, this series exposes an IB device, which
Mellanox PMD driver uses, which then can be used by Open vSwitch DPDK.
An IB device representor exposes only RAW Ethernet QP capabilities and
the ability to create flow rules to direct traffic to its RX queues. The
state of the IB device (ACTIVE/DOWN etc..) is based on the state of the
corresponding net device representor. No other RDMA/RoCE functionality is
currently supported and no GID table is exposed.
=========
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Merge tag 'mlx5-updates-2018-02-23' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux
Saeed Mahameed says:
mlx5-update-2018-02-23 (IB representors)
From: Mark Bloch <markb@mellanox.com>
=========
Add IB representor when in switchdev mode
The following series adds support for an IB (RAW Ethernet only) device
representor which is created when the user switches to switchdev mode.
Today when switching to switchdev mode the only representors which are
created are net devices. Each netdev is a representor of a virtual
function and any data sent via the representor is received on the virtual
function, and any data sent via the virtual function is received by the
representor.
For the mlx5 driver the main use of this functionality is to be able to
use Open vSwitch on the hypervisor in order to manage/control traffic
from/to the virtual functions. Open vSwitch can also work with DPDK
devices and not just net devices, this series exposes an IB device, which
Mellanox PMD driver uses, which then can be used by Open vSwitch DPDK.
An IB device representor exposes only RAW Ethernet QP capabilities and
the ability to create flow rules to direct traffic to its RX queues. The
state of the IB device (ACTIVE/DOWN etc..) is based on the state of the
corresponding net device representor. No other RDMA/RoCE functionality is
currently supported and no GID table is exposed.
=========
Signed-off-by: David S. Miller <davem@davemloft.net>
commit f5e64032a7 ("net: phy: fix resume handling") changes the
locking semantics for phy_resume() such that the caller now needs to
hold the phy mutex. Not all call sites were adopted to this new
semantic, resulting in warnings from the added
WARN_ON(!mutex_is_locked(&phydev->lock)). Rather than change the
semantics, add a __phy_resume() and restore the old behavior of
phy_resume().
Reported-by: Heiner Kallweit <hkallweit1@gmail.com>
Fixes: f5e64032a7 ("net: phy: fix resume handling")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Gerd reports that ->i_mode may contain other bits besides S_IFCHR. Use
S_ISCHR() instead. Otherwise, get_user_pages_longterm() may fail on
device-dax instances when those are meant to be explicitly allowed.
Fixes: 2bb6d28370 ("mm: introduce get_user_pages_longterm")
Cc: <stable@vger.kernel.org>
Reported-by: Gerd Rausch <gerd.rausch@oracle.com>
Acked-by: Jane Chu <jane.chu@oracle.com>
Reported-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull x86 fixes from Thomas Gleixner:
"Yet another pile of melted spectrum related changes:
- sanitize the array_index_nospec protection mechanism: Remove the
overengineered array_index_nospec_mask_check() magic and allow
const-qualified types as index to avoid temporary storage in a
non-const local variable.
- make the microcode loader more robust by properly propagating error
codes. Provide information about new feature bits after micro code
was updated so administrators can act upon.
- optimizations of the entry ASM code which reduce code footprint and
make the code simpler and faster.
- fix the {pmd,pud}_{set,clear}_flags() implementations to work
properly on paravirt kernels by removing the address translation
operations.
- revert the harmful vmexit_fill_RSB() optimization
- use IBRS around firmware calls
- teach objtool about retpolines and add annotations for indirect
jumps and calls.
- explicitly disable jumplabel patching in __init code and handle
patching failures properly instead of silently ignoring them.
- remove indirect paravirt calls for writing the speculation control
MSR as these calls are obviously proving the same attack vector
which is tried to be mitigated.
- a few small fixes which address build issues with recent compiler
and assembler versions"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR path as unlikely()
KVM/x86: Remove indirect MSR op calls from SPEC_CTRL
objtool, retpolines: Integrate objtool with retpoline support more closely
x86/entry/64: Simplify ENCODE_FRAME_POINTER
extable: Make init_kernel_text() global
jump_label: Warn on failed jump_label patching attempt
jump_label: Explicitly disable jump labels in __init code
x86/entry/64: Open-code switch_to_thread_stack()
x86/entry/64: Move ASM_CLAC to interrupt_entry()
x86/entry/64: Remove 'interrupt' macro
x86/entry/64: Move the switch_to_thread_stack() call to interrupt_entry()
x86/entry/64: Move ENTER_IRQ_STACK from interrupt macro to interrupt_entry
x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function
x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP
objtool: Add module specific retpoline rules
objtool: Add retpoline validation
objtool: Use existing global variables for options
x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute()
x86/boot, objtool: Annotate indirect jump in secondary_startup_64()
x86/paravirt, objtool: Annotate indirect calls
...
- optimization for the exitless interrupt support that was merged in 4.16-rc1
- improve the branch prediction blocking for nested KVM
- replace some jump tables with switch statements to improve expoline performance
- fixes for multiple epoch facility
ARM:
- fix the interaction of userspace irqchip VMs with in-kernel irqchip VMs
- make sure we can build 32-bit KVM/ARM with gcc-8.
x86:
- fixes for AMD SEV
- fixes for Intel nested VMX, emulated UMIP and a dump_stack() on VM startup
- fixes for async page fault migration
- small optimization to PV TLB flush (new in 4.16-rc1)
- syzkaller fixes
Generic:
- compiler warning fixes
- syzkaller fixes
- more improvements to the kvm_stat tool
Two more small Spectre fixes are going to reach you via Ingo.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Paolo Bonzini:
"s390:
- optimization for the exitless interrupt support that was merged in 4.16-rc1
- improve the branch prediction blocking for nested KVM
- replace some jump tables with switch statements to improve expoline performance
- fixes for multiple epoch facility
ARM:
- fix the interaction of userspace irqchip VMs with in-kernel irqchip VMs
- make sure we can build 32-bit KVM/ARM with gcc-8.
x86:
- fixes for AMD SEV
- fixes for Intel nested VMX, emulated UMIP and a dump_stack() on VM startup
- fixes for async page fault migration
- small optimization to PV TLB flush (new in 4.16-rc1)
- syzkaller fixes
Generic:
- compiler warning fixes
- syzkaller fixes
- more improvements to the kvm_stat tool
Two more small Spectre fixes are going to reach you via Ingo"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (40 commits)
KVM: SVM: Fix SEV LAUNCH_SECRET command
KVM: SVM: install RSM intercept
KVM: SVM: no need to call access_ok() in LAUNCH_MEASURE command
include: psp-sev: Capitalize invalid length enum
crypto: ccp: Fix sparse, use plain integer as NULL pointer
KVM: X86: Avoid traversing all the cpus for pv tlb flush when steal time is disabled
x86/kvm: Make parse_no_xxx __init for kvm
KVM: x86: fix backward migration with async_PF
kvm: fix warning for non-x86 builds
kvm: fix warning for CONFIG_HAVE_KVM_EVENTFD builds
tools/kvm_stat: print 'Total' line for multiple events only
tools/kvm_stat: group child events indented after parent
tools/kvm_stat: separate drilldown and fields filtering
tools/kvm_stat: eliminate extra guest/pid selection dialog
tools/kvm_stat: mark private methods as such
tools/kvm_stat: fix debugfs handling
tools/kvm_stat: print error on invalid regex
tools/kvm_stat: fix crash when filtering out all non-child trace events
tools/kvm_stat: avoid 'is' for equality checks
tools/kvm_stat: use a more pythonic way to iterate over dictionaries
...
When two blkdev_open() calls for a partition race with device removal
and recreation, we can hit BUG_ON(!bd_may_claim(bdev, whole, holder)) in
blkdev_open(). The race can happen as follows:
CPU0 CPU1 CPU2
del_gendisk()
bdev_unhash_inode(part1);
blkdev_open(part1, O_EXCL) blkdev_open(part1, O_EXCL)
bdev = bd_acquire() bdev = bd_acquire()
blkdev_get(bdev)
bd_start_claiming(bdev)
- finds old inode 'whole'
bd_prepare_to_claim() -> 0
bdev_unhash_inode(whole);
<device removed>
<new device under same
number created>
blkdev_get(bdev);
bd_start_claiming(bdev)
- finds new inode 'whole'
bd_prepare_to_claim()
- this also succeeds as we have
different 'whole' here...
- bad things happen now as we
have two exclusive openers of
the same bdev
The problem here is that block device opens can see various intermediate
states while gendisk is shutting down and then being recreated.
We fix the problem by introducing new lookup_sem in gendisk that
synchronizes gendisk deletion with get_gendisk() and furthermore by
making sure that get_gendisk() does not return gendisk that is being (or
has been) deleted. This makes sure that once we ever manage to look up
newly created bdev inode, we are also guaranteed that following
get_gendisk() will either return failure (and we fail open) or it
returns gendisk for the new device and following bdget_disk() will
return new bdev inode (i.e., blkdev_open() follows the path as if it is
completely run after new device is created).
Reported-and-analyzed-by: Hou Tao <houtao1@huawei.com>
Tested-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a proper counterpart to get_disk_and_module() -
put_disk_and_module(). Currently it is opencoded in several places.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rename get_disk() to get_disk_and_module() to make sure what the
function does. It's not a great name but at least it is now clear that
put_disk() is not it's counterpart.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
