Sometimes, we may call tcp receive zerocopy when inq is 0,
or inq < PAGE_SIZE, in which case we cannot remap pages. In this case,
simply return the appropriate hint for regular copying without taking
mmap_sem.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Refactor frag-is-remappable test for tcp receive zerocopy. This is
part of a patch set that introduces short-circuited hybrid copies
for small receive operations, which results in roughly 33% fewer
syscalls for small RPC scenarios.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Refactor skb frag fast-forwarding for tcp receive zerocopy. This is
part of a patch set that introduces short-circuited hybrid copies
for small receive operations, which results in roughly 33% fewer
syscalls for small RPC scenarios.
skb_advance_to_frag(), given a skb and an offset into the skb,
iterates from the first frag for the skb until we're at the frag
specified by the offset. Assuming the offset provided refers to how
many bytes in the skb are already read, the returned frag points to
the next frag we may read from, while offset_frag is set to the number
of bytes from this frag that we have already read.
If frag is not null and offset_frag is equal to 0, then we may be able
to map this frag's page into the process address space with
vm_insert_page(). However, if offset_frag is not equal to 0, then we
cannot do so.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Refactor tcp_recvmsg() by splitting it into locked and unlocked
portions. Callers already holding the socket lock and not using
ERRQUEUE/cmsg/busy polling can simply call tcp_recvmsg_locked().
This is in preparation for a short-circuit copy performed by
TCP receive zerocopy for small (< PAGE_SIZE, or otherwise requested
by the user) reads.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When TCP receive zerocopy does not successfully map the entire
requested space, it outputs a 'hint' that the caller should recvmsg().
Augment zerocopy to accept a user buffer that it tries to copy this
hint into - if it is possible to copy the entire hint, it will do so.
This elides a recvmsg() call for received traffic that isn't exactly
page-aligned in size.
This was tested with RPC-style traffic of arbitrary sizes. Normally,
each received message required at least one getsockopt() call, and one
recvmsg() call for the remaining unaligned data.
With this change, almost all of the recvmsg() calls are eliminated,
leading to a savings of about 25%-50% in number of system calls
for RPC-style workloads.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Andrea Mayer says:
====================
seg6: add support for SRv6 End.DT4/DT6 behavior
This patchset provides support for the SRv6 End.DT4 and End.DT6 (VRF mode)
behaviors.
The SRv6 End.DT4 behavior is used to implement multi-tenant IPv4 L3 VPNs. It
decapsulates the received packets and performs IPv4 routing lookup in the
routing table of the tenant. The SRv6 End.DT4 Linux implementation leverages a
VRF device in order to force the routing lookup into the associated routing
table.
The SRv6 End.DT4 behavior is defined in the SRv6 Network Programming [1].
The Linux kernel already offers an implementation of the SRv6 End.DT6 behavior
which allows us to set up IPv6 L3 VPNs over SRv6 networks. This new
implementation of DT6 is based on the same VRF infrastructure already exploited
for implementing the SRv6 End.DT4 behavior. The aim of the new SRv6 End.DT6 in
VRF mode consists in simplifying the construction of IPv6 L3 VPN services in
the multi-tenant environment.
Currently, the two SRv6 End.DT6 implementations (legacy and VRF mode)
coexist seamlessly and can be chosen according to the context and the user
preferences.
- Patch 1 is needed to solve a pre-existing issue with tunneled packets
when a sniffer is attached;
- Patch 2 improves the management of the seg6local attributes used by the
SRv6 behaviors;
- Patch 3 adds support for optional attributes in SRv6 behaviors;
- Patch 4 introduces two callbacks used for customizing the
creation/destruction of a SRv6 behavior;
- Patch 5 is the core patch that adds support for the SRv6 End.DT4
behavior;
- Patch 6 introduces the VRF support for SRv6 End.DT6 behavior;
- Patch 7 adds the selftest for SRv6 End.DT4 behavior;
- Patch 8 adds the selftest for SRv6 End.DT6 (VRF mode) behavior.
Regarding iproute2, the support for the new "vrftable" attribute, required by
both SRv6 End.DT4 and End.DT6 (VRF mode) behaviors, is provided in a different
patchset that will follow shortly.
I would like to thank David Ahern for his support during the development of
this patchset.
[1] https://tools.ietf.org/html/draft-ietf-spring-srv6-network-programming
====================
Link: https://lore.kernel.org/r/20201202130517.4967-1-andrea.mayer@uniroma2.it
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
this selftest is designed for evaluating the new SRv6 End.DT6 (VRF) behavior
used, in this example, for implementing IPv6 L3 VPN use cases.
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Paolo Lungaroni <paolo.lungaroni@cnit.it>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
this selftest is designed for evaluating the new SRv6 End.DT4 behavior
used, in this example, for implementing IPv4 L3 VPN use cases.
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
SRv6 End.DT6 is defined in the SRv6 Network Programming [1].
The Linux kernel already offers an implementation of the SRv6
End.DT6 behavior which permits IPv6 L3 VPNs over SRv6 networks. This
implementation is not particularly suitable in contexts where we need to
deploy IPv6 L3 VPNs among different tenants which share the same network
address schemes. The underlying problem lies in the fact that the
current version of DT6 (called legacy DT6 from now on) needs a complex
configuration to be applied on routers which requires ad-hoc routes and
routing policy rules to ensure the correct isolation of tenants.
Consequently, a new implementation of DT6 has been introduced with the
aim of simplifying the construction of IPv6 L3 VPN services in the
multi-tenant environment using SRv6 networks. To accomplish this task,
we reused the same VRF infrastructure and SRv6 core components already
exploited for implementing the SRv6 End.DT4 behavior.
Currently the two End.DT6 implementations coexist seamlessly and can be
used depending on the context and the user preferences. So, in order to
support both versions of DT6 a new attribute (vrftable) has been
introduced which allows us to differentiate the implementation of the
behavior to be used.
A SRv6 End.DT6 legacy behavior is still instantiated using a command
like the following one:
$ ip -6 route add 2001:db8::1 encap seg6local action End.DT6 table 100 dev eth0
While to instantiate the SRv6 End.DT6 in VRF mode, the command is still
pretty straight forward:
$ ip -6 route add 2001:db8::1 encap seg6local action End.DT6 vrftable 100 dev eth0.
Obviously as in the case of SRv6 End.DT4, the VRF strict_mode parameter
must be set (net.vrf.strict_mode=1) and the VRF associated with table
100 must exist.
Please note that the instances of SRv6 End.DT6 legacy and End.DT6 VRF
mode can coexist in the same system/configuration without problems.
[1] https://tools.ietf.org/html/draft-ietf-spring-srv6-network-programming
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
SRv6 End.DT4 is defined in the SRv6 Network Programming [1].
The SRv6 End.DT4 is used to implement IPv4 L3VPN use-cases in
multi-tenants environments. It decapsulates the received packets and it
performs IPv4 routing lookup in the routing table of the tenant.
The SRv6 End.DT4 Linux implementation leverages a VRF device in order to
force the routing lookup into the associated routing table.
To make the End.DT4 work properly, it must be guaranteed that the routing
table used for routing lookup operations is bound to one and only one
VRF during the tunnel creation. Such constraint has to be enforced by
enabling the VRF strict_mode sysctl parameter, i.e:
$ sysctl -wq net.vrf.strict_mode=1.
At JANOG44, LINE corporation presented their multi-tenant DC architecture
using SRv6 [2]. In the slides, they reported that the Linux kernel is
missing the support of SRv6 End.DT4 behavior.
The SRv6 End.DT4 behavior can be instantiated using a command similar to
the following:
$ ip route add 2001:db8::1 encap seg6local action End.DT4 vrftable 100 dev eth0
We introduce the "vrftable" extension in iproute2 in a following patch.
[1] https://tools.ietf.org/html/draft-ietf-spring-srv6-network-programming
[2] https://speakerdeck.com/line_developers/line-data-center-networking-with-srv6
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We introduce two callbacks used for customizing the creation/destruction of
a SRv6 behavior. Such callbacks are defined in the new struct
seg6_local_lwtunnel_ops and hereafter we provide a brief description of
them:
- build_state(...): used for calling the custom constructor of the
behavior during its initialization phase and after all the attributes
have been parsed successfully;
- destroy_state(...): used for calling the custom destructor of the
behavior before it is completely destroyed.
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Before this patch, each SRv6 behavior specifies a set of required
attributes that must be provided by the userspace application when such
behavior is going to be instantiated. If at least one of the required
attributes is not provided, the creation of the behavior fails.
The SRv6 behavior framework lacks a way to manage optional attributes.
By definition, an optional attribute for a SRv6 behavior consists of an
attribute which may or may not be provided by the userspace. Therefore,
if an optional attribute is missing (and thus not supplied by the user)
the creation of the behavior goes ahead without any issue.
This patch explicitly differentiates the required attributes from the
optional attributes. In particular, each behavior can declare a set of
required attributes and a set of optional ones.
The semantic of the required attributes remains *totally* unaffected by
this patch. The introduction of the optional attributes does NOT impact
on the backward compatibility of the existing SRv6 behaviors.
It is essential to note that if an (optional or required) attribute is
supplied to a SRv6 behavior which does not expect it, the behavior
simply discards such attribute without generating any error or warning.
This operating mode remained unchanged both before and after the
introduction of the optional attributes extension.
The optional attributes are one of the key components used to implement
the SRv6 End.DT6 behavior based on the Virtual Routing and Forwarding
(VRF) framework. The optional attributes make possible the coexistence
of the already existing SRv6 End.DT6 implementation with the new SRv6
End.DT6 VRF-based implementation without breaking any backward
compatibility. Further details on the SRv6 End.DT6 behavior (VRF mode)
are reported in subsequent patches.
From the userspace point of view, the support for optional attributes DO
NOT require any changes to the userspace applications, i.e: iproute2
unless new attributes (required or optional) are needed.
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Depending on the attribute (i.e.: SEG6_LOCAL_SRH, SEG6_LOCAL_TABLE, etc),
the parse() callback performs some validity checks on the provided input
and updates the tunnel state (slwt) with the result of the parsing
operation. However, an attribute may also need to reserve some additional
resources (i.e.: memory or setting up an eBPF program) in the parse()
callback to complete the parsing operation.
The parse() callbacks are invoked by the parse_nla_action() for each
attribute belonging to a specific behavior. Given a behavior with N
attributes, if the parsing of the i-th attribute fails, the
parse_nla_action() returns immediately with an error. Nonetheless, the
resources acquired during the parsing of the i-1 attributes are not freed
by the parse_nla_action().
Attributes which acquire resources must release them *in an explicit way*
in both the seg6_local_{build/destroy}_state(). However, adding a new
attribute of this type requires changes to
seg6_local_{build/destroy}_state() to release the resources correctly.
The seg6local infrastructure still lacks a simple and structured way to
release the resources acquired in the parse() operations.
We introduced a new callback in the struct seg6_action_param named
destroy(). This callback releases any resource which may have been acquired
in the parse() counterpart. Each attribute may or may not implement the
destroy() callback depending on whether it needs to free some acquired
resources.
The destroy() callback comes with several of advantages:
1) we can have many attributes as we want for a given behavior with no
need to explicitly free the taken resources;
2) As in case of the seg6_local_build_state(), the
seg6_local_destroy_state() does not need to handle the release of
resources directly. Indeed, it calls the destroy_attrs() function which
is in charge of calling the destroy() callback for every set attribute.
We do not need to patch seg6_local_{build/destroy}_state() anymore as
we add new attributes;
3) the code is more readable and better structured. Indeed, all the
information needed to handle a given attribute are contained in only
one place;
4) it facilitates the integration with new features introduced in further
patches.
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Before this patch, a sniffer attached to a VRF used as the receiving
interface of L3 tunneled packets detects them as malformed packets and
it complains about that (i.e.: tcpdump shows bogus packets).
The reason is that a tunneled L3 packet does not carry any L2
information and when the VRF is set as the receiving interface of a
decapsulated L3 packet, no mac header is currently set or valid.
Therefore, the purpose of this patch consists of adding a MAC header to
any packet which is directly received on the VRF interface ONLY IF:
i) a sniffer is attached on the VRF and ii) the mac header is not set.
In this case, the mac address of the VRF is copied in both the
destination and the source address of the ethernet header. The protocol
type is set either to IPv4 or IPv6, depending on which L3 packet is
received.
Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
First set of patches for v5.11. rtw88 getting improvements to work
better with Bluetooth and other driver also getting some new features.
mhi-ath11k-immutable branch was pulled from mhi tree to avoid
conflicts with mhi tree.
Major changes:
rtw88
* major bluetooth co-existance improvements
wilc1000
* Wi-Fi Multimedia (WMM) support
ath11k
* Fast Initial Link Setup (FILS) discovery and unsolicited broadcast
probe response support
* qcom,ath11k-calibration-variant Device Tree setting
* cold boot calibration support
* new DFS region: JP
wnc36xx
* enable connection monitoring and keepalive in firmware
ath10k
* firmware IRAM recovery feature
mhi
* merge mhi-ath11k-immutable branch to make MHI API change go smoothly
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Merge tag 'wireless-drivers-next-2020-12-03' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next
Kalle Valo says:
====================
wireless-drivers-next patches for v5.11
First set of patches for v5.11. rtw88 getting improvements to work
better with Bluetooth and other driver also getting some new features.
mhi-ath11k-immutable branch was pulled from mhi tree to avoid
conflicts with mhi tree.
Major changes:
rtw88
* major bluetooth co-existance improvements
wilc1000
* Wi-Fi Multimedia (WMM) support
ath11k
* Fast Initial Link Setup (FILS) discovery and unsolicited broadcast
probe response support
* qcom,ath11k-calibration-variant Device Tree setting
* cold boot calibration support
* new DFS region: JP
wnc36xx
* enable connection monitoring and keepalive in firmware
ath10k
* firmware IRAM recovery feature
mhi
* merge mhi-ath11k-immutable branch to make MHI API change go smoothly
* tag 'wireless-drivers-next-2020-12-03' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next: (180 commits)
wl1251: remove trailing semicolon in macro definition
airo: remove trailing semicolon in macro definition
wilc1000: added queue support for WMM
wilc1000: call complete() for failure in wilc_wlan_txq_add_cfg_pkt()
wilc1000: free resource in wilc_wlan_txq_add_mgmt_pkt() for failure path
wilc1000: free resource in wilc_wlan_txq_add_net_pkt() for failure path
wilc1000: added 'ndo_set_mac_address' callback support
brcmfmac: expose firmware config files through modinfo
wlcore: Switch to using the new API kobj_to_dev()
rtw88: coex: add feature to enhance HID coexistence performance
rtw88: coex: upgrade coexistence A2DP mechanism
rtw88: coex: add action for coexistence in hardware initial
rtw88: coex: add function to avoid cck lock
rtw88: coex: change the coexistence mechanism for WLAN connected
rtw88: coex: change the coexistence mechanism for HID
rtw88: coex: update AFH information while in free-run mode
rtw88: coex: update the mechanism for A2DP + PAN
rtw88: coex: add debug message
rtw88: coex: run coexistence when WLAN entering/leaving LPS
Revert "rtl8xxxu: Add Buffalo WI-U3-866D to list of supported devices"
...
====================
Link: https://lore.kernel.org/r/20201203185732.9CFA5C433ED@smtp.codeaurora.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When building FSL_DPAA_ETH the following build error shows up:
/tmp/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c: In function ‘dpaa_fq_init’:
/tmp/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c:1135:9: error: too few arguments to function ‘xdp_rxq_info_reg’
1135 | err = xdp_rxq_info_reg(&dpaa_fq->xdp_rxq, dpaa_fq->net_dev,
| ^~~~~~~~~~~~~~~~
Commit b02e5a0ebb ("xsk: Propagate napi_id to XDP socket Rx path")
added an extra argument to function xdp_rxq_info_reg and commit
d57e57d0cd ("dpaa_eth: add XDP_TX support") didn't know about that
extra argument.
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Link: https://lore.kernel.org/r/20201203144343.790719-1-anders.roxell@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-12-03
The main changes are:
1) Support BTF in kernel modules, from Andrii.
2) Introduce preferred busy-polling, from Björn.
3) bpf_ima_inode_hash() and bpf_bprm_opts_set() helpers, from KP Singh.
4) Memcg-based memory accounting for bpf objects, from Roman.
5) Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks, from Stanislav.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (118 commits)
selftests/bpf: Fix invalid use of strncat in test_sockmap
libbpf: Use memcpy instead of strncpy to please GCC
selftests/bpf: Add fentry/fexit/fmod_ret selftest for kernel module
selftests/bpf: Add tp_btf CO-RE reloc test for modules
libbpf: Support attachment of BPF tracing programs to kernel modules
libbpf: Factor out low-level BPF program loading helper
bpf: Allow to specify kernel module BTFs when attaching BPF programs
bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier
selftests/bpf: Add CO-RE relocs selftest relying on kernel module BTF
selftests/bpf: Add support for marking sub-tests as skipped
selftests/bpf: Add bpf_testmod kernel module for testing
libbpf: Add kernel module BTF support for CO-RE relocations
libbpf: Refactor CO-RE relocs to not assume a single BTF object
libbpf: Add internal helper to load BTF data by FD
bpf: Keep module's btf_data_size intact after load
bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address()
selftests/bpf: Add Userspace tests for TCP_WINDOW_CLAMP
bpf: Adds support for setting window clamp
samples/bpf: Fix spelling mistake "recieving" -> "receiving"
bpf: Fix cold build of test_progs-no_alu32
...
====================
Link: https://lore.kernel.org/r/20201204021936.85653-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
strncat()'s third argument is how many bytes will be added *in addition* to
already existing bytes in destination. Plus extra zero byte will be added
after that. So existing use in test_sockmap has many opportunities to overflow
the string and cause memory corruptions. And in this case, GCC complains for
a good reason.
Fixes: 16962b2404 ("bpf: sockmap, add selftests")
Fixes: 73563aa3d9 ("selftests/bpf: test_sockmap, print additional test options")
Fixes: 1ade9abadf ("bpf: test_sockmap, add options for msg_pop_data() helper")
Fixes: 463bac5f1c ("bpf, selftests: Add test for ktls with skb bpf ingress policy")
Fixes: e9dd904708 ("bpf: add tls support for testing in test_sockmap")
Fixes: 753fb2ee09 ("bpf: sockmap, add msg_peek tests to test_sockmap")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203235440.2302137-2-andrii@kernel.org
Some versions of GCC are really nit-picky about strncpy() use. Use memcpy(),
as they are pretty much equivalent for the case of fixed length strings.
Fixes: e459f49b43 ("libbpf: Separate XDP program load with xsk socket creation")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203235440.2302137-1-andrii@kernel.org
Andrii Nakryiko says:
====================
This patch sets extends kernel and libbpf with support for attaching
BTF-powered raw tracepoint (tp_btf) and tracing (fentry/fexit/fmod_ret/lsm)
BPF programs to BPF hooks defined in kernel modules. As part of that, libbpf
now supports performing CO-RE relocations against types in kernel module BTFs,
in addition to existing vmlinux BTF support.
Kernel UAPI for BPF_PROG_LOAD now allows to specify kernel module (or vmlinux)
BTF object FD in attach_btf_obj_fd field, aliased to attach_prog_fd. This is
used to identify which BTF object needs to be used for finding BTF type by
provided attach_btf_id.
This patch set also sets up a convenient and fully-controlled custom kernel
module (called "bpf_testmod"), that is a predictable playground for all the
BPF selftests, that rely on module BTFs. Currently pahole doesn't generate
BTF_KIND_FUNC info for ftrace-able static functions in kernel modules, so
expose traced function in bpf_sidecar.ko. Once pahole is enhanced, we can go
back to static function.
From end user perspective there are no extra actions that need to happen.
Libbpf will continue searching across all kernel module BTFs, if desired
attach BTF type is not found in vmlinux. That way it doesn't matter if BPF
hook that user is trying to attach to is built into vmlinux image or is
loaded in kernel module.
v5->v6:
- move btf_put() back to syscall.c (kernel test robot);
- added close(fd) in patch #5 (John);
v4->v5:
- use FD to specify BTF object (Alexei);
- move prog->aux->attach_btf putting into bpf_prog_free() for consistency
with putting prog->aux->dst_prog;
- fix BTF FD leak(s) in libbpf;
v3->v4:
- merge together patch sets [0] and [1];
- avoid increasing bpf_reg_state by reordering fields (Alexei);
- preserve btf_data_size in struct module;
v2->v3:
- fix subtle uninitialized variable use in BTF ID iteration code;
v1->v2:
- module_put() inside preempt_disable() region (Alexei);
- bpf_sidecar -> bpf_testmod rename (Alexei);
- test_progs more relaxed handling of bpf_testmod;
- test_progs marks skipped sub-tests properly as SKIP now.
[0] https://patchwork.kernel.org/project/netdevbpf/list/?series=393677&state=*
[1] https://patchwork.kernel.org/project/netdevbpf/list/?series=393679&state=*
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add another CO-RE relocation test for kernel module relocations. This time for
tp_btf with direct memory reads.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-14-andrii@kernel.org
Teach libbpf to search for BTF types in kernel modules for tracing BPF
programs. This allows attachment of raw_tp/fentry/fexit/fmod_ret/etc BPF
program types to tracepoints and functions in kernel modules.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-13-andrii@kernel.org
Refactor low-level API for BPF program loading to not rely on public API
types. This allows painless extension without constant efforts to cleverly not
break backwards compatibility.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-12-andrii@kernel.org
Add ability for user-space programs to specify non-vmlinux BTF when attaching
BTF-powered BPF programs: raw_tp, fentry/fexit/fmod_ret, LSM, etc. For this,
attach_prog_fd (now with the alias name attach_btf_obj_fd) should specify FD
of a module or vmlinux BTF object. For backwards compatibility reasons,
0 denotes vmlinux BTF. Only kernel BTF (vmlinux or module) can be specified.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-11-andrii@kernel.org
Remove a permeating assumption thoughout BPF verifier of vmlinux BTF. Instead,
wherever BTF type IDs are involved, also track the instance of struct btf that
goes along with the type ID. This allows to gradually add support for kernel
module BTFs and using/tracking module types across BPF helper calls and
registers.
This patch also renames btf_id() function to btf_obj_id() to minimize naming
clash with using btf_id to denote BTF *type* ID, rather than BTF *object*'s ID.
Also, altough btf_vmlinux can't get destructed and thus doesn't need
refcounting, module BTFs need that, so apply BTF refcounting universally when
BPF program is using BTF-powered attachment (tp_btf, fentry/fexit, etc). This
makes for simpler clean up code.
Now that BTF type ID is not enough to uniquely identify a BTF type, extend BPF
trampoline key to include BTF object ID. To differentiate that from target
program BPF ID, set 31st bit of type ID. BTF type IDs (at least currently) are
not allowed to take full 32 bits, so there is no danger of confusing that bit
with a valid BTF type ID.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-10-andrii@kernel.org
Add a self-tests validating libbpf is able to perform CO-RE relocations
against the type defined in kernel module BTF. if bpf_testmod.o is not
supported by the kernel (e.g., due to version mismatch), skip tests, instead
of failing.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-9-andrii@kernel.org
Previously skipped sub-tests would be counted as passing with ":OK" appened
in the log. Change that to be accounted as ":SKIP".
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-8-andrii@kernel.org
Add bpf_testmod module, which is conceptually out-of-tree module and provides
ways for selftests/bpf to test various kernel module-related functionality:
raw tracepoint, fentry/fexit/fmod_ret, etc. This module will be auto-loaded by
test_progs test runner and expected by some of selftests to be present and
loaded.
Pahole currently isn't able to generate BTF for static functions in kernel
modules, so make sure traced function is global.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-7-andrii@kernel.org
Teach libbpf to search for candidate types for CO-RE relocations across kernel
modules BTFs, in addition to vmlinux BTF. If at least one candidate type is
found in vmlinux BTF, kernel module BTFs are not iterated. If vmlinux BTF has
no matching candidates, then find all kernel module BTFs and search for all
matching candidates across all of them.
Kernel's support for module BTFs are inferred from the support for BTF name
pointer in BPF UAPI.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-6-andrii@kernel.org
Refactor CO-RE relocation candidate search to not expect a single BTF, rather
return all candidate types with their corresponding BTF objects. This will
allow to extend CO-RE relocations to accommodate kernel module BTFs.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-5-andrii@kernel.org
Add a btf_get_from_fd() helper, which constructs struct btf from in-kernel BTF
data by FD. This is used for loading module BTFs.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-4-andrii@kernel.org
Having real btf_data_size stored in struct module is benefitial to quickly
determine which kernel modules have associated BTF object and which don't.
There is no harm in keeping this info, as opposed to keeping invalid pointer.
Fixes: 607c543f93 ("bpf: Sanitize BTF data pointer after module is loaded")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-3-andrii@kernel.org
__module_address() needs to be called with preemption disabled or with
module_mutex taken. preempt_disable() is enough for read-only uses, which is
what this fix does. Also, module_put() does internal check for NULL, so drop
it as well.
Fixes: a38d1107f9 ("bpf: support raw tracepoints in modules")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-2-andrii@kernel.org
Prankur gupta says:
====================
This patch contains support to set tcp window_field field from bpf setsockops.
v2: Used TCP_WINDOW_CLAMP setsockopt logic for bpf_setsockopt (review comment addressed)
v3: Created a common function for duplicated code (review comment addressed)
v4: Removing logic to pass struct sock and struct tcp_sock together (review comment addressed)
====================
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adds a new bpf_setsockopt for TCP sockets, TCP_BPF_WINDOW_CLAMP,
which sets the maximum receiver window size. It will be useful for
limiting receiver window based on RTT.
Signed-off-by: Prankur gupta <prankgup@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201202213152.435886-2-prankgup@fb.com
Florian Westphal says:
====================
mptcp: reject invalid mp_join requests right away
At the moment MPTCP can detect an invalid join request (invalid token,
max number of subflows reached, and so on) right away but cannot reject
the connection until the 3WHS has completed.
Instead the connection will complete and the subflow is reset afterwards.
To send the reset most information is already available, but we don't have
good spot where the reset could be sent:
1. The ->init_req callback is too early and also doesn't allow to return an
error that could be used to inform the TCP stack that the SYN should be
dropped.
2. The ->route_req callback lacks the skb needed to send a reset.
3. The ->send_synack callback is the best fit from the available hooks,
but its called after the request socket has been inserted into the queue
already. This means we'd have to remove it again right away.
From a technical point of view, the second hook would be best:
1. Its before insertion into listener queue.
2. If it returns NULL TCP will drop the packet for us.
Problem is that we'd have to pass the skb to the function just for MPTCP.
Paolo suggested to merge init_req and route_req callbacks instead:
This makes all info available to MPTCP -- a return value of NULL drops the
packet and MPTCP can send the reset if needed.
Because 'route_req' has a 'const struct sock *', this means either removal
of const qualifier, or a bit of code churn to pass 'const' in security land.
This does the latter; I did not find any spots that need write access to struct
sock.
To recap, the two alternatives are:
1. Solve it entirely in MPTCP: use the ->send_synack callback to
unlink the request socket from the listener & drop it.
2. Avoid 'security' churn by removing the const qualifier.
====================
Link: https://lore.kernel.org/r/20201130153631.21872-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
RFC 8684 says:
If the token is unknown or the host wants to refuse subflow establishment
(for example, due to a limit on the number of subflows it will permit),
the receiver will send back a reset (RST) signal, analogous to an unknown
port in TCP, containing an MP_TCPRST option (Section 3.6) with an
"MPTCP specific error" reason code.
mptcp-next doesn't support MP_TCPRST yet, this can be added in another
change.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The Multipath-TCP standard (RFC 8684) says that an MPTCP host should send
a TCP reset if the token in a MP_JOIN request is unknown.
At this time we don't do this, the 3whs completes and the 'new subflow'
is reset afterwards. There are two ways to allow MPTCP to send the
reset.
1. override 'send_synack' callback and emit the rst from there.
The drawback is that the request socket gets inserted into the
listeners queue just to get removed again right away.
2. Send the reset from the 'route_req' function instead.
This avoids the 'add&remove request socket', but route_req lacks the
skb that is required to send the TCP reset.
Instead of just adding the skb to that function for MPTCP sake alone,
Paolo suggested to merge init_req and route_req functions.
This saves one indirection from syn processing path and provides the skb
to the merged function at the same time.
'send reset on unknown mptcp join token' is added in next patch.
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A followup change to tcp_request_sock_op would have to drop the 'const'
qualifier from the 'route_req' function as the
'security_inet_conn_request' call is moved there - and that function
expects a 'struct sock *'.
However, it turns out its also possible to add a const qualifier to
security_inet_conn_request instead.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This object lives inside the trunner output dir,
i.e. tools/testing/selftests/bpf/no_alu32/btf_data.o
At some point it gets copied into the parent directory during another
part of the build, but that doesn't happen when building
test_progs-no_alu32 from clean.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20201203120850.859170-1-jackmanb@google.com
I've seen a situation, where a process that's under pprof constantly
generates SIGPROF which prevents program loading indefinitely.
The right thing to do probably is to disable signals in the upper
layers while loading, but it still would be nice to get some error from
libbpf instead of an endless loop.
Let's add some small retry limit to the program loading:
try loading the program 5 (arbitrary) times and give up.
v2:
* 10 -> 5 retires (Andrii Nakryiko)
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201202231332.3923644-1-sdf@google.com
- fix logical vs physical CPU address confusion in PCI code
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Merge tag 's390-5.10-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Heiko Carstens:
"One commit is fixing lockdep irq state tracing which broke with -rc6.
The other one fixes logical vs physical CPU address mixup in our PCI
code.
Summary:
- fix lockdep irq state tracing
- fix logical vs physical CPU address confusion in PCI code"
* tag 's390-5.10-6' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: fix irq state tracing
s390/pci: fix CPU address in MSI for directed IRQ
When we added sanitising of map names before loading programs to libbpf, we
still allowed periods in the name. While the kernel will accept these for
the map names themselves, they are not allowed in file names when pinning
maps. This means that bpf_object__pin_maps() will fail if called on an
object that contains internal maps (such as sections .rodata).
Fix this by replacing periods with underscores when constructing map pin
paths. This only affects the paths generated by libbpf when
bpf_object__pin_maps() is called with a path argument. Any pin paths set
by bpf_map__set_pin_path() are unaffected, and it will still be up to the
caller to avoid invalid characters in those.
Fixes: 113e6b7e15 ("libbpf: Sanitise internal map names so they are not rejected by the kernel")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201203093306.107676-1-toke@redhat.com
Before this patch, a program with unspecified type
(BPF_PROG_TYPE_UNSPEC) would be passed to the BPF syscall, only to have
the kernel reject it with an opaque invalid argument error. This patch
makes libbpf reject such programs with a nicer error message - in
particular libbpf now tries to diagnose bad ELF section names at both
open time and load time.
Signed-off-by: Andrei Matei <andreimatei1@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20201203043410.59699-1-andreimatei1@gmail.com
