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2018-09-18samples/bpf: remove duplicated includesYueHaibing1-1/+0
Remove duplicated includes. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-16samples: bpf: ensure that we don't load over MAX_PROGS programsDan Carpenter1-0/+3
I can't see that we check prog_cnt to ensure it doesn't go over MAX_PROGS. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-14samples: bpf: include bpf/bpf.h instead of local libbpf.hJakub Kicinski1-1/+1
There are two files in the tree called libbpf.h which is becoming problematic. Most samples don't actually need the local libbpf.h they simply include it to get to bpf/bpf.h. Include bpf/bpf.h directly instead. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-11samples: bpf: rename struct bpf_map_def to avoid conflict with libbpfJakub Kicinski1-5/+5
Both tools/lib/bpf/libbpf.h and samples/bpf/bpf_load.h define their own version of struct bpf_map_def. The version in bpf_load.h has more fields. libbpf does not support inner maps and its definition of struct bpf_map_def lacks the related fields. Rename the definition in bpf_load.h (samples/bpf) to avoid conflicts. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-29samples/bpf: fix kprobe attachment issue on x64Yonghong Song1-8/+26
Commit d5a00528b58c ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()") renamed a lot of syscall function sys_*() to __x64_sys_*(). This caused several kprobe based samples/bpf tests failing. This patch fixed the problem in bpf_load.c. For x86_64 architecture, function name __x64_sys_*() will be first used for kprobe event creation. If the creation is successful, it will be used. Otherwise, function name sys_*() will be used for kprobe event creation. Fixes: d5a00528b58c ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29samples/bpf: move common-purpose trace functions to selftestsYonghong Song1-63/+0
There is no functionality change in this patch. The common-purpose trace functions, including perf_event polling and ksym lookup, are moved from trace_output_user.c and bpf_load.c to selftests/bpf/trace_helpers.c so that these function can be reused later in selftests. Acked-by: Alexei Starovoitov <ast@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-27samples, bpf: remove redundant ret assignment in bpf_load_program()Wang Sheng-Hui1-2/+0
2 redundant ret assignments removed: * 'ret = 1' before the logic 'if (data_maps)', and if any errors jump to label 'done'. No 'ret = 1' needed before the error jump. * After the '/* load programs */' part, if everything goes well, then the BPF code will be loaded and 'ret' set to 0 by load_and_attach(). If something goes wrong, 'ret' set to none-O, the redundant 'ret = 0' after the for clause will make the error skipped. For example, if some BPF code cannot provide supported program types in ELF SEC("unknown"), the for clause will not call load_and_attach() to load the BPF code. 1 should be returned to callees instead of 0. Signed-off-by: Wang Sheng-Hui <shhuiw@foxmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-28samples/bpf: raw tracepoint testAlexei Starovoitov1-0/+14
add empty raw_tracepoint bpf program to test overhead similar to kprobe and traditional tracepoint tests Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-19bpf: sockmap sample, add option to attach SK_MSG programJohn Fastabend1-2/+6
Add sockmap option to use SK_MSG program types. 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>
2018-02-02samples/bpf: use bpf_set_link_xdp_fdEric Leblond1-102/+0
Use bpf_set_link_xdp_fd instead of set_link_xdp_fd to remove some code duplication and benefit of netlink ext ack errors message. Signed-off-by: Eric Leblond <eric@regit.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-01samples/bpf: add error checking for perf ioctl calls in bpf loaderYonghong Song1-2/+12
load_bpf_file() should fail if ioctl with command PERF_EVENT_IOC_ENABLE and PERF_EVENT_IOC_SET_BPF fails. When they do fail, proper error messages are printed. With this change, the below "syscall_tp" run shows that the maximum number of bpf progs attaching to the same perf tracepoint is indeed enforced. $ ./syscall_tp -i 64 prog #0: map ids 4 5 ... prog #63: map ids 382 383 $ ./syscall_tp -i 65 prog #0: map ids 4 5 ... prog #64: map ids 388 389 ioctl PERF_EVENT_IOC_SET_BPF failed err Argument list too long Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-11-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-29bpf: libbpf: Provide basic API support to specify BPF obj nameMartin KaFai Lau1-0/+2
This patch extends the libbpf to provide API support to allow specifying BPF object name. In tools/lib/bpf/libbpf, the C symbol of the function and the map is used. Regarding section name, all maps are under the same section named "maps". Hence, section name is not a good choice for map's name. To be consistent with map, bpf_prog also follows and uses its function symbol as the prog's name. This patch adds logic to collect function's symbols in libbpf. There is existing codes to collect the map's symbols and no change is needed. The bpf_load_program_name() and bpf_map_create_name() are added to take the name argument. For the other bpf_map_create_xxx() variants, a name argument is directly added to them. In samples/bpf, bpf_load.c in particular, the symbol is also used as the map's name and the map symbols has already been collected in the existing code. For bpf_prog, bpf_load.c does not collect the function symbol name. We can consider to collect them later if there is a need to continue supporting the bpf_load.c. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-19bpf: Allow numa selection in INNER_LRU_HASH_PREALLOC test of map_perf_testMartin KaFai Lau1-8/+13
This patch makes the needed changes to allow each process of the INNER_LRU_HASH_PREALLOC test to provide its numa node id when creating the lru map. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-16bpf: sockmap sample programJohn Fastabend1-2/+6
This program binds a program to a cgroup and then matches hard coded IP addresses and adds these to a sockmap. This will receive messages from the backend and send them to the client. client:X <---> frontend:10000 client:X <---> backend:10001 To keep things simple this is only designed for 1:1 connections using hard coded values. A more complete example would allow many backends and clients. To run, # sockmap <cgroup2_dir> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-05bpf: fix return in load_bpf_fileLawrence Brakmo1-2/+6
The function load_bpf_file ignores the return value of load_and_attach(), so even if load_and_attach() returns an error, load_bpf_file() will return 0. Now, load_bpf_file() can call load_and_attach() multiple times and some can succeed and some could fail. I think the correct behavor is to return error on the first failed load_and_attach(). v2: Added missing SOB Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01bpf: BPF support for sock_opsLawrence Brakmo1-3/+10
Created a new BPF program type, BPF_PROG_TYPE_SOCK_OPS, and a corresponding struct that allows BPF programs of this type to access some of the socket's fields (such as IP addresses, ports, etc.). It uses the existing bpf cgroups infrastructure so the programs can be attached per cgroup with full inheritance support. The program will be called at appropriate times to set relevant connections parameters such as buffer sizes, SYN and SYN-ACK RTOs, etc., based on connection information such as IP addresses, port numbers, etc. Alghough there are already 3 mechanisms to set parameters (sysctls, route metrics and setsockopts), this new mechanism provides some distinct advantages. Unlike sysctls, it can set parameters per connection. In contrast to route metrics, it can also use port numbers and information provided by a user level program. In addition, it could set parameters probabilistically for evaluation purposes (i.e. do something different on 10% of the flows and compare results with the other 90% of the flows). Also, in cases where IPv6 addresses contain geographic information, the rules to make changes based on the distance (or RTT) between the hosts are much easier than route metric rules and can be global. Finally, unlike setsockopt, it oes not require application changes and it can be updated easily at any time. Although the bpf cgroup framework already contains a sock related program type (BPF_PROG_TYPE_CGROUP_SOCK), I created the new type (BPF_PROG_TYPE_SOCK_OPS) beccause the existing type expects to be called only once during the connections's lifetime. In contrast, the new program type will be called multiple times from different places in the network stack code. For example, before sending SYN and SYN-ACKs to set an appropriate timeout, when the connection is established to set congestion control, etc. As a result it has "op" field to specify the type of operation requested. The purpose of this new program type is to simplify setting connection parameters, such as buffer sizes, TCP's SYN RTO, etc. For example, it is easy to use facebook's internal IPv6 addresses to determine if both hosts of a connection are in the same datacenter. Therefore, it is easy to write a BPF program to choose a small SYN RTO value when both hosts are in the same datacenter. This patch only contains the framework to support the new BPF program type, following patches add the functionality to set various connection parameters. This patch defines a new BPF program type: BPF_PROG_TYPE_SOCKET_OPS and a new bpf syscall command to load a new program of this type: BPF_PROG_LOAD_SOCKET_OPS. Two new corresponding structs (one for the kernel one for the user/BPF program): /* kernel version */ struct bpf_sock_ops_kern { struct sock *sk; __u32 op; union { __u32 reply; __u32 replylong[4]; }; }; /* user version * Some fields are in network byte order reflecting the sock struct * Use the bpf_ntohl helper macro in samples/bpf/bpf_endian.h to * convert them to host byte order. */ struct bpf_sock_ops { __u32 op; union { __u32 reply; __u32 replylong[4]; }; __u32 family; __u32 remote_ip4; /* In network byte order */ __u32 local_ip4; /* In network byte order */ __u32 remote_ip6[4]; /* In network byte order */ __u32 local_ip6[4]; /* In network byte order */ __u32 remote_port; /* In network byte order */ __u32 local_port; /* In host byte horder */ }; Currently there are two types of ops. The first type expects the BPF program to return a value which is then used by the caller (or a negative value to indicate the operation is not supported). The second type expects state changes to be done by the BPF program, for example through a setsockopt BPF helper function, and they ignore the return value. The reply fields of the bpf_sockt_ops struct are there in case a bpf program needs to return a value larger than an integer. Signed-off-by: Lawrence Brakmo <brakmo@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-31samples/bpf: bpf_load.c order of prog_fd[] should correspond with ELF orderJesper Dangaard Brouer1-14/+5
An eBPF ELF file generated with LLVM can contain several program section, which can be used for bpf tail calls. The bpf prog file descriptors are accessible via array prog_fd[]. At-least XDP samples assume ordering, and uses prog_fd[0] is the main XDP program to attach. The actual order of array prog_fd[] depend on whether or not a bpf program section is referencing any maps or not. Not using a map result in being loaded/processed after all other prog section. Thus, this can lead to some very strange and hard to debug situation, as the user can only see a FD and cannot correlated that with the ELF section name. The fix is rather simple, and even removes duplicate memcmp code. Simply load program sections as the last step, instead of load_and_attach while processing the relocation section. When working with tail calls, it become even more essential that the order of prog_fd[] is consistant, like the current dependency of the map_fd[] order. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-03samples/bpf: load_bpf.c make callback fixup more flexibleJesper Dangaard Brouer1-9/+8
Do this change before others start to use this callback. Change map_perf_test_user.c which seems to be the only user. This patch extends capabilities of commit 9fd63d05f3e8 ("bpf: Allow bpf sample programs (*_user.c) to change bpf_map_def"). Give fixup callback access to struct bpf_map_data, instead of only stuct bpf_map_def. This add flexibility to allow userspace to reassign the map file descriptor. This is very useful when wanting to share maps between several bpf programs. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-03samples/bpf: make bpf_load.c code compatible with ELF maps section changesJesper Dangaard Brouer1-69/+155
This patch does proper parsing of the ELF "maps" section, in-order to be both backwards and forwards compatible with changes to the map definition struct bpf_map_def, which gets compiled into the ELF file. The assumption is that new features with value zero, means that they are not in-use. For backward compatibility where loading an ELF file with a smaller struct bpf_map_def, only copy objects ELF size, leaving rest of loaders struct zero. For forward compatibility where ELF file have a larger struct bpf_map_def, only copy loaders own struct size and verify that rest of the larger struct is zero, assuming this means the newer feature was not activated, thus it should be safe for this older loader to load this newer ELF file. Fixes: fb30d4b71214 ("bpf: Add tests for map-in-map") Fixes: 409526bea3c3 ("samples/bpf: bpf_load.c detect and abort if ELF maps section size is wrong") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-01samples/bpf: fix SKB_MODE flag to be a 32-bit unsigned intJesper Dangaard Brouer1-1/+2
The kernel side of XDP_FLAGS_SKB_MODE is unsigned, and the rtnetlink IFLA_XDP_FLAGS is defined as NLA_U32. Thus, userspace programs under samples/bpf/ should use the correct type. Fixes: 3993f2cb983b ("samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnel") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-30samples/bpf: bpf_load.c detect and abort if ELF maps section size is wrongJesper Dangaard Brouer1-9/+31
The struct bpf_map_def was extended in commit fb30d4b71214 ("bpf: Add tests for map-in-map") with member unsigned int inner_map_idx. This changed the size of the maps section in the generated ELF _kern.o files. Unfortunately the loader in bpf_load.c does not detect or handle this. Thus, older _kern.o files became incompatible, and caused hard-to-debug errors where the syscall validation rejected BPF_MAP_CREATE request. This patch only detect the situation and aborts load_bpf_file(). It also add code comments warning people that read this loader for inspiration for these pitfalls. Fixes: fb30d4b71214 ("bpf: Add tests for map-in-map") Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-27samples/bpf: Add support for SKB_MODE to xdp1 and xdp_tx_iptunnelDavid Ahern1-3/+16
Add option to xdp1 and xdp_tx_iptunnel to insert xdp program in SKB_MODE: - update set_link_xdp_fd to take a flags argument that is added to the RTM_SETLINK message - Add -S option to xdp1 and xdp_tx_iptunnel user code. When passed in XDP_FLAGS_SKB_MODE is set in the flags arg passed to set_link_xdp_fd Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-17bpf: Allow bpf sample programs (*_user.c) to change bpf_map_defMartin KaFai Lau1-18/+96
The current bpf_map_def is statically defined during compile time. This patch allows the *_user.c program to change it during runtime. It is done by adding load_bpf_file_fixup_map() which takes a callback. The callback will be called before creating each map so that it has a chance to modify the bpf_map_def. The current usecase is to change max_entries in map_perf_test. It is interesting to test with a much bigger map size in some cases (e.g. the following patch on bpf_lru_map.c). However, it is hard to find one size to fit all testing environment. Hence, it is handy to take the max_entries as a cmdline arg and then configure the bpf_map_def during runtime. This patch adds two cmdline args. One is to configure the map's max_entries. Another is to configure the max_cnt which controls how many times a syscall is called. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-22bpf: Add tests for map-in-mapMartin KaFai Lau1-5/+17
Test cases for array of maps and hash of maps. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-13samples/bpf: Reset global variablesMickaël Salaün1-0/+5
Before loading a new ELF, clean previous kernel version, license and processed sections. Signed-off-by: Mickaël Salaün <mic@digikod.net> Acked-by: Joe Stringer <joe@ovn.org> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170208202744.16274-3-mic@digikod.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-13samples/bpf: Ignore already processed ELF sectionsMickaël Salaün1-0/+2
Add a missing check for the map fixup loop. Signed-off-by: Mickaël Salaün <mic@digikod.net> Acked-by: Joe Stringer <joe@ovn.org> Acked-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20170208202744.16274-2-mic@digikod.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-20samples/bpf: Remove perf_event_open() declarationJoe Stringer1-1/+2
This declaration was made in samples/bpf/libbpf.c for convenience, but there's already one in tools/perf/perf-sys.h. Reuse that one. Committer notes: Testing it: $ make -j4 O=../build/v4.9.0-rc8+ samples/bpf/ make[1]: Entering directory '/home/build/v4.9.0-rc8+' CHK include/config/kernel.release GEN ./Makefile CHK include/generated/uapi/linux/version.h Using /home/acme/git/linux as source for kernel CHK include/generated/utsrelease.h CHK include/generated/timeconst.h CHK include/generated/bounds.h CHK include/generated/asm-offsets.h CALL /home/acme/git/linux/scripts/checksyscalls.sh HOSTCC samples/bpf/test_verifier.o HOSTCC samples/bpf/libbpf.o HOSTCC samples/bpf/../../tools/lib/bpf/bpf.o HOSTCC samples/bpf/test_maps.o HOSTCC samples/bpf/sock_example.o HOSTCC samples/bpf/bpf_load.o <SNIP> HOSTLD samples/bpf/trace_event HOSTLD samples/bpf/sampleip HOSTLD samples/bpf/tc_l2_redirect make[1]: Leaving directory '/home/build/v4.9.0-rc8+' $ Also tested the offwaketime resulting from the rebuild, seems to work as before. Signed-off-by: Joe Stringer <joe@ovn.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/20161209024620.31660-7-joe@ovn.org [ Use -I$(srctree)/tools/lib/ to support out of source code tree builds ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-20samples/bpf: Switch over to libbpfJoe Stringer1-1/+2
Now that libbpf under tools/lib/bpf/* is synced with the version from samples/bpf, we can get rid most of the libbpf library here. Committer notes: Built it in a docker fedora rawhide container and ran it in the f25 host, seems to work just like it did before this patch, i.e. the switch to tools/lib/bpf/ doesn't seem to have introduced problems and Joe said he tested it with all the entries in samples/bpf/ and other code he found: [root@f5065a7d6272 linux]# make -j4 O=/tmp/build/linux headers_install <SNIP> [root@f5065a7d6272 linux]# rm -rf /tmp/build/linux/samples/bpf/ [root@f5065a7d6272 linux]# make -j4 O=/tmp/build/linux samples/bpf/ make[1]: Entering directory '/tmp/build/linux' CHK include/config/kernel.release HOSTCC scripts/basic/fixdep GEN ./Makefile CHK include/generated/uapi/linux/version.h Using /git/linux as source for kernel CHK include/generated/utsrelease.h HOSTCC scripts/basic/bin2c HOSTCC arch/x86/tools/relocs_32.o HOSTCC arch/x86/tools/relocs_64.o LD samples/bpf/built-in.o <SNIP> HOSTCC samples/bpf/fds_example.o HOSTCC samples/bpf/sockex1_user.o /git/linux/samples/bpf/fds_example.c: In function 'bpf_prog_create': /git/linux/samples/bpf/fds_example.c:63:6: warning: passing argument 2 of 'bpf_load_program' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers] insns, insns_cnt, "GPL", 0, ^~~~~ In file included from /git/linux/samples/bpf/libbpf.h:5:0, from /git/linux/samples/bpf/bpf_load.h:4, from /git/linux/samples/bpf/fds_example.c:15: /git/linux/tools/lib/bpf/bpf.h:31:5: note: expected 'struct bpf_insn *' but argument is of type 'const struct bpf_insn *' int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns, ^~~~~~~~~~~~~~~~ HOSTCC samples/bpf/sockex2_user.o <SNIP> HOSTCC samples/bpf/xdp_tx_iptunnel_user.o clang -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/6.2.1/include -I/git/linux/arch/x86/include -I./arch/x86/include/generated/uapi -I./arch/x86/include/generated -I/git/linux/include -I./include -I/git/linux/arch/x86/include/uapi -I/git/linux/include/uapi -I./include/generated/uapi -include /git/linux/include/linux/kconfig.h \ -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \ -Wno-compare-distinct-pointer-types \ -Wno-gnu-variable-sized-type-not-at-end \ -Wno-address-of-packed-member -Wno-tautological-compare \ -O2 -emit-llvm -c /git/linux/samples/bpf/sockex1_kern.c -o -| llc -march=bpf -filetype=obj -o samples/bpf/sockex1_kern.o HOSTLD samples/bpf/tc_l2_redirect <SNIP> HOSTLD samples/bpf/lwt_len_hist HOSTLD samples/bpf/xdp_tx_iptunnel make[1]: Leaving directory '/tmp/build/linux' [root@f5065a7d6272 linux]# And then, in the host: [root@jouet bpf]# mount | grep "docker.*devicemapper\/" /dev/mapper/docker-253:0-1705076-9bd8aa1e0af33adce89ff42090847868ca676932878942be53941a06ec5923f9 on /var/lib/docker/devicemapper/mnt/9bd8aa1e0af33adce89ff42090847868ca676932878942be53941a06ec5923f9 type xfs (rw,relatime,context="system_u:object_r:container_file_t:s0:c73,c276",nouuid,attr2,inode64,sunit=1024,swidth=1024,noquota) [root@jouet bpf]# cd /var/lib/docker/devicemapper/mnt/9bd8aa1e0af33adce89ff42090847868ca676932878942be53941a06ec5923f9/rootfs/tmp/build/linux/samples/bpf/ [root@jouet bpf]# file offwaketime offwaketime: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=f423d171e0487b2f802b6a792657f0f3c8f6d155, not stripped [root@jouet bpf]# readelf -SW offwaketime offwaketime offwaketime_kern.o offwaketime_user.o [root@jouet bpf]# readelf -SW offwaketime_kern.o There are 11 section headers, starting at offset 0x700: Section Headers: [Nr] Name Type Address Off Size ES Flg Lk Inf Al [ 0] NULL 0000000000000000 000000 000000 00 0 0 0 [ 1] .strtab STRTAB 0000000000000000 000658 0000a8 00 0 0 1 [ 2] .text PROGBITS 0000000000000000 000040 000000 00 AX 0 0 4 [ 3] kprobe/try_to_wake_up PROGBITS 0000000000000000 000040 0000d8 00 AX 0 0 8 [ 4] .relkprobe/try_to_wake_up REL 0000000000000000 0005a8 000020 10 10 3 8 [ 5] tracepoint/sched/sched_switch PROGBITS 0000000000000000 000118 000318 00 AX 0 0 8 [ 6] .reltracepoint/sched/sched_switch REL 0000000000000000 0005c8 000090 10 10 5 8 [ 7] maps PROGBITS 0000000000000000 000430 000050 00 WA 0 0 4 [ 8] license PROGBITS 0000000000000000 000480 000004 00 WA 0 0 1 [ 9] version PROGBITS 0000000000000000 000484 000004 00 WA 0 0 4 [10] .symtab SYMTAB 0000000000000000 000488 000120 18 1 4 8 Key to Flags: W (write), A (alloc), X (execute), M (merge), S (strings) I (info), L (link order), G (group), T (TLS), E (exclude), x (unknown) O (extra OS processing required) o (OS specific), p (processor specific) [root@jouet bpf]# ./offwaketime | head -3 qemu-system-x86;entry_SYSCALL_64_fastpath;sys_ppoll;do_sys_poll;poll_schedule_timeout;schedule_hrtimeout_range;schedule_hrtimeout_range_clock;schedule;__schedule;-;try_to_wake_up;hrtimer_wakeup;__hrtimer_run_queues;hrtimer_interrupt;local_apic_timer_interrupt;smp_apic_timer_interrupt;__irqentry_text_start;cpuidle_enter_state;cpuidle_enter;call_cpuidle;cpu_startup_entry;rest_init;start_kernel;x86_64_start_reservations;x86_64_start_kernel;start_cpu;;swapper/0 4 firefox;entry_SYSCALL_64_fastpath;sys_poll;do_sys_poll;poll_schedule_timeout;schedule_hrtimeout_range;schedule_hrtimeout_range_clock;schedule;__schedule;-;try_to_wake_up;pollwake;__wake_up_common;__wake_up_sync_key;pipe_write;__vfs_write;vfs_write;sys_write;entry_SYSCALL_64_fastpath;;Timer 1 swapper/2;start_cpu;start_secondary;cpu_startup_entry;schedule_preempt_disabled;schedule;__schedule;-;---;; 61 [root@jouet bpf]# Signed-off-by: Joe Stringer <joe@ovn.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Wang Nan <wangnan0@huawei.com> Cc: netdev@vger.kernel.org Link: https://github.com/joestringer/linux/commit/5c40f54a52b1f437123c81e21873f4b4b1f9bd55.patch Link: http://lkml.kernel.org/n/tip-xr8twtx7sjh5821g8qw47yxk@git.kernel.org [ Use -I$(srctree)/tools/lib/ to support out of source code tree builds, as noticed by Wang Nan ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-15samples/bpf: Make samples more libbpf-centricJoe Stringer1-4/+13
Switch all of the sample code to use the function names from tools/lib/bpf so that they're consistent with that, and to declare their own log buffers. This allow the next commit to be purely devoted to getting rid of the duplicate library in samples/bpf. Committer notes: Testing it: On a fedora rawhide container, with clang/llvm 3.9, sharing the host linux kernel git tree: # make O=/tmp/build/linux/ headers_install # make O=/tmp/build/linux -C samples/bpf/ Since I forgot to make it privileged, just tested it outside the container, using what it generated: # uname -a Linux jouet 4.9.0-rc8+ #1 SMP Mon Dec 12 11:20:49 BRT 2016 x86_64 x86_64 x86_64 GNU/Linux # cd /var/lib/docker/devicemapper/mnt/c43e09a53ff56c86a07baf79847f00e2cc2a17a1e2220e1adbf8cbc62734feda/rootfs/tmp/build/linux/samples/bpf/ # ls -la offwaketime -rwxr-xr-x. 1 root root 24200 Dec 15 12:19 offwaketime # file offwaketime offwaketime: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=c940d3f127d5e66cdd680e42d885cb0b64f8a0e4, not stripped # readelf -SW offwaketime_kern.o | grep PROGBITS [ 2] .text PROGBITS 0000000000000000 000040 000000 00 AX 0 0 4 [ 3] kprobe/try_to_wake_up PROGBITS 0000000000000000 000040 0000d8 00 AX 0 0 8 [ 5] tracepoint/sched/sched_switch PROGBITS 0000000000000000 000118 000318 00 AX 0 0 8 [ 7] maps PROGBITS 0000000000000000 000430 000050 00 WA 0 0 4 [ 8] license PROGBITS 0000000000000000 000480 000004 00 WA 0 0 1 [ 9] version PROGBITS 0000000000000000 000484 000004 00 WA 0 0 4 # ./offwaketime | head -5 swapper/1;start_secondary;cpu_startup_entry;schedule_preempt_disabled;schedule;__schedule;-;---;; 106 CPU 0/KVM;entry_SYSCALL_64_fastpath;sys_ioctl;do_vfs_ioctl;kvm_vcpu_ioctl;kvm_arch_vcpu_ioctl_run;kvm_vcpu_block;schedule;__schedule;-;try_to_wake_up;swake_up_locked;swake_up;apic_timer_expired;apic_timer_fn;__hrtimer_run_queues;hrtimer_interrupt;local_apic_timer_interrupt;smp_apic_timer_interrupt;__irqentry_text_start;cpuidle_enter;call_cpuidle;cpu_startup_entry;start_secondary;;swapper/3 2 Compositor;entry_SYSCALL_64_fastpath;sys_futex;do_futex;futex_wait;futex_wait_queue_me;schedule;__schedule;-;try_to_wake_up;futex_requeue;do_futex;sys_futex;entry_SYSCALL_64_fastpath;;SoftwareVsyncTh 5 firefox;entry_SYSCALL_64_fastpath;sys_poll;do_sys_poll;poll_schedule_timeout;schedule_hrtimeout_range;schedule_hrtimeout_range_clock;schedule;__schedule;-;try_to_wake_up;pollwake;__wake_up_common;__wake_up_sync_key;pipe_write;__vfs_write;vfs_write;sys_write;entry_SYSCALL_64_fastpath;;Timer 13 JS Helper;entry_SYSCALL_64_fastpath;sys_futex;do_futex;futex_wait;futex_wait_queue_me;schedule;__schedule;-;try_to_wake_up;do_futex;sys_futex;entry_SYSCALL_64_fastpath;;firefox 2 # Signed-off-by: Joe Stringer <joe@ovn.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Wang Nan <wangnan0@huawei.com> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/20161214224342.12858-2-joe@ovn.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-12-08bpf: xdp: Add XDP example for head adjustmentMartin KaFai Lau1-0/+94
The XDP prog checks if the incoming packet matches any VIP:PORT combination in the BPF hashmap. If it is, it will encapsulate the packet with a IPv4/v6 header as instructed by the value of the BPF hashmap and then XDP_TX it out. The VIP:PORT -> IP-Encap-Info can be specified by the cmd args of the user prog. Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02samples/bpf: Update bpf loader for cgroup section namesDavid Ahern1-3/+11
Add support for section names starting with cgroup/skb and cgroup/sock. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-24samples/bpf: fix bpf loaderAlexei Starovoitov1-0/+4
llvm can emit relocations into sections other than program code (like debug info sections). Ignore them during parsing of elf file Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02samples/bpf: add perf_event+bpf exampleAlexei Starovoitov1-1/+6
The bpf program is called 50 times a second and does hashmap[kern&user_stackid]++ It's primary purpose to check that key bpf helpers like map lookup, update, get_stackid, trace_printk and ctx access are all working. It checks: - PERF_COUNT_HW_CPU_CYCLES on all cpus - PERF_COUNT_HW_CPU_CYCLES for current process and inherited perf_events to children - PERF_COUNT_SW_CPU_CLOCK on all cpus - PERF_COUNT_SW_CPU_CLOCK for current process Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-19Add sample for adding simple drop program to linkBrenden Blanco1-0/+8
Add a sample program that only drops packets at the BPF_PROG_TYPE_XDP_RX hook of a link. With the drop-only program, observed single core rate is ~20Mpps. Other tests were run, for instance without the dropcnt increment or without reading from the packet header, the packet rate was mostly unchanged. $ perf record -a samples/bpf/xdp1 $(</sys/class/net/eth0/ifindex) proto 17: 20403027 drops/s ./pktgen_sample03_burst_single_flow.sh -i $DEV -d $IP -m $MAC -t 4 Running... ctrl^C to stop Device: eth4@0 Result: OK: 11791017(c11788327+d2689) usec, 59622913 (60byte,0frags) 5056638pps 2427Mb/sec (2427186240bps) errors: 0 Device: eth4@1 Result: OK: 11791012(c11787906+d3106) usec, 60526944 (60byte,0frags) 5133311pps 2463Mb/sec (2463989280bps) errors: 0 Device: eth4@2 Result: OK: 11791019(c11788249+d2769) usec, 59868091 (60byte,0frags) 5077431pps 2437Mb/sec (2437166880bps) errors: 0 Device: eth4@3 Result: OK: 11795039(c11792403+d2636) usec, 59483181 (60byte,0frags) 5043067pps 2420Mb/sec (2420672160bps) errors: 0 perf report --no-children: 26.05% ksoftirqd/0 [mlx4_en] [k] mlx4_en_process_rx_cq 17.84% ksoftirqd/0 [mlx4_en] [k] mlx4_en_alloc_frags 5.52% ksoftirqd/0 [mlx4_en] [k] mlx4_en_free_frag 4.90% swapper [kernel.vmlinux] [k] poll_idle 4.14% ksoftirqd/0 [kernel.vmlinux] [k] get_page_from_freelist 2.78% ksoftirqd/0 [kernel.vmlinux] [k] __free_pages_ok 2.57% ksoftirqd/0 [kernel.vmlinux] [k] bpf_map_lookup_elem 2.51% swapper [mlx4_en] [k] mlx4_en_process_rx_cq 1.94% ksoftirqd/0 [kernel.vmlinux] [k] percpu_array_map_lookup_elem 1.45% swapper [mlx4_en] [k] mlx4_en_alloc_frags 1.35% ksoftirqd/0 [kernel.vmlinux] [k] free_one_page 1.33% swapper [kernel.vmlinux] [k] intel_idle 1.04% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c5c5 0.96% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c58d 0.93% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c6ee 0.92% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c6b9 0.89% ksoftirqd/0 [kernel.vmlinux] [k] __alloc_pages_nodemask 0.83% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c686 0.83% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c5d5 0.78% ksoftirqd/0 [mlx4_en] [k] mlx4_alloc_pages.isra.23 0.77% ksoftirqd/0 [mlx4_en] [k] 0x000000000001c5b4 0.77% ksoftirqd/0 [kernel.vmlinux] [k] net_rx_action machine specs: receiver - Intel E5-1630 v3 @ 3.70GHz sender - Intel E5645 @ 2.40GHz Mellanox ConnectX-3 @40G Signed-off-by: Brenden Blanco <bblanco@plumgrid.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07samples/bpf: add tracepoint support to bpf loaderAlexei Starovoitov1-5/+21
Recognize "tracepoint/" section name prefix and attach the program to that tracepoint. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: add map_flags to bpf loaderAlexei Starovoitov1-1/+2
note old loader is compatible with new kernel. map_flags are optional Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: move ksym_search() into libraryAlexei Starovoitov1-0/+62
move ksym search from offwaketime into library to be reused in other tests Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08samples/bpf: make map creation more verboseAlexei Starovoitov1-1/+4
map creation is typically the first one to fail when rlimits are too low, not enough memory, etc Make this failure scenario more verbose Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-21samples/bpf: bpf_tail_call example for tracingAlexei Starovoitov1-12/+45
kprobe example that demonstrates how future seccomp programs may look like. It attaches to seccomp_phase1() function and tail-calls other BPF programs depending on syscall number. Existing optimized classic BPF seccomp programs generated by Chrome look like: if (sd.nr < 121) { if (sd.nr < 57) { if (sd.nr < 22) { if (sd.nr < 7) { if (sd.nr < 4) { if (sd.nr < 1) { check sys_read } else { if (sd.nr < 3) { check sys_write and sys_open } else { check sys_close } } } else { } else { } else { } else { } else { } the future seccomp using native eBPF may look like: bpf_tail_call(&sd, &syscall_jmp_table, sd.nr); which is simpler, faster and leaves more room for per-syscall checks. Usage: $ sudo ./tracex5 <...>-366 [001] d... 4.870033: : read(fd=1, buf=00007f6d5bebf000, size=771) <...>-369 [003] d... 4.870066: : mmap <...>-369 [003] d... 4.870077: : syscall=110 (one of get/set uid/pid/gid) <...>-369 [003] d... 4.870089: : syscall=107 (one of get/set uid/pid/gid) sh-369 [000] d... 4.891740: : read(fd=0, buf=00000000023d1000, size=512) sh-369 [000] d... 4.891747: : write(fd=1, buf=00000000023d3000, size=512) sh-369 [000] d... 4.891747: : read(fd=1, buf=00000000023d3000, size=512) Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-02samples/bpf: Add simple non-portable kprobe filter exampleAlexei Starovoitov1-8/+117
tracex1_kern.c - C program compiled into BPF. It attaches to kprobe:netif_receive_skb() When skb->dev->name == "lo", it prints sample debug message into trace_pipe via bpf_trace_printk() helper function. tracex1_user.c - corresponding user space component that: - loads BPF program via bpf() syscall - opens kprobes:netif_receive_skb event via perf_event_open() syscall - attaches the program to event via ioctl(event_fd, PERF_EVENT_IOC_SET_BPF, prog_fd); - prints from trace_pipe Note, this BPF program is non-portable. It must be recompiled with current kernel headers. kprobe is not a stable ABI and BPF+kprobe scripts may no longer be meaningful when kernel internals change. No matter in what way the kernel changes, neither the kprobe, nor the BPF program can ever crash or corrupt the kernel, assuming the kprobes, perf and BPF subsystem has no bugs. The verifier will detect that the program is using bpf_trace_printk() and the kernel will print 'this is a DEBUG kernel' warning banner, which means that bpf_trace_printk() should be used for debugging of the BPF program only. Usage: $ sudo tracex1 ping-19826 [000] d.s2 63103.382648: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63103.382684: : skb ffff880466b1d300 len 84 ping-19826 [000] d.s2 63104.382533: : skb ffff880466b1ca00 len 84 ping-19826 [000] d.s2 63104.382594: : skb ffff880466b1d300 len 84 Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David S. Miller <davem@davemloft.net> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/1427312966-8434-7-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-12-05samples: bpf: elf_bpf file loaderAlexei Starovoitov1-0/+203
simple .o parser and loader using BPF syscall. .o is a standard ELF generated by LLVM backend It parses elf file compiled by llvm .c->.o - parses 'maps' section and creates maps via BPF syscall - parses 'license' section and passes it to syscall - parses elf relocations for BPF maps and adjusts BPF_LD_IMM64 insns by storing map_fd into insn->imm and marking such insns as BPF_PSEUDO_MAP_FD - loads eBPF programs via BPF syscall One ELF file can contain multiple BPF programs. int load_bpf_file(char *path); populates prog_fd[] and map_fd[] with FDs received from bpf syscall bpf_helpers.h - helper functions available to eBPF programs written in C Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>