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2019-11-18s390/bpf: Remove JITed image size limitationsIlya Leoshkevich
Now that jump and long displacement ranges are no longer a problem, remove the limit on JITed image size. In practice it's still limited by 2G, but with verifier allowing "only" 1M instructions, it's not an issue. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191118180340.68373-7-iii@linux.ibm.com
2019-11-18s390/bpf: Use lg(f)rl when long displacement cannot be usedIlya Leoshkevich
If literal pool grows past 524287 mark, it's no longer possible to use long displacement to reference literal pool entries. In JIT setting maintaining multiple literal pool registers is next to impossible, since we operate on one instruction at a time. Therefore, fall back to loading literal pool entry using PC-relative addressing, and then using a register-register form of the following machine instruction. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191118180340.68373-6-iii@linux.ibm.com
2019-11-18s390/bpf: Use lgrl instead of lg where possibleIlya Leoshkevich
lg and lgrl have the same performance characteristics, but the former requires a base register and is subject to long displacement range limits, while the latter does not. Therefore, lgrl is totally superior to lg and should be used instead whenever possible. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191118180340.68373-5-iii@linux.ibm.com
2019-11-18s390/bpf: Load literal pool register using larlIlya Leoshkevich
Currently literal pool register is loaded using basr, which makes it point not to the beginning of the literal pool, but rather to the next instruction. In case JITed code is larger than 512k, this renders literal pool register absolutely useless due to long displacement range restrictions. The solution is to use larl to make literal pool register point to the very beginning of the literal pool. This makes it always possible to address 512k worth of literal pool entries using long displacement. However, for short programs, in which the entire literal pool is covered by basr-generated base, it is still beneficial to use basr, since it is 4 bytes shorter than larl. Detect situations when basr-generated base does not cover the entire literal pool, and in such cases use larl instead. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191118180340.68373-4-iii@linux.ibm.com
2019-11-18s390/bpf: Align literal pool entriesIlya Leoshkevich
When literal pool size exceeds 512k, it's no longer possible to reference all the entries in it using a single base register and long displacement. Therefore, PC-relative lgfrl and lgrl instructions need to be used. Unfortunately, they require their arguments to be aligned to 4- and 8-byte boundaries respectively. This generates certain overhead due to necessary padding bytes. Grouping 4- and 8-byte entries together reduces the maximum overhead to 6 bytes (2 for aligning 4-byte entries and 4 for aligning 8-byte entries). While in theory it is possible to detect whether or not alignment is needed by comparing the literal pool size with 512k, in practice this leads to having two ways of emitting constants, making the code more complicated. Prefer code simplicity over trivial size saving, and always group and align literal pool entries. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191118180340.68373-3-iii@linux.ibm.com
2019-11-18s390/bpf: Use relative long branchesIlya Leoshkevich
Currently maximum JITed code size is limited to 64k, because JIT can emit only relative short branches, whose range is limited by 64k in both directions. Teach JIT to use relative long branches. There are no compare+branch relative long instructions, so using relative long branches consumes more space due to having to having to emit an explicit comparison instruction. Therefore do this only when relative short branch is not enough. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191118180340.68373-2-iii@linux.ibm.com
2019-11-15s390/bpf: Make sure JIT passes do not increase code sizeIlya Leoshkevich
The upcoming s390 branch length extension patches rely on "passes do not increase code size" property in order to consistently choose between short and long branches. Currently this property does not hold between the first and the second passes for register save/restore sequences, as well as various code fragments that depend on SEEN_* flags. Generate the code during the first pass conservatively: assume register save/restore sequences have the maximum possible length, and that all SEEN_* flags are set. Also refuse to JIT if this happens anyway (e.g. due to a bug), as this might lead to verifier bypass once long branches are introduced. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191114151820.53222-1-iii@linux.ibm.com
2019-11-07s390/bpf: Remove unused SEEN_RET0, SEEN_REG_AX and ret0_ipIlya Leoshkevich
We don't need them since commit e1cf4befa297 ("bpf, s390x: remove ld_abs/ld_ind") and commit a3212b8f15d8 ("bpf, s390x: remove obsolete exception handling from div/mod"). Also, use BIT(n) instead of 1 << n, because checkpatch says so. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191107114033.90505-1-iii@linux.ibm.com
2019-11-07s390/bpf: Wrap JIT macro parameter usages in parenthesesIlya Leoshkevich
This change does not alter JIT behavior; it only makes it possible to safely invoke JIT macros with complex arguments in the future. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191107113211.90105-1-iii@linux.ibm.com
2019-11-07s390/bpf: Use kvcalloc for addrs arrayIlya Leoshkevich
A BPF program may consist of 1m instructions, which means JIT instruction-address mapping can be as large as 4m. s390 has FORCE_MAX_ZONEORDER=9 (for memory hotplug reasons), which means maximum kmalloc size is 1m. This makes it impossible to JIT programs with more than 256k instructions. Fix by using kvcalloc, which falls back to vmalloc for larger allocations. An alternative would be to use a radix tree, but that is not supported by bpf_prog_fill_jited_linfo. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191107141838.92202-1-iii@linux.ibm.com
2019-09-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Add the ability to use unaligned chunks in the AF_XDP umem. By relaxing where the chunks can be placed, it allows to use an arbitrary buffer size and place whenever there is a free address in the umem. Helps more seamless DPDK AF_XDP driver integration. Support for i40e, ixgbe and mlx5e, from Kevin and Maxim. 2) Addition of a wakeup flag for AF_XDP tx and fill rings so the application can wake up the kernel for rx/tx processing which avoids busy-spinning of the latter, useful when app and driver is located on the same core. Support for i40e, ixgbe and mlx5e, from Magnus and Maxim. 3) bpftool fixes for printf()-like functions so compiler can actually enforce checks, bpftool build system improvements for custom output directories, and addition of 'bpftool map freeze' command, from Quentin. 4) Support attaching/detaching XDP programs from 'bpftool net' command, from Daniel. 5) Automatic xskmap cleanup when AF_XDP socket is released, and several barrier/{read,write}_once fixes in AF_XDP code, from Björn. 6) Relicense of bpf_helpers.h/bpf_endian.h for future libbpf inclusion as well as libbpf versioning improvements, from Andrii. 7) Several new BPF kselftests for verifier precision tracking, from Alexei. 8) Several BPF kselftest fixes wrt endianess to run on s390x, from Ilya. 9) And more BPF kselftest improvements all over the place, from Stanislav. 10) Add simple BPF map op cache for nfp driver to batch dumps, from Jakub. 11) AF_XDP socket umem mapping improvements for 32bit archs, from Ivan. 12) Add BPF-to-BPF call and BTF line info support for s390x JIT, from Yauheni. 13) Small optimization in arm64 JIT to spare 1 insns for BPF_MOD, from Jerin. 14) Fix an error check in bpf_tcp_gen_syncookie() helper, from Petar. 15) Various minor fixes and cleanups, from Nathan, Masahiro, Masanari, Peter, Wei, Yue. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-03bpf: s390: add JIT support for bpf line infoYauheni Kaliuta
This adds support for generating bpf line info for JITed programs like commit 6f20c71d8505 ("bpf: powerpc64: add JIT support for bpf line info") does for powerpc, but it should pass the array starting from 1. This fixes test_btf. Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-31bpf: s390: add JIT support for multi-function programsYauheni Kaliuta
This adds support for bpf-to-bpf function calls in the s390 JIT compiler. The JIT compiler converts the bpf call instructions to native branch instructions. After a round of the usual passes, the start addresses of the JITed images for the callee functions are known. Finally, to fixup the branch target addresses, we need to perform an extra pass. Because of the address range in which JITed images are allocated on s390, the offsets of the start addresses of these images from __bpf_call_base are as large as 64 bits. So, for a function call, the imm field of the instruction cannot be used to determine the callee's address. Use bpf_jit_get_func_addr() helper instead. The patch borrows a lot from: commit 8c11ea5ce13d ("bpf, arm64: fix getting subprog addr from aux for calls") commit e2c95a61656d ("bpf, ppc64: generalize fetching subprog into bpf_jit_get_func_addr") commit 8484ce8306f9 ("bpf: powerpc64: add JIT support for multi-function programs") (including the commit message). test_verifier (5.3-rc6 with CONFIG_BPF_JIT_ALWAYS_ON=y): without patch: Summary: 1501 PASSED, 0 SKIPPED, 47 FAILED with patch: Summary: 1540 PASSED, 0 SKIPPED, 8 FAILED Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-13s390/bpf: use 32-bit index for tail callsIlya Leoshkevich
"p runtime/jit: pass > 32bit index to tail_call" fails when bpf_jit_enable=1, because the tail call is not executed. This in turn is because the generated code assumes index is 64-bit, while it must be 32-bit, and as a result prog array bounds check fails, while it should pass. Even if bounds check would have passed, the code that follows uses 64-bit index to compute prog array offset. Fix by using clrj instead of clgrj for comparing index with array size, and also by using llgfr for truncating index to 32 bits before using it to compute prog array offset. Fixes: 6651ee070b31 ("s390/bpf: implement bpf_tail_call() helper") Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com> Acked-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-12s390/bpf: fix lcgr instruction encodingIlya Leoshkevich
"masking, test in bounds 3" fails on s390, because BPF_ALU64_IMM(BPF_NEG, BPF_REG_2, 0) ignores the top 32 bits of BPF_REG_2. The reason is that JIT emits lcgfr instead of lcgr. The associated comment indicates that the code was intended to emit lcgr in the first place, it's just that the wrong opcode was used. Fix by using the correct opcode. Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-05-24s390: bpf: eliminate zero extension code-genJiong Wang
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-11s390: Convert IS_ENABLED uses to __is_definedJoe Perches
IS_ENABLED should be reserved for CONFIG_<FOO> uses so convert the uses of IS_ENABLED with a #define to __is_defined. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-02-21s390/net: convert pnetids to asciiHans Wippel
Pnetids are retrieved from the underlying hardware as EBCDIC. This patch converts pnetids to ASCII. Signed-off-by: Hans Wippel <hwippel@linux.ibm.com> Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-07s390/net: move pnet constantsUrsula Braun
There is no need to define these PNETID related constants in the pnet.h file, since they are just used locally within pnet.c. Just code cleanup, no functional change. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-04s390: bpf: fix JMP32 code-genHeiko Carstens
Commit 626a5f66da0d19 ("s390: bpf: implement jitting of JMP32") added JMP32 code-gen support for s390. However it triggers the warning below due to some unusual gotos in the original s390 bpf jit code. Add a couple of additional "is_jmp32" initializations to fix this. Also fix the wrong opcode for the "llilf" instruction that was introduced with the same commit. arch/s390/net/bpf_jit_comp.c: In function 'bpf_jit_insn': arch/s390/net/bpf_jit_comp.c:248:55: warning: 'is_jmp32' may be used uninitialized in this function [-Wmaybe-uninitialized] _EMIT6(op1 | reg(b1, b2) << 16 | (rel & 0xffff), op2 | mask); \ ^ arch/s390/net/bpf_jit_comp.c:1211:8: note: 'is_jmp32' was declared here bool is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32; Fixes: 626a5f66da0d19 ("s390: bpf: implement jitting of JMP32") Cc: Jiong Wang <jiong.wang@netronome.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Jiong Wang <jiong.wang@netronome.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-26s390: bpf: implement jitting of JMP32Jiong Wang
This patch implements code-gen for new JMP32 instructions on s390. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-12-07s390: bpf: implement jitting of BPF_ALU | BPF_ARSH | BPF_*Jiong Wang
This patch implements code-gen for BPF_ALU | BPF_ARSH | BPF_*. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-08-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: "Since Martin is on vacation you get the s390 pull request from me: - Host large page support for KVM guests. As the patches have large impact on arch/s390/mm/ this series goes out via both the KVM and the s390 tree. - Add an option for no compression to the "Kernel compression mode" menu, this will come in handy with the rework of the early boot code. - A large rework of the early boot code that will make life easier for KASAN and KASLR. With the rework the bootable uncompressed image is not generated anymore, only the bzImage is available. For debuggung purposes the new "no compression" option is used. - Re-enable the gcc plugins as the issue with the latent entropy plugin is solved with the early boot code rework. - More spectre relates changes: + Detect the etoken facility and remove expolines automatically. + Add expolines to a few more indirect branches. - A rewrite of the common I/O layer trace points to make them consumable by 'perf stat'. - Add support for format-3 PCI function measurement blocks. - Changes for the zcrypt driver: + Add attributes to indicate the load of cards and queues. + Restructure some code for the upcoming AP device support in KVM. - Build flags improvements in various Makefiles. - A few fixes for the kdump support. - A couple of patches for gcc 8 compile warning cleanup. - Cleanup s390 specific proc handlers. - Add s390 support to the restartable sequence self tests. - Some PTR_RET vs PTR_ERR_OR_ZERO cleanup. - Lots of bug fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (107 commits) s390/dasd: fix hanging offline processing due to canceled worker s390/dasd: fix panic for failed online processing s390/mm: fix addressing exception after suspend/resume rseq/selftests: add s390 support s390: fix br_r1_trampoline for machines without exrl s390/lib: use expoline for all bcr instructions s390/numa: move initial setup of node_to_cpumask_map s390/kdump: Fix elfcorehdr size calculation s390/cpum_sf: save TOD clock base in SDBs for time conversion KVM: s390: Add huge page enablement control s390/mm: Add huge page gmap linking support s390/mm: hugetlb pages within a gmap can not be freed KVM: s390: Add skey emulation fault handling s390/mm: Add huge pmd storage key handling s390/mm: Clear skeys for newly mapped huge guest pmds s390/mm: Clear huge page storage keys on enable_skey s390/mm: Add huge page dirty sync support s390/mm: Add gmap pmd invalidation and clearing s390/mm: Add gmap pmd notification bit setting s390/mm: Add gmap pmd linking ...
2018-08-07s390: fix br_r1_trampoline for machines without exrlMartin Schwidefsky
For machines without the exrl instruction the BFP jit generates code that uses an "br %r1" instruction located in the lowcore page. Unfortunately there is a cut & paste error that puts an additional "larl %r1,.+14" instruction in the code that clobbers the branch target address in %r1. Remove the larl instruction. Cc: <stable@vger.kernel.org> # v4.17+ Fixes: de5cb6eb51 ("s390: use expoline thunks in the BPF JIT") Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-29bpf, s390: fix potential memleak when later bpf_jit_prog failsDaniel Borkmann
If we would ever fail in the bpf_jit_prog() pass that writes the actual insns to the image after we got header via bpf_jit_binary_alloc() then we also need to make sure to free it through bpf_jit_binary_free() again when bailing out. Given we had prior bpf_jit_prog() passes to initially probe for clobbered registers, program size and to fill in addrs arrray for jump targets, this is more of a theoretical one, but at least make sure this doesn't break with future changes. Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW 8.37.2.0 ...
2018-05-30s390/net: add pnetid supportUrsula Braun
s390 hardware supports the definition of a so-call Physical NETwork IDentifier (short PNETID) per network device port. These PNETIDS can be used to identify network devices that are attached to the same physical network (broadcast domain). This patch provides the interface to extract the PNETID of a port of a device attached to the ccw-bus or pci-bus. Parts of this patch are based on an initial implementation by Thomas Richter. Signed-off-by: Ursula Braun <ubraun@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-05-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
S390 bpf_jit.S is removed in net-next and had changes in 'net', since that code isn't used any more take the removal. TLS data structures split the TX and RX components in 'net-next', put the new struct members from the bug fix in 'net' into the RX part. The 'net-next' tree had some reworking of how the ERSPAN code works in the GRE tunneling code, overlapping with a one-line headroom calculation fix in 'net'. Overlapping changes in __sock_map_ctx_update_elem(), keep the bits that read the prog members via READ_ONCE() into local variables before using them. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-07s390: use expoline thunks in the BPF JITMartin Schwidefsky
The BPF JIT need safe guarding against spectre v2 in the sk_load_xxx assembler stubs and the indirect branches generated by the JIT itself need to be converted to expolines. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-05-03bpf, s390x: remove ld_abs/ld_indDaniel Borkmann
Since LD_ABS/LD_IND instructions are now removed from the core and reimplemented through a combination of inlined BPF instructions and a slow-path helper, we can get rid of the complexity from s390x JIT. Tested on s390x instance on LinuxONE. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-26bpf, s390x: remove obsolete exception handling from div/modDaniel Borkmann
Since we've changed div/mod exception handling for src_reg in eBPF verifier itself, remove the leftovers from s390x JIT. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-19bpf: get rid of pure_initcall dependency to enable jitsDaniel Borkmann
Having a pure_initcall() callback just to permanently enable BPF JITs under CONFIG_BPF_JIT_ALWAYS_ON is unnecessary and could leave a small race window in future where JIT is still disabled on boot. Since we know about the setting at compilation time anyway, just initialize it properly there. Also consolidate all the individual bpf_jit_enable variables into a single one and move them under one location. Moreover, don't allow for setting unspecified garbage values on them. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Lots of overlapping changes. Also on the net-next side the XDP state management is handled more in the generic layers so undo the 'net' nfp fix which isn't applicable in net-next. Include a necessary change by Jakub Kicinski, with log message: ==================== cls_bpf no longer takes care of offload tracking. Make sure netdevsim performs necessary checks. This fixes a warning caused by TC trying to remove a filter it has not added. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2017-12-18 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Allow arbitrary function calls from one BPF function to another BPF function. As of today when writing BPF programs, __always_inline had to be used in the BPF C programs for all functions, unnecessarily causing LLVM to inflate code size. Handle this more naturally with support for BPF to BPF calls such that this __always_inline restriction can be overcome. As a result, it allows for better optimized code and finally enables to introduce core BPF libraries in the future that can be reused out of different projects. x86 and arm64 JIT support was added as well, from Alexei. 2) Add infrastructure for tagging functions as error injectable and allow for BPF to return arbitrary error values when BPF is attached via kprobes on those. This way of injecting errors generically eases testing and debugging without having to recompile or restart the kernel. Tags for opting-in for this facility are added with BPF_ALLOW_ERROR_INJECTION(), from Josef. 3) For BPF offload via nfp JIT, add support for bpf_xdp_adjust_head() helper call for XDP programs. First part of this work adds handling of BPF capabilities included in the firmware, and the later patches add support to the nfp verifier part and JIT as well as some small optimizations, from Jakub. 4) The bpftool now also gets support for basic cgroup BPF operations such as attaching, detaching and listing current BPF programs. As a requirement for the attach part, bpftool can now also load object files through 'bpftool prog load'. This reuses libbpf which we have in the kernel tree as well. bpftool-cgroup man page is added along with it, from Roman. 5) Back then commit e87c6bc3852b ("bpf: permit multiple bpf attachments for a single perf event") added support for attaching multiple BPF programs to a single perf event. Given they are configured through perf's ioctl() interface, the interface has been extended with a PERF_EVENT_IOC_QUERY_BPF command in this work in order to return an array of one or multiple BPF prog ids that are currently attached, from Yonghong. 6) Various minor fixes and cleanups to the bpftool's Makefile as well as a new 'uninstall' and 'doc-uninstall' target for removing bpftool itself or prior installed documentation related to it, from Quentin. 7) Add CONFIG_CGROUP_BPF=y to the BPF kernel selftest config file which is required for the test_dev_cgroup test case to run, from Naresh. 8) Fix reporting of XDP prog_flags for nfp driver, from Jakub. 9) Fix libbpf's exit code from the Makefile when libelf was not found in the system, also from Jakub. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-17bpf: fix net.core.bpf_jit_enable raceAlexei Starovoitov
global bpf_jit_enable variable is tested multiple times in JITs, blinding and verifier core. The malicious root can try to toggle it while loading the programs. This race condition was accounted for and there should be no issues, but it's safer to avoid this race condition. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-15bpf, s390x: do not reload skb pointers in non-skb contextDaniel Borkmann
The assumption of unconditionally reloading skb pointers on BPF helper calls where bpf_helper_changes_pkt_data() holds true is wrong. There can be different contexts where the BPF helper would enforce a reload such as in case of XDP. Here, we do have a struct xdp_buff instead of struct sk_buff as context, thus this will access garbage. JITs only ever need to deal with cached skb pointer reload when ld_abs/ind was seen, therefore guard the reload behind SEEN_SKB only. Tested on s390x. Fixes: 9db7f2b81880 ("s390/bpf: recache skb->data/hlen for skb_vlan_push/pop") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-05s390: add a few more SPDX identifiersMartin Schwidefsky
Add the correct SPDX license to a few more files under arch/s390 and drivers/s390 which have been missed to far. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: "Since Martin is on vacation you get the s390 pull request for the v4.15 merge window this time from me. Besides a lot of cleanups and bug fixes these are the most important changes: - a new regset for runtime instrumentation registers - hardware accelerated AES-GCM support for the aes_s390 module - support for the new CEX6S crypto cards - support for FORTIFY_SOURCE - addition of missing z13 and new z14 instructions to the in-kernel disassembler - generate opcode tables for the in-kernel disassembler out of a simple text file instead of having to manually maintain those tables - fast memset16, memset32 and memset64 implementations - removal of named saved segment support - hardware counter support for z14 - queued spinlocks and queued rwlocks implementations for s390 - use the stack_depth tracking feature for s390 BPF JIT - a new s390_sthyi system call which emulates the sthyi (store hypervisor information) instruction - removal of the old KVM virtio transport - an s390 specific CPU alternatives implementation which is used in the new spinlock code" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits) MAINTAINERS: add virtio-ccw.h to virtio/s390 section s390/noexec: execute kexec datamover without DAT s390: fix transactional execution control register handling s390/bpf: take advantage of stack_depth tracking s390: simplify transactional execution elf hwcap handling s390/zcrypt: Rework struct ap_qact_ap_info. s390/virtio: remove unused header file kvm_virtio.h s390: avoid undefined behaviour s390/disassembler: generate opcode tables from text file s390/disassembler: remove insn_to_mnemonic() s390/dasd: avoid calling do_gettimeofday() s390: vfio-ccw: Do not attempt to free no-op, test and tic cda. s390: remove named saved segment support s390/archrandom: Reconsider s390 arch random implementation s390/pci: do not require AIS facility s390/qdio: sanitize put_indicator s390/qdio: use atomic_cmpxchg s390/nmi: avoid using long-displacement facility s390: pass endianness info to sparse s390/decompressor: remove informational messages ...
2017-11-10s390/bpf: take advantage of stack_depth trackingMichael Holzheu
Make use of the "stack_depth" tracking feature introduced with commit 8726679a0fa31 ("bpf: teach verifier to track stack depth") for the s390 JIT, so that stack usage can be reduced. Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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>
2017-08-09bpf, s390x: implement jiting of BPF_J{LT, LE, SLT, SLE}Daniel Borkmann
This work implements jiting of BPF_J{LT,LE,SLT,SLE} instructions with BPF_X/BPF_K variants for the s390x eBPF JIT. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-04bpf, s390: fix jit branch offset related to ldimm64Daniel Borkmann
While testing some other work that required JIT modifications, I run into test_bpf causing a hang when JIT enabled on s390. The problematic test case was the one from ddc665a4bb4b (bpf, arm64: fix jit branch offset related to ldimm64), and turns out that we do have a similar issue on s390 as well. In bpf_jit_prog() we update next instruction address after returning from bpf_jit_insn() with an insn_count. bpf_jit_insn() returns either -1 in case of error (e.g. unsupported insn), 1 or 2. The latter is only the case for ldimm64 due to spanning 2 insns, however, next address is only set to i + 1 not taking actual insn_count into account, thus fix is to use insn_count instead of 1. bpf_jit_enable in mode 2 provides also disasm on s390: Before fix: 000003ff800349b6: a7f40003 brc 15,3ff800349bc ; target 000003ff800349ba: 0000 unknown 000003ff800349bc: e3b0f0700024 stg %r11,112(%r15) 000003ff800349c2: e3e0f0880024 stg %r14,136(%r15) 000003ff800349c8: 0db0 basr %r11,%r0 000003ff800349ca: c0ef00000000 llilf %r14,0 000003ff800349d0: e320b0360004 lg %r2,54(%r11) 000003ff800349d6: e330b03e0004 lg %r3,62(%r11) 000003ff800349dc: ec23ffeda065 clgrj %r2,%r3,10,3ff800349b6 ; jmp 000003ff800349e2: e3e0b0460004 lg %r14,70(%r11) 000003ff800349e8: e3e0b04e0004 lg %r14,78(%r11) 000003ff800349ee: b904002e lgr %r2,%r14 000003ff800349f2: e3b0f0700004 lg %r11,112(%r15) 000003ff800349f8: e3e0f0880004 lg %r14,136(%r15) 000003ff800349fe: 07fe bcr 15,%r14 After fix: 000003ff80ef3db4: a7f40003 brc 15,3ff80ef3dba 000003ff80ef3db8: 0000 unknown 000003ff80ef3dba: e3b0f0700024 stg %r11,112(%r15) 000003ff80ef3dc0: e3e0f0880024 stg %r14,136(%r15) 000003ff80ef3dc6: 0db0 basr %r11,%r0 000003ff80ef3dc8: c0ef00000000 llilf %r14,0 000003ff80ef3dce: e320b0360004 lg %r2,54(%r11) 000003ff80ef3dd4: e330b03e0004 lg %r3,62(%r11) 000003ff80ef3dda: ec230006a065 clgrj %r2,%r3,10,3ff80ef3de6 ; jmp 000003ff80ef3de0: e3e0b0460004 lg %r14,70(%r11) 000003ff80ef3de6: e3e0b04e0004 lg %r14,78(%r11) ; target 000003ff80ef3dec: b904002e lgr %r2,%r14 000003ff80ef3df0: e3b0f0700004 lg %r11,112(%r15) 000003ff80ef3df6: e3e0f0880004 lg %r14,136(%r15) 000003ff80ef3dfc: 07fe bcr 15,%r14 test_bpf.ko suite runs fine after the fix. Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-06bpf: Add jited_len to struct bpf_progMartin KaFai Lau
Add jited_len to struct bpf_prog. It will be useful for the struct bpf_prog_info which will be added in the later patch. 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>
2017-05-31bpf: free up BPF_JMP | BPF_CALL | BPF_X opcodeAlexei Starovoitov
free up BPF_JMP | BPF_CALL | BPF_X opcode to be used by actual indirect call by register and use kernel internal opcode to mark call instruction into bpf_tail_call() helper. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-08s390: use set_memory.h headerLaura Abbott
set_memory_* functions have moved to set_memory.h. Switch to this explicitly Link: http://lkml.kernel.org/r/1488920133-27229-5-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: - New entropy generation for the pseudo random number generator. - Early boot printk output via sclp to help debug crashes on boot. This needs to be enabled with a kernel parameter. - Add proper no-execute support with a bit in the page table entry. - Bug fixes and cleanups. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (65 commits) s390/syscall: fix single stepped system calls s390/zcrypt: make ap_bus explicitly non-modular s390/zcrypt: Removed unneeded debug feature directory creation. s390: add missing "do {} while (0)" loop constructs to multiline macros s390/mm: add cond_resched call to kernel page table dumper s390: get rid of MACHINE_HAS_PFMF and MACHINE_HAS_HPAGE s390/mm: make memory_block_size_bytes available for !MEMORY_HOTPLUG s390: replace ACCESS_ONCE with READ_ONCE s390: Audit and remove any remaining unnecessary uses of module.h s390: mm: Audit and remove any unnecessary uses of module.h s390: kernel: Audit and remove any unnecessary uses of module.h s390/kdump: Use "LINUX" ELF note name instead of "CORE" s390: add no-execute support s390: report new vector facilities s390: use correct input data address for setup_randomness s390/sclp: get rid of common response code handling s390/sclp: don't add new lines to each printed string s390/sclp: make early sclp code readable s390/sclp: disable early sclp code as soon as the base sclp driver is active s390/sclp: move early printk code to drivers ...
2017-02-21bpf: fix unlocking of jited image when module ronx not setDaniel Borkmann
Eric and Willem reported that they recently saw random crashes when JIT was in use and bisected this to 74451e66d516 ("bpf: make jited programs visible in traces"). Issue was that the consolidation part added bpf_jit_binary_unlock_ro() that would unlock previously made read-only memory back to read-write. However, DEBUG_SET_MODULE_RONX cannot be used for this to test for presence of set_memory_*() functions. We need to use ARCH_HAS_SET_MEMORY instead to fix this; also add the corresponding bpf_jit_binary_lock_ro() to filter.h. Fixes: 74451e66d516 ("bpf: make jited programs visible in traces") Reported-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Bisected-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-17bpf: make jited programs visible in tracesDaniel Borkmann
Long standing issue with JITed programs is that stack traces from function tracing check whether a given address is kernel code through {__,}kernel_text_address(), which checks for code in core kernel, modules and dynamically allocated ftrace trampolines. But what is still missing is BPF JITed programs (interpreted programs are not an issue as __bpf_prog_run() will be attributed to them), thus when a stack trace is triggered, the code walking the stack won't see any of the JITed ones. The same for address correlation done from user space via reading /proc/kallsyms. This is read by tools like perf, but the latter is also useful for permanent live tracing with eBPF itself in combination with stack maps when other eBPF types are part of the callchain. See offwaketime example on dumping stack from a map. This work tries to tackle that issue by making the addresses and symbols known to the kernel. The lookup from *kernel_text_address() is implemented through a latched RB tree that can be read under RCU in fast-path that is also shared for symbol/size/offset lookup for a specific given address in kallsyms. The slow-path iteration through all symbols in the seq file done via RCU list, which holds a tiny fraction of all exported ksyms, usually below 0.1 percent. Function symbols are exported as bpf_prog_<tag>, in order to aide debugging and attribution. This facility is currently enabled for root-only when bpf_jit_kallsyms is set to 1, and disabled if hardening is active in any mode. The rationale behind this is that still a lot of systems ship with world read permissions on kallsyms thus addresses should not get suddenly exposed for them. If that situation gets much better in future, we always have the option to change the default on this. Likewise, unprivileged programs are not allowed to add entries there either, but that is less of a concern as most such programs types relevant in this context are for root-only anyway. If enabled, call graphs and stack traces will then show a correct attribution; one example is illustrated below, where the trace is now visible in tooling such as perf script --kallsyms=/proc/kallsyms and friends. Before: 7fff8166889d bpf_clone_redirect+0x80007f0020ed (/lib/modules/4.9.0-rc8+/build/vmlinux) f5d80 __sendmsg_nocancel+0xffff006451f1a007 (/usr/lib64/libc-2.18.so) After: 7fff816688b7 bpf_clone_redirect+0x80007f002107 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fffa0575728 bpf_prog_33c45a467c9e061a+0x8000600020fb (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fffa07ef1fc cls_bpf_classify+0x8000600020dc (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff81678b68 tc_classify+0x80007f002078 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164d40b __netif_receive_skb_core+0x80007f0025fb (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164d718 __netif_receive_skb+0x80007f002018 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164e565 process_backlog+0x80007f002095 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164dc71 net_rx_action+0x80007f002231 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff81767461 __softirqentry_text_start+0x80007f0020d1 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff817658ac do_softirq_own_stack+0x80007f00201c (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff810a2c20 do_softirq+0x80007f002050 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff810a2cb5 __local_bh_enable_ip+0x80007f002085 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8168d452 ip_finish_output2+0x80007f002152 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8168ea3d ip_finish_output+0x80007f00217d (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8168f2af ip_output+0x80007f00203f (/lib/modules/4.9.0-rc8+/build/vmlinux) [...] 7fff81005854 do_syscall_64+0x80007f002054 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff817649eb return_from_SYSCALL_64+0x80007f002000 (/lib/modules/4.9.0-rc8+/build/vmlinux) f5d80 __sendmsg_nocancel+0xffff01c484812007 (/usr/lib64/libc-2.18.so) Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-17bpf: remove stubs for cBPF from arch codeDaniel Borkmann
Remove the dummy bpf_jit_compile() stubs for eBPF JITs and make that a single __weak function in the core that can be overridden similarly to the eBPF one. Also remove stale pr_err() mentions of bpf_jit_compile. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-16s390/bpf: remove redundant check for non-null imageDaniel Borkmann
After we already allocated the jit.prg_buf image via bpf_jit_binary_alloc() and filled it out with instructions, jit.prg_buf cannot be NULL anymore. Thus, remove the unnecessary check. Tested on s390x with test_bpf module. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>