1. 11 Jun, 2018 2 commits
  2. 08 Jun, 2018 8 commits
  3. 06 Jun, 2018 5 commits
  4. 05 Jun, 2018 4 commits
  5. 03 Jun, 2018 1 commit
  6. 02 Jun, 2018 5 commits
    • Yonghong Song's avatar
      skip probe rewriter for bpf_probe_read() · 20fb64cd
      Yonghong Song authored
      bpf_probe_read() is often used to access pointees in bpf programs.
      Recent rewriter has become smarter so a lot of bpf_probe_read()
      can be replaced with simple pointer/member access.
      
      In certain cases, bpf_probe_read() is still preferred though.
      For example, kernel net/tcp.h defined TCP_SKB_CB as below
        #define TCP_SKB_CB(__skb)	((struct tcp_skb_cb *)&((__skb)->cb[0]))
      User can use below to access tcp_gso_size of a skb data structure.
        TCP_SKB_CB(skb)->tcp_gso_size
      The rewriter will fail as it attempts to rewrite (__skb)->cb[0].
      
      Instead of chasing down to prevent exactly the above pattern,
      this patch detects function bpf_probe_read() in ProbeVisitor and
      will skip it so bpf_probe_read()'s third parameter is a AddrOf.
      This can also help other cases where rewriter is not
      capable and user used bpf_probe_read() as the workaround.
      
      Also fixed tcptop.py to use direct assignment instead of
      bpf_probe_read. Otherwise, rewriter will actually rewrite
      src address reference inside the bpf_probe_read().
      Signed-off-by: default avatarYonghong Song <yhs@fb.com>
      20fb64cd
    • 4ast's avatar
      Merge pull request #1795 from iovisor/yhs_dev2 · db093366
      4ast authored
      Add "-D __BPF_TRACING__" to frontend compilation flags
      db093366
    • Yonghong Song's avatar
      Add "-D __BPF_TRACING__" to frontend compilation flags · 7c4311f6
      Yonghong Song authored
      In 4.17 kernel, x86 build requires compiler asm-goto support. clang
      does not support asm-goto and bpf program compilation started to break.
      The following kernel commit
      
        commit b1ae32dbab50ed19cfc16d225b0fb0114fb13025
        Author: Alexei Starovoitov <ast@kernel.org>
        Date:   Sun May 13 12:32:22 2018 -0700
      
            x86/cpufeature: Guard asm_volatile_goto usage for BPF compilation
      
            Workaround for the sake of BPF compilation which utilizes kernel
            headers, but clang does not support ASM GOTO and fails the build.
      
      workarounded the issue by permitting native clang compilation.
      A warning message, however, is issued:
      
        ./arch/x86/include/asm/cpufeature.h:150:2: warning: "Compiler lacks ASM_GOTO support.
              Add -D __BPF_TRACING__ to your compiler arguments" [-W#warnings]
        #warning "Compiler lacks ASM_GOTO support. Add -D __BPF_TRACING__ to your compil...
         ^
        1 warning generated.
      
      This patch added "-D __BPF_TRACING__" to clang frontend compilation to
      suppress the warning.
      Signed-off-by: default avatarYonghong Song <yhs@fb.com>
      7c4311f6
    • yonghong-song's avatar
      Merge pull request #1792 from pchaigno/refactor-ext-ptr-assignments · d8bb097d
      yonghong-song authored
      Refactor external pointer assignments
      d8bb097d
    • yonghong-song's avatar
      Merge pull request #1793 from qmonnet/kernelfeatures · c817cfd6
      yonghong-song authored
      sync BPF compat headers with latest bpf-next, update BPF features list
      c817cfd6
  7. 01 Jun, 2018 4 commits
  8. 31 May, 2018 1 commit
  9. 30 May, 2018 6 commits
  10. 29 May, 2018 4 commits