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  • Hendrik Brueckner's avatar
    bpf: correct broken uapi for BPF_PROG_TYPE_PERF_EVENT program type · c895f6f7
    Hendrik Brueckner authored
    Commit 0515e599
    
     ("bpf: introduce BPF_PROG_TYPE_PERF_EVENT
    program type") introduced the bpf_perf_event_data structure which
    exports the pt_regs structure.  This is OK for multiple architectures
    but fail for s390 and arm64 which do not export pt_regs.  Programs
    using them, for example, the bpf selftest fail to compile on these
    architectures.
    
    For s390, exporting the pt_regs is not an option because s390 wants
    to allow changes to it.  For arm64, there is a user_pt_regs structure
    that covers parts of the pt_regs structure for use by user space.
    
    To solve the broken uapi for s390 and arm64, introduce an abstract
    type for pt_regs and add an asm/bpf_perf_event.h file that concretes
    the type.  An asm-generic header file covers the architectures that
    export pt_regs today.
    
    The arch-specific enablement for s390 and arm64 follows in separate
    commits.
    
    Reported-by: default avatarThomas Richter <tmricht@linux.vnet.ibm.com>
    Fixes: 0515e599
    
     ("bpf: introduce BPF_PROG_TYPE_PERF_EVENT program type")
    Signed-off-by: default avatarHendrik Brueckner <brueckner@linux.vnet.ibm.com>
    Reviewed-and-tested-by: default avatarThomas Richter <tmricht@linux.vnet.ibm.com>
    Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
    Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
    Cc: Jiri Olsa <jolsa@redhat.com>
    Cc: Namhyung Kim <namhyung@kernel.org>
    Cc: Arnd Bergmann <arnd@arndb.de>
    Cc: Daniel Borkmann <daniel@iogearbox.net>
    Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
    c895f6f7