From e1abf2cc8d5d80b41c4419368ec743ccadbb131e Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 2 Apr 2015 15:51:39 +0200 Subject: bpf: Fix the build on BPF_SYSCALL=y && !CONFIG_TRACING kernels, make it more configurable MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit So bpf_tracing.o depends on CONFIG_BPF_SYSCALL - but that's not its only dependency, it also depends on the tracing infrastructure and on kprobes, without which it will fail to build with: In file included from kernel/trace/bpf_trace.c:14:0: kernel/trace/trace.h: In function ‘trace_test_and_set_recursion’: kernel/trace/trace.h:491:28: error: ‘struct task_struct’ has no member named ‘trace_recursion’ unsigned int val = current->trace_recursion; [...] It took quite some time to trigger this build failure, because right now BPF_SYSCALL is very obscure, depends on CONFIG_EXPERT. So also make BPF_SYSCALL more configurable, not just under CONFIG_EXPERT. If BPF_SYSCALL, tracing and kprobes are enabled then enable the bpf_tracing gateway as well. We might want to make this an interactive option later on, although I'd not complicate it unnecessarily: enabling BPF_SYSCALL is enough of an indicator that the user wants BPF support. Cc: Alexei Starovoitov Cc: Andrew Morton Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Daniel Borkmann Cc: David S. Miller Cc: Jiri Olsa Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Peter Zijlstra Cc: Steven Rostedt Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- init/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'init') diff --git a/init/Kconfig b/init/Kconfig index f5dbc6d..2b4d055 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1513,7 +1513,7 @@ config EVENTFD # syscall, maps, verifier config BPF_SYSCALL - bool "Enable bpf() system call" if EXPERT + bool "Enable bpf() system call" select ANON_INODES select BPF default n -- cgit v1.1