From 266a0a790fb545fa1802a899ac44f61b1d6335a7 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sat, 16 Apr 2016 22:29:33 +0200 Subject: [PATCH] bpf: avoid warning for wrong pointer cast Two new functions in bpf contain a cast from a 'u64' to a pointer. This works on 64-bit architectures but causes a warning on all 32-bit architectures: kernel/trace/bpf_trace.c: In function 'bpf_perf_event_output_tp': kernel/trace/bpf_trace.c:350:13: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] u64 ctx = *(long *)r1; This changes the cast to first convert the u64 argument into a uintptr_t, which is guaranteed to be the same size as a pointer. Signed-off-by: Arnd Bergmann Fixes: 9940d67c93b5 ("bpf: support bpf_get_stackid() and bpf_perf_event_output() in tracepoint programs") Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- kernel/trace/bpf_trace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 685587885374..f389629dade7 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -351,7 +351,7 @@ static u64 bpf_perf_event_output_tp(u64 r1, u64 r2, u64 index, u64 r4, u64 size) * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it * from there and call the same bpf_perf_event_output() helper */ - u64 ctx = *(long *)r1; + u64 ctx = *(long *)(uintptr_t)r1; return bpf_perf_event_output(ctx, r2, index, r4, size); } @@ -369,7 +369,7 @@ static const struct bpf_func_proto bpf_perf_event_output_proto_tp = { static u64 bpf_get_stackid_tp(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) { - u64 ctx = *(long *)r1; + u64 ctx = *(long *)(uintptr_t)r1; return bpf_get_stackid(ctx, r2, r3, r4, r5); } -- 2.45.2