From f23bc46c30ca5ef58b8549434899fcbac41b2cfc Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Thu, 15 Dec 2016 12:12:54 -0800 Subject: [PATCH] net: xdp: add invalid buffer warning This adds a warning for drivers to use when encountering an invalid buffer for XDP. For normal cases this should not happen but to catch this in virtual/qemu setups that I may not have expected from the emulation layer having a standard warning is useful. Signed-off-by: John Fastabend Signed-off-by: David S. Miller --- include/linux/filter.h | 1 + net/core/filter.c | 6 ++++++ 2 files changed, 7 insertions(+) diff --git a/include/linux/filter.h b/include/linux/filter.h index 6a1658308612..af8a1804cac6 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -602,6 +602,7 @@ bool bpf_helper_changes_pkt_data(void *func); struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, const struct bpf_insn *patch, u32 len); void bpf_warn_invalid_xdp_action(u32 act); +void bpf_warn_invalid_xdp_buffer(void); #ifdef CONFIG_BPF_JIT extern int bpf_jit_enable; diff --git a/net/core/filter.c b/net/core/filter.c index b1461708a977..7190bd648154 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2972,6 +2972,12 @@ void bpf_warn_invalid_xdp_action(u32 act) } EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action); +void bpf_warn_invalid_xdp_buffer(void) +{ + WARN_ONCE(1, "Illegal XDP buffer encountered, expect throughput degradation\n"); +} +EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_buffer); + static u32 sk_filter_convert_ctx_access(enum bpf_access_type type, int dst_reg, int src_reg, int ctx_off, struct bpf_insn *insn_buf, -- 2.20.1