Re: linux-next: build failure after merge of the tip tree

Hi all,

After merging the tip tree, today's linux-next build (x86_64 allmodconfig)
failed like this:

arch/x86/net/bpf_jit_comp.c: In function 'arch_prepare_bpf_trampoline':
arch/x86/net/bpf_jit_comp.c:2015:16: error: 'ideal_nops' undeclared (first use in this function)
 2015 |   memcpy(prog, ideal_nops[NOP_ATOMIC5], X86_PATCH_SIZE);
      |                ^~~~~~~~~~
arch/x86/net/bpf_jit_comp.c:2015:16: note: each undeclared identifier is reported only once for each function it appears in
arch/x86/net/bpf_jit_comp.c:2015:27: error: 'NOP_ATOMIC5' undeclared (first use in this function); did you mean 'GFP_ATOMIC'?
 2015 |   memcpy(prog, ideal_nops[NOP_ATOMIC5], X86_PATCH_SIZE);
      |                           ^~~~~~~~~~~
      |                           GFP_ATOMIC

Caused by commit

  a89dfde3dc3c ("x86: Remove dynamic NOP selection")

interacting with commit

  b90829704780 ("bpf: Use NOP_ATOMIC5 instead of emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIG")

from the net tree.

I have applied the following merge fix patch.

From: Stephen Rothwell <redacted>
Date: Mon, 22 Mar 2021 14:30:37 +1100
Subject: [PATCH] x86: fix up for "bpf: Use NOP_ATOMIC5 instead of
 emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIG"

Signed-off-by: Stephen Rothwell <redacted>
---
 arch/x86/net/bpf_jit_comp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index db50ab14df67..e2b5da5d441d 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c

@@ -2012,7 +2012,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 		/* remember return value in a stack for bpf prog to access */
 		emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
 		im->ip_after_call = prog;
-		memcpy(prog, ideal_nops[NOP_ATOMIC5], X86_PATCH_SIZE);
+		memcpy(prog, x86_nops[5], X86_PATCH_SIZE);
 		prog += X86_PATCH_SIZE;
 	}
 

--