[PATCH] powerpc32/bpf: return false from bpf_jit_supports_fsession() on ppc32
DORMANTno replies
From: Karl Mehltretter <hidden>
Date: 2026-10-03 18:42:58
Also in:
bpf, lkml
Subsystem:
bpf jit for powerpc (32-bit and 64-bit), bpf [general] (safe dynamic programs and tools), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Hari Bathini, Christophe Leroy, Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Madhavan Srinivasan, Linus Torvalds
bpf_jit_supports_fsession() returns bool. Commit 92258b5bf1ec
("powerpc32/bpf: Add fsession support") made it return -EOPNOTSUPP on
ppc32 until fsession is validated there. The negative value converts to
true, so the verifier does not reject fsession programs on ppc32. Such a
program loads, and only attaching it fails because
__arch_prepare_bpf_trampoline() returns -EOPNOTSUPP on ppc32.
Return false instead. The load then fails with "JIT does not support
fsession". Tested with a ppc32 kernel on QEMU g3beige.
Fixes: 92258b5bf1ec ("powerpc32/bpf: Add fsession support")
Reported-by: kernel test robot <redacted>
Reported-by: Dan Carpenter <redacted>
Closes: https://lore.kernel.org/r/202608010958.cYfBCQAC-lkp@intel.com/ (local)
Assisted-by: LLM
Signed-off-by: Karl Mehltretter <redacted>
---
arch/powerpc/net/bpf_jit_comp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 7a612688e7a2..64e70f3226b2 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c@@ -539,7 +539,7 @@ bool bpf_jit_supports_fsession(void) * for fsession and trampoline on ppc32. */ if (IS_ENABLED(CONFIG_PPC32)) - return -EOPNOTSUPP; + return false; return true; }
base-commit: e767a4ea70a3992c37ed604157d32f0dfbf9b1e3 -- 2.53.0