6.6-stable review patch. If anyone has any objections, please let me know.
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From: Chenghao Duan duanchenghao@kylinos.cn
[ Upstream commit d0bf7cd5df18466d969bb60e8890b74cf96081ca ]
In the __arch_prepare_bpf_trampoline() function, retval_off is only meaningful when save_ret is true, so the current logic is correct. However, in the original logic, retval_off is only initialized under certain conditions; for example, in the fmod_ret logic, the compiler is not aware that the flags of the fmod_ret program (prog) have set BPF_TRAMP_F_CALL_ORIG, which results in an uninitialized symbol compilation warning.
So initialize retval_off unconditionally to fix it.
Signed-off-by: Chenghao Duan duanchenghao@kylinos.cn Reviewed-by: Pu Lehui pulehui@huawei.com Link: https://lore.kernel.org/r/20250922062244.822937-2-duanchenghao@kylinos.cn Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- arch/riscv/net/bpf_jit_comp64.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index 16eb4cd11cbd6..5426dc2697f94 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -855,10 +855,9 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, stack_size += 16;
save_ret = flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET); - if (save_ret) { + if (save_ret) stack_size += 16; /* Save both A5 (BPF R0) and A0 */ - retval_off = stack_size; - } + retval_off = stack_size;
stack_size += nregs * 8; args_off = stack_size;