On Tue, Oct 6, 2020 at 1:10 PM Alexei Starovoitov <alexei.starovoi...@gmail.com> wrote: > > From: Yonghong Song <y...@fb.com> > > Under register pressure the llvm may spill registers with bounds into the > stack. > The verifier has to track them through spill/fill otherwise many kinds of > bound > errors will be seen. The spill/fill of induction variables was already > happening. This patch extends this logic from tracking spill/fill of a > constant > into any bounded register. There is no need to track spill/fill of unbounded, > since no new information will be retrieved from the stack during register > fill. > > Though extra stack difference could cause state pruning to be less effective, > no > adverse affects were seen from this patch on selftests and on cilium programs. > > Signed-off-by: Yonghong Song <y...@fb.com> > Signed-off-by: Alexei Starovoitov <a...@kernel.org> > ---
Acked-by: Andrii Nakryiko <and...@kernel.org> > kernel/bpf/verifier.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > [...]