Alexei Starovoitov wrote: > From: Yonghong Song <[email protected]> > > 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 <[email protected]> > Signed-off-by: Alexei Starovoitov <[email protected]> > Acked-by: Andrii Nakryiko <[email protected]> > --- > kernel/bpf/verifier.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-)
LGTM and will be useful. Acked-by: John Fastabend <[email protected]>
