Re: [PATCH bpf] bpf, x64: fix stack layout of JITed bpf code

From: Alexei Starovoitov
Date: Sat Jun 15 2019 - 17:51:08 EST


On Fri, Jun 14, 2019 at 4:10 PM Alexei Starovoitov <ast@xxxxxxxxxx> wrote:
>
> Since commit 177366bf7ceb the %rbp stopped pointing to %rbp of the
> previous stack frame. That broke frame pointer based stack unwinding.
> This commit is a partial revert of it.
> Note that the location of tail_call_cnt is fixed, since the verifier
> enforces MAX_BPF_STACK stack size for programs with tail calls.
>
> Fixes: 177366bf7ceb ("bpf: change x86 JITed program stack layout")
> Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>

Applied to bpf tree.