bpf: change x86 JITed program stack layout

Browse source

in order to JIT programs with different stack sizes we need to
make epilogue and exception path to be stack size independent,
hence move auxiliary stack space from the bottom of the stack
to the top of the stack.
Nice side effect is that JITed function prologue becomes shorter
due to imm8 offset encoding vs imm32.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

...

This commit is contained in:

Alexei Starovoitov 2017-05-30 13:31:34 -07:00 • committed by David S. Miller

parent b870aa901f

commit 177366bf7c

2 changed files with 40 additions and 38 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

20

arch/x86/net/bpf_jit.S

View file

56

arch/x86/net/bpf_jit_comp.c

View file