linux/arch/s390/net
Ilya Leoshkevich fcf3513139 s390/bpf: Make sure JIT passes do not increase code size
The upcoming s390 branch length extension patches rely on "passes do
not increase code size" property in order to consistently choose between
short and long branches. Currently this property does not hold between
the first and the second passes for register save/restore sequences, as
well as various code fragments that depend on SEEN_* flags.

Generate the code during the first pass conservatively: assume register
save/restore sequences have the maximum possible length, and that all
SEEN_* flags are set.

Also refuse to JIT if this happens anyway (e.g. due to a bug), as this
might lead to verifier bypass once long branches are introduced.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191114151820.53222-1-iii@linux.ibm.com
2019-11-15 22:25:54 +01:00
..
bpf_jit_comp.c s390/bpf: Make sure JIT passes do not increase code size 2019-11-15 22:25:54 +01:00
bpf_jit.h bpf, s390x: remove ld_abs/ld_ind 2018-05-03 16:49:20 -07:00
Makefile Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
pnet.c s390/net: convert pnetids to ascii 2019-02-21 10:34:37 -08:00