diff options
| author | Heiko Carstens <hca@linux.ibm.com> | 2023-08-25 14:29:48 +0200 |
|---|---|---|
| committer | Heiko Carstens <hca@linux.ibm.com> | 2023-08-30 11:03:27 +0200 |
| commit | c0f1d478121131c2a97cab24148bf7ebb7ed3434 (patch) | |
| tree | eddcdda865a0d66f371590e057025128c32af7d5 /arch/s390/kernel/early.c | |
| parent | b6f10e2f66e43b903b1f37b643d353fe364190cd (diff) | |
s390/mm: simplify kernel mapping setup
The kernel mapping is setup in two stages: in the decompressor map all
pages with RWX permissions, and within the kernel change all mappings to
their final permissions, where most of the mappings are changed from RWX to
RWNX.
Change this and map all pages RWNX from the beginning, however without
enabling noexec via control register modification. This means that
effectively all pages are used with RWX permissions like before. When the
final permissions have been applied to the kernel mapping enable noexec via
control register modification.
This allows to remove quite a bit of non-obvious code.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Diffstat (limited to 'arch/s390/kernel/early.c')
| -rw-r--r-- | arch/s390/kernel/early.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index 3dccc6eb24a8..442ce0489e1a 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -232,10 +232,8 @@ static __init void detect_machine_facilities(void) S390_lowcore.machine_flags |= MACHINE_FLAG_VX; __ctl_set_bit(0, 17); } - if (test_facility(130)) { + if (test_facility(130)) S390_lowcore.machine_flags |= MACHINE_FLAG_NX; - __ctl_set_bit(0, 20); - } if (test_facility(133)) S390_lowcore.machine_flags |= MACHINE_FLAG_GS; if (test_facility(139) && (tod_clock_base.tod >> 63)) { |