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authorVasily Gorbik <gor@linux.ibm.com>2017-11-19 11:54:14 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2018-10-09 11:21:29 +0200
commit5dff03813f46f267bc1ecb334901e916346692ff (patch)
treee9bbcc7ed939aca9e7c180d7946e1f728bc7883c /arch/s390/mm
parent135ff163939294f5573927ca890699ed619c0031 (diff)
s390/kasan: add option for 4-level paging support
By default 3-level paging is used when the kernel is compiled with kasan support. Add 4-level paging option to support systems with more then 3TB of physical memory and to cover 4-level paging specific code with kasan as well. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/mm')
-rw-r--r--arch/s390/mm/kasan_init.c23
1 files changed, 17 insertions, 6 deletions
diff --git a/arch/s390/mm/kasan_init.c b/arch/s390/mm/kasan_init.c
index 40748afc43fa..5129847018ba 100644
--- a/arch/s390/mm/kasan_init.c
+++ b/arch/s390/mm/kasan_init.c
@@ -252,12 +252,23 @@ void __init kasan_early_init(void)
pgt_prot &= ~_PAGE_NOEXEC;
pte_z = __pte(__pa(kasan_zero_page) | pgt_prot);
- /* 3 level paging */
- BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PUD_SIZE));
- BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PUD_SIZE));
- crst_table_init((unsigned long *)early_pg_dir, _REGION3_ENTRY_EMPTY);
- untracked_mem_end = vmax = _REGION2_SIZE;
- asce_type = _ASCE_TYPE_REGION3;
+ if (IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)) {
+ /* 4 level paging */
+ BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, P4D_SIZE));
+ BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, P4D_SIZE));
+ crst_table_init((unsigned long *)early_pg_dir,
+ _REGION2_ENTRY_EMPTY);
+ untracked_mem_end = vmax = _REGION1_SIZE;
+ asce_type = _ASCE_TYPE_REGION2;
+ } else {
+ /* 3 level paging */
+ BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PUD_SIZE));
+ BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PUD_SIZE));
+ crst_table_init((unsigned long *)early_pg_dir,
+ _REGION3_ENTRY_EMPTY);
+ untracked_mem_end = vmax = _REGION2_SIZE;
+ asce_type = _ASCE_TYPE_REGION3;
+ }
/* init kasan zero shadow */
crst_table_init((unsigned long *)kasan_zero_p4d, p4d_val(p4d_z));