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s390/vmem: fix empty page tables cleanup under KASAN

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Commit b9ff81003cf1 ("s390/vmem: cleanup empty page tables") introduced
empty page tables cleanup in vmem code, but when the kernel is built
with KASAN enabled the code has no effect due to wrong KASAN shadow
memory intersection condition, which effectively ignores any memory
range below KASAN shadow. Fix intersection condition to make code
work as anticipated.

Fixes: b9ff81003cf1 ("s390/vmem: cleanup empty page tables")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This commit is contained in:
Vasily Gorbik 2023-01-28 17:35:12 +01:00 committed by Heiko Carstens
parent dfca37d36b
commit 108303b0a2
1 changed files with 3 additions and 3 deletions
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6
arch/s390/mm/vmem.c
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@ -298,7 +298,7 @@ static void try_free_pmd_table(pud_t *pud, unsigned long start)
if (end > VMALLOC_START)
return;
#ifdef CONFIG_KASAN
if (start < KASAN_SHADOW_END && KASAN_SHADOW_START > end)
if (start < KASAN_SHADOW_END && end > KASAN_SHADOW_START)
return;
#endif
pmd = pmd_offset(pud, start);
@ -373,7 +373,7 @@ static void try_free_pud_table(p4d_t *p4d, unsigned long start)
if (end > VMALLOC_START)
return;
#ifdef CONFIG_KASAN
if (start < KASAN_SHADOW_END && KASAN_SHADOW_START > end)
if (start < KASAN_SHADOW_END && end > KASAN_SHADOW_START)
return;
#endif
@ -427,7 +427,7 @@ static void try_free_p4d_table(pgd_t *pgd, unsigned long start)
if (end > VMALLOC_START)
return;
#ifdef CONFIG_KASAN
if (start < KASAN_SHADOW_END && KASAN_SHADOW_START > end)
if (start < KASAN_SHADOW_END && end > KASAN_SHADOW_START)
return;
#endif