Commit fb9293b9 authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Heiko Carstens
Browse files

s390/vmem: remove unnecessary KASAN checks 



Kasan shadow memory area has been moved to the end of kernel address
space since commit 9a39abb7 ("s390/boot: simplify and fix kernel
memory layout setup"), therefore skipping any memory ranges above
VMALLOC_START in empty page tables cleanup code already handles
KASAN shadow memory intersection case and explicit checks could be
removed.

Reviewed-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent 108303b0

arch/s390/mm/vmem.c

+1 −12
Original line number Diff line number Diff line
@@ -297,10 +297,7 @@ static void try_free_pmd_table(pud_t *pud, unsigned long start) 
	/* Don't mess with any tables not fully in 1:1 mapping & vmemmap area */

	if (end > VMALLOC_START)

		return;

#ifdef CONFIG_KASAN

	if (start < KASAN_SHADOW_END && end > KASAN_SHADOW_START)

		return;

#endif



	pmd = pmd_offset(pud, start);

	for (i = 0; i < PTRS_PER_PMD; i++, pmd++)

		if (!pmd_none(*pmd))
@@ -372,10 +369,6 @@ static void try_free_pud_table(p4d_t *p4d, unsigned long start) 
	/* Don't mess with any tables not fully in 1:1 mapping & vmemmap area */

	if (end > VMALLOC_START)

		return;

#ifdef CONFIG_KASAN

	if (start < KASAN_SHADOW_END && end > KASAN_SHADOW_START)

		return;

#endif



	pud = pud_offset(p4d, start);

	for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
@@ -426,10 +419,6 @@ static void try_free_p4d_table(pgd_t *pgd, unsigned long start) 
	/* Don't mess with any tables not fully in 1:1 mapping & vmemmap area */

	if (end > VMALLOC_START)

		return;

#ifdef CONFIG_KASAN

	if (start < KASAN_SHADOW_END && end > KASAN_SHADOW_START)

		return;

#endif



	p4d = p4d_offset(pgd, start);

	for (i = 0; i < PTRS_PER_P4D; i++, p4d++) {