From fb9293b9f32d01ee491606a3655054d539b89f66 Mon Sep 17 00:00:00 2001
From: Vasily Gorbik <gor@linux.ibm.com>
Date: Sat, 28 Jan 2023 18:06:40 +0100
Subject: [PATCH] s390/vmem: remove unnecessary KASAN checks
Kasan shadow memory area has been moved to the end of kernel address
space since commit 9a39abb7c9aa ("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: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---
arch/s390/mm/vmem.c | 13 +------------
1 file changed, 1 insertion(+), 12 deletions(-)
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index 10bf5fcbb508..4113a7ffa149 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -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++) {