Commit 7c31c05e authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman

powerpc/kasan: Remove unnecessary page table locking

Commit 45ff3c55 ("powerpc/kasan: Fix parallel loading of
modules.") added spinlocks to manage parallele module loading.

Since then commit 47febbee ("powerpc/32: Force KASAN_VMALLOC for
modules") converted the module loading to KASAN_VMALLOC.

The spinlocking has then become unneeded and can be removed to
simplify kasan_init_shadow_page_tables()

Also remove inclusion of linux/moduleloader.h and linux/vmalloc.h
which are not needed anymore since the removal of modules management.
Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/81a4d3aee8b82bc1355595935c8f4ad9d3b22a83.1589866984.git.christophe.leroy@csgroup.eu
parent d2a91cef
...@@ -5,9 +5,7 @@ ...@@ -5,9 +5,7 @@
#include <linux/kasan.h> #include <linux/kasan.h>
#include <linux/printk.h> #include <linux/printk.h>
#include <linux/memblock.h> #include <linux/memblock.h>
#include <linux/moduleloader.h>
#include <linux/sched/task.h> #include <linux/sched/task.h>
#include <linux/vmalloc.h>
#include <asm/pgalloc.h> #include <asm/pgalloc.h>
#include <asm/code-patching.h> #include <asm/code-patching.h>
#include <mm/mmu_decl.h> #include <mm/mmu_decl.h>
...@@ -34,31 +32,22 @@ static int __init kasan_init_shadow_page_tables(unsigned long k_start, unsigned ...@@ -34,31 +32,22 @@ static int __init kasan_init_shadow_page_tables(unsigned long k_start, unsigned
{ {
pmd_t *pmd; pmd_t *pmd;
unsigned long k_cur, k_next; unsigned long k_cur, k_next;
pte_t *new = NULL;
pmd = pmd_ptr_k(k_start); pmd = pmd_ptr_k(k_start);
for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd++) { for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd++) {
pte_t *new;
k_next = pgd_addr_end(k_cur, k_end); k_next = pgd_addr_end(k_cur, k_end);
if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte) if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte)
continue; continue;
if (!new)
new = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE); new = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE);
if (!new) if (!new)
return -ENOMEM; return -ENOMEM;
kasan_populate_pte(new, PAGE_KERNEL); kasan_populate_pte(new, PAGE_KERNEL);
smp_wmb(); /* See comment in __pte_alloc */
spin_lock(&init_mm.page_table_lock);
/* Has another populated it ? */
if (likely((void *)pmd_page_vaddr(*pmd) == kasan_early_shadow_pte)) {
pmd_populate_kernel(&init_mm, pmd, new); pmd_populate_kernel(&init_mm, pmd, new);
new = NULL;
}
spin_unlock(&init_mm.page_table_lock);
} }
return 0; return 0;
} }
......
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