Commit caa3cd5c authored by Vasily Gorbik's avatar Vasily Gorbik
Browse files

s390/kfence: Split kfence pool into 4k mappings in arch_kfence_init_pool() 



Since commit d08d4e7c ("s390/mm: use full 4KB page for 2KB PTE"),
there is no longer any reason to avoid splitting the kfence pool into
4k mappings in arch_kfence_init_pool(). Remove the architecture-specific
kfence_split_mapping().

Reviewed-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent d93a855c

arch/s390/include/asm/kfence.h

+3 −14
Original line number Diff line number Diff line
@@ -11,28 +11,17 @@ 
void __kernel_map_pages(struct page *page, int numpages, int enable);



static __always_inline bool arch_kfence_init_pool(void)

{

	return true;

}



#define arch_kfence_test_address(addr) ((addr) & PAGE_MASK)



/*

 * Do not split kfence pool to 4k mapping with arch_kfence_init_pool(),

 * but earlier where page table allocations still happen with memblock.

 * Reason is that arch_kfence_init_pool() gets called when the system

 * is still in a limbo state - disabling and enabling bottom halves is

 * not yet allowed, but that is what our page_table_alloc() would do.

 */

static __always_inline void kfence_split_mapping(void)

{

#ifdef CONFIG_KFENCE

	unsigned long pool_pages = KFENCE_POOL_SIZE >> PAGE_SHIFT;



	set_memory_4k((unsigned long)__kfence_pool, pool_pages);

#endif

	return true;

}



#define arch_kfence_test_address(addr) ((addr) & PAGE_MASK)



static inline bool kfence_protect_page(unsigned long addr, bool protect)

{

	__kernel_map_pages(virt_to_page((void *)addr), 1, !protect);

arch/s390/mm/init.c

+0 −1
Original line number Diff line number Diff line
@@ -175,7 +175,6 @@ void __init mem_init(void) 
        high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);



	pv_init();

	kfence_split_mapping();



	/* this will put all low memory onto the freelists */

	memblock_free_all();