From 2da073c19641bb6820c3591d3d865120263f14e8 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Sat, 13 Mar 2021 03:45:05 -0500 Subject: [PATCH] riscv: Cleanup KASAN_VMALLOC support When KASAN vmalloc region is populated, there is no userspace process and the page table in use is swapper_pg_dir, so there is no need to read SATP. Then we can use the same scheme used by kasan_populate_p*d functions to go through the page table, which harmonizes the code. In addition, make use of set_pgd that goes through all unused page table levels, contrary to p*d_populate functions, which makes this function work whatever the number of page table levels. Signed-off-by: Alexandre Ghiti Reviewed-by: Palmer Dabbelt Signed-off-by: Palmer Dabbelt --- arch/riscv/mm/kasan_init.c | 59 ++++++++++++++-------------------------------- 1 file changed, 18 insertions(+), 41 deletions(-) diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c index 3fc18f4..2c39f03 100644 --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -11,18 +11,6 @@ #include #include -static __init void *early_alloc(size_t size, int node) -{ - void *ptr = memblock_alloc_try_nid(size, size, - __pa(MAX_DMA_ADDRESS), MEMBLOCK_ALLOC_ACCESSIBLE, node); - - if (!ptr) - panic("%pS: Failed to allocate %zu bytes align=%zx nid=%d from=%llx\n", - __func__, size, size, node, (u64)__pa(MAX_DMA_ADDRESS)); - - return ptr; -} - extern pgd_t early_pg_dir[PTRS_PER_PGD]; asmlinkage void __init kasan_early_init(void) { @@ -155,38 +143,27 @@ static void __init kasan_populate(void *start, void *end) memset(start, KASAN_SHADOW_INIT, end - start); } -void __init kasan_shallow_populate(void *start, void *end) +static void __init kasan_shallow_populate_pgd(unsigned long vaddr, unsigned long end) { - unsigned long vaddr = (unsigned long)start & PAGE_MASK; - unsigned long vend = PAGE_ALIGN((unsigned long)end); - unsigned long pfn; - int index; + unsigned long next; void *p; - pud_t *pud_dir, *pud_k; - pgd_t *pgd_dir, *pgd_k; - p4d_t *p4d_dir, *p4d_k; - - while (vaddr < vend) { - index = pgd_index(vaddr); - pfn = csr_read(CSR_SATP) & SATP_PPN; - pgd_dir = (pgd_t *)pfn_to_virt(pfn) + index; - pgd_k = init_mm.pgd + index; - pgd_dir = pgd_offset_k(vaddr); - set_pgd(pgd_dir, *pgd_k); - - p4d_dir = p4d_offset(pgd_dir, vaddr); - p4d_k = p4d_offset(pgd_k, vaddr); - - vaddr = (vaddr + PUD_SIZE) & PUD_MASK; - pud_dir = pud_offset(p4d_dir, vaddr); - pud_k = pud_offset(p4d_k, vaddr); - - if (pud_present(*pud_dir)) { - p = early_alloc(PAGE_SIZE, NUMA_NO_NODE); - pud_populate(&init_mm, pud_dir, p); + pgd_t *pgd_k = pgd_offset_k(vaddr); + + do { + next = pgd_addr_end(vaddr, end); + if (pgd_page_vaddr(*pgd_k) == (unsigned long)lm_alias(kasan_early_shadow_pmd)) { + p = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + set_pgd(pgd_k, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE)); } - vaddr += PAGE_SIZE; - } + } while (pgd_k++, vaddr = next, vaddr != end); +} + +static void __init kasan_shallow_populate(void *start, void *end) +{ + unsigned long vaddr = (unsigned long)start & PAGE_MASK; + unsigned long vend = PAGE_ALIGN((unsigned long)end); + + kasan_shallow_populate_pgd(vaddr, vend); } void __init kasan_init(void) -- 2.7.4