From: Alexandre Ghiti <alexandre.ghiti@xxxxxxxxxxxxx> commit a3d328037846d013bb4c7f3777241e190e4c75e1 upstream. In order to get the pfn of a struct page* when sparsemem is enabled without vmemmap, the mem_section structures need to be initialized which happens in sparse_init. But kasan_early_init calls pfn_to_page way before sparse_init is called, which then tries to dereference a null mem_section pointer. Fix this by removing the usage of this function in kasan_early_init. Fixes: 8ad8b72721d0 ("riscv: Add KASAN support") Signed-off-by: Alexandre Ghiti <alexandre.ghiti@xxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/riscv/mm/kasan_init.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -21,8 +21,7 @@ asmlinkage void __init kasan_early_init( for (i = 0; i < PTRS_PER_PTE; ++i) set_pte(kasan_early_shadow_pte + i, - mk_pte(virt_to_page(kasan_early_shadow_page), - PAGE_KERNEL)); + pfn_pte(virt_to_pfn(kasan_early_shadow_page), PAGE_KERNEL)); for (i = 0; i < PTRS_PER_PMD; ++i) set_pmd(kasan_early_shadow_pmd + i, Patches currently in stable-queue which might be from alexandre.ghiti@xxxxxxxxxxxxx are queue-5.10/riscv-fix-config-kasan-debug_virtual.patch queue-5.10/riscv-fix-config-kasan-sparsemem-sparse_vmemmap.patch