On Mon, Dec 10, 2018 at 12:21:05PM -0200, Rafael David Tinoco wrote: > diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h > index 84bd9bdc1987..d808cfde3d19 100644 > --- a/arch/x86/include/asm/pgtable_64_types.h > +++ b/arch/x86/include/asm/pgtable_64_types.h > @@ -64,8 +64,6 @@ extern unsigned int ptrs_per_p4d; > #define P4D_SIZE (_AC(1, UL) << P4D_SHIFT) > #define P4D_MASK (~(P4D_SIZE - 1)) > > -#define MAX_POSSIBLE_PHYSMEM_BITS 52 > - > #else /* CONFIG_X86_5LEVEL */ > > /* > @@ -154,4 +152,6 @@ extern unsigned int ptrs_per_p4d; > > #define PGD_KERNEL_START ((PAGE_SIZE / 2) / sizeof(pgd_t)) > > +#define MAX_POSSIBLE_PHYSMEM_BITS (pgtable_l5_enabled() ? 52 : 46) > + ... > #endif /* _ASM_X86_PGTABLE_64_DEFS_H */ > diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > index 0787d33b80d8..132c20b6fd4f 100644 > --- a/mm/zsmalloc.c > +++ b/mm/zsmalloc.c ... > @@ -116,6 +100,25 @@ > */ > #define OBJ_ALLOCATED_TAG 1 > #define OBJ_TAG_BITS 1 > + > +/* > + * MAX_POSSIBLE_PHYSMEM_BITS should be defined by all archs using zsmalloc: > + * Trying to guess it from MAX_PHYSMEM_BITS, or considering it BITS_PER_LONG, > + * proved to be wrong by not considering PAE capabilities, or using SPARSEMEM > + * only headers, leading to bad object encoding due to object index overflow. > + */ > +#ifndef MAX_POSSIBLE_PHYSMEM_BITS > + #define MAX_POSSIBLE_PHYSMEM_BITS BITS_PER_LONG > + #error "MAX_POSSIBLE_PHYSMEM_BITS HAS to be defined by arch using zsmalloc"; > +#else > + #ifndef CONFIG_64BIT > + #if (MAX_POSSIBLE_PHYSMEM_BITS >= (BITS_PER_LONG + PAGE_SHIFT - OBJ_TAG_BITS)) > + #error "MAX_POSSIBLE_PHYSMEM_BITS is wrong for this arch"; > + #endif > + #endif > +#endif > + > +#define _PFN_BITS (MAX_POSSIBLE_PHYSMEM_BITS - PAGE_SHIFT) > #define OBJ_INDEX_BITS (BITS_PER_LONG - _PFN_BITS - OBJ_TAG_BITS) > #define OBJ_INDEX_MASK ((_AC(1, UL) << OBJ_INDEX_BITS) - 1) Have you tested it with CONFIG_X86_5LEVEL=y? ASAICS, the patch makes OBJ_INDEX_BITS and what depends from it dynamic -- it depends what paging mode we are booting in. ZS_SIZE_CLASSES depends indirectly on OBJ_INDEX_BITS and I don't see how struct zs_pool definition can compile with dynamic ZS_SIZE_CLASSES. Hm? -- Kirill A. Shutemov