On 12/10/18 1:15 PM, Kirill A. Shutemov wrote: > 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? >
You're right, terribly sorry. This was a last time change. mm/zsmalloc.c:256:21: error: variably modified ‘size_class’ at file scope I'll revisit the patch. Any other comments are welcome. Thank you
