diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index d103c3ee7335..ba609e0439e8 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -543,6 +543,29 @@ USER(\label, ic ivau, \tmp2) // invalidate I line PoU mrs \rd, sp_el0 .endm +/* + * Offset ttbr1 to allow for 48-bit kernel VAs set with 52-bit PTRS_PER_PGD. + * orr is used as it can cover the immediate value (and is idempotent). + * In future this may be nop'ed out when dealing with 52-bit kernel VAs. + * ttbr: Value of ttbr to set, modified. + */ + .macro offset_ttbr1, ttbr +#ifdef CONFIG_ARM64_52BIT_VA + orr \ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET +#endif + .endm + +/* + * Perform the reverse of offset_ttbr1. + * bic is used as it can cover the immediate value and, in future, won't need + * to be nop'ed out when dealing with 52-bit kernel VAs. + */ + .macro restore_ttbr1, ttbr +#ifdef CONFIG_ARM64_52BIT_VA + bic \ttbr, \ttbr, #TTBR1_BADDR_4852_OFFSET +#endif + .endm + /* * Arrange a physical address in a TTBR register, taking care of 52-bit * addresses. diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index 1d7d8da2ef9b..d5219f2624b7 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -80,7 +80,11 @@ #define PGDIR_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(4 - CONFIG_PGTABLE_LEVELS) #define PGDIR_SIZE (_AC(1, UL) << PGDIR_SHIFT) #define PGDIR_MASK (~(PGDIR_SIZE-1)) +#ifdef CONFIG_ARM64_52BIT_VA +#define PTRS_PER_PGD (1 << (52 - PGDIR_SHIFT)) +#else #define PTRS_PER_PGD (1 << (VA_BITS - PGDIR_SHIFT)) +#endif /* * Section address mask and size definitions. @@ -306,4 +310,10 @@ #define TTBR_BADDR_MASK_52 (((UL(1) << 46) - 1) << 2) #endif +#ifdef CONFIG_ARM64_52BIT_VA +/* Must be at least 64-byte aligned to prevent corruption of the TTBR */ +#define TTBR1_BADDR_4852_OFFSET (((UL(1) << (52 - PGDIR_SHIFT)) - \ + (UL(1) << (48 - PGDIR_SHIFT))) * 8) +#endif + #endif diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 4471f570a295..f60081be9a1b 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -769,6 +769,7 @@ ENTRY(__enable_mmu) phys_to_ttbr x1, x1 phys_to_ttbr x2, x2 msr ttbr0_el1, x2 // load TTBR0 + offset_ttbr1 x1 msr ttbr1_el1, x1 // load TTBR1 isb msr sctlr_el1, x0 diff --git a/arch/arm64/kernel/hibernate-asm.S b/arch/arm64/kernel/hibernate-asm.S index dd14ab8c9f72..fe36d85c60bd 100644 --- a/arch/arm64/kernel/hibernate-asm.S +++ b/arch/arm64/kernel/hibernate-asm.S @@ -40,6 +40,7 @@ tlbi vmalle1 dsb nsh phys_to_ttbr \tmp, \page_table + offset_ttbr1 \tmp msr ttbr1_el1, \tmp isb .endm diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 2c75b0b903ae..2db1c491d45d 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -182,6 +182,7 @@ ENDPROC(cpu_do_switch_mm) .macro __idmap_cpu_set_reserved_ttbr1, tmp1, tmp2 adrp \tmp1, empty_zero_page phys_to_ttbr \tmp2, \tmp1 + offset_ttbr1 \tmp2 msr ttbr1_el1, \tmp2 isb tlbi vmalle1 @@ -200,6 +201,7 @@ ENTRY(idmap_cpu_replace_ttbr1) __idmap_cpu_set_reserved_ttbr1 x1, x3 + offset_ttbr1 x0 msr ttbr1_el1, x0 isb @@ -254,6 +256,7 @@ ENTRY(idmap_kpti_install_ng_mappings) pte .req x16 mrs swapper_ttb, ttbr1_el1 + restore_ttbr1 swapper_ttb adr flag_ptr, __idmap_kpti_flag cbnz cpu, __idmap_kpti_secondary @@ -373,6 +376,7 @@ __idmap_kpti_secondary: cbnz w18, 1b /* All done, act like nothing happened */ + offset_ttbr1 swapper_ttb msr ttbr1_el1, swapper_ttb isb ret