diff options
Diffstat (limited to 'arch/arm64/mm/proc.S')
| -rw-r--r-- | arch/arm64/mm/proc.S | 281 |
1 files changed, 234 insertions, 47 deletions
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 877d42fb0df6..c0af47617299 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -70,7 +70,11 @@ ENTRY(cpu_do_suspend) mrs x8, mdscr_el1 mrs x9, oslsr_el1 mrs x10, sctlr_el1 +alternative_if_not ARM64_HAS_VIRT_HOST_EXTN mrs x11, tpidr_el1 +alternative_else + mrs x11, tpidr_el2 +alternative_endif mrs x12, sp_el0 stp x2, x3, [x0] stp x4, xzr, [x0, #16] @@ -86,7 +90,7 @@ ENDPROC(cpu_do_suspend) * * x0: Address of context pointer */ - .pushsection ".idmap.text", "ax" + .pushsection ".idmap.text", "awx" ENTRY(cpu_do_resume) ldp x2, x3, [x0] ldp x4, x5, [x0, #16] @@ -109,14 +113,18 @@ ENTRY(cpu_do_resume) /* * __cpu_setup() cleared MDSCR_EL1.MDE and friends, before unmasking * debug exceptions. By restoring MDSCR_EL1 here, we may take a debug - * exception. Mask them until local_dbg_restore() in cpu_suspend() + * exception. Mask them until local_daif_restore() in cpu_suspend() * resets them. */ - disable_dbg + disable_daif msr mdscr_el1, x10 msr sctlr_el1, x12 +alternative_if_not ARM64_HAS_VIRT_HOST_EXTN msr tpidr_el1, x13 +alternative_else + msr tpidr_el2, x13 +alternative_endif msr sp_el0, x14 /* * Restore oslsr_el1 by writing oslar_el1 @@ -124,6 +132,11 @@ ENTRY(cpu_do_resume) ubfx x11, x11, #1, #1 msr oslar_el1, x11 reset_pmuserenr_el0 x0 // Disable PMU access from EL0 + +alternative_if ARM64_HAS_RAS_EXTN + msr_s SYS_DISR_EL1, xzr +alternative_else_nop_endif + isb ret ENDPROC(cpu_do_resume) @@ -138,16 +151,32 @@ ENDPROC(cpu_do_resume) * - pgd_phys - physical address of new TTB */ ENTRY(cpu_do_switch_mm) - pre_ttbr0_update_workaround x0, x2, x3 + mrs x2, ttbr1_el1 mmid x1, x1 // get mm->context.id - bfi x0, x1, #48, #16 // set the ASID - msr ttbr0_el1, x0 // set TTBR0 + phys_to_ttbr x3, x0 +#ifdef CONFIG_ARM64_SW_TTBR0_PAN + bfi x3, x1, #48, #16 // set the ASID field in TTBR0 +#endif + bfi x2, x1, #48, #16 // set the ASID + msr ttbr1_el1, x2 // in TTBR1 (since TCR.A1 is set) isb - post_ttbr0_update_workaround - ret + msr ttbr0_el1, x3 // now update TTBR0 + isb + b post_ttbr_update_workaround // Back to C code... ENDPROC(cpu_do_switch_mm) - .pushsection ".idmap.text", "ax" + .pushsection ".idmap.text", "awx" + +.macro __idmap_cpu_set_reserved_ttbr1, tmp1, tmp2 + adrp \tmp1, empty_zero_page + phys_to_ttbr \tmp2, \tmp1 + msr ttbr1_el1, \tmp2 + isb + tlbi vmalle1 + dsb nsh + isb +.endm + /* * void idmap_cpu_replace_ttbr1(phys_addr_t new_pgd) * @@ -155,25 +184,207 @@ ENDPROC(cpu_do_switch_mm) * called by anything else. It can only be executed from a TTBR0 mapping. */ ENTRY(idmap_cpu_replace_ttbr1) - mrs x2, daif - msr daifset, #0xf + save_and_disable_daif flags=x2 + + __idmap_cpu_set_reserved_ttbr1 x1, x3 - adrp x1, empty_zero_page - msr ttbr1_el1, x1 + phys_to_ttbr x3, x0 + msr ttbr1_el1, x3 isb - tlbi vmalle1 - dsb nsh + restore_daif x2 + + ret +ENDPROC(idmap_cpu_replace_ttbr1) + .popsection + +#ifdef CONFIG_UNMAP_KERNEL_AT_EL0 + .pushsection ".idmap.text", "awx" + + .macro __idmap_kpti_get_pgtable_ent, type + dc cvac, cur_\()\type\()p // Ensure any existing dirty + dmb sy // lines are written back before + ldr \type, [cur_\()\type\()p] // loading the entry + tbz \type, #0, skip_\()\type // Skip invalid and + tbnz \type, #11, skip_\()\type // non-global entries + .endm + + .macro __idmap_kpti_put_pgtable_ent_ng, type + orr \type, \type, #PTE_NG // Same bit for blocks and pages + str \type, [cur_\()\type\()p] // Update the entry and ensure it + dc civac, cur_\()\type\()p // is visible to all CPUs. + .endm + +/* + * void __kpti_install_ng_mappings(int cpu, int num_cpus, phys_addr_t swapper) + * + * Called exactly once from stop_machine context by each CPU found during boot. + */ +__idmap_kpti_flag: + .long 1 +ENTRY(idmap_kpti_install_ng_mappings) + cpu .req w0 + num_cpus .req w1 + swapper_pa .req x2 + swapper_ttb .req x3 + flag_ptr .req x4 + cur_pgdp .req x5 + end_pgdp .req x6 + pgd .req x7 + cur_pudp .req x8 + end_pudp .req x9 + pud .req x10 + cur_pmdp .req x11 + end_pmdp .req x12 + pmd .req x13 + cur_ptep .req x14 + end_ptep .req x15 + pte .req x16 + + mrs swapper_ttb, ttbr1_el1 + adr flag_ptr, __idmap_kpti_flag + + cbnz cpu, __idmap_kpti_secondary + + /* We're the boot CPU. Wait for the others to catch up */ + sevl +1: wfe + ldaxr w18, [flag_ptr] + eor w18, w18, num_cpus + cbnz w18, 1b + + /* We need to walk swapper, so turn off the MMU. */ + pre_disable_mmu_workaround + mrs x18, sctlr_el1 + bic x18, x18, #SCTLR_ELx_M + msr sctlr_el1, x18 isb - msr ttbr1_el1, x0 + /* Everybody is enjoying the idmap, so we can rewrite swapper. */ + /* PGD */ + mov cur_pgdp, swapper_pa + add end_pgdp, cur_pgdp, #(PTRS_PER_PGD * 8) +do_pgd: __idmap_kpti_get_pgtable_ent pgd + tbnz pgd, #1, walk_puds +next_pgd: + __idmap_kpti_put_pgtable_ent_ng pgd +skip_pgd: + add cur_pgdp, cur_pgdp, #8 + cmp cur_pgdp, end_pgdp + b.ne do_pgd + + /* Publish the updated tables and nuke all the TLBs */ + dsb sy + tlbi vmalle1is + dsb ish isb - msr daif, x2 + /* We're done: fire up the MMU again */ + mrs x18, sctlr_el1 + orr x18, x18, #SCTLR_ELx_M + msr sctlr_el1, x18 + isb + /* Set the flag to zero to indicate that we're all done */ + str wzr, [flag_ptr] ret -ENDPROC(idmap_cpu_replace_ttbr1) + + /* PUD */ +walk_puds: + .if CONFIG_PGTABLE_LEVELS > 3 + pte_to_phys cur_pudp, pgd + add end_pudp, cur_pudp, #(PTRS_PER_PUD * 8) +do_pud: __idmap_kpti_get_pgtable_ent pud + tbnz pud, #1, walk_pmds +next_pud: + __idmap_kpti_put_pgtable_ent_ng pud +skip_pud: + add cur_pudp, cur_pudp, 8 + cmp cur_pudp, end_pudp + b.ne do_pud + b next_pgd + .else /* CONFIG_PGTABLE_LEVELS <= 3 */ + mov pud, pgd + b walk_pmds +next_pud: + b next_pgd + .endif + + /* PMD */ +walk_pmds: + .if CONFIG_PGTABLE_LEVELS > 2 + pte_to_phys cur_pmdp, pud + add end_pmdp, cur_pmdp, #(PTRS_PER_PMD * 8) +do_pmd: __idmap_kpti_get_pgtable_ent pmd + tbnz pmd, #1, walk_ptes +next_pmd: + __idmap_kpti_put_pgtable_ent_ng pmd +skip_pmd: + add cur_pmdp, cur_pmdp, #8 + cmp cur_pmdp, end_pmdp + b.ne do_pmd + b next_pud + .else /* CONFIG_PGTABLE_LEVELS <= 2 */ + mov pmd, pud + b walk_ptes +next_pmd: + b next_pud + .endif + + /* PTE */ +walk_ptes: + pte_to_phys cur_ptep, pmd + add end_ptep, cur_ptep, #(PTRS_PER_PTE * 8) +do_pte: __idmap_kpti_get_pgtable_ent pte + __idmap_kpti_put_pgtable_ent_ng pte +skip_pte: + add cur_ptep, cur_ptep, #8 + cmp cur_ptep, end_ptep + b.ne do_pte + b next_pmd + + /* Secondary CPUs end up here */ +__idmap_kpti_secondary: + /* Uninstall swapper before surgery begins */ + __idmap_cpu_set_reserved_ttbr1 x18, x17 + + /* Increment the flag to let the boot CPU we're ready */ +1: ldxr w18, [flag_ptr] + add w18, w18, #1 + stxr w17, w18, [flag_ptr] + cbnz w17, 1b + + /* Wait for the boot CPU to finish messing around with swapper */ + sevl +1: wfe + ldxr w18, [flag_ptr] + cbnz w18, 1b + + /* All done, act like nothing happened */ + msr ttbr1_el1, swapper_ttb + isb + ret + + .unreq cpu + .unreq num_cpus + .unreq swapper_pa + .unreq swapper_ttb + .unreq flag_ptr + .unreq cur_pgdp + .unreq end_pgdp + .unreq pgd + .unreq cur_pudp + .unreq end_pudp + .unreq pud + .unreq cur_pmdp + .unreq end_pmdp + .unreq pmd + .unreq cur_ptep + .unreq end_ptep + .unreq pte +ENDPROC(idmap_kpti_install_ng_mappings) .popsection +#endif /* * __cpu_setup @@ -181,7 +392,7 @@ ENDPROC(idmap_cpu_replace_ttbr1) * Initialise the processor for turning the MMU on. Return in x0 the * value of the SCTLR_EL1 register. */ - .pushsection ".idmap.text", "ax" + .pushsection ".idmap.text", "awx" ENTRY(__cpu_setup) tlbi vmalle1 // Invalidate local TLB dsb nsh @@ -215,25 +426,19 @@ ENTRY(__cpu_setup) /* * Prepare SCTLR */ - adr x5, crval - ldp w5, w6, [x5] - mrs x0, sctlr_el1 - bic x0, x0, x5 // clear bits - orr x0, x0, x6 // set bits + mov_q x0, SCTLR_EL1_SET /* * Set/prepare TCR and TTBR. We use 512GB (39-bit) address range for * both user and kernel. */ ldr x10, =TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \ - TCR_TG_FLAGS | TCR_ASID16 | TCR_TBI0 + TCR_TG_FLAGS | TCR_ASID16 | TCR_TBI0 | TCR_A1 tcr_set_idmap_t0sz x10, x9 /* - * Read the PARange bits from ID_AA64MMFR0_EL1 and set the IPS bits in - * TCR_EL1. + * Set the IPS bits in TCR_EL1. */ - mrs x9, ID_AA64MMFR0_EL1 - bfi x10, x9, #32, #3 + tcr_compute_pa_size x10, #TCR_IPS_SHIFT, x5, x6 #ifdef CONFIG_ARM64_HW_AFDBM /* * Hardware update of the Access and Dirty bits. @@ -250,21 +455,3 @@ ENTRY(__cpu_setup) msr tcr_el1, x10 ret // return to head.S ENDPROC(__cpu_setup) - - /* - * We set the desired value explicitly, including those of the - * reserved bits. The values of bits EE & E0E were set early in - * el2_setup, which are left untouched below. - * - * n n T - * U E WT T UD US IHBS - * CE0 XWHW CZ ME TEEA S - * .... .IEE .... NEAI TE.I ..AD DEN0 ACAM - * 0011 0... 1101 ..0. ..0. 10.. .0.. .... < hardware reserved - * .... .1.. .... 01.1 11.1 ..01 0.01 1101 < software settings - */ - .type crval, #object -crval: - .word 0xfcffffff // clear - .word 0x34d5d91d // set - .popsection |