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-rw-r--r--arch/arm64/mm/proc.S270
1 files changed, 227 insertions, 43 deletions
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 95233dfc4c39..71baed7e592a 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]
@@ -116,7 +120,11 @@ ENTRY(cpu_do_resume)
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)
*
@@ -157,22 +186,201 @@ ENDPROC(cpu_do_switch_mm)
ENTRY(idmap_cpu_replace_ttbr1)
save_and_disable_daif flags=x2
- adrp x1, empty_zero_page
- msr ttbr1_el1, x1
+ __idmap_cpu_set_reserved_ttbr1 x1, x3
+
+ 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, next_\()\type // Skip invalid 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
+ __idmap_kpti_put_pgtable_ent_ng pgd
+next_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
- restore_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
+ __idmap_kpti_put_pgtable_ent_ng pud
+next_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
+ __idmap_kpti_put_pgtable_ent_ng pmd
+next_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
+next_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
@@ -180,7 +388,7 @@ 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
@@ -214,25 +422,19 @@ 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.
@@ -249,21 +451,3 @@ 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