arm64: Remove the !CONFIG_ARM64_HW_AFDBM alternative code paths

Since the pte handling for hardware AF/DBM works even when the hardware
feature is not present, make the pte accessors implementation permanent
and remove the corresponding #ifdefs. The Kconfig option is kept as it
can still be used to disable the feature at the hardware level.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit af29678fe785ad79e7386e97b57093482f0dd7c4)

CVE-2017-5753
CVE-2017-5715
CVE-2017-5754

Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 62b62f4c39e89fadef686e4c954b46c12268a855..b46e54c2399b58b6451ea9dacc5c033115b05c64 100644 (file)
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -85,11 +85,7 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
        (__boundary - 1 < (end) - 1) ? __boundary : (end);                      \
 })
 
-#ifdef CONFIG_ARM64_HW_AFDBM
 #define pte_hw_dirty(pte)      (pte_write(pte) && !(pte_val(pte) & PTE_RDONLY))
-#else
-#define pte_hw_dirty(pte)      (0)
-#endif
 #define pte_sw_dirty(pte)      (!!(pte_val(pte) & PTE_DIRTY))
 #define pte_dirty(pte)         (pte_sw_dirty(pte) || pte_hw_dirty(pte))
 
@@ -228,8 +224,7 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
         * hardware updates of the pte (ptep_set_access_flags safely changes
         * valid ptes without going through an invalid entry).
         */
-       if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM) &&
-           pte_valid(*ptep) && pte_valid(pte)) {
+       if (pte_valid(*ptep) && pte_valid(pte)) {
                VM_WARN_ONCE(!pte_young(pte),
                             "%s: racy access flag clearing: 0x%016llx -> 0x%016llx",
                             __func__, pte_val(*ptep), pte_val(pte));
@@ -565,7 +560,6 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
        return pte_pmd(pte_modify(pmd_pte(pmd), newprot));
 }
 
-#ifdef CONFIG_ARM64_HW_AFDBM
 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
 extern int ptep_set_access_flags(struct vm_area_struct *vma,
                                 unsigned long address, pte_t *ptep,
@@ -670,7 +664,6 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
        ptep_set_wrprotect(mm, address, (pte_t *)pmdp);
 }
 #endif
-#endif /* CONFIG_ARM64_HW_AFDBM */
 
 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];

diff --git a/arch/arm64/kvm/hyp/s2-setup.c b/arch/arm64/kvm/hyp/s2-setup.c
index b81f4091c909ce1e2650986648cdde1e2d1a23d0..a81f5e10fc8c14d20d6d76a78dde74c368ce7ef8 100644 (file)
--- a/arch/arm64/kvm/hyp/s2-setup.c
+++ b/arch/arm64/kvm/hyp/s2-setup.c
@@ -70,7 +70,7 @@ u32 __hyp_text __init_stage2_translation(void)
         * Management in ID_AA64MMFR1_EL1 and enable the feature in VTCR_EL2.
         */
        tmp = (read_sysreg(id_aa64mmfr1_el1) >> ID_AA64MMFR1_HADBS_SHIFT) & 0xf;
-       if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM) && tmp)
+       if (tmp)
                val |= VTCR_EL2_HA;
 
        /*

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 738154b09562b7605e532823dc800b115831384f..a7c5196e2eaba48ec37e51fa1b2f7e28a17c9233 100644 (file)
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -140,7 +140,6 @@ void show_pte(unsigned long addr)
        pr_cont("\n");
 }
 
-#ifdef CONFIG_ARM64_HW_AFDBM
 /*
  * This function sets the access flags (dirty, accessed), as well as write
  * permission, and only to a more permissive setting.
@@ -182,7 +181,6 @@ int ptep_set_access_flags(struct vm_area_struct *vma,
        flush_tlb_fix_spurious_fault(vma, address);
        return 1;
 }
-#endif
 
 static bool is_el1_instruction_abort(unsigned int esr)
 {