summaryrefslogtreecommitdiff
path: root/arch/arm64/mm
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/mm')
-rw-r--r--arch/arm64/mm/Makefile1
-rw-r--r--arch/arm64/mm/contpte.c408
-rw-r--r--arch/arm64/mm/fault.c42
-rw-r--r--arch/arm64/mm/fixmap.c43
-rw-r--r--arch/arm64/mm/hugetlbpage.c47
-rw-r--r--arch/arm64/mm/init.c4
-rw-r--r--arch/arm64/mm/kasan_init.c165
-rw-r--r--arch/arm64/mm/mmap.c4
-rw-r--r--arch/arm64/mm/mmu.c275
-rw-r--r--arch/arm64/mm/pageattr.c6
-rw-r--r--arch/arm64/mm/pgd.c17
-rw-r--r--arch/arm64/mm/proc.S116
-rw-r--r--arch/arm64/mm/ptdump.c88
-rw-r--r--arch/arm64/mm/trans_pgd.c6
14 files changed, 911 insertions, 311 deletions
diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile
index dbd1bc95967d..60454256945b 100644
--- a/arch/arm64/mm/Makefile
+++ b/arch/arm64/mm/Makefile
@@ -3,6 +3,7 @@ obj-y := dma-mapping.o extable.o fault.o init.o \
cache.o copypage.o flush.o \
ioremap.o mmap.o pgd.o mmu.o \
context.o proc.o pageattr.o fixmap.o
+obj-$(CONFIG_ARM64_CONTPTE) += contpte.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_PTDUMP_CORE) += ptdump.o
obj-$(CONFIG_PTDUMP_DEBUGFS) += ptdump_debugfs.o
diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c
new file mode 100644
index 000000000000..1b64b4c3f8bf
--- /dev/null
+++ b/arch/arm64/mm/contpte.c
@@ -0,0 +1,408 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2023 ARM Ltd.
+ */
+
+#include <linux/mm.h>
+#include <linux/efi.h>
+#include <linux/export.h>
+#include <asm/tlbflush.h>
+
+static inline bool mm_is_user(struct mm_struct *mm)
+{
+ /*
+ * Don't attempt to apply the contig bit to kernel mappings, because
+ * dynamically adding/removing the contig bit can cause page faults.
+ * These racing faults are ok for user space, since they get serialized
+ * on the PTL. But kernel mappings can't tolerate faults.
+ */
+ if (unlikely(mm_is_efi(mm)))
+ return false;
+ return mm != &init_mm;
+}
+
+static inline pte_t *contpte_align_down(pte_t *ptep)
+{
+ return PTR_ALIGN_DOWN(ptep, sizeof(*ptep) * CONT_PTES);
+}
+
+static void contpte_try_unfold_partial(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned int nr)
+{
+ /*
+ * Unfold any partially covered contpte block at the beginning and end
+ * of the range.
+ */
+
+ if (ptep != contpte_align_down(ptep) || nr < CONT_PTES)
+ contpte_try_unfold(mm, addr, ptep, __ptep_get(ptep));
+
+ if (ptep + nr != contpte_align_down(ptep + nr)) {
+ unsigned long last_addr = addr + PAGE_SIZE * (nr - 1);
+ pte_t *last_ptep = ptep + nr - 1;
+
+ contpte_try_unfold(mm, last_addr, last_ptep,
+ __ptep_get(last_ptep));
+ }
+}
+
+static void contpte_convert(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ struct vm_area_struct vma = TLB_FLUSH_VMA(mm, 0);
+ unsigned long start_addr;
+ pte_t *start_ptep;
+ int i;
+
+ start_ptep = ptep = contpte_align_down(ptep);
+ start_addr = addr = ALIGN_DOWN(addr, CONT_PTE_SIZE);
+ pte = pfn_pte(ALIGN_DOWN(pte_pfn(pte), CONT_PTES), pte_pgprot(pte));
+
+ for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE) {
+ pte_t ptent = __ptep_get_and_clear(mm, addr, ptep);
+
+ if (pte_dirty(ptent))
+ pte = pte_mkdirty(pte);
+
+ if (pte_young(ptent))
+ pte = pte_mkyoung(pte);
+ }
+
+ __flush_tlb_range(&vma, start_addr, addr, PAGE_SIZE, true, 3);
+
+ __set_ptes(mm, start_addr, start_ptep, pte, CONT_PTES);
+}
+
+void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ /*
+ * We have already checked that the virtual and pysical addresses are
+ * correctly aligned for a contpte mapping in contpte_try_fold() so the
+ * remaining checks are to ensure that the contpte range is fully
+ * covered by a single folio, and ensure that all the ptes are valid
+ * with contiguous PFNs and matching prots. We ignore the state of the
+ * access and dirty bits for the purpose of deciding if its a contiguous
+ * range; the folding process will generate a single contpte entry which
+ * has a single access and dirty bit. Those 2 bits are the logical OR of
+ * their respective bits in the constituent pte entries. In order to
+ * ensure the contpte range is covered by a single folio, we must
+ * recover the folio from the pfn, but special mappings don't have a
+ * folio backing them. Fortunately contpte_try_fold() already checked
+ * that the pte is not special - we never try to fold special mappings.
+ * Note we can't use vm_normal_page() for this since we don't have the
+ * vma.
+ */
+
+ unsigned long folio_start, folio_end;
+ unsigned long cont_start, cont_end;
+ pte_t expected_pte, subpte;
+ struct folio *folio;
+ struct page *page;
+ unsigned long pfn;
+ pte_t *orig_ptep;
+ pgprot_t prot;
+
+ int i;
+
+ if (!mm_is_user(mm))
+ return;
+
+ page = pte_page(pte);
+ folio = page_folio(page);
+ folio_start = addr - (page - &folio->page) * PAGE_SIZE;
+ folio_end = folio_start + folio_nr_pages(folio) * PAGE_SIZE;
+ cont_start = ALIGN_DOWN(addr, CONT_PTE_SIZE);
+ cont_end = cont_start + CONT_PTE_SIZE;
+
+ if (folio_start > cont_start || folio_end < cont_end)
+ return;
+
+ pfn = ALIGN_DOWN(pte_pfn(pte), CONT_PTES);
+ prot = pte_pgprot(pte_mkold(pte_mkclean(pte)));
+ expected_pte = pfn_pte(pfn, prot);
+ orig_ptep = ptep;
+ ptep = contpte_align_down(ptep);
+
+ for (i = 0; i < CONT_PTES; i++) {
+ subpte = pte_mkold(pte_mkclean(__ptep_get(ptep)));
+ if (!pte_same(subpte, expected_pte))
+ return;
+ expected_pte = pte_advance_pfn(expected_pte, 1);
+ ptep++;
+ }
+
+ pte = pte_mkcont(pte);
+ contpte_convert(mm, addr, orig_ptep, pte);
+}
+EXPORT_SYMBOL_GPL(__contpte_try_fold);
+
+void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
+{
+ /*
+ * We have already checked that the ptes are contiguous in
+ * contpte_try_unfold(), so just check that the mm is user space.
+ */
+ if (!mm_is_user(mm))
+ return;
+
+ pte = pte_mknoncont(pte);
+ contpte_convert(mm, addr, ptep, pte);
+}
+EXPORT_SYMBOL_GPL(__contpte_try_unfold);
+
+pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte)
+{
+ /*
+ * Gather access/dirty bits, which may be populated in any of the ptes
+ * of the contig range. We are guaranteed to be holding the PTL, so any
+ * contiguous range cannot be unfolded or otherwise modified under our
+ * feet.
+ */
+
+ pte_t pte;
+ int i;
+
+ ptep = contpte_align_down(ptep);
+
+ for (i = 0; i < CONT_PTES; i++, ptep++) {
+ pte = __ptep_get(ptep);
+
+ if (pte_dirty(pte))
+ orig_pte = pte_mkdirty(orig_pte);
+
+ if (pte_young(pte))
+ orig_pte = pte_mkyoung(orig_pte);
+ }
+
+ return orig_pte;
+}
+EXPORT_SYMBOL_GPL(contpte_ptep_get);
+
+pte_t contpte_ptep_get_lockless(pte_t *orig_ptep)
+{
+ /*
+ * The ptep_get_lockless() API requires us to read and return *orig_ptep
+ * so that it is self-consistent, without the PTL held, so we may be
+ * racing with other threads modifying the pte. Usually a READ_ONCE()
+ * would suffice, but for the contpte case, we also need to gather the
+ * access and dirty bits from across all ptes in the contiguous block,
+ * and we can't read all of those neighbouring ptes atomically, so any
+ * contiguous range may be unfolded/modified/refolded under our feet.
+ * Therefore we ensure we read a _consistent_ contpte range by checking
+ * that all ptes in the range are valid and have CONT_PTE set, that all
+ * pfns are contiguous and that all pgprots are the same (ignoring
+ * access/dirty). If we find a pte that is not consistent, then we must
+ * be racing with an update so start again. If the target pte does not
+ * have CONT_PTE set then that is considered consistent on its own
+ * because it is not part of a contpte range.
+ */
+
+ pgprot_t orig_prot;
+ unsigned long pfn;
+ pte_t orig_pte;
+ pgprot_t prot;
+ pte_t *ptep;
+ pte_t pte;
+ int i;
+
+retry:
+ orig_pte = __ptep_get(orig_ptep);
+
+ if (!pte_valid_cont(orig_pte))
+ return orig_pte;
+
+ orig_prot = pte_pgprot(pte_mkold(pte_mkclean(orig_pte)));
+ ptep = contpte_align_down(orig_ptep);
+ pfn = pte_pfn(orig_pte) - (orig_ptep - ptep);
+
+ for (i = 0; i < CONT_PTES; i++, ptep++, pfn++) {
+ pte = __ptep_get(ptep);
+ prot = pte_pgprot(pte_mkold(pte_mkclean(pte)));
+
+ if (!pte_valid_cont(pte) ||
+ pte_pfn(pte) != pfn ||
+ pgprot_val(prot) != pgprot_val(orig_prot))
+ goto retry;
+
+ if (pte_dirty(pte))
+ orig_pte = pte_mkdirty(orig_pte);
+
+ if (pte_young(pte))
+ orig_pte = pte_mkyoung(orig_pte);
+ }
+
+ return orig_pte;
+}
+EXPORT_SYMBOL_GPL(contpte_ptep_get_lockless);
+
+void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned int nr)
+{
+ unsigned long next;
+ unsigned long end;
+ unsigned long pfn;
+ pgprot_t prot;
+
+ /*
+ * The set_ptes() spec guarantees that when nr > 1, the initial state of
+ * all ptes is not-present. Therefore we never need to unfold or
+ * otherwise invalidate a range before we set the new ptes.
+ * contpte_set_ptes() should never be called for nr < 2.
+ */
+ VM_WARN_ON(nr == 1);
+
+ if (!mm_is_user(mm))
+ return __set_ptes(mm, addr, ptep, pte, nr);
+
+ end = addr + (nr << PAGE_SHIFT);
+ pfn = pte_pfn(pte);
+ prot = pte_pgprot(pte);
+
+ do {
+ next = pte_cont_addr_end(addr, end);
+ nr = (next - addr) >> PAGE_SHIFT;
+ pte = pfn_pte(pfn, prot);
+
+ if (((addr | next | (pfn << PAGE_SHIFT)) & ~CONT_PTE_MASK) == 0)
+ pte = pte_mkcont(pte);
+ else
+ pte = pte_mknoncont(pte);
+
+ __set_ptes(mm, addr, ptep, pte, nr);
+
+ addr = next;
+ ptep += nr;
+ pfn += nr;
+
+ } while (addr != end);
+}
+EXPORT_SYMBOL_GPL(contpte_set_ptes);
+
+void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned int nr, int full)
+{
+ contpte_try_unfold_partial(mm, addr, ptep, nr);
+ __clear_full_ptes(mm, addr, ptep, nr, full);
+}
+EXPORT_SYMBOL_GPL(contpte_clear_full_ptes);
+
+pte_t contpte_get_and_clear_full_ptes(struct mm_struct *mm,
+ unsigned long addr, pte_t *ptep,
+ unsigned int nr, int full)
+{
+ contpte_try_unfold_partial(mm, addr, ptep, nr);
+ return __get_and_clear_full_ptes(mm, addr, ptep, nr, full);
+}
+EXPORT_SYMBOL_GPL(contpte_get_and_clear_full_ptes);
+
+int contpte_ptep_test_and_clear_young(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep)
+{
+ /*
+ * ptep_clear_flush_young() technically requires us to clear the access
+ * flag for a _single_ pte. However, the core-mm code actually tracks
+ * access/dirty per folio, not per page. And since we only create a
+ * contig range when the range is covered by a single folio, we can get
+ * away with clearing young for the whole contig range here, so we avoid
+ * having to unfold.
+ */
+
+ int young = 0;
+ int i;
+
+ ptep = contpte_align_down(ptep);
+ addr = ALIGN_DOWN(addr, CONT_PTE_SIZE);
+
+ for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE)
+ young |= __ptep_test_and_clear_young(vma, addr, ptep);
+
+ return young;
+}
+EXPORT_SYMBOL_GPL(contpte_ptep_test_and_clear_young);
+
+int contpte_ptep_clear_flush_young(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep)
+{
+ int young;
+
+ young = contpte_ptep_test_and_clear_young(vma, addr, ptep);
+
+ if (young) {
+ /*
+ * See comment in __ptep_clear_flush_young(); same rationale for
+ * eliding the trailing DSB applies here.
+ */
+ addr = ALIGN_DOWN(addr, CONT_PTE_SIZE);
+ __flush_tlb_range_nosync(vma, addr, addr + CONT_PTE_SIZE,
+ PAGE_SIZE, true, 3);
+ }
+
+ return young;
+}
+EXPORT_SYMBOL_GPL(contpte_ptep_clear_flush_young);
+
+void contpte_wrprotect_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, unsigned int nr)
+{
+ /*
+ * If wrprotecting an entire contig range, we can avoid unfolding. Just
+ * set wrprotect and wait for the later mmu_gather flush to invalidate
+ * the tlb. Until the flush, the page may or may not be wrprotected.
+ * After the flush, it is guaranteed wrprotected. If it's a partial
+ * range though, we must unfold, because we can't have a case where
+ * CONT_PTE is set but wrprotect applies to a subset of the PTEs; this
+ * would cause it to continue to be unpredictable after the flush.
+ */
+
+ contpte_try_unfold_partial(mm, addr, ptep, nr);
+ __wrprotect_ptes(mm, addr, ptep, nr);
+}
+EXPORT_SYMBOL_GPL(contpte_wrprotect_ptes);
+
+int contpte_ptep_set_access_flags(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ pte_t entry, int dirty)
+{
+ unsigned long start_addr;
+ pte_t orig_pte;
+ int i;
+
+ /*
+ * Gather the access/dirty bits for the contiguous range. If nothing has
+ * changed, its a noop.
+ */
+ orig_pte = pte_mknoncont(ptep_get(ptep));
+ if (pte_val(orig_pte) == pte_val(entry))
+ return 0;
+
+ /*
+ * We can fix up access/dirty bits without having to unfold the contig
+ * range. But if the write bit is changing, we must unfold.
+ */
+ if (pte_write(orig_pte) == pte_write(entry)) {
+ /*
+ * For HW access management, we technically only need to update
+ * the flag on a single pte in the range. But for SW access
+ * management, we need to update all the ptes to prevent extra
+ * faults. Avoid per-page tlb flush in __ptep_set_access_flags()
+ * and instead flush the whole range at the end.
+ */
+ ptep = contpte_align_down(ptep);
+ start_addr = addr = ALIGN_DOWN(addr, CONT_PTE_SIZE);
+
+ for (i = 0; i < CONT_PTES; i++, ptep++, addr += PAGE_SIZE)
+ __ptep_set_access_flags(vma, addr, ptep, entry, 0);
+
+ if (dirty)
+ __flush_tlb_range(vma, start_addr, addr,
+ PAGE_SIZE, true, 3);
+ } else {
+ __contpte_try_unfold(vma->vm_mm, addr, ptep, orig_pte);
+ __ptep_set_access_flags(vma, addr, ptep, entry, dirty);
+ }
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(contpte_ptep_set_access_flags);
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 55f6455a8284..8251e2fea9c7 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -191,7 +191,7 @@ static void show_pte(unsigned long addr)
if (!ptep)
break;
- pte = READ_ONCE(*ptep);
+ pte = __ptep_get(ptep);
pr_cont(", pte=%016llx", pte_val(pte));
pte_unmap(ptep);
} while(0);
@@ -205,16 +205,16 @@ static void show_pte(unsigned long addr)
*
* It needs to cope with hardware update of the accessed/dirty state by other
* agents in the system and can safely skip the __sync_icache_dcache() call as,
- * like set_pte_at(), the PTE is never changed from no-exec to exec here.
+ * like __set_ptes(), the PTE is never changed from no-exec to exec here.
*
* Returns whether or not the PTE actually changed.
*/
-int ptep_set_access_flags(struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep,
- pte_t entry, int dirty)
+int __ptep_set_access_flags(struct vm_area_struct *vma,
+ unsigned long address, pte_t *ptep,
+ pte_t entry, int dirty)
{
pteval_t old_pteval, pteval;
- pte_t pte = READ_ONCE(*ptep);
+ pte_t pte = __ptep_get(ptep);
if (pte_same(pte, entry))
return 0;
@@ -257,16 +257,14 @@ static bool is_el1_data_abort(unsigned long esr)
static inline bool is_el1_permission_fault(unsigned long addr, unsigned long esr,
struct pt_regs *regs)
{
- unsigned long fsc_type = esr & ESR_ELx_FSC_TYPE;
-
if (!is_el1_data_abort(esr) && !is_el1_instruction_abort(esr))
return false;
- if (fsc_type == ESR_ELx_FSC_PERM)
+ if (esr_fsc_is_permission_fault(esr))
return true;
if (is_ttbr0_addr(addr) && system_uses_ttbr0_pan())
- return fsc_type == ESR_ELx_FSC_FAULT &&
+ return esr_fsc_is_translation_fault(esr) &&
(regs->pstate & PSR_PAN_BIT);
return false;
@@ -279,8 +277,7 @@ static bool __kprobes is_spurious_el1_translation_fault(unsigned long addr,
unsigned long flags;
u64 par, dfsc;
- if (!is_el1_data_abort(esr) ||
- (esr & ESR_ELx_FSC_TYPE) != ESR_ELx_FSC_FAULT)
+ if (!is_el1_data_abort(esr) || !esr_fsc_is_translation_fault(esr))
return false;
local_irq_save(flags);
@@ -301,7 +298,7 @@ static bool __kprobes is_spurious_el1_translation_fault(unsigned long addr,
* treat the translation fault as spurious.
*/
dfsc = FIELD_GET(SYS_PAR_EL1_FST, par);
- return (dfsc & ESR_ELx_FSC_TYPE) != ESR_ELx_FSC_FAULT;
+ return !esr_fsc_is_translation_fault(dfsc);
}
static void die_kernel_fault(const char *msg, unsigned long addr,
@@ -368,11 +365,6 @@ static bool is_el1_mte_sync_tag_check_fault(unsigned long esr)
return false;
}
-static bool is_translation_fault(unsigned long esr)
-{
- return (esr & ESR_ELx_FSC_TYPE) == ESR_ELx_FSC_FAULT;
-}
-
static void __do_kernel_fault(unsigned long addr, unsigned long esr,
struct pt_regs *regs)
{
@@ -405,7 +397,7 @@ static void __do_kernel_fault(unsigned long addr, unsigned long esr,
} else if (addr < PAGE_SIZE) {
msg = "NULL pointer dereference";
} else {
- if (is_translation_fault(esr) &&
+ if (esr_fsc_is_translation_fault(esr) &&
kfence_handle_page_fault(addr, esr & ESR_ELx_WNR, regs))
return;
@@ -782,18 +774,18 @@ static const struct fault_info fault_info[] = {
{ do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 1 translation fault" },
{ do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 2 translation fault" },
{ do_translation_fault, SIGSEGV, SEGV_MAPERR, "level 3 translation fault" },
- { do_bad, SIGKILL, SI_KERNEL, "unknown 8" },
+ { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 0 access flag fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 1 access flag fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 access flag fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 access flag fault" },
- { do_bad, SIGKILL, SI_KERNEL, "unknown 12" },
+ { do_page_fault, SIGSEGV, SEGV_ACCERR, "level 0 permission fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 1 permission fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 2 permission fault" },
{ do_page_fault, SIGSEGV, SEGV_ACCERR, "level 3 permission fault" },
{ do_sea, SIGBUS, BUS_OBJERR, "synchronous external abort" },
{ do_tag_check_fault, SIGSEGV, SEGV_MTESERR, "synchronous tag check fault" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 18" },
- { do_bad, SIGKILL, SI_KERNEL, "unknown 19" },
+ { do_sea, SIGKILL, SI_KERNEL, "level -1 (translation table walk)" },
{ do_sea, SIGKILL, SI_KERNEL, "level 0 (translation table walk)" },
{ do_sea, SIGKILL, SI_KERNEL, "level 1 (translation table walk)" },
{ do_sea, SIGKILL, SI_KERNEL, "level 2 (translation table walk)" },
@@ -801,7 +793,7 @@ static const struct fault_info fault_info[] = {
{ do_sea, SIGBUS, BUS_OBJERR, "synchronous parity or ECC error" }, // Reserved when RAS is implemented
{ do_bad, SIGKILL, SI_KERNEL, "unknown 25" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 26" },
- { do_bad, SIGKILL, SI_KERNEL, "unknown 27" },
+ { do_sea, SIGKILL, SI_KERNEL, "level -1 synchronous parity error (translation table walk)" }, // Reserved when RAS is implemented
{ do_sea, SIGKILL, SI_KERNEL, "level 0 synchronous parity error (translation table walk)" }, // Reserved when RAS is implemented
{ do_sea, SIGKILL, SI_KERNEL, "level 1 synchronous parity error (translation table walk)" }, // Reserved when RAS is implemented
{ do_sea, SIGKILL, SI_KERNEL, "level 2 synchronous parity error (translation table walk)" }, // Reserved when RAS is implemented
@@ -815,9 +807,9 @@ static const struct fault_info fault_info[] = {
{ do_bad, SIGKILL, SI_KERNEL, "unknown 38" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 39" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 40" },
- { do_bad, SIGKILL, SI_KERNEL, "unknown 41" },
+ { do_bad, SIGKILL, SI_KERNEL, "level -1 address size fault" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 42" },
- { do_bad, SIGKILL, SI_KERNEL, "unknown 43" },
+ { do_translation_fault, SIGSEGV, SEGV_MAPERR, "level -1 translation fault" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 44" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 45" },
{ do_bad, SIGKILL, SI_KERNEL, "unknown 46" },
diff --git a/arch/arm64/mm/fixmap.c b/arch/arm64/mm/fixmap.c
index c0a3301203bd..de1e09d986ad 100644
--- a/arch/arm64/mm/fixmap.c
+++ b/arch/arm64/mm/fixmap.c
@@ -16,6 +16,9 @@
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
+/* ensure that the fixmap region does not grow down into the PCI I/O region */
+static_assert(FIXADDR_TOT_START > PCI_IO_END);
+
#define NR_BM_PTE_TABLES \
SPAN_NR_ENTRIES(FIXADDR_TOT_START, FIXADDR_TOP, PMD_SHIFT)
#define NR_BM_PMD_TABLES \
@@ -101,7 +104,7 @@ void __init early_fixmap_init(void)
unsigned long end = FIXADDR_TOP;
pgd_t *pgdp = pgd_offset_k(addr);
- p4d_t *p4dp = p4d_offset(pgdp, addr);
+ p4d_t *p4dp = p4d_offset_kimg(pgdp, addr);
early_fixmap_init_pud(p4dp, addr, end);
}
@@ -121,9 +124,9 @@ void __set_fixmap(enum fixed_addresses idx,
ptep = fixmap_pte(addr);
if (pgprot_val(flags)) {
- set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags));
+ __set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, flags));
} else {
- pte_clear(&init_mm, addr, ptep);
+ __pte_clear(&init_mm, addr, ptep);
flush_tlb_kernel_range(addr, addr+PAGE_SIZE);
}
}
@@ -167,37 +170,3 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
return dt_virt;
}
-
-/*
- * Copy the fixmap region into a new pgdir.
- */
-void __init fixmap_copy(pgd_t *pgdir)
-{
- if (!READ_ONCE(pgd_val(*pgd_offset_pgd(pgdir, FIXADDR_TOT_START)))) {
- /*
- * The fixmap falls in a separate pgd to the kernel, and doesn't
- * live in the carveout for the swapper_pg_dir. We can simply
- * re-use the existing dir for the fixmap.
- */
- set_pgd(pgd_offset_pgd(pgdir, FIXADDR_TOT_START),
- READ_ONCE(*pgd_offset_k(FIXADDR_TOT_START)));
- } else if (CONFIG_PGTABLE_LEVELS > 3) {
- pgd_t *bm_pgdp;
- p4d_t *bm_p4dp;
- pud_t *bm_pudp;
- /*
- * The fixmap shares its top level pgd entry with the kernel
- * mapping. This can really only occur when we are running
- * with 16k/4 levels, so we can simply reuse the pud level
- * entry instead.
- */
- BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
- bm_pgdp = pgd_offset_pgd(pgdir, FIXADDR_TOT_START);
- bm_p4dp = p4d_offset(bm_pgdp, FIXADDR_TOT_START);
- bm_pudp = pud_set_fixmap_offset(bm_p4dp, FIXADDR_TOT_START);
- pud_populate(&init_mm, bm_pudp, lm_alias(bm_pmd));
- pud_clear_fixmap();
- } else {
- BUG();
- }
-}
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 8116ac599f80..0f0e10bb0a95 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -45,13 +45,6 @@ void __init arm64_hugetlb_cma_reserve(void)
else
order = CONT_PMD_SHIFT - PAGE_SHIFT;
- /*
- * HugeTLB CMA reservation is required for gigantic
- * huge pages which could not be allocated via the
- * page allocator. Just warn if there is any change
- * breaking this assumption.
- */
- WARN_ON(order <= MAX_PAGE_ORDER);
hugetlb_cma_reserve(order);
}
#endif /* CONFIG_CMA */
@@ -152,14 +145,14 @@ pte_t huge_ptep_get(pte_t *ptep)
{
int ncontig, i;
size_t pgsize;
- pte_t orig_pte = ptep_get(ptep);
+ pte_t orig_pte = __ptep_get(ptep);
if (!pte_present(orig_pte) || !pte_cont(orig_pte))
return orig_pte;
ncontig = num_contig_ptes(page_size(pte_page(orig_pte)), &pgsize);
for (i = 0; i < ncontig; i++, ptep++) {
- pte_t pte = ptep_get(ptep);
+ pte_t pte = __ptep_get(ptep);
if (pte_dirty(pte))
orig_pte = pte_mkdirty(orig_pte);
@@ -184,11 +177,11 @@ static pte_t get_clear_contig(struct mm_struct *mm,
unsigned long pgsize,
unsigned long ncontig)
{
- pte_t orig_pte = ptep_get(ptep);
+ pte_t orig_pte = __ptep_get(ptep);
unsigned long i;
for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) {
- pte_t pte = ptep_get_and_clear(mm, addr, ptep);
+ pte_t pte = __ptep_get_and_clear(mm, addr, ptep);
/*
* If HW_AFDBM is enabled, then the HW could turn on
@@ -236,7 +229,7 @@ static void clear_flush(struct mm_struct *mm,
unsigned long i, saddr = addr;
for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
- ptep_clear(mm, addr, ptep);
+ __ptep_get_and_clear(mm, addr, ptep);
flush_tlb_range(&vma, saddr, addr);
}
@@ -254,12 +247,12 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
if (!pte_present(pte)) {
for (i = 0; i < ncontig; i++, ptep++, addr += pgsize)
- set_pte_at(mm, addr, ptep, pte);
+ __set_ptes(mm, addr, ptep, pte, 1);
return;
}
if (!pte_cont(pte)) {
- set_pte_at(mm, addr, ptep, pte);
+ __set_ptes(mm, addr, ptep, pte, 1);
return;
}
@@ -270,7 +263,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
clear_flush(mm, addr, ptep, pgsize, ncontig);
for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
- set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
+ __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1);
}
pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -400,7 +393,7 @@ void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
ncontig = num_contig_ptes(sz, &pgsize);
for (i = 0; i < ncontig; i++, addr += pgsize, ptep++)
- pte_clear(mm, addr, ptep);
+ __pte_clear(mm, addr, ptep);
}
pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
@@ -408,10 +401,10 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
{
int ncontig;
size_t pgsize;
- pte_t orig_pte = ptep_get(ptep);
+ pte_t orig_pte = __ptep_get(ptep);
if (!pte_cont(orig_pte))
- return ptep_get_and_clear(mm, addr, ptep);
+ return __ptep_get_and_clear(mm, addr, ptep);
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
@@ -431,11 +424,11 @@ static int __cont_access_flags_changed(pte_t *ptep, pte_t pte, int ncontig)
{
int i;
- if (pte_write(pte) != pte_write(ptep_get(ptep)))
+ if (pte_write(pte) != pte_write(__ptep_get(ptep)))
return 1;
for (i = 0; i < ncontig; i++) {
- pte_t orig_pte = ptep_get(ptep + i);
+ pte_t orig_pte = __ptep_get(ptep + i);
if (pte_dirty(pte) != pte_dirty(orig_pte))
return 1;
@@ -459,7 +452,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
pte_t orig_pte;
if (!pte_cont(pte))
- return ptep_set_access_flags(vma, addr, ptep, pte, dirty);
+ return __ptep_set_access_flags(vma, addr, ptep, pte, dirty);
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
dpfn = pgsize >> PAGE_SHIFT;
@@ -478,7 +471,7 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma,
hugeprot = pte_pgprot(pte);
for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
- set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
+ __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1);
return 1;
}
@@ -492,8 +485,8 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm,
size_t pgsize;
pte_t pte;
- if (!pte_cont(READ_ONCE(*ptep))) {
- ptep_set_wrprotect(mm, addr, ptep);
+ if (!pte_cont(__ptep_get(ptep))) {
+ __ptep_set_wrprotect(mm, addr, ptep);
return;
}
@@ -507,7 +500,7 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm,
pfn = pte_pfn(pte);
for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn)
- set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot));
+ __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1);
}
pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
@@ -517,7 +510,7 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
size_t pgsize;
int ncontig;
- if (!pte_cont(READ_ONCE(*ptep)))
+ if (!pte_cont(__ptep_get(ptep)))
return ptep_clear_flush(vma, addr, ptep);
ncontig = find_num_contig(mm, addr, ptep, &pgsize);
@@ -550,7 +543,7 @@ pte_t huge_ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr
* when the permission changes from executable to non-executable
* in cases where cpu is affected with errata #2645198.
*/
- if (pte_user_exec(READ_ONCE(*ptep)))
+ if (pte_user_exec(__ptep_get(ptep)))
return huge_ptep_clear_flush(vma, addr, ptep);
}
return huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 74c1db8ce271..03efd86dce0a 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -100,7 +100,7 @@ static void __init arch_reserve_crashkernel(void)
bool high = false;
int ret;
- if (!IS_ENABLED(CONFIG_KEXEC_CORE))
+ if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
return;
ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
@@ -238,7 +238,7 @@ void __init arm64_memblock_init(void)
* physical address of PAGE_OFFSET, we have to *subtract* from it.
*/
if (IS_ENABLED(CONFIG_ARM64_VA_BITS_52) && (vabits_actual != 52))
- memstart_addr -= _PAGE_OFFSET(48) - _PAGE_OFFSET(52);
+ memstart_addr -= _PAGE_OFFSET(vabits_actual) - _PAGE_OFFSET(52);
/*
* Apply the memory limit if it was set. Since the kernel may be loaded
diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index 4c7ad574b946..b65a29440a0c 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -23,7 +23,7 @@
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
-static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE);
+static pgd_t tmp_pg_dir[PTRS_PER_PTE] __initdata __aligned(PAGE_SIZE);
/*
* The p*d_populate functions call virt_to_phys implicitly so they can't be used
@@ -99,6 +99,19 @@ static pud_t *__init kasan_pud_offset(p4d_t *p4dp, unsigned long addr, int node,
return early ? pud_offset_kimg(p4dp, addr) : pud_offset(p4dp, addr);
}
+static p4d_t *__init kasan_p4d_offset(pgd_t *pgdp, unsigned long addr, int node,
+ bool early)
+{
+ if (pgd_none(READ_ONCE(*pgdp))) {
+ phys_addr_t p4d_phys = early ?
+ __pa_symbol(kasan_early_shadow_p4d)
+ : kasan_alloc_zeroed_page(node);
+ __pgd_populate(pgdp, p4d_phys, PGD_TYPE_TABLE);
+ }
+
+ return early ? p4d_offset_kimg(pgdp, addr) : p4d_offset(pgdp, addr);
+}
+
static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr,
unsigned long end, int node, bool early)
{
@@ -112,8 +125,8 @@ static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr,
if (!early)
memset(__va(page_phys), KASAN_SHADOW_INIT, PAGE_SIZE);
next = addr + PAGE_SIZE;
- set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL));
- } while (ptep++, addr = next, addr != end && pte_none(READ_ONCE(*ptep)));
+ __set_pte(ptep, pfn_pte(__phys_to_pfn(page_phys), PAGE_KERNEL));
+ } while (ptep++, addr = next, addr != end && pte_none(__ptep_get(ptep)));
}
static void __init kasan_pmd_populate(pud_t *pudp, unsigned long addr,
@@ -144,12 +157,12 @@ static void __init kasan_p4d_populate(pgd_t *pgdp, unsigned long addr,
unsigned long end, int node, bool early)
{
unsigned long next;
- p4d_t *p4dp = p4d_offset(pgdp, addr);
+ p4d_t *p4dp = kasan_p4d_offset(pgdp, addr, node, early);
do {
next = p4d_addr_end(addr, end);
kasan_pud_populate(p4dp, addr, next, node, early);
- } while (p4dp++, addr = next, addr != end);
+ } while (p4dp++, addr = next, addr != end && p4d_none(READ_ONCE(*p4dp)));
}
static void __init kasan_pgd_populate(unsigned long addr, unsigned long end,
@@ -165,19 +178,48 @@ static void __init kasan_pgd_populate(unsigned long addr, unsigned long end,
} while (pgdp++, addr = next, addr != end);
}
+#if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS > 4
+#define SHADOW_ALIGN P4D_SIZE
+#else
+#define SHADOW_ALIGN PUD_SIZE
+#endif
+
+/*
+ * Return whether 'addr' is aligned to the size covered by a root level
+ * descriptor.
+ */
+static bool __init root_level_aligned(u64 addr)
+{
+ int shift = (ARM64_HW_PGTABLE_LEVELS(vabits_actual) - 1) * (PAGE_SHIFT - 3);
+
+ return (addr % (PAGE_SIZE << shift)) == 0;
+}
+
/* The early shadow maps everything to a single page of zeroes */
asmlinkage void __init kasan_early_init(void)
{
BUILD_BUG_ON(KASAN_SHADOW_OFFSET !=
KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT)));
- /*
- * We cannot check the actual value of KASAN_SHADOW_START during build,
- * as it depends on vabits_actual. As a best-effort approach, check
- * potential values calculated based on VA_BITS and VA_BITS_MIN.
- */
- BUILD_BUG_ON(!IS_ALIGNED(_KASAN_SHADOW_START(VA_BITS), PGDIR_SIZE));
- BUILD_BUG_ON(!IS_ALIGNED(_KASAN_SHADOW_START(VA_BITS_MIN), PGDIR_SIZE));
- BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE));
+ BUILD_BUG_ON(!IS_ALIGNED(_KASAN_SHADOW_START(VA_BITS), SHADOW_ALIGN));
+ BUILD_BUG_ON(!IS_ALIGNED(_KASAN_SHADOW_START(VA_BITS_MIN), SHADOW_ALIGN));
+ BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, SHADOW_ALIGN));
+
+ if (!root_level_aligned(KASAN_SHADOW_START)) {
+ /*
+ * The start address is misaligned, and so the next level table
+ * will be shared with the linear region. This can happen with
+ * 4 or 5 level paging, so install a generic pte_t[] as the
+ * next level. This prevents the kasan_pgd_populate call below
+ * from inserting an entry that refers to the shared KASAN zero
+ * shadow pud_t[]/p4d_t[], which could end up getting corrupted
+ * when the linear region is mapped.
+ */
+ static pte_t tbl[PTRS_PER_PTE] __page_aligned_bss;
+ pgd_t *pgdp = pgd_offset_k(KASAN_SHADOW_START);
+
+ set_pgd(pgdp, __pgd(__pa_symbol(tbl) | PGD_TYPE_TABLE));
+ }
+
kasan_pgd_populate(KASAN_SHADOW_START, KASAN_SHADOW_END, NUMA_NO_NODE,
true);
}
@@ -190,34 +232,74 @@ static void __init kasan_map_populate(unsigned long start, unsigned long end,
}
/*
- * Copy the current shadow region into a new pgdir.
+ * Return the descriptor index of 'addr' in the root level table
*/
-void __init kasan_copy_shadow(pgd_t *pgdir)
+static int __init root_level_idx(u64 addr)
{
- pgd_t *pgdp, *pgdp_new, *pgdp_end;
+ /*
+ * On 64k pages, the TTBR1 range root tables are extended for 52-bit
+ * virtual addressing, and TTBR1 will simply point to the pgd_t entry
+ * that covers the start of the 48-bit addressable VA space if LVA is
+ * not implemented. This means we need to index the table as usual,
+ * instead of masking off bits based on vabits_actual.
+ */
+ u64 vabits = IS_ENABLED(CONFIG_ARM64_64K_PAGES) ? VA_BITS
+ : vabits_actual;
+ int shift = (ARM64_HW_PGTABLE_LEVELS(vabits) - 1) * (PAGE_SHIFT - 3);
- pgdp = pgd_offset_k(KASAN_SHADOW_START);
- pgdp_end = pgd_offset_k(KASAN_SHADOW_END);
- pgdp_new = pgd_offset_pgd(pgdir, KASAN_SHADOW_START);
- do {
- set_pgd(pgdp_new, READ_ONCE(*pgdp));
- } while (pgdp++, pgdp_new++, pgdp != pgdp_end);
+ return (addr & ~_PAGE_OFFSET(vabits)) >> (shift + PAGE_SHIFT);
+}
+
+/*
+ * Clone a next level table from swapper_pg_dir into tmp_pg_dir
+ */
+static void __init clone_next_level(u64 addr, pgd_t *tmp_pg_dir, pud_t *pud)
+{
+ int idx = root_level_idx(addr);
+ pgd_t pgd = READ_ONCE(swapper_pg_dir[idx]);
+ pud_t *pudp = (pud_t *)__phys_to_kimg(__pgd_to_phys(pgd));
+
+ memcpy(pud, pudp, PAGE_SIZE);
+ tmp_pg_dir[idx] = __pgd(__phys_to_pgd_val(__pa_symbol(pud)) |
+ PUD_TYPE_TABLE);
}
-static void __init clear_pgds(unsigned long start,
- unsigned long end)
+/*
+ * Return the descriptor index of 'addr' in the next level table
+ */
+static int __init next_level_idx(u64 addr)
{
- /*
- * Remove references to kasan page tables from
- * swapper_pg_dir. pgd_clear() can't be used
- * here because it's nop on 2,3-level pagetable setups
- */
- for (; start < end; start += PGDIR_SIZE)
- set_pgd(pgd_offset_k(start), __pgd(0));
+ int shift = (ARM64_HW_PGTABLE_LEVELS(vabits_actual) - 2) * (PAGE_SHIFT - 3);
+
+ return (addr >> (shift + PAGE_SHIFT)) % PTRS_PER_PTE;
+}
+
+/*
+ * Dereference the table descriptor at 'pgd_idx' and clear the entries from
+ * 'start' to 'end' (exclusive) from the table.
+ */
+static void __init clear_next_level(int pgd_idx, int start, int end)
+{
+ pgd_t pgd = READ_ONCE(swapper_pg_dir[pgd_idx]);
+ pud_t *pudp = (pud_t *)__phys_to_kimg(__pgd_to_phys(pgd));
+
+ memset(&pudp[start], 0, (end - start) * sizeof(pud_t));
+}
+
+static void __init clear_shadow(u64 start, u64 end)
+{
+ int l = root_level_idx(start), m = root_level_idx(end);
+
+ if (!root_level_aligned(start))
+ clear_next_level(l++, next_level_idx(start), PTRS_PER_PTE);
+ if (!root_level_aligned(end))
+ clear_next_level(m, 0, next_level_idx(end));
+ memset(&swapper_pg_dir[l], 0, (m - l) * sizeof(pgd_t));
}
static void __init kasan_init_shadow(void)
{
+ static pud_t pud[2][PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
u64 kimg_shadow_start, kimg_shadow_end;
u64 mod_shadow_start;
u64 vmalloc_shadow_end;
@@ -239,10 +321,23 @@ static void __init kasan_init_shadow(void)
* setup will be finished.
*/
memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(tmp_pg_dir));
+
+ /*
+ * If the start or end address of the shadow region is not aligned to
+ * the root level size, we have to allocate a temporary next-level table
+ * in each case, clone the next level of descriptors, and install the
+ * table into tmp_pg_dir. Note that with 5 levels of paging, the next
+ * level will in fact be p4d_t, but that makes no difference in this
+ * case.
+ */
+ if (!root_level_aligned(KASAN_SHADOW_START))
+ clone_next_level(KASAN_SHADOW_START, tmp_pg_dir, pud[0]);
+ if (!root_level_aligned(KASAN_SHADOW_END))
+ clone_next_level(KASAN_SHADOW_END, tmp_pg_dir, pud[1]);
dsb(ishst);
- cpu_replace_ttbr1(lm_alias(tmp_pg_dir), idmap_pg_dir);
+ cpu_replace_ttbr1(lm_alias(tmp_pg_dir));
- clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
+ clear_shadow(KASAN_SHADOW_START, KASAN_SHADOW_END);
kasan_map_populate(kimg_shadow_start, kimg_shadow_end,
early_pfn_to_nid(virt_to_pfn(lm_alias(KERNEL_START))));
@@ -271,12 +366,12 @@ static void __init kasan_init_shadow(void)
* so we should make sure that it maps the zero page read-only.
*/
for (i = 0; i < PTRS_PER_PTE; i++)
- set_pte(&kasan_early_shadow_pte[i],
+ __set_pte(&kasan_early_shadow_pte[i],
pfn_pte(sym_to_pfn(kasan_early_shadow_page),
PAGE_KERNEL_RO));
memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE);
- cpu_replace_ttbr1(lm_alias(swapper_pg_dir), idmap_pg_dir);
+ cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
}
static void __init kasan_init_depth(void)
diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
index 645fe60d000f..642bdf908b22 100644
--- a/arch/arm64/mm/mmap.c
+++ b/arch/arm64/mm/mmap.c
@@ -73,6 +73,10 @@ static int __init adjust_protection_map(void)
protection_map[VM_EXEC | VM_SHARED] = PAGE_EXECONLY;
}
+ if (lpa2_is_enabled())
+ for (int i = 0; i < ARRAY_SIZE(protection_map); i++)
+ pgprot_val(protection_map[i]) &= ~PTE_SHARED;
+
return 0;
}
arch_initcall(adjust_protection_map);
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 1ac7467d34c9..495b732d5af3 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -45,18 +45,13 @@
#define NO_CONT_MAPPINGS BIT(1)
#define NO_EXEC_MAPPINGS BIT(2) /* assumes FEAT_HPDS is not used */
-int idmap_t0sz __ro_after_init;
-
-#if VA_BITS > 48
-u64 vabits_actual __ro_after_init = VA_BITS_MIN;
-EXPORT_SYMBOL(vabits_actual);
-#endif
-
u64 kimage_voffset __ro_after_init;
EXPORT_SYMBOL(kimage_voffset);
u32 __boot_cpu_mode[] = { BOOT_CPU_MODE_EL2, BOOT_CPU_MODE_EL1 };
+static bool rodata_is_rw __ro_after_init = true;
+
/*
* The booting CPU updates the failed status @__early_cpu_boot_status,
* with MMU turned off.
@@ -73,10 +68,21 @@ EXPORT_SYMBOL(empty_zero_page);
static DEFINE_SPINLOCK(swapper_pgdir_lock);
static DEFINE_MUTEX(fixmap_lock);
-void set_swapper_pgd(pgd_t *pgdp, pgd_t pgd)
+void noinstr set_swapper_pgd(pgd_t *pgdp, pgd_t pgd)
{
pgd_t *fixmap_pgdp;
+ /*
+ * Don't bother with the fixmap if swapper_pg_dir is still mapped
+ * writable in the kernel mapping.
+ */
+ if (rodata_is_rw) {
+ WRITE_ONCE(*pgdp, pgd);
+ dsb(ishst);
+ isb();
+ return;
+ }
+
spin_lock(&swapper_pgdir_lock);
fixmap_pgdp = pgd_set_fixmap(__pa_symbol(pgdp));
WRITE_ONCE(*fixmap_pgdp, pgd);
@@ -173,16 +179,16 @@ static void init_pte(pmd_t *pmdp, unsigned long addr, unsigned long end,
ptep = pte_set_fixmap_offset(pmdp, addr);
do {
- pte_t old_pte = READ_ONCE(*ptep);
+ pte_t old_pte = __ptep_get(ptep);
- set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot));
+ __set_pte(ptep, pfn_pte(__phys_to_pfn(phys), prot));
/*
* After the PTE entry has been populated once, we
* only allow updates to the permission attributes.
*/
BUG_ON(!pgattr_change_is_safe(pte_val(old_pte),
- READ_ONCE(pte_val(*ptep))));
+ pte_val(__ptep_get(ptep))));
phys += PAGE_SIZE;
} while (ptep++, addr += PAGE_SIZE, addr != end);
@@ -307,15 +313,14 @@ static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr,
} while (addr = next, addr != end);
}
-static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end,
+static void alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end,
phys_addr_t phys, pgprot_t prot,
phys_addr_t (*pgtable_alloc)(int),
int flags)
{
unsigned long next;
- pud_t *pudp;
- p4d_t *p4dp = p4d_offset(pgdp, addr);
p4d_t p4d = READ_ONCE(*p4dp);
+ pud_t *pudp;
if (p4d_none(p4d)) {
p4dval_t p4dval = P4D_TYPE_TABLE | P4D_TABLE_UXN;
@@ -363,6 +368,46 @@ static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end,
pud_clear_fixmap();
}
+static void alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end,
+ phys_addr_t phys, pgprot_t prot,
+ phys_addr_t (*pgtable_alloc)(int),
+ int flags)
+{
+ unsigned long next;
+ pgd_t pgd = READ_ONCE(*pgdp);
+ p4d_t *p4dp;
+
+ if (pgd_none(pgd)) {
+ pgdval_t pgdval = PGD_TYPE_TABLE | PGD_TABLE_UXN;
+ phys_addr_t p4d_phys;
+
+ if (flags & NO_EXEC_MAPPINGS)
+ pgdval |= PGD_TABLE_PXN;
+ BUG_ON(!pgtable_alloc);
+ p4d_phys = pgtable_alloc(P4D_SHIFT);
+ __pgd_populate(pgdp, p4d_phys, pgdval);
+ pgd = READ_ONCE(*pgdp);
+ }
+ BUG_ON(pgd_bad(pgd));
+
+ p4dp = p4d_set_fixmap_offset(pgdp, addr);
+ do {
+ p4d_t old_p4d = READ_ONCE(*p4dp);
+
+ next = p4d_addr_end(addr, end);
+
+ alloc_init_pud(p4dp, addr, next, phys, prot,
+ pgtable_alloc, flags);
+
+ BUG_ON(p4d_val(old_p4d) != 0 &&
+ p4d_val(old_p4d) != READ_ONCE(p4d_val(*p4dp)));
+
+ phys += next - addr;
+ } while (p4dp++, addr = next, addr != end);
+
+ p4d_clear_fixmap();
+}
+
static void __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys,
unsigned long virt, phys_addr_t size,
pgprot_t prot,
@@ -385,7 +430,7 @@ static void __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys,
do {
next = pgd_addr_end(addr, end);
- alloc_init_pud(pgdp, addr, next, phys, prot, pgtable_alloc,
+ alloc_init_p4d(pgdp, addr, next, phys, prot, pgtable_alloc,
flags);
phys += next - addr;
} while (pgdp++, addr = next, addr != end);
@@ -576,8 +621,12 @@ static void __init map_mem(pgd_t *pgdp)
* entries at any level are being shared between the linear region and
* the vmalloc region. Check whether this is true for the PGD level, in
* which case it is guaranteed to be true for all other levels as well.
+ * (Unless we are running with support for LPA2, in which case the
+ * entire reduced VA space is covered by a single pgd_t which will have
+ * been populated without the PXNTable attribute by the time we get here.)
*/
- BUILD_BUG_ON(pgd_index(direct_map_end - 1) == pgd_index(direct_map_end));
+ BUILD_BUG_ON(pgd_index(direct_map_end - 1) == pgd_index(direct_map_end) &&
+ pgd_index(_PAGE_OFFSET(VA_BITS_MIN)) != PTRS_PER_PGD - 1);
early_kfence_pool = arm64_kfence_alloc_pool();
@@ -630,15 +679,14 @@ void mark_rodata_ro(void)
* to cover NOTES and EXCEPTION_TABLE.
*/
section_size = (unsigned long)__init_begin - (unsigned long)__start_rodata;
+ WRITE_ONCE(rodata_is_rw, false);
update_mapping_prot(__pa_symbol(__start_rodata), (unsigned long)__start_rodata,
section_size, PAGE_KERNEL_RO);
-
- debug_checkwx();
}
-static void __init map_kernel_segment(pgd_t *pgdp, void *va_start, void *va_end,
- pgprot_t prot, struct vm_struct *vma,
- int flags, unsigned long vm_flags)
+static void __init declare_vma(struct vm_struct *vma,
+ void *va_start, void *va_end,
+ unsigned long vm_flags)
{
phys_addr_t pa_start = __pa_symbol(va_start);
unsigned long size = va_end - va_start;
@@ -646,9 +694,6 @@ static void __init map_kernel_segment(pgd_t *pgdp, void *va_start, void *va_end,
BUG_ON(!PAGE_ALIGNED(pa_start));
BUG_ON(!PAGE_ALIGNED(size));
- __create_pgd_mapping(pgdp, pa_start, (unsigned long)va_start, size, prot,
- early_pgtable_alloc, flags);
-
if (!(vm_flags & VM_NO_GUARD))
size += PAGE_SIZE;
@@ -661,12 +706,12 @@ static void __init map_kernel_segment(pgd_t *pgdp, void *va_start, void *va_end,
vm_area_add_early(vma);
}
+#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
static pgprot_t kernel_exec_prot(void)
{
return rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
}
-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
static int __init map_entry_trampoline(void)
{
int i;
@@ -701,80 +746,36 @@ core_initcall(map_entry_trampoline);
#endif
/*
- * Open coded check for BTI, only for use to determine configuration
- * for early mappings for before the cpufeature code has run.
+ * Declare the VMA areas for the kernel
*/
-static bool arm64_early_this_cpu_has_bti(void)
+static void __init declare_kernel_vmas(void)
{
- u64 pfr1;
-
- if (!IS_ENABLED(CONFIG_ARM64_BTI_KERNEL))
- return false;
+ static struct vm_struct vmlinux_seg[KERNEL_SEGMENT_COUNT];
- pfr1 = __read_sysreg_by_encoding(SYS_ID_AA64PFR1_EL1);
- return cpuid_feature_extract_unsigned_field(pfr1,
- ID_AA64PFR1_EL1_BT_SHIFT);
+ declare_vma(&vmlinux_seg[0], _stext, _etext, VM_NO_GUARD);
+ declare_vma(&vmlinux_seg[1], __start_rodata, __inittext_begin, VM_NO_GUARD);
+ declare_vma(&vmlinux_seg[2], __inittext_begin, __inittext_end, VM_NO_GUARD);
+ declare_vma(&vmlinux_seg[3], __initdata_begin, __initdata_end, VM_NO_GUARD);
+ declare_vma(&vmlinux_seg[4], _data, _end, 0);
}
-/*
- * Create fine-grained mappings for the kernel.
- */
-static void __init map_kernel(pgd_t *pgdp)
-{
- static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_inittext,
- vmlinux_initdata, vmlinux_data;
-
- /*
- * External debuggers may need to write directly to the text
- * mapping to install SW breakpoints. Allow this (only) when
- * explicitly requested with rodata=off.
- */
- pgprot_t text_prot = kernel_exec_prot();
-
- /*
- * If we have a CPU that supports BTI and a kernel built for
- * BTI then mark the kernel executable text as guarded pages
- * now so we don't have to rewrite the page tables later.
- */
- if (arm64_early_this_cpu_has_bti())
- text_prot = __pgprot_modify(text_prot, PTE_GP, PTE_GP);
-
- /*
- * Only rodata will be remapped with different permissions later on,
- * all other segments are allowed to use contiguous mappings.
- */
- map_kernel_segment(pgdp, _stext, _etext, text_prot, &vmlinux_text, 0,
- VM_NO_GUARD);
- map_kernel_segment(pgdp, __start_rodata, __inittext_begin, PAGE_KERNEL,
- &vmlinux_rodata, NO_CONT_MAPPINGS, VM_NO_GUARD);
- map_kernel_segment(pgdp, __inittext_begin, __inittext_end, text_prot,
- &vmlinux_inittext, 0, VM_NO_GUARD);
- map_kernel_segment(pgdp, __initdata_begin, __initdata_end, PAGE_KERNEL,
- &vmlinux_initdata, 0, VM_NO_GUARD);
- map_kernel_segment(pgdp, _data, _end, PAGE_KERNEL, &vmlinux_data, 0, 0);
+void __pi_map_range(u64 *pgd, u64 start, u64 end, u64 pa, pgprot_t prot,
+ int level, pte_t *tbl, bool may_use_cont, u64 va_offset);
- fixmap_copy(pgdp);
- kasan_copy_shadow(pgdp);
-}
+static u8 idmap_ptes[IDMAP_LEVELS - 1][PAGE_SIZE] __aligned(PAGE_SIZE) __ro_after_init,
+ kpti_ptes[IDMAP_LEVELS - 1][PAGE_SIZE] __aligned(PAGE_SIZE) __ro_after_init;
static void __init create_idmap(void)
{
u64 start = __pa_symbol(__idmap_text_start);
- u64 size = __pa_symbol(__idmap_text_end) - start;
- pgd_t *pgd = idmap_pg_dir;
- u64 pgd_phys;
-
- /* check if we need an additional level of translation */
- if (VA_BITS < 48 && idmap_t0sz < (64 - VA_BITS_MIN)) {
- pgd_phys = early_pgtable_alloc(PAGE_SHIFT);
- set_pgd(&idmap_pg_dir[start >> VA_BITS],
- __pgd(pgd_phys | P4D_TYPE_TABLE));
- pgd = __va(pgd_phys);
- }
- __create_pgd_mapping(pgd, start, start, size, PAGE_KERNEL_ROX,
- early_pgtable_alloc, 0);
+ u64 end = __pa_symbol(__idmap_text_end);
+ u64 ptep = __pa_symbol(idmap_ptes);
- if (IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0)) {
+ __pi_map_range(&ptep, start, end, start, PAGE_KERNEL_ROX,
+ IDMAP_ROOT_LEVEL, (pte_t *)idmap_pg_dir, false,
+ __phys_to_virt(ptep) - ptep);
+
+ if (IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0) && !arm64_use_ng_mappings) {
extern u32 __idmap_kpti_flag;
u64 pa = __pa_symbol(&__idmap_kpti_flag);
@@ -782,32 +783,21 @@ static void __init create_idmap(void)
* The KPTI G-to-nG conversion code needs a read-write mapping
* of its synchronization flag in the ID map.
*/
- __create_pgd_mapping(pgd, pa, pa, sizeof(u32), PAGE_KERNEL,
- early_pgtable_alloc, 0);
+ ptep = __pa_symbol(kpti_ptes);
+ __pi_map_range(&ptep, pa, pa + sizeof(u32), pa, PAGE_KERNEL,
+ IDMAP_ROOT_LEVEL, (pte_t *)idmap_pg_dir, false,
+ __phys_to_virt(ptep) - ptep);
}
}
void __init paging_init(void)
{
- pgd_t *pgdp = pgd_set_fixmap(__pa_symbol(swapper_pg_dir));
- extern pgd_t init_idmap_pg_dir[];
-
- idmap_t0sz = 63UL - __fls(__pa_symbol(_end) | GENMASK(VA_BITS_MIN - 1, 0));
-
- map_kernel(pgdp);
- map_mem(pgdp);
-
- pgd_clear_fixmap();
-
- cpu_replace_ttbr1(lm_alias(swapper_pg_dir), init_idmap_pg_dir);
- init_mm.pgd = swapper_pg_dir;
-
- memblock_phys_free(__pa_symbol(init_pg_dir),
- __pa_symbol(init_pg_end) - __pa_symbol(init_pg_dir));
+ map_mem(swapper_pg_dir);
memblock_allow_resize();
create_idmap();
+ declare_kernel_vmas();
}
#ifdef CONFIG_MEMORY_HOTPLUG
@@ -854,12 +844,12 @@ static void unmap_hotplug_pte_range(pmd_t *pmdp, unsigned long addr,
do {
ptep = pte_offset_kernel(pmdp, addr);
- pte = READ_ONCE(*ptep);
+ pte = __ptep_get(ptep);
if (pte_none(pte))
continue;
WARN_ON(!pte_present(pte));
- pte_clear(&init_mm, addr, ptep);
+ __pte_clear(&init_mm, addr, ptep);
flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
if (free_mapped)
free_hotplug_page_range(pte_page(pte),
@@ -987,7 +977,7 @@ static void free_empty_pte_table(pmd_t *pmdp, unsigned long addr,
do {
ptep = pte_offset_kernel(pmdp, addr);
- pte = READ_ONCE(*ptep);
+ pte = __ptep_get(ptep);
/*
* This is just a sanity check here which verifies that
@@ -1006,7 +996,7 @@ static void free_empty_pte_table(pmd_t *pmdp, unsigned long addr,
*/
ptep = pte_offset_kernel(pmdp, 0UL);
for (i = 0; i < PTRS_PER_PTE; i++) {
- if (!pte_none(READ_ONCE(ptep[i])))
+ if (!pte_none(__ptep_get(&ptep[i])))
return;
}
@@ -1073,10 +1063,10 @@ static void free_empty_pud_table(p4d_t *p4dp, unsigned long addr,
free_empty_pmd_table(pudp, addr, next, floor, ceiling);
} while (addr = next, addr < end);
- if (CONFIG_PGTABLE_LEVELS <= 3)
+ if (!pgtable_l4_enabled())
return;
- if (!pgtable_range_aligned(start, end, floor, ceiling, PGDIR_MASK))
+ if (!pgtable_range_aligned(start, end, floor, ceiling, P4D_MASK))
return;
/*
@@ -1099,8 +1089,8 @@ static void free_empty_p4d_table(pgd_t *pgdp, unsigned long addr,
unsigned long end, unsigned long floor,
unsigned long ceiling)
{
- unsigned long next;
p4d_t *p4dp, p4d;
+ unsigned long i, next, start = addr;
do {
next = p4d_addr_end(addr, end);
@@ -1112,6 +1102,27 @@ static void free_empty_p4d_table(pgd_t *pgdp, unsigned long addr,
WARN_ON(!p4d_present(p4d));
free_empty_pud_table(p4dp, addr, next, floor, ceiling);
} while (addr = next, addr < end);
+
+ if (!pgtable_l5_enabled())
+ return;
+
+ if (!pgtable_range_aligned(start, end, floor, ceiling, PGDIR_MASK))
+ return;
+
+ /*
+ * Check whether we can free the p4d page if the rest of the
+ * entries are empty. Overlap with other regions have been
+ * handled by the floor/ceiling check.
+ */
+ p4dp = p4d_offset(pgdp, 0UL);
+ for (i = 0; i < PTRS_PER_P4D; i++) {
+ if (!p4d_none(READ_ONCE(p4dp[i])))
+ return;
+ }
+
+ pgd_clear(pgdp);
+ __flush_tlb_kernel_pgtable(start);
+ free_hotplug_pgtable_page(virt_to_page(p4dp));
}
static void free_empty_tables(unsigned long addr, unsigned long end,
@@ -1196,6 +1207,12 @@ int pmd_set_huge(pmd_t *pmdp, phys_addr_t phys, pgprot_t prot)
return 1;
}
+#ifndef __PAGETABLE_P4D_FOLDED
+void p4d_clear_huge(p4d_t *p4dp)
+{
+}
+#endif
+
int pud_clear_huge(pud_t *pudp)
{
if (!pud_sect(READ_ONCE(*pudp)))
@@ -1475,7 +1492,7 @@ pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, pte
* when the permission changes from executable to non-executable
* in cases where cpu is affected with errata #2645198.
*/
- if (pte_user_exec(READ_ONCE(*ptep)))
+ if (pte_user_exec(ptep_get(ptep)))
return ptep_clear_flush(vma, addr, ptep);
}
return ptep_get_and_clear(vma->vm_mm, addr, ptep);
@@ -1486,3 +1503,35 @@ void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, pte
{
set_pte_at(vma->vm_mm, addr, ptep, pte);
}
+
+/*
+ * Atomically replaces the active TTBR1_EL1 PGD with a new VA-compatible PGD,
+ * avoiding the possibility of conflicting TLB entries being allocated.
+ */
+void __cpu_replace_ttbr1(pgd_t *pgdp, bool cnp)
+{
+ typedef void (ttbr_replace_func)(phys_addr_t);
+ extern ttbr_replace_func idmap_cpu_replace_ttbr1;
+ ttbr_replace_func *replace_phys;
+ unsigned long daif;
+
+ /* phys_to_ttbr() zeros lower 2 bits of ttbr with 52-bit PA */
+ phys_addr_t ttbr1 = phys_to_ttbr(virt_to_phys(pgdp));
+
+ if (cnp)
+ ttbr1 |= TTBR_CNP_BIT;
+
+ replace_phys = (void *)__pa_symbol(idmap_cpu_replace_ttbr1);
+
+ cpu_install_idmap();
+
+ /*
+ * We really don't want to take *any* exceptions while TTBR1 is
+ * in the process of being replaced so mask everything.
+ */
+ daif = local_daif_save();
+ replace_phys(ttbr1);
+ local_daif_restore(daif);
+
+ cpu_uninstall_idmap();
+}
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 924843f1f661..0c4e3ecf989d 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -36,12 +36,12 @@ bool can_set_direct_map(void)
static int change_page_range(pte_t *ptep, unsigned long addr, void *data)
{
struct page_change_data *cdata = data;
- pte_t pte = READ_ONCE(*ptep);
+ pte_t pte = __ptep_get(ptep);
pte = clear_pte_bit(pte, cdata->clear_mask);
pte = set_pte_bit(pte, cdata->set_mask);
- set_pte(ptep, pte);
+ __set_pte(ptep, pte);
return 0;
}
@@ -245,5 +245,5 @@ bool kernel_page_present(struct page *page)
return true;
ptep = pte_offset_kernel(pmdp, addr);
- return pte_valid(READ_ONCE(*ptep));
+ return pte_valid(__ptep_get(ptep));
}
diff --git a/arch/arm64/mm/pgd.c b/arch/arm64/mm/pgd.c
index 4a64089e5771..0c501cabc238 100644
--- a/arch/arm64/mm/pgd.c
+++ b/arch/arm64/mm/pgd.c
@@ -17,11 +17,22 @@
static struct kmem_cache *pgd_cache __ro_after_init;
+static bool pgdir_is_page_size(void)
+{
+ if (PGD_SIZE == PAGE_SIZE)
+ return true;
+ if (CONFIG_PGTABLE_LEVELS == 4)
+ return !pgtable_l4_enabled();
+ if (CONFIG_PGTABLE_LEVELS == 5)
+ return !pgtable_l5_enabled();
+ return false;
+}
+
pgd_t *pgd_alloc(struct mm_struct *mm)
{
gfp_t gfp = GFP_PGTABLE_USER;
- if (PGD_SIZE == PAGE_SIZE)
+ if (pgdir_is_page_size())
return (pgd_t *)__get_free_page(gfp);
else
return kmem_cache_alloc(pgd_cache, gfp);
@@ -29,7 +40,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
- if (PGD_SIZE == PAGE_SIZE)
+ if (pgdir_is_page_size())
free_page((unsigned long)pgd);
else
kmem_cache_free(pgd_cache, pgd);
@@ -37,7 +48,7 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd)
void __init pgtable_cache_init(void)
{
- if (PGD_SIZE == PAGE_SIZE)
+ if (pgdir_is_page_size())
return;
#ifdef CONFIG_ARM64_PA_BITS_52
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index f66c37a1610e..9d40f3ffd8d2 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -195,27 +195,36 @@ SYM_TYPED_FUNC_START(idmap_cpu_replace_ttbr1)
ret
SYM_FUNC_END(idmap_cpu_replace_ttbr1)
+SYM_FUNC_ALIAS(__pi_idmap_cpu_replace_ttbr1, idmap_cpu_replace_ttbr1)
.popsection
#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
-#define KPTI_NG_PTE_FLAGS (PTE_ATTRINDX(MT_NORMAL) | SWAPPER_PTE_FLAGS | PTE_WRITE)
+#define KPTI_NG_PTE_FLAGS (PTE_ATTRINDX(MT_NORMAL) | PTE_TYPE_PAGE | \
+ PTE_AF | PTE_SHARED | PTE_UXN | PTE_WRITE)
.pushsection ".idmap.text", "a"
+ .macro pte_to_phys, phys, pte
+ and \phys, \pte, #PTE_ADDR_LOW
+#ifdef CONFIG_ARM64_PA_BITS_52
+ and \pte, \pte, #PTE_ADDR_HIGH
+ orr \phys, \phys, \pte, lsl #PTE_ADDR_HIGH_SHIFT
+#endif
+ .endm
+
.macro kpti_mk_tbl_ng, type, num_entries
add end_\type\()p, cur_\type\()p, #\num_entries * 8
.Ldo_\type:
- ldr \type, [cur_\type\()p] // Load the entry
+ ldr \type, [cur_\type\()p], #8 // Load the entry and advance
tbz \type, #0, .Lnext_\type // Skip invalid and
tbnz \type, #11, .Lnext_\type // non-global entries
orr \type, \type, #PTE_NG // Same bit for blocks and pages
- str \type, [cur_\type\()p] // Update the entry
+ str \type, [cur_\type\()p, #-8] // Update the entry
.ifnc \type, pte
tbnz \type, #1, .Lderef_\type
.endif
.Lnext_\type:
- add cur_\type\()p, cur_\type\()p, #8
cmp cur_\type\()p, end_\type\()p
b.ne .Ldo_\type
.endm
@@ -225,18 +234,18 @@ SYM_FUNC_END(idmap_cpu_replace_ttbr1)
* fixmap slot associated with the current level.
*/
.macro kpti_map_pgtbl, type, level
- str xzr, [temp_pte, #8 * (\level + 1)] // break before make
+ str xzr, [temp_pte, #8 * (\level + 2)] // break before make
dsb nshst
- add pte, temp_pte, #PAGE_SIZE * (\level + 1)
+ add pte, temp_pte, #PAGE_SIZE * (\level + 2)
lsr pte, pte, #12
tlbi vaae1, pte
dsb nsh
isb
phys_to_pte pte, cur_\type\()p
- add cur_\type\()p, temp_pte, #PAGE_SIZE * (\level + 1)
+ add cur_\type\()p, temp_pte, #PAGE_SIZE * (\level + 2)
orr pte, pte, pte_flags
- str pte, [temp_pte, #8 * (\level + 1)]
+ str pte, [temp_pte, #8 * (\level + 2)]
dsb nshst
.endm
@@ -269,6 +278,8 @@ SYM_TYPED_FUNC_START(idmap_kpti_install_ng_mappings)
end_ptep .req x15
pte .req x16
valid .req x17
+ cur_p4dp .req x19
+ end_p4dp .req x20
mov x5, x3 // preserve temp_pte arg
mrs swapper_ttb, ttbr1_el1
@@ -276,6 +287,12 @@ SYM_TYPED_FUNC_START(idmap_kpti_install_ng_mappings)
cbnz cpu, __idmap_kpti_secondary
+#if CONFIG_PGTABLE_LEVELS > 4
+ stp x29, x30, [sp, #-32]!
+ mov x29, sp
+ stp x19, x20, [sp, #16]
+#endif
+
/* We're the boot CPU. Wait for the others to catch up */
sevl
1: wfe
@@ -293,9 +310,32 @@ SYM_TYPED_FUNC_START(idmap_kpti_install_ng_mappings)
mov_q pte_flags, KPTI_NG_PTE_FLAGS
/* Everybody is enjoying the idmap, so we can rewrite swapper. */
+
+#ifdef CONFIG_ARM64_LPA2
+ /*
+ * If LPA2 support is configured, but 52-bit virtual addressing is not
+ * enabled at runtime, we will fall back to one level of paging less,
+ * and so we have to walk swapper_pg_dir as if we dereferenced its
+ * address from a PGD level entry, and terminate the PGD level loop
+ * right after.
+ */
+ adrp pgd, swapper_pg_dir // walk &swapper_pg_dir at the next level
+ mov cur_pgdp, end_pgdp // must be equal to terminate the PGD loop
+alternative_if_not ARM64_HAS_VA52
+ b .Lderef_pgd // skip to the next level
+alternative_else_nop_endif
+ /*
+ * LPA2 based 52-bit virtual addressing requires 52-bit physical
+ * addressing to be enabled as well. In this case, the shareability
+ * bits are repurposed as physical address bits, and should not be
+ * set in pte_flags.
+ */
+ bic pte_flags, pte_flags, #PTE_SHARED
+#endif
+
/* PGD */
adrp cur_pgdp, swapper_pg_dir
- kpti_map_pgtbl pgd, 0
+ kpti_map_pgtbl pgd, -1
kpti_mk_tbl_ng pgd, PTRS_PER_PGD
/* Ensure all the updated entries are visible to secondary CPUs */
@@ -308,16 +348,33 @@ SYM_TYPED_FUNC_START(idmap_kpti_install_ng_mappings)
/* Set the flag to zero to indicate that we're all done */
str wzr, [flag_ptr]
+#if CONFIG_PGTABLE_LEVELS > 4
+ ldp x19, x20, [sp, #16]
+ ldp x29, x30, [sp], #32
+#endif
ret
.Lderef_pgd:
+ /* P4D */
+ .if CONFIG_PGTABLE_LEVELS > 4
+ p4d .req x30
+ pte_to_phys cur_p4dp, pgd
+ kpti_map_pgtbl p4d, 0
+ kpti_mk_tbl_ng p4d, PTRS_PER_P4D
+ b .Lnext_pgd
+ .else /* CONFIG_PGTABLE_LEVELS <= 4 */
+ p4d .req pgd
+ .set .Lnext_p4d, .Lnext_pgd
+ .endif
+
+.Lderef_p4d:
/* PUD */
.if CONFIG_PGTABLE_LEVELS > 3
pud .req x10
- pte_to_phys cur_pudp, pgd
+ pte_to_phys cur_pudp, p4d
kpti_map_pgtbl pud, 1
kpti_mk_tbl_ng pud, PTRS_PER_PUD
- b .Lnext_pgd
+ b .Lnext_p4d
.else /* CONFIG_PGTABLE_LEVELS <= 3 */
pud .req pgd
.set .Lnext_pud, .Lnext_pgd
@@ -361,6 +418,9 @@ SYM_TYPED_FUNC_START(idmap_kpti_install_ng_mappings)
.unreq end_ptep
.unreq pte
.unreq valid
+ .unreq cur_p4dp
+ .unreq end_p4dp
+ .unreq p4d
/* Secondary CPUs end up here */
__idmap_kpti_secondary:
@@ -395,8 +455,6 @@ SYM_FUNC_END(idmap_kpti_install_ng_mappings)
*
* Initialise the processor for turning the MMU on.
*
- * Input:
- * x0 - actual number of VA bits (ignored unless VA_BITS > 48)
* Output:
* Return in x0 the value of the SCTLR_EL1 register.
*/
@@ -420,20 +478,21 @@ SYM_FUNC_START(__cpu_setup)
mair .req x17
tcr .req x16
mov_q mair, MAIR_EL1_SET
- mov_q tcr, TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \
- TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \
- TCR_TBI0 | TCR_A1 | TCR_KASAN_SW_FLAGS | TCR_MTE_FLAGS
+ mov_q tcr, TCR_T0SZ(IDMAP_VA_BITS) | TCR_T1SZ(VA_BITS_MIN) | TCR_CACHE_FLAGS | \
+ TCR_SMP_FLAGS | TCR_TG_FLAGS | TCR_KASLR_FLAGS | TCR_ASID16 | \
+ TCR_TBI0 | TCR_A1 | TCR_KASAN_SW_FLAGS | TCR_MTE_FLAGS
tcr_clear_errata_bits tcr, x9, x5
#ifdef CONFIG_ARM64_VA_BITS_52
- sub x9, xzr, x0
- add x9, x9, #64
+ mov x9, #64 - VA_BITS
+alternative_if ARM64_HAS_VA52
tcr_set_t1sz tcr, x9
-#else
- idmap_get_t0sz x9
+#ifdef CONFIG_ARM64_LPA2
+ orr tcr, tcr, #TCR_DS
+#endif
+alternative_else_nop_endif
#endif
- tcr_set_t0sz tcr, x9
/*
* Set the IPS bits in TCR_EL1.
@@ -458,11 +517,26 @@ SYM_FUNC_START(__cpu_setup)
ubfx x1, x1, #ID_AA64MMFR3_EL1_S1PIE_SHIFT, #4
cbz x1, .Lskip_indirection
+ /*
+ * The PROT_* macros describing the various memory types may resolve to
+ * C expressions if they include the PTE_MAYBE_* macros, and so they
+ * can only be used from C code. The PIE_E* constants below are also
+ * defined in terms of those macros, but will mask out those
+ * PTE_MAYBE_* constants, whether they are set or not. So #define them
+ * as 0x0 here so we can evaluate the PIE_E* constants in asm context.
+ */
+
+#define PTE_MAYBE_NG 0
+#define PTE_MAYBE_SHARED 0
+
mov_q x0, PIE_E0
msr REG_PIRE0_EL1, x0
mov_q x0, PIE_E1
msr REG_PIR_EL1, x0
+#undef PTE_MAYBE_NG
+#undef PTE_MAYBE_SHARED
+
mov x0, TCR2_EL1x_PIE
msr REG_TCR2_EL1, x0
diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
index e305b6593c4e..6986827e0d64 100644
--- a/arch/arm64/mm/ptdump.c
+++ b/arch/arm64/mm/ptdump.c
@@ -26,34 +26,6 @@
#include <asm/ptdump.h>
-enum address_markers_idx {
- PAGE_OFFSET_NR = 0,
- PAGE_END_NR,
-#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
- KASAN_START_NR,
-#endif
-};
-
-static struct addr_marker address_markers[] = {
- { PAGE_OFFSET, "Linear Mapping start" },
- { 0 /* PAGE_END */, "Linear Mapping end" },
-#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
- { 0 /* KASAN_SHADOW_START */, "Kasan shadow start" },
- { KASAN_SHADOW_END, "Kasan shadow end" },
-#endif
- { MODULES_VADDR, "Modules start" },
- { MODULES_END, "Modules end" },
- { VMALLOC_START, "vmalloc() area" },
- { VMALLOC_END, "vmalloc() end" },
- { FIXADDR_TOT_START, "Fixmap start" },
- { FIXADDR_TOP, "Fixmap end" },
- { PCI_IO_START, "PCI I/O start" },
- { PCI_IO_END, "PCI I/O end" },
- { VMEMMAP_START, "vmemmap start" },
- { VMEMMAP_START + VMEMMAP_SIZE, "vmemmap end" },
- { -1, NULL },
-};
-
#define pt_dump_seq_printf(m, fmt, args...) \
({ \
if (m) \
@@ -76,6 +48,7 @@ struct pg_state {
struct ptdump_state ptdump;
struct seq_file *seq;
const struct addr_marker *marker;
+ const struct mm_struct *mm;
unsigned long start_address;
int level;
u64 current_prot;
@@ -172,12 +145,12 @@ static const struct prot_bits pte_bits[] = {
struct pg_level {
const struct prot_bits *bits;
- const char *name;
- size_t num;
+ char name[4];
+ int num;
u64 mask;
};
-static struct pg_level pg_level[] = {
+static struct pg_level pg_level[] __ro_after_init = {
{ /* pgd */
.name = "PGD",
.bits = pte_bits,
@@ -187,11 +160,11 @@ static struct pg_level pg_level[] = {
.bits = pte_bits,
.num = ARRAY_SIZE(pte_bits),
}, { /* pud */
- .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD",
+ .name = "PUD",
.bits = pte_bits,
.num = ARRAY_SIZE(pte_bits),
}, { /* pmd */
- .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD",
+ .name = "PMD",
.bits = pte_bits,
.num = ARRAY_SIZE(pte_bits),
}, { /* pte */
@@ -255,6 +228,11 @@ static void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
static const char units[] = "KMGTPE";
u64 prot = 0;
+ /* check if the current level has been folded dynamically */
+ if ((level == 1 && mm_p4d_folded(st->mm)) ||
+ (level == 2 && mm_pud_folded(st->mm)))
+ level = 0;
+
if (level >= 0)
prot = val & pg_level[level].mask;
@@ -316,6 +294,7 @@ void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
st = (struct pg_state){
.seq = s,
.marker = info->markers,
+ .mm = info->mm,
.level = -1,
.ptdump = {
.note_page = note_page,
@@ -339,13 +318,11 @@ static void __init ptdump_initialize(void)
pg_level[i].mask |= pg_level[i].bits[j].mask;
}
-static struct ptdump_info kernel_ptdump_info = {
+static struct ptdump_info kernel_ptdump_info __ro_after_init = {
.mm = &init_mm,
- .markers = address_markers,
- .base_addr = PAGE_OFFSET,
};
-void ptdump_check_wx(void)
+bool ptdump_check_wx(void)
{
struct pg_state st = {
.seq = NULL,
@@ -358,7 +335,7 @@ void ptdump_check_wx(void)
.ptdump = {
.note_page = note_page,
.range = (struct ptdump_range[]) {
- {PAGE_OFFSET, ~0UL},
+ {_PAGE_OFFSET(vabits_actual), ~0UL},
{0, 0}
}
}
@@ -366,19 +343,46 @@ void ptdump_check_wx(void)
ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
- if (st.wx_pages || st.uxn_pages)
+ if (st.wx_pages || st.uxn_pages) {
pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found, %lu non-UXN pages found\n",
st.wx_pages, st.uxn_pages);
- else
+
+ return false;
+ } else {
pr_info("Checked W+X mappings: passed, no W+X pages found\n");
+
+ return true;
+ }
}
static int __init ptdump_init(void)
{
- address_markers[PAGE_END_NR].start_address = PAGE_END;
+ u64 page_offset = _PAGE_OFFSET(vabits_actual);
+ u64 vmemmap_start = (u64)virt_to_page((void *)page_offset);
+ struct addr_marker m[] = {
+ { PAGE_OFFSET, "Linear Mapping start" },
+ { PAGE_END, "Linear Mapping end" },
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
- address_markers[KASAN_START_NR].start_address = KASAN_SHADOW_START;
+ { KASAN_SHADOW_START, "Kasan shadow start" },
+ { KASAN_SHADOW_END, "Kasan shadow end" },
#endif
+ { MODULES_VADDR, "Modules start" },
+ { MODULES_END, "Modules end" },
+ { VMALLOC_START, "vmalloc() area" },
+ { VMALLOC_END, "vmalloc() end" },
+ { vmemmap_start, "vmemmap start" },
+ { VMEMMAP_END, "vmemmap end" },
+ { PCI_IO_START, "PCI I/O start" },
+ { PCI_IO_END, "PCI I/O end" },
+ { FIXADDR_TOT_START, "Fixmap start" },
+ { FIXADDR_TOP, "Fixmap end" },
+ { -1, NULL },
+ };
+ static struct addr_marker address_markers[ARRAY_SIZE(m)] __ro_after_init;
+
+ kernel_ptdump_info.markers = memcpy(address_markers, m, sizeof(m));
+ kernel_ptdump_info.base_addr = page_offset;
+
ptdump_initialize();
ptdump_debugfs_register(&kernel_ptdump_info, "kernel_page_tables");
return 0;
diff --git a/arch/arm64/mm/trans_pgd.c b/arch/arm64/mm/trans_pgd.c
index 7b14df3c6477..5139a28130c0 100644
--- a/arch/arm64/mm/trans_pgd.c
+++ b/arch/arm64/mm/trans_pgd.c
@@ -33,7 +33,7 @@ static void *trans_alloc(struct trans_pgd_info *info)
static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr)
{
- pte_t pte = READ_ONCE(*src_ptep);
+ pte_t pte = __ptep_get(src_ptep);
if (pte_valid(pte)) {
/*
@@ -41,7 +41,7 @@ static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr)
* read only (code, rodata). Clear the RDONLY bit from
* the temporary mappings we use during restore.
*/
- set_pte(dst_ptep, pte_mkwrite_novma(pte));
+ __set_pte(dst_ptep, pte_mkwrite_novma(pte));
} else if ((debug_pagealloc_enabled() ||
is_kfence_address((void *)addr)) && !pte_none(pte)) {
/*
@@ -55,7 +55,7 @@ static void _copy_pte(pte_t *dst_ptep, pte_t *src_ptep, unsigned long addr)
*/
BUG_ON(!pfn_valid(pte_pfn(pte)));
- set_pte(dst_ptep, pte_mkpresent(pte_mkwrite_novma(pte)));
+ __set_pte(dst_ptep, pte_mkpresent(pte_mkwrite_novma(pte)));
}
}
generated by cgit (git 2.34.1) at 2024-05-30 15:14:18 +0000