From 0a9fe8ca844d43f3f547f0e166122b6048121c8f Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 4 Dec 2018 13:37:21 -0800 Subject: x86/mm: Validate kernel_physical_mapping_init() PTE population The usage of __flush_tlb_all() in the kernel_physical_mapping_init() path is not necessary. In general flushing the TLB is not required when updating an entry from the !present state. However, to give confidence in the future removal of TLB flushing in this path, use the new set_pte_safe() family of helpers to assert that the !present assumption is true in this path. [ mingo: Minor readability edits. ] Suggested-by: Peter Zijlstra Suggested-by: Dave Hansen Signed-off-by: Dan Williams Acked-by: Kirill A. Shutemov Acked-by: Peter Zijlstra (Intel) Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Rik van Riel Cc: Sebastian Andrzej Siewior Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/154395944177.32119.8524957429632012270.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar --- include/asm-generic/5level-fixup.h | 1 + include/asm-generic/pgtable-nop4d-hack.h | 1 + include/asm-generic/pgtable-nop4d.h | 1 + include/asm-generic/pgtable-nopud.h | 1 + 4 files changed, 4 insertions(+) (limited to 'include/asm-generic') diff --git a/include/asm-generic/5level-fixup.h b/include/asm-generic/5level-fixup.h index 73474bb52344..bb6cb347018c 100644 --- a/include/asm-generic/5level-fixup.h +++ b/include/asm-generic/5level-fixup.h @@ -26,6 +26,7 @@ #define p4d_clear(p4d) pgd_clear(p4d) #define p4d_val(p4d) pgd_val(p4d) #define p4d_populate(mm, p4d, pud) pgd_populate(mm, p4d, pud) +#define p4d_populate_safe(mm, p4d, pud) pgd_populate(mm, p4d, pud) #define p4d_page(p4d) pgd_page(p4d) #define p4d_page_vaddr(p4d) pgd_page_vaddr(p4d) diff --git a/include/asm-generic/pgtable-nop4d-hack.h b/include/asm-generic/pgtable-nop4d-hack.h index 1d6dd38c0e5e..829bdb0d6327 100644 --- a/include/asm-generic/pgtable-nop4d-hack.h +++ b/include/asm-generic/pgtable-nop4d-hack.h @@ -31,6 +31,7 @@ static inline void pgd_clear(pgd_t *pgd) { } #define pud_ERROR(pud) (pgd_ERROR((pud).pgd)) #define pgd_populate(mm, pgd, pud) do { } while (0) +#define pgd_populate_safe(mm, pgd, pud) do { } while (0) /* * (puds are folded into pgds so this doesn't get actually called, * but the define is needed for a generic inline function.) diff --git a/include/asm-generic/pgtable-nop4d.h b/include/asm-generic/pgtable-nop4d.h index 04cb913797bc..aebab905e6cd 100644 --- a/include/asm-generic/pgtable-nop4d.h +++ b/include/asm-generic/pgtable-nop4d.h @@ -26,6 +26,7 @@ static inline void pgd_clear(pgd_t *pgd) { } #define p4d_ERROR(p4d) (pgd_ERROR((p4d).pgd)) #define pgd_populate(mm, pgd, p4d) do { } while (0) +#define pgd_populate_safe(mm, pgd, p4d) do { } while (0) /* * (p4ds are folded into pgds so this doesn't get actually called, * but the define is needed for a generic inline function.) diff --git a/include/asm-generic/pgtable-nopud.h b/include/asm-generic/pgtable-nopud.h index 9bef475db6fe..c77a1d301155 100644 --- a/include/asm-generic/pgtable-nopud.h +++ b/include/asm-generic/pgtable-nopud.h @@ -35,6 +35,7 @@ static inline void p4d_clear(p4d_t *p4d) { } #define pud_ERROR(pud) (p4d_ERROR((pud).p4d)) #define p4d_populate(mm, p4d, pud) do { } while (0) +#define p4d_populate_safe(mm, p4d, pud) do { } while (0) /* * (puds are folded into p4ds so this doesn't get actually called, * but the define is needed for a generic inline function.) -- cgit v1.2.3