From: Thomas Gleixner <[email protected]> The current way of disabling global pages at compile time prevents boot time disabling of Kaiser and creates unnecessary indirections.
Global pages can be supressed by __supported_pte_mask as well. The shadow mappings set PAGE_GLOBAL for the minimal kernel mappings which are required for entry/exit. These mappings are set up manually so the filtering does not take place. Signed-off-by: Thomas Gleixner <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/include/asm/pgtable_types.h | 16 +--------------- arch/x86/mm/init.c | 13 ++++++++++--- arch/x86/mm/pageattr.c | 16 ++++++++-------- 3 files changed, 19 insertions(+), 26 deletions(-) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 503bb6999a75..289dde8a9eb3 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -191,23 +191,9 @@ enum page_cache_mode { #define PAGE_READONLY_EXEC __pgprot(_PAGE_PRESENT | _PAGE_USER | \ _PAGE_ACCESSED) -/* - * Disable global pages for anything using the default - * __PAGE_KERNEL* macros. - * - * PGE will still be enabled and _PAGE_GLOBAL may still be used carefully - * for a few selected kernel mappings which must be visible to userspace, - * when KAISER is enabled, like the entry/exit code and data. - */ -#ifdef CONFIG_KAISER -#define __PAGE_KERNEL_GLOBAL 0 -#else -#define __PAGE_KERNEL_GLOBAL _PAGE_GLOBAL -#endif - #define __PAGE_KERNEL_EXEC \ (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED | \ - __PAGE_KERNEL_GLOBAL) + _PAGE_GLOBAL) #define __PAGE_KERNEL (__PAGE_KERNEL_EXEC | _PAGE_NX) #define __PAGE_KERNEL_RO (__PAGE_KERNEL & ~_PAGE_RW) diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 9618e57d46cf..7c0126835f22 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -161,6 +161,13 @@ struct map_range { static int page_size_mask; +static void enable_global_pages(void) +{ +#ifndef CONFIG_KAISER + __supported_pte_mask |= _PAGE_GLOBAL; +#endif +} + static void __init probe_page_size_mask(void) { /* @@ -179,11 +186,11 @@ static void __init probe_page_size_mask(void) cr4_set_bits_and_update_boot(X86_CR4_PSE); /* Enable PGE if available */ + __supported_pte_mask |= _PAGE_GLOBAL; if (boot_cpu_has(X86_FEATURE_PGE)) { cr4_set_bits_and_update_boot(X86_CR4_PGE); - __supported_pte_mask |= _PAGE_GLOBAL; - } else - __supported_pte_mask &= ~_PAGE_GLOBAL; + enable_global_pages(); + } /* Enable 1 GB linear kernel mappings if available: */ if (direct_gbpages && boot_cpu_has(X86_FEATURE_GBPAGES)) { diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 1b3dbf3b3846..f09d8b362194 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -585,9 +585,9 @@ try_preserve_large_page(pte_t *kpte, unsigned long address, * for the ancient hardware that doesn't support it. */ if (pgprot_val(req_prot) & _PAGE_PRESENT) - pgprot_val(req_prot) |= _PAGE_PSE | __PAGE_KERNEL_GLOBAL; + pgprot_val(req_prot) |= _PAGE_PSE | _PAGE_GLOBAL; else - pgprot_val(req_prot) &= ~(_PAGE_PSE | __PAGE_KERNEL_GLOBAL); + pgprot_val(req_prot) &= ~(_PAGE_PSE | _PAGE_GLOBAL); req_prot = canon_pgprot(req_prot); @@ -705,9 +705,9 @@ __split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address, * for the ancient hardware that doesn't support it. */ if (pgprot_val(ref_prot) & _PAGE_PRESENT) - pgprot_val(ref_prot) |= __PAGE_KERNEL_GLOBAL; + pgprot_val(ref_prot) |= _PAGE_GLOBAL; else - pgprot_val(ref_prot) &= ~__PAGE_KERNEL_GLOBAL; + pgprot_val(ref_prot) &= ~_PAGE_GLOBAL; /* * Get the target pfn from the original entry: @@ -938,9 +938,9 @@ static void populate_pte(struct cpa_data *cpa, * support it. */ if (pgprot_val(pgprot) & _PAGE_PRESENT) - pgprot_val(pgprot) |= __PAGE_KERNEL_GLOBAL; + pgprot_val(pgprot) |= _PAGE_GLOBAL; else - pgprot_val(pgprot) &= ~__PAGE_KERNEL_GLOBAL; + pgprot_val(pgprot) &= ~_PAGE_GLOBAL; pgprot = canon_pgprot(pgprot); @@ -1242,9 +1242,9 @@ static int __change_page_attr(struct cpa_data *cpa, int primary) * support it. */ if (pgprot_val(new_prot) & _PAGE_PRESENT) - pgprot_val(new_prot) |= __PAGE_KERNEL_GLOBAL; + pgprot_val(new_prot) |= _PAGE_GLOBAL; else - pgprot_val(new_prot) &= ~__PAGE_KERNEL_GLOBAL; + pgprot_val(new_prot) &= ~_PAGE_GLOBAL; /* * We need to keep the pfn from the existing PTE, -- 2.14.1
