From 58430c5dba7bfe1d132b3c07f0d7a596852ef55c Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 21 Apr 2020 11:20:35 +0200 Subject: x86/tlb: Move __flush_tlb_one_kernel() out of line cpu_tlbstate is exported because various TLB-related functions need access to it, but cpu_tlbstate is sensitive information which should only be accessed by well-contained kernel functions and not be directly exposed to modules. As a fourth step, move __flush_tlb_one_kernel() out of line and hide the native function. The latter can be static when CONFIG_PARAVIRT is disabled. Consolidate the name space while at it and remove the pointless extra wrapper in the paravirt code. No functional change. Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Reviewed-by: Alexandre Chartre Acked-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200421092559.535159540@linutronix.de --- arch/x86/include/asm/pgtable_32.h | 2 +- arch/x86/include/asm/tlbflush.h | 41 +-------------------------------------- arch/x86/mm/init_64.c | 2 +- arch/x86/mm/ioremap.c | 2 +- arch/x86/mm/kmmio.c | 2 +- arch/x86/mm/pat/set_memory.c | 2 +- arch/x86/mm/pgtable_32.c | 2 +- arch/x86/mm/tlb.c | 34 +++++++++++++++++++++++++++++++- 8 files changed, 40 insertions(+), 47 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/include/asm/pgtable_32.h b/arch/x86/include/asm/pgtable_32.h index 0dca7f7aeff2..bd2ed47cb067 100644 --- a/arch/x86/include/asm/pgtable_32.h +++ b/arch/x86/include/asm/pgtable_32.h @@ -60,7 +60,7 @@ void sync_initial_page_table(void); #define kpte_clear_flush(ptep, vaddr) \ do { \ pte_clear(&init_mm, (vaddr), (ptep)); \ - __flush_tlb_one_kernel((vaddr)); \ + flush_tlb_one_kernel((vaddr)); \ } while (0) #endif /* !__ASSEMBLY__ */ diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index 14c5b98aaa51..bbb94f05e1f3 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -143,6 +143,7 @@ static inline unsigned long build_cr3_noflush(pgd_t *pgd, u16 asid) void flush_tlb_local(void); void flush_tlb_global(void); void flush_tlb_one_user(unsigned long addr); +void flush_tlb_one_kernel(unsigned long addr); #ifdef CONFIG_PARAVIRT #include @@ -317,14 +318,6 @@ static inline void cr4_clear_bits(unsigned long mask) local_irq_restore(flags); } -/* - * Mark all other ASIDs as invalid, preserves the current. - */ -static inline void invalidate_other_asid(void) -{ - this_cpu_write(cpu_tlbstate.invalidate_other, true); -} - /* * Save some of cr4 feature set we're using (e.g. Pentium 4MB * enable and PPro Global page enable), so that any CPU's that boot @@ -365,38 +358,6 @@ static inline void __flush_tlb_all(void) } } -/* - * flush one page in the kernel mapping - */ -static inline void __flush_tlb_one_kernel(unsigned long addr) -{ - count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ONE); - - /* - * If PTI is off, then __flush_tlb_one_user() is just INVLPG or its - * paravirt equivalent. Even with PCID, this is sufficient: we only - * use PCID if we also use global PTEs for the kernel mapping, and - * INVLPG flushes global translations across all address spaces. - * - * If PTI is on, then the kernel is mapped with non-global PTEs, and - * __flush_tlb_one_user() will flush the given address for the current - * kernel address space and for its usermode counterpart, but it does - * not flush it for other address spaces. - */ - flush_tlb_one_user(addr); - - if (!static_cpu_has(X86_FEATURE_PTI)) - return; - - /* - * See above. We need to propagate the flush to all other address - * spaces. In principle, we only need to propagate it to kernelmode - * address spaces, but the extra bookkeeping we would need is not - * worth it. - */ - invalidate_other_asid(); -} - #define TLB_FLUSH_ALL -1UL /* diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 9a497ba02440..c7a1c6c23431 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -298,7 +298,7 @@ static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte) * It's enough to flush this one mapping. * (PGE mappings get flushed as well) */ - __flush_tlb_one_kernel(vaddr); + flush_tlb_one_kernel(vaddr); } void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 41536f523a5f..986d57534fd6 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -885,5 +885,5 @@ void __init __early_set_fixmap(enum fixed_addresses idx, set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags)); else pte_clear(&init_mm, addr, pte); - __flush_tlb_one_kernel(addr); + flush_tlb_one_kernel(addr); } diff --git a/arch/x86/mm/kmmio.c b/arch/x86/mm/kmmio.c index 9994353fb75d..dd625898425a 100644 --- a/arch/x86/mm/kmmio.c +++ b/arch/x86/mm/kmmio.c @@ -173,7 +173,7 @@ static int clear_page_presence(struct kmmio_fault_page *f, bool clear) return -1; } - __flush_tlb_one_kernel(f->addr); + flush_tlb_one_kernel(f->addr); return 0; } diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index a28f0c345303..b7fb1f05f257 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -345,7 +345,7 @@ static void __cpa_flush_tlb(void *data) unsigned int i; for (i = 0; i < cpa->numpages; i++) - __flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i))); + flush_tlb_one_kernel(fix_addr(__cpa_addr(cpa, i))); } static void cpa_flush(struct cpa_data *data, int cache) diff --git a/arch/x86/mm/pgtable_32.c b/arch/x86/mm/pgtable_32.c index 0e6700eaa4f9..e1ce59dc558f 100644 --- a/arch/x86/mm/pgtable_32.c +++ b/arch/x86/mm/pgtable_32.c @@ -64,7 +64,7 @@ void set_pte_vaddr(unsigned long vaddr, pte_t pteval) * It's enough to flush this one mapping. * (PGE mappings get flushed as well) */ - __flush_tlb_one_kernel(vaddr); + flush_tlb_one_kernel(vaddr); } unsigned long __FIXADDR_TOP = 0xfffff000; diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 2822602ce60a..ad217ed2a74f 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -876,7 +876,7 @@ static void do_kernel_range_flush(void *info) /* flush range by one by one 'invlpg' */ for (addr = f->start; addr < f->end; addr += PAGE_SIZE) - __flush_tlb_one_kernel(addr); + flush_tlb_one_kernel(addr); } void flush_tlb_kernel_range(unsigned long start, unsigned long end) @@ -918,6 +918,38 @@ unsigned long __get_current_cr3_fast(void) } EXPORT_SYMBOL_GPL(__get_current_cr3_fast); +/* + * Flush one page in the kernel mapping + */ +void flush_tlb_one_kernel(unsigned long addr) +{ + count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ONE); + + /* + * If PTI is off, then __flush_tlb_one_user() is just INVLPG or its + * paravirt equivalent. Even with PCID, this is sufficient: we only + * use PCID if we also use global PTEs for the kernel mapping, and + * INVLPG flushes global translations across all address spaces. + * + * If PTI is on, then the kernel is mapped with non-global PTEs, and + * __flush_tlb_one_user() will flush the given address for the current + * kernel address space and for its usermode counterpart, but it does + * not flush it for other address spaces. + */ + flush_tlb_one_user(addr); + + if (!static_cpu_has(X86_FEATURE_PTI)) + return; + + /* + * See above. We need to propagate the flush to all other address + * spaces. In principle, we only need to propagate it to kernelmode + * address spaces, but the extra bookkeeping we would need is not + * worth it. + */ + this_cpu_write(cpu_tlbstate.invalidate_other, true); +} + /* * Flush one page in the user mapping */ -- cgit v1.2.3