The following commit has been merged into the x86/mm branch of tip: Commit-ID: 127ac915c8e1c11b8209393e700ca16be0efabe8 Gitweb: https://git.kernel.org/tip/127ac915c8e1c11b8209393e700ca16be0efabe8 Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Tue, 21 Apr 2020 11:20:34 +02:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Sun, 26 Apr 2020 11:00:29 +02:00 x86/tlb: Move __flush_tlb_one_user() 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 third step, move _flush_tlb_one_user() 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 <tglx@xxxxxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Reviewed-by: Alexandre Chartre <alexandre.chartre@xxxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/20200421092559.428213098@xxxxxxxxxxxxx --- arch/x86/include/asm/paravirt.h | 1 +- arch/x86/include/asm/tlbflush.h | 53 +----------------------------- arch/x86/kernel/paravirt.c | 5 +--- arch/x86/mm/tlb.c | 56 +++++++++++++++++++++++++++++++- arch/x86/platform/uv/tlb_uv.c | 2 +- 5 files changed, 59 insertions(+), 58 deletions(-) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 712e059..dcd6517 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -49,6 +49,7 @@ static inline void slow_down_io(void) void native_flush_tlb_local(void); void native_flush_tlb_global(void); +void native_flush_tlb_one_user(unsigned long addr); static inline void __flush_tlb_local(void) { diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h index d66d16e..14c5b98 100644 --- a/arch/x86/include/asm/tlbflush.h +++ b/arch/x86/include/asm/tlbflush.h @@ -142,11 +142,10 @@ 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); #ifdef CONFIG_PARAVIRT #include <asm/paravirt.h> -#else -#define __flush_tlb_one_user(addr) __native_flush_tlb_one_user(addr) #endif struct tlb_context { @@ -346,54 +345,6 @@ static inline void cr4_set_bits_and_update_boot(unsigned long mask) extern void initialize_tlbstate_and_flush(void); /* - * Given an ASID, flush the corresponding user ASID. We can delay this - * until the next time we switch to it. - * - * See SWITCH_TO_USER_CR3. - */ -static inline void invalidate_user_asid(u16 asid) -{ - /* There is no user ASID if address space separation is off */ - if (!IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) - return; - - /* - * We only have a single ASID if PCID is off and the CR3 - * write will have flushed it. - */ - if (!cpu_feature_enabled(X86_FEATURE_PCID)) - return; - - if (!static_cpu_has(X86_FEATURE_PTI)) - return; - - __set_bit(kern_pcid(asid), - (unsigned long *)this_cpu_ptr(&cpu_tlbstate.user_pcid_flush_mask)); -} - -/* - * flush one page in the user mapping - */ -static inline void __native_flush_tlb_one_user(unsigned long addr) -{ - u32 loaded_mm_asid = this_cpu_read(cpu_tlbstate.loaded_mm_asid); - - asm volatile("invlpg (%0)" ::"r" (addr) : "memory"); - - if (!static_cpu_has(X86_FEATURE_PTI)) - return; - - /* - * Some platforms #GP if we call invpcid(type=1/2) before CR4.PCIDE=1. - * Just use invalidate_user_asid() in case we are called early. - */ - if (!this_cpu_has(X86_FEATURE_INVPCID_SINGLE)) - invalidate_user_asid(loaded_mm_asid); - else - invpcid_flush_one(user_pcid(loaded_mm_asid), addr); -} - -/* * flush everything */ static inline void __flush_tlb_all(void) @@ -432,7 +383,7 @@ static inline void __flush_tlb_one_kernel(unsigned long addr) * kernel address space and for its usermode counterpart, but it does * not flush it for other address spaces. */ - __flush_tlb_one_user(addr); + flush_tlb_one_user(addr); if (!static_cpu_has(X86_FEATURE_PTI)) return; diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 6094b00..5638e4a 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -160,11 +160,6 @@ unsigned paravirt_patch_insns(void *insn_buff, unsigned len, return insn_len; } -static void native_flush_tlb_one_user(unsigned long addr) -{ - __native_flush_tlb_one_user(addr); -} - struct static_key paravirt_steal_enabled; struct static_key paravirt_steal_rq_enabled; diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index d548b98..2822602 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -24,6 +24,7 @@ # define STATIC_NOPV static # define __flush_tlb_local native_flush_tlb_local # define __flush_tlb_global native_flush_tlb_global +# define __flush_tlb_one_user(addr) native_flush_tlb_one_user(addr) #endif /* @@ -118,6 +119,32 @@ static void choose_new_asid(struct mm_struct *next, u64 next_tlb_gen, *need_flush = true; } +/* + * Given an ASID, flush the corresponding user ASID. We can delay this + * until the next time we switch to it. + * + * See SWITCH_TO_USER_CR3. + */ +static inline void invalidate_user_asid(u16 asid) +{ + /* There is no user ASID if address space separation is off */ + if (!IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) + return; + + /* + * We only have a single ASID if PCID is off and the CR3 + * write will have flushed it. + */ + if (!cpu_feature_enabled(X86_FEATURE_PCID)) + return; + + if (!static_cpu_has(X86_FEATURE_PTI)) + return; + + __set_bit(kern_pcid(asid), + (unsigned long *)this_cpu_ptr(&cpu_tlbstate.user_pcid_flush_mask)); +} + static void load_new_mm_cr3(pgd_t *pgdir, u16 new_asid, bool need_flush) { unsigned long new_mm_cr3; @@ -645,7 +672,7 @@ static void flush_tlb_func_common(const struct flush_tlb_info *f, unsigned long addr = f->start; while (addr < f->end) { - __flush_tlb_one_user(addr); + flush_tlb_one_user(addr); addr += 1UL << f->stride_shift; } if (local) @@ -892,6 +919,33 @@ unsigned long __get_current_cr3_fast(void) EXPORT_SYMBOL_GPL(__get_current_cr3_fast); /* + * Flush one page in the user mapping + */ +STATIC_NOPV void native_flush_tlb_one_user(unsigned long addr) +{ + u32 loaded_mm_asid = this_cpu_read(cpu_tlbstate.loaded_mm_asid); + + asm volatile("invlpg (%0)" ::"r" (addr) : "memory"); + + if (!static_cpu_has(X86_FEATURE_PTI)) + return; + + /* + * Some platforms #GP if we call invpcid(type=1/2) before CR4.PCIDE=1. + * Just use invalidate_user_asid() in case we are called early. + */ + if (!this_cpu_has(X86_FEATURE_INVPCID_SINGLE)) + invalidate_user_asid(loaded_mm_asid); + else + invpcid_flush_one(user_pcid(loaded_mm_asid), addr); +} + +void flush_tlb_one_user(unsigned long addr) +{ + __flush_tlb_one_user(addr); +} + +/* * Flush everything */ STATIC_NOPV void native_flush_tlb_global(void) diff --git a/arch/x86/platform/uv/tlb_uv.c b/arch/x86/platform/uv/tlb_uv.c index 6af766c..4ea6969 100644 --- a/arch/x86/platform/uv/tlb_uv.c +++ b/arch/x86/platform/uv/tlb_uv.c @@ -296,7 +296,7 @@ static void bau_process_message(struct msg_desc *mdp, struct bau_control *bcp, flush_tlb_local(); stat->d_alltlb++; } else { - __flush_tlb_one_user(msg->address); + flush_tlb_one_user(msg->address); stat->d_onetlb++; } stat->d_requestee++;
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