From 7f0a002b5a21302d9f4b29ba83c96cd433ff3769 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Mon, 1 Jun 2020 21:52:40 -0700 Subject: x86/mm: remove vmalloc faulting Remove fault handling on vmalloc areas, as the vmalloc code now takes care of synchronizing changes to all page-tables in the system. Signed-off-by: Joerg Roedel Signed-off-by: Andrew Morton Acked-by: Andy Lutomirski Acked-by: Peter Zijlstra (Intel) Cc: Arnd Bergmann Cc: Christoph Hellwig Cc: Dave Hansen Cc: "H . Peter Anvin" Cc: Ingo Molnar Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: "Rafael J. Wysocki" Cc: Steven Rostedt (VMware) Cc: Thomas Gleixner Cc: Vlastimil Babka Link: http://lkml.kernel.org/r/20200515140023.25469-8-joro@8bytes.org Signed-off-by: Linus Torvalds --- arch/x86/mm/tlb.c | 37 ------------------------------------- 1 file changed, 37 deletions(-) (limited to 'arch/x86/mm/tlb.c') diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 66f96f21a7b6..f3fe261e5936 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -161,34 +161,6 @@ void switch_mm(struct mm_struct *prev, struct mm_struct *next, local_irq_restore(flags); } -static void sync_current_stack_to_mm(struct mm_struct *mm) -{ - unsigned long sp = current_stack_pointer; - pgd_t *pgd = pgd_offset(mm, sp); - - if (pgtable_l5_enabled()) { - if (unlikely(pgd_none(*pgd))) { - pgd_t *pgd_ref = pgd_offset_k(sp); - - set_pgd(pgd, *pgd_ref); - } - } else { - /* - * "pgd" is faked. The top level entries are "p4d"s, so sync - * the p4d. This compiles to approximately the same code as - * the 5-level case. - */ - p4d_t *p4d = p4d_offset(pgd, sp); - - if (unlikely(p4d_none(*p4d))) { - pgd_t *pgd_ref = pgd_offset_k(sp); - p4d_t *p4d_ref = p4d_offset(pgd_ref, sp); - - set_p4d(p4d, *p4d_ref); - } - } -} - static inline unsigned long mm_mangle_tif_spec_ib(struct task_struct *next) { unsigned long next_tif = task_thread_info(next)->flags; @@ -377,15 +349,6 @@ void switch_mm_irqs_off(struct mm_struct *prev, struct mm_struct *next, */ cond_ibpb(tsk); - if (IS_ENABLED(CONFIG_VMAP_STACK)) { - /* - * If our current stack is in vmalloc space and isn't - * mapped in the new pgd, we'll double-fault. Forcibly - * map it. - */ - sync_current_stack_to_mm(next); - } - /* * Stop remote flushes for the previous mm. * Skip kernel threads; we never send init_mm TLB flushing IPIs, -- cgit v1.2.3