From dbd68d8e84c606673ebbcf15862f8c155fa92326 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Sat, 22 Apr 2017 00:01:22 -0700 Subject: [PATCH] x86/mm: Fix flush_tlb_page() on Xen flush_tlb_page() passes a bogus range to flush_tlb_others() and expects the latter to fix it up. native_flush_tlb_others() has the fixup but Xen's version doesn't. Move the fixup to flush_tlb_others(). AFAICS the only real effect is that, without this fix, Xen would flush everything instead of just the one page on remote vCPUs in when flush_tlb_page() was called. Signed-off-by: Andy Lutomirski Reviewed-by: Boris Ostrovsky Cc: Andrew Morton Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Konrad Rzeszutek Wilk Cc: Linus Torvalds Cc: Michal Hocko Cc: Nadav Amit Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Fixes: e7b52ffd45a6 ("x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range") Link: http://lkml.kernel.org/r/10ed0e4dfea64daef10b87fb85df1746999b4dba.1492844372.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/mm/tlb.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index 9db9260a5e9f..6e7bedf69af7 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -263,8 +263,6 @@ void native_flush_tlb_others(const struct cpumask *cpumask, { struct flush_tlb_info info; - if (end == 0) - end = start + PAGE_SIZE; info.flush_mm = mm; info.flush_start = start; info.flush_end = end; @@ -378,7 +376,7 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long start) } if (cpumask_any_but(mm_cpumask(mm), smp_processor_id()) < nr_cpu_ids) - flush_tlb_others(mm_cpumask(mm), mm, start, 0UL); + flush_tlb_others(mm_cpumask(mm), mm, start, start + PAGE_SIZE); preempt_enable(); } -- 2.20.1