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. Cc: Rik van Riel <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Nadav Amit <[email protected]> Cc: Michal Hocko <[email protected]> Cc: Sasha Levin <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Konrad Rzeszutek Wilk <[email protected]> Fixes: e7b52ffd45a6 ("x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range") Signed-off-by: Andy Lutomirski <[email protected]> --- 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(); } -- 2.9.3
