From ddd07b750382adc2b78fdfbec47af8a6e0d8ef37 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 19 Sep 2018 10:50:19 +0200 Subject: [PATCH] x86/mm/cpa: Unconditionally avoid WBINDV when we can CAT has happened, WBINDV is bad (even before CAT blowing away the entire cache on a multi-core platform wasn't nice), try not to use it ever. Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Reviewed-by: Dave Hansen Cc: Bin Yang Cc: Mark Gross Link: https://lkml.kernel.org/r/20180919085947.933674526@infradead.org --- arch/x86/mm/pageattr.c | 18 ++---------------- 1 file changed, 2 insertions(+), 16 deletions(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index b6a4c638f086..bd9b0ac07352 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -319,26 +319,12 @@ static void cpa_flush_array(unsigned long *start, int numpages, int cache, int in_flags, struct page **pages) { unsigned int i, level; -#ifdef CONFIG_PREEMPT - /* - * Avoid wbinvd() because it causes latencies on all CPUs, - * regardless of any CPU isolation that may be in effect. - * - * This should be extended for CAT enabled systems independent of - * PREEMPT because wbinvd() does not respect the CAT partitions and - * this is exposed to unpriviledged users through the graphics - * subsystem. - */ - unsigned long do_wbinvd = 0; -#else - unsigned long do_wbinvd = cache && numpages >= 1024; /* 4M threshold */ -#endif BUG_ON(irqs_disabled() && !early_boot_irqs_disabled); - on_each_cpu(__cpa_flush_all, (void *) do_wbinvd, 1); + flush_tlb_all(); - if (!cache || do_wbinvd) + if (!cache) return; /* -- 2.45.2