From 721066dfd4d5c0fee5772c777d6930d0f423b4eb Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 3 Dec 2018 18:03:44 +0100 Subject: [PATCH] x86/mm/cpa: Fix cpa_flush_array() TLB invalidation In commit: a7295fd53c39 ("x86/mm/cpa: Use flush_tlb_kernel_range()") I misread the CAP array code and incorrectly used tlb_flush_kernel_range(), resulting in missing TLB flushes and consequent failures. Instead do a full invalidate in this case -- for now. Reported-by: StDenis, Tom Signed-off-by: Peter Zijlstra (Intel) Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: dave.hansen@intel.com Fixes: a7295fd53c39 ("x86/mm/cpa: Use flush_tlb_kernel_range()") Link: http://lkml.kernel.org/r/20181203171043.089868285@infradead.org Signed-off-by: Ingo Molnar --- arch/x86/mm/pageattr.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index db7a10082238..a1bcde35db4c 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -285,20 +285,16 @@ static void cpa_flush_all(unsigned long cache) on_each_cpu(__cpa_flush_all, (void *) cache, 1); } -static bool __cpa_flush_range(unsigned long start, int numpages, int cache) +static bool __inv_flush_all(int cache) { BUG_ON(irqs_disabled() && !early_boot_irqs_disabled); - WARN_ON(PAGE_ALIGN(start) != start); - if (cache && !static_cpu_has(X86_FEATURE_CLFLUSH)) { cpa_flush_all(cache); return true; } - flush_tlb_kernel_range(start, start + PAGE_SIZE * numpages); - - return !cache; + return false; } static void cpa_flush_range(unsigned long start, int numpages, int cache) @@ -306,7 +302,14 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache) unsigned int i, level; unsigned long addr; - if (__cpa_flush_range(start, numpages, cache)) + WARN_ON(PAGE_ALIGN(start) != start); + + if (__inv_flush_all(cache)) + return; + + flush_tlb_kernel_range(start, start + PAGE_SIZE * numpages); + + if (!cache) return; /* @@ -332,7 +335,12 @@ static void cpa_flush_array(unsigned long baddr, unsigned long *start, { unsigned int i, level; - if (__cpa_flush_range(baddr, numpages, cache)) + if (__inv_flush_all(cache)) + return; + + flush_tlb_all(); + + if (!cache) return; /* -- 2.30.2