Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753411AbbGIRXz (ORCPT ); Thu, 9 Jul 2015 13:23:55 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:50100 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751547AbbGIRXu (ORCPT ); Thu, 9 Jul 2015 13:23:50 -0400 Date: Thu, 9 Jul 2015 19:23:38 +0200 From: Peter Zijlstra To: Mikulas Patocka , Ingo Molnar Cc: Andy Lutomirski , Paul Mackerras , Arnaldo Carvalho de Melo , Kees Cook , Andrea Arcangeli , Vince Weaver , "hillf.zj" , Valdis Kletnieks , linux-kernel@vger.kernel.org Subject: [PATCH] x86: Fix static_key in load_mm_cr4() Message-ID: <20150709172338.GC19282@twins.programming.kicks-ass.net> References: <20150708160750.GQ19282@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1298 Lines: 31 Mikulas reported his K6-3 not booting. This is because the static_key confusion struck and bit Andy, this wants to be static_key_false(). Fixes: a66734297f78 ("perf/x86: Add /sys/devices/cpu/rdpmc=2 to allow rdpmc for all tasks") Cc: Andy Lutomirski Reported-by: Mikulas Patocka Tested-by: Mikulas Patocka Signed-off-by: Peter Zijlstra (Intel) --- arch/x86/include/asm/mmu_context.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 5e8daee7c5c9..804a3a6030ca 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -23,7 +23,7 @@ extern struct static_key rdpmc_always_available; static inline void load_mm_cr4(struct mm_struct *mm) { - if (static_key_true(&rdpmc_always_available) || + if (static_key_false(&rdpmc_always_available) || atomic_read(&mm->context.perf_rdpmc_allowed)) cr4_set_bits(X86_CR4_PCE); else -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/