From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752442AbdIWNFe (ORCPT ); Sat, 23 Sep 2017 09:05:34 -0400 Received: from mail-wr0-f195.google.com ([209.85.128.195]:36622 "EHLO mail-wr0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752002AbdIWNAz (ORCPT ); Sat, 23 Sep 2017 09:00:55 -0400 X-Google-Smtp-Source: AOwi7QATQvckbUfsSFhlpwS/ZchrqQbXJMhKfR42n6Kl4wRYzzSZor736BisU3VBIjguryyO+iEnzg== From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: Andrew Morton , Eric Biggers , Andy Lutomirski , Borislav Petkov , Dave Hansen , Fenghua Yu , "H . Peter Anvin" , Linus Torvalds , Oleg Nesterov , Peter Zijlstra , Rik van Riel , Thomas Gleixner , Yu-cheng Yu Subject: [PATCH 16/33] x86/fpu: Make the fpu state change in fpu__clear() scheduler-atomic Date: Sat, 23 Sep 2017 14:59:59 +0200 Message-Id: <20170923130016.21448-17-mingo@kernel.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170923130016.21448-1-mingo@kernel.org> References: <20170923130016.21448-1-mingo@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Do this temporarily only, to make it easier to change the FPU state machine, in particular this change couples the fpu->fpregs_active and fpu->fpstate_active states: they are only set/cleared together (as far as the scheduler sees them). This will be removed by later patches. Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Yu-cheng Yu Signed-off-by: Ingo Molnar --- arch/x86/kernel/fpu/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index bad57248e5a0..b7dc3833d41a 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -462,9 +462,11 @@ void fpu__clear(struct fpu *fpu) * Make sure fpstate is cleared and initialized. */ if (static_cpu_has(X86_FEATURE_FPU)) { + preempt_disable(); fpu__activate_curr(fpu); user_fpu_begin(); copy_init_fpstate_to_fpregs(); + preempt_enable(); } } -- 2.11.0