From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33270C433DF for ; Mon, 6 Jul 2020 16:42:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 036A0206CD for ; Mon, 6 Jul 2020 16:42:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="u4F+7aE2"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="26tDryE3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729672AbgGFQmZ (ORCPT ); Mon, 6 Jul 2020 12:42:25 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:55670 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729500AbgGFQmZ (ORCPT ); Mon, 6 Jul 2020 12:42:25 -0400 From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1594053743; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=gEVJsPceN/fHxYmnHe+PN+piF0gnfPqlWXqfVUDU7n0=; b=u4F+7aE2my96lPVoOS2LTrOc21ynXiTYsV3VJa9JILAfj/rsZOOcfnS/bRmOAcMEGTZfFm Y371V5ozg5XsdwJ+kMPCTPoIT56r/YERxL+GpvRzPyxeQrw1PgsLGe5Yryiv66drBUrKYs SqKHYk/jwN9jkgC4pmj6IFEWoxcte0faSojERkRL8dfPQJPg2r/j1/YbtJ9qhCJJv8htCu YyK0+JpZ9tqEmZuy2Cd4oTPeENl0ptC9cCUa6QC/Nks4WRd7OGlMa5GwVd7fcThU1dbiJN KlI52nL9vnCfhO135LlV+byFf8iIbihX4hmOfBBauiyi7bUMQAFDneio5cRF0Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1594053743; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=gEVJsPceN/fHxYmnHe+PN+piF0gnfPqlWXqfVUDU7n0=; b=26tDryE3GYlZ+P9OoGycBfQ6RjkalWL/LxRPu0njk2xNjWOmvD+kPuBw904JyOQSPzxnwM yUU/N7s7j7CGdGCQ== To: linux-kernel@vger.kernel.org Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , Sebastian Andrzej Siewior Subject: [PATCH] x86/alternatives: Let __text_poke() acquire the pte lock with enabled interrupts Date: Mon, 6 Jul 2020 18:42:15 +0200 Message-Id: <20200706164215.2502730-1-bigeasy@linutronix.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The pte lock is never acquired from an IRQ-off region so it does not require the interrupts to be disabled. RT complains here because the spinlock_t must not be acquired with disabled interrupts. use_temporary_mm() expects interrupts to be off because it invokes switch_mm_irqs_off() and uses per-CPU (current active mm) data. Move local_irq_save() after the the pte lock has been acquired. Move local_irq_restore() after the pte lock has been released. Signed-off-by: Sebastian Andrzej Siewior --- arch/x86/kernel/alternative.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 8fd39ff74a499..7c59a87ebbde8 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -872,8 +872,6 @@ static void *__text_poke(void *addr, const void *opcode= , size_t len) */ BUG_ON(!pages[0] || (cross_page_boundary && !pages[1])); =20 - local_irq_save(flags); - /* * Map the page without the global bit, as TLB flushing is done with * flush_tlb_mm_range(), which is intended for non-global PTEs. @@ -890,6 +888,8 @@ static void *__text_poke(void *addr, const void *opcode= , size_t len) */ VM_BUG_ON(!ptep); =20 + local_irq_save(flags); + pte =3D mk_pte(pages[0], pgprot); set_pte_at(poking_mm, poking_addr, ptep, pte); =20 @@ -939,8 +939,8 @@ static void *__text_poke(void *addr, const void *opcode= , size_t len) */ BUG_ON(memcmp(addr, opcode, len)); =20 - pte_unmap_unlock(ptep, ptl); local_irq_restore(flags); + pte_unmap_unlock(ptep, ptl); return addr; } =20 --=20 2.27.0