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=-14.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,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 1EF72C433DF for ; Thu, 13 Aug 2020 12:15:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDE8120771 for ; Thu, 13 Aug 2020 12:15:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="xCWRXRnX"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="q2GiVcQN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726651AbgHMMPV (ORCPT ); Thu, 13 Aug 2020 08:15:21 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:58334 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726053AbgHMMPS (ORCPT ); Thu, 13 Aug 2020 08:15:18 -0400 Date: Thu, 13 Aug 2020 12:15:15 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1597320916; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MKkEG/5K5y7F2Yw2IcGjRVzdQIU/oD6i7aVmBszFYnA=; b=xCWRXRnXiOoWcHAZcgC3/FjAuA1dycfTMIhZasTk/qcBKwmMxH7nI1DZXkefX3QX/TdCXZ 2IMmjMZ5aZzMP5qr6jCzy6f+207Yk/97fhZTuSqo+To2FSKrwkAOYvwCPfPvdT7X1DWMNs r+UZBGfWpBPKLpSfmSBcvlqUEjEBfRXw+tsKw6z/HG1CZtLmbShA68BEjrj8idBI6DGbU2 j1g2qQaaY/WcnhT8MaPW2bvAaFJsixNWjKmzdnIjwaBBztn2y7xeZchqXUCZ4B390cZbys tpKh4si6sQ+GoKXjkbb1Z2pxEFRka2z6ZUU0pG94nYLT6NEmJDPfb1MN95Q6TQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1597320916; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MKkEG/5K5y7F2Yw2IcGjRVzdQIU/oD6i7aVmBszFYnA=; b=q2GiVcQNMFken73bLIu8FQGR6L9R1cSiqjRyel5CyzEUDzb1HDaMhyJeqJqej35ZZSF6eu OaM5nwrNmy2MxADQ== From: "tip-bot2 for Sebastian Andrzej Siewior" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/urgent] x86/alternatives: Acquire pte lock with interrupts enabled Cc: Sebastian Andrzej Siewior , Thomas Gleixner , x86 , LKML In-Reply-To: <20200813105026.bvugytmsso6muljw@linutronix.de> References: <20200813105026.bvugytmsso6muljw@linutronix.de> MIME-Version: 1.0 Message-ID: <159732091559.3192.7404769548939834518.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/urgent branch of tip: Commit-ID: a6d996cbd38b42341ad3fce74506b9fdc280e395 Gitweb: https://git.kernel.org/tip/a6d996cbd38b42341ad3fce74506b9fdc280e395 Author: Sebastian Andrzej Siewior AuthorDate: Thu, 13 Aug 2020 12:50:26 +02:00 Committer: Thomas Gleixner CommitterDate: Thu, 13 Aug 2020 14:11:54 +02:00 x86/alternatives: Acquire pte lock with interrupts enabled pte lock is never acquired in-IRQ context so it does not require interrupts to be disabled. The lock is a regular spinlock which cannot be acquired with interrupts disabled on RT. RT complains about pte_lock() in __text_poke() because it's invoked after disabling interrupts. __text_poke() has to disable interrupts as use_temporary_mm() expects interrupts to be off because it invokes switch_mm_irqs_off() and uses per-CPU (current active mm) data. Move the PTE lock handling outside the interrupt disabled region. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Acked-by; Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20200813105026.bvugytmsso6muljw@linutronix.de --- 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 c826cdd..34a1b85 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -874,8 +874,6 @@ static void *__text_poke(void *addr, const void *opcode, size_t len) */ BUG_ON(!pages[0] || (cross_page_boundary && !pages[1])); - 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. @@ -892,6 +890,8 @@ static void *__text_poke(void *addr, const void *opcode, size_t len) */ VM_BUG_ON(!ptep); + local_irq_save(flags); + pte = mk_pte(pages[0], pgprot); set_pte_at(poking_mm, poking_addr, ptep, pte); @@ -941,8 +941,8 @@ static void *__text_poke(void *addr, const void *opcode, size_t len) */ BUG_ON(memcmp(addr, opcode, len)); - pte_unmap_unlock(ptep, ptl); local_irq_restore(flags); + pte_unmap_unlock(ptep, ptl); return addr; }