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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9E120C433EF for ; Mon, 18 Jul 2022 19:37:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236240AbiGRThc (ORCPT ); Mon, 18 Jul 2022 15:37:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57534 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236188AbiGRThR (ORCPT ); Mon, 18 Jul 2022 15:37:17 -0400 Received: from mail-pg1-x530.google.com (mail-pg1-x530.google.com [IPv6:2607:f8b0:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D68130541 for ; Mon, 18 Jul 2022 12:37:15 -0700 (PDT) Received: by mail-pg1-x530.google.com with SMTP id s27so11490852pga.13 for ; Mon, 18 Jul 2022 12:37:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=pKws8yGRo63vLoo5PvEhs398wa0pzhCZmm6r0b5wNuc=; b=qMpMBqoEJowM7hHEVUp4urmfW4BmRk2K5WRu6rjNNtcGI/q+u2qcbzoTj0dymzU/YN GICq1D6c+IwKTAtMkM/ialUwiAbHd2qyav/oi4Lb2/tQir2MH5L1/9FN/OSYwOL11ogc J95A/oNh44qpCzubW1bL4lW6pv2SZPldzPpGkHfXoFe/mJfk3/K11+ZWWai+ZuaWUxuj ZktYEG+NaXZRrAZnM4dfOCYWFErlRI/RQXv4NrUjDJOmLWof5hAYkt6ED39XDfIu11Ol QDBHOQm0nz2tV3l6dVnFXwCweU/mVRE1/C2vxelapt4M8n9mqIfwuSDyhKsokwR/n6pa 5lRA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=pKws8yGRo63vLoo5PvEhs398wa0pzhCZmm6r0b5wNuc=; b=p19nGqIbcAFUMXODGLbp5jyjrhLm3T5bzu5wCgv5behm4KjNDftIlVhBcghfbm/w5V nDHfxuVqq01uLqLnsswCfLjADBO1LUD0Y795bEDV5QMiNzkahi+qNKl76EJLgNN74BUB RhcMjuBqjwBrwf+UnSwTa/uzvvKh3LGK0ecJKQc0TdGj4vKbYpl986X2lKMMzTU5gM5l TxjJ4J9O5rjSy3koi/I84TPOX9ZBTLNZwmhbvkUN+oH2FOCJxEWrpDoeQYqIaK5M0+M4 Ok113NBIUa0JHTnM5qVNQeS00ULQ9sNyZFatmzbkDWtdyQR5IR8k6IEw+eDvsXOny8SX XW3g== X-Gm-Message-State: AJIora+M516yro9aU1Oktzw2lt+fkXmZPV3Xiw2fQBdP+1HU3fcHDuRT t+l1/7SiJAioiHTUNvu9cz0= X-Google-Smtp-Source: AGRyM1v2EDFEp/irIA5oLmEjHJRkKj6neMr06kHIqrOuqyOom6q/rRWy9YaOFocxFmxkQmdYOSbCBw== X-Received: by 2002:aa7:9256:0:b0:52a:cbf7:43ea with SMTP id 22-20020aa79256000000b0052acbf743eamr29902665pfp.7.1658173034758; Mon, 18 Jul 2022 12:37:14 -0700 (PDT) Received: from sc2-haas01-esx0118.eng.vmware.com ([66.170.99.1]) by smtp.gmail.com with ESMTPSA id q6-20020a170902a3c600b0016bc4a6ce28sm9907887plb.98.2022.07.18.12.37.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jul 2022 12:37:14 -0700 (PDT) From: Nadav Amit X-Google-Original-From: Nadav Amit To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Andrew Morton , Mike Rapoport , Axel Rasmussen , Nadav Amit , Andrea Arcangeli , Andrew Cooper , Andy Lutomirski , Dave Hansen , David Hildenbrand , Peter Xu , Peter Zijlstra , Thomas Gleixner , Will Deacon , Yu Zhao , Nick Piggin Subject: [RFC PATCH 08/14] x86/mm: introduce flush_tlb_fix_spurious_fault Date: Mon, 18 Jul 2022 05:02:06 -0700 Message-Id: <20220718120212.3180-9-namit@vmware.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220718120212.3180-1-namit@vmware.com> References: <20220718120212.3180-1-namit@vmware.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nadav Amit The next patches introduce relaxed TLB flushes for x86, which would require a full TLB flush upon spurious page-fault. If a spurious page-fault occurs on x86, check if the local TLB generation is out of sync and perform a TLB flush if needed. Cc: Andrea Arcangeli Cc: Andrew Cooper Cc: Andrew Morton Cc: Andy Lutomirski Cc: Dave Hansen Cc: David Hildenbrand Cc: Peter Xu Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Cc: Yu Zhao Cc: Nick Piggin Signed-off-by: Nadav Amit --- arch/x86/include/asm/pgtable.h | 4 +++- arch/x86/mm/tlb.c | 17 +++++++++++++++++ 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 44e2d6f1dbaa..1fbdaff1bb7a 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -1079,7 +1079,9 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, clear_bit(_PAGE_BIT_RW, (unsigned long *)&ptep->pte); } -#define flush_tlb_fix_spurious_fault(vma, address) do { } while (0) +extern void flush_tlb_fix_spurious_fault(struct vm_area_struct *vma, + unsigned long address); +#define flush_tlb_fix_spurious_fault flush_tlb_fix_spurious_fault #define mk_pmd(page, pgprot) pfn_pmd(page_to_pfn(page), (pgprot)) diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c index d400b6d9d246..ff3bcc55435e 100644 --- a/arch/x86/mm/tlb.c +++ b/arch/x86/mm/tlb.c @@ -955,6 +955,23 @@ static void put_flush_tlb_info(void) #endif } +void flush_tlb_fix_spurious_fault(struct vm_area_struct *vma, + unsigned long address) +{ + u32 loaded_mm_asid = this_cpu_read(cpu_tlbstate.loaded_mm_asid); + u64 mm_tlb_gen = atomic64_read(&vma->vm_mm->context.tlb_gen); + u64 local_tlb_gen = this_cpu_read(cpu_tlbstate.ctxs[loaded_mm_asid].tlb_gen); + struct flush_tlb_info *info; + + if (local_tlb_gen == mm_tlb_gen) + return; + + preempt_disable(); + info = get_flush_tlb_info(NULL, 0, TLB_FLUSH_ALL, 0, false, 0); + flush_tlb_func(info); + preempt_enable(); +} + void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, unsigned long end, unsigned int stride_shift, bool freed_tables) -- 2.25.1