From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3322034-1526420470-5-10736089002469232162 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, MAILING_LIST_MULTI -1, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='com', MailFrom='org' X-Spam-charsets: X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=fm2; t= 1526420470; b=kjInlOOTX/oaOVVenze0Nnafeb9Kaqo6piyBGxGYiL+Bc5kenQ xd2tjke2+gJypO8T5ON5V3IzApH4M1856j49QSJFDBfMwKPr/T4w8HvsmhiV4gYF i7gnDj3BU70/yb6NIsfnkIUI4+vukwT75ch9Vy4eYuD+OKEQDTnqNMMuW/rmT7Sv h8cVITe4Lcpdr/0PXH/uqVgkxDJJiXuE818fxic3/v8823v2tibRsjFffZdlX9u6 9aP9IMBzePXq57ZNMjHYjeJOaBSAd6a+8wyA0EfLR2c5NuLH+xe8kOLbolIv3i// Di5+ainS1nsyI9XcFE+mPv4zvnywsARS8ACA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:sender:list-id; s=fm2; t=1526420470; bh= o8sgoZjOxvubH3vqlI10o5Q7nh1e1mqbGOKF/LOEVSM=; b=hMITiwwxxmHGFA55 M5+wcZuRAZtHpCT8fUItFcGcuFOdO0cXkkro/E+jouC0LeT4p0BOOEV28NqVt9hv ja9k17zTEOOGkUJSrdE72bYspTwgs/QuXKMDiliV+5pzJNYHNkwjDKJs4cOkNZDp uoc+Lfa9h7+cZRrJzfUBU1R9Aemc/a/L8dFDQrn4UwrUxQx9uzydrhraQ0l2GUDB URKenfunvZZ+OJRr1C1D4zNIwGAcDiYbkCrYyV+ImJhGxd1SskC8E7ulA5+0YkuR bge8KonYNd9+5Gc/LBdmzgGZNC3jqgFP+Zb8UulmMWXAzkKpwiRM8DMigU0W8K6B CtaH/g== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=hpe.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=hpe.com header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=hpe.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=hpe.com header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfJPl/MCB7PKBSVTFt8P79Fgs7hvZDAYTa9ikUf6Tn5OaERSVR6cdUZvd6Z3olTU4vjKiJm0+ZWGAVRZPdRRK2NVNCxSHgvavpCLk0a7lA1C4E9EnjosZ 3T4T7rsxd0zCNZiY1fVaF7N4+C05Eq98nI0Y6SALRDOOldYYnyTKedtXzCJ/vArxQrawSxReYqpZITFTM+EUelHPf5OsUNWbjWI10JwD2FXh+trrGZ9+5Agy X-CM-Analysis: v=2.3 cv=E8HjW5Vl c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=VUJBJC2UJ8kA:10 a=MvuuwTCpAAAA:8 a=Z4Rwk6OoAAAA:8 a=iox4zFpeAAAA:8 a=20KFwNOVAAAA:8 a=oGMlB6cnAAAA:8 a=tA7aZXjiAAAA:8 a=VwQbUJbxAAAA:8 a=ICxiNaJX4HUcj9YNticA:9 a=LVWB1rp2qefrMUUt:21 a=29AgWrWh4-N4p5Ih:21 a=dVHiktpip_riXrfdqayU:22 a=HkZW87K1Qel5hWWM3VKY:22 a=WzC6qhA0u3u7Ye7llzcV:22 a=NdAtdrkLVvyUPsUoGJp4:22 a=kIIFJ0VLUOy1gFZzwZHL:22 a=AjGcO6oz07-iQ99wixmX:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752119AbeEOVky (ORCPT ); Tue, 15 May 2018 17:40:54 -0400 Received: from g2t2352.austin.hpe.com ([15.233.44.25]:23599 "EHLO g2t2352.austin.hpe.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752243AbeEOVkw (ORCPT ); Tue, 15 May 2018 17:40:52 -0400 From: Toshi Kani To: mhocko@suse.com, akpm@linux-foundation.org, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com Cc: cpandya@codeaurora.org, linux-mm@kvack.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Toshi Kani , Joerg Roedel , stable@vger.kernel.org Subject: [PATCH v2 3/3] x86/mm: add TLB purge to free pmd/pte page interfaces Date: Tue, 15 May 2018 15:39:31 -0600 Message-Id: <20180515213931.23885-4-toshi.kani@hpe.com> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180515213931.23885-1-toshi.kani@hpe.com> References: <20180515213931.23885-1-toshi.kani@hpe.com> Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: ioremap() calls pud_free_pmd_page() / pmd_free_pte_page() when it creates a pud / pmd map. The following preconditions are met at their entry. - All pte entries for a target pud/pmd address range have been cleared. - System-wide TLB purges have been peformed for a target pud/pmd address range. The preconditions assure that there is no stale TLB entry for the range. Speculation may not cache TLB entries since it requires all levels of page entries, including ptes, to have P & A-bits set for an associated address. However, speculation may cache pud/pmd entries (paging-structure caches) when they have P-bit set. Add a system-wide TLB purge (INVLPG) to a single page after clearing pud/pmd entry's P-bit. SDM 4.10.4.1, Operation that Invalidate TLBs and Paging-Structure Caches, states that: INVLPG invalidates all paging-structure caches associated with the current PCID regardless of the liner addresses to which they correspond. Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces") Signed-off-by: Toshi Kani Cc: Andrew Morton Cc: Michal Hocko Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Joerg Roedel Cc: --- arch/x86/mm/pgtable.c | 34 ++++++++++++++++++++++++++++------ 1 file changed, 28 insertions(+), 6 deletions(-) diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index f60fdf411103..7e96594c7e97 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -721,24 +721,42 @@ int pmd_clear_huge(pmd_t *pmd) * @pud: Pointer to a PUD. * @addr: Virtual address associated with pud. * - * Context: The pud range has been unmaped and TLB purged. + * Context: The pud range has been unmapped and TLB purged. * Return: 1 if clearing the entry succeeded. 0 otherwise. */ int pud_free_pmd_page(pud_t *pud, unsigned long addr) { - pmd_t *pmd; + pmd_t *pmd, *pmd_sv; + pte_t *pte; int i; if (pud_none(*pud)) return 1; pmd = (pmd_t *)pud_page_vaddr(*pud); + pmd_sv = (pmd_t *)__get_free_page(GFP_KERNEL); + if (!pmd_sv) + return 0; - for (i = 0; i < PTRS_PER_PMD; i++) - if (!pmd_free_pte_page(&pmd[i], addr + (i * PMD_SIZE))) - return 0; + for (i = 0; i < PTRS_PER_PMD; i++) { + pmd_sv[i] = pmd[i]; + if (!pmd_none(pmd[i])) + pmd_clear(&pmd[i]); + } pud_clear(pud); + + /* INVLPG to clear all paging-structure caches */ + flush_tlb_kernel_range(addr, addr + PAGE_SIZE-1); + + for (i = 0; i < PTRS_PER_PMD; i++) { + if (!pmd_none(pmd_sv[i])) { + pte = (pte_t *)pmd_page_vaddr(pmd_sv[i]); + free_page((unsigned long)pte); + } + } + + free_page((unsigned long)pmd_sv); free_page((unsigned long)pmd); return 1; @@ -749,7 +767,7 @@ int pud_free_pmd_page(pud_t *pud, unsigned long addr) * @pmd: Pointer to a PMD. * @addr: Virtual address associated with pmd. * - * Context: The pmd range has been unmaped and TLB purged. + * Context: The pmd range has been unmapped and TLB purged. * Return: 1 if clearing the entry succeeded. 0 otherwise. */ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) @@ -761,6 +779,10 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) pte = (pte_t *)pmd_page_vaddr(*pmd); pmd_clear(pmd); + + /* INVLPG to clear all paging-structure caches */ + flush_tlb_kernel_range(addr, addr + PAGE_SIZE-1); + free_page((unsigned long)pte); return 1;