Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753410AbeAFRvI (ORCPT + 1 other); Sat, 6 Jan 2018 12:51:08 -0500 Received: from mail-vk0-f68.google.com ([209.85.213.68]:34752 "EHLO mail-vk0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752778AbeAFRvG (ORCPT ); Sat, 6 Jan 2018 12:51:06 -0500 X-Google-Smtp-Source: ACJfBotUxenCUU9nKXtmWSHMhXyo7MVEPnxMjJ49MOKyawOtVcgmVAIz7XhqgFOOvytwvkAeVSEzwQ== From: Jike Song To: tglx@linutronix.de Cc: luto@kernel.org, linux-kernel@vger.kernel.org, Jike Song Subject: [PATCH] x86/mm/pti: remove dead logic during user pagetable population Date: Sun, 7 Jan 2018 01:50:59 +0800 Message-Id: <20180106175059.19147-1-albcamus@gmail.com> X-Mailer: git-send-email 2.14.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: Signed-off-by: Jike Song --- arch/x86/mm/pti.c | 28 ++++------------------------ 1 file changed, 4 insertions(+), 24 deletions(-) diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c index 43d4a4a29037..dc611d039bd5 100644 --- a/arch/x86/mm/pti.c +++ b/arch/x86/mm/pti.c @@ -164,12 +164,7 @@ static p4d_t *pti_user_pagetable_walk_p4d(unsigned long address) if (!new_p4d_page) return NULL; - if (pgd_none(*pgd)) { - set_pgd(pgd, __pgd(_KERNPG_TABLE | __pa(new_p4d_page))); - new_p4d_page = 0; - } - if (new_p4d_page) - free_page(new_p4d_page); + set_pgd(pgd, __pgd(_KERNPG_TABLE | __pa(new_p4d_page))); } BUILD_BUG_ON(pgd_large(*pgd) != 0); @@ -194,12 +189,7 @@ static pmd_t *pti_user_pagetable_walk_pmd(unsigned long address) if (!new_pud_page) return NULL; - if (p4d_none(*p4d)) { - set_p4d(p4d, __p4d(_KERNPG_TABLE | __pa(new_pud_page))); - new_pud_page = 0; - } - if (new_pud_page) - free_page(new_pud_page); + set_p4d(p4d, __p4d(_KERNPG_TABLE | __pa(new_pud_page))); } pud = pud_offset(p4d, address); @@ -213,12 +203,7 @@ static pmd_t *pti_user_pagetable_walk_pmd(unsigned long address) if (!new_pmd_page) return NULL; - if (pud_none(*pud)) { - set_pud(pud, __pud(_KERNPG_TABLE | __pa(new_pmd_page))); - new_pmd_page = 0; - } - if (new_pmd_page) - free_page(new_pmd_page); + set_pud(pud, __pud(_KERNPG_TABLE | __pa(new_pmd_page))); } return pmd_offset(pud, address); @@ -251,12 +236,7 @@ static __init pte_t *pti_user_pagetable_walk_pte(unsigned long address) if (!new_pte_page) return NULL; - if (pmd_none(*pmd)) { - set_pmd(pmd, __pmd(_KERNPG_TABLE | __pa(new_pte_page))); - new_pte_page = 0; - } - if (new_pte_page) - free_page(new_pte_page); + set_pmd(pmd, __pmd(_KERNPG_TABLE | __pa(new_pte_page))); } pte = pte_offset_kernel(pmd, address); -- 2.14.3