linux-kernel - [PATCH v2 2/5] arm64: mmu: Drop pXd_present() checks from pXd_free_pYd

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue,  2 Oct 2018 12:06:00 +0100
From:   Will Deacon <will.deacon@....com>
To:     linux-kernel@...r.kernel.org, linux-mm@...ck.org
Cc:     cpandya@...eaurora.org, toshi.kani@....com, tglx@...utronix.de,
        mhocko@...e.com, akpm@...ux-foundation.org,
        sean.j.christopherson@...el.com, Will Deacon <will.deacon@....com>
Subject: [PATCH v2 2/5] arm64: mmu: Drop pXd_present() checks from pXd_free_pYd_table()

Now that the core code checks this for us, we don't need to do it in the
backend.

Cc: Chintan Pandya <cpandya@...eaurora.org>
Cc: Toshi Kani <toshi.kani@....com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Michal Hocko <mhocko@...e.com>
Cc: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@....com>
---
 arch/arm64/mm/mmu.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 8080c9f489c3..0dcb3354d6dd 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -985,10 +985,8 @@ int pmd_free_pte_page(pmd_t *pmdp, unsigned long addr)
 
 	pmd = READ_ONCE(*pmdp);
 
-	if (!pmd_present(pmd))
-		return 1;
 	if (!pmd_table(pmd)) {
-		VM_WARN_ON(!pmd_table(pmd));
+		VM_WARN_ON(1);
 		return 1;
 	}
 
@@ -1008,10 +1006,8 @@ int pud_free_pmd_page(pud_t *pudp, unsigned long addr)
 
 	pud = READ_ONCE(*pudp);
 
-	if (!pud_present(pud))
-		return 1;
 	if (!pud_table(pud)) {
-		VM_WARN_ON(!pud_table(pud));
+		VM_WARN_ON(1);
 		return 1;
 	}
 
-- 
2.1.4