linux-kernel - Re: [RFC][PATCH 4/6] arm, mm: Convert arm to generic tlb

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20120517030551.GA11623@linux-sh.org>
Date:	Thu, 17 May 2012 12:05:52 +0900
From:	Paul Mundt <lethal@...ux-sh.org>
To:	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Catalin Marinas <catalin.marinas@....com>
Cc:	Andrea Arcangeli <aarcange@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Rik van Riel <riel@...hat.com>, Ingo Molnar <mingo@...e.hu>,
	akpm@...ux-foundation.org,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	linux-kernel@...r.kernel.org, linux-arch@...r.kernel.org,
	linux-mm@...ck.org,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	David Miller <davem@...emloft.net>,
	Hugh Dickins <hugh.dickins@...cali.co.uk>,
	Mel Gorman <mel@....ul.ie>, Nick Piggin <npiggin@...nel.dk>,
	Russell King <rmk@....linux.org.uk>,
	Chris Metcalf <cmetcalf@...era.com>,
	Martin Schwidefsky <schwidefsky@...ibm.com>
Subject: Re: [RFC][PATCH 4/6] arm, mm: Convert arm to generic tlb

On Wed, Mar 02, 2011 at 06:59:32PM +0100, Peter Zijlstra wrote:
> Might want to optimize the tlb_flush() function to do a full mm flush
> when the range is 'large', IA64 does this too.
> 
> Cc: Russell King <rmk@....linux.org.uk>
> Signed-off-by: Peter Zijlstra <a.p.zijlstra@...llo.nl>

The current version in tlb-unify blows up due to a missing
tlb_add_flush() definition. I can see in this thread tlb_track_range()
was factored in, but the __pte_free_tlb()/__pmd_free_tlb() semantics have
changed since then. Adding a dumb tlb_add_flush() that wraps in to
tlb_track_range() seems to do the right thing, but someone more familiar
with LPAE and ARM's double PMDs will have to figure out whether the
tlb_track_range() in asm-generic/tlb.h's pmd/pte_free_tlb() are
sufficient to remove the tlb_add_flush() calls or not.

Here's the dumb build fix for now though:

Signed-off-by: Paul Mundt <lethal@...ux-sh.org>

---

diff --git a/arch/arm/include/asm/tlb.h b/arch/arm/include/asm/tlb.h
index 37dbce9..1de4b21 100644
--- a/arch/arm/include/asm/tlb.h
+++ b/arch/arm/include/asm/tlb.h
@@ -38,6 +38,11 @@ __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr);
 
 #include <asm-generic/tlb.h>
 
+static inline void tlb_add_flush(struct mmu_gather *tlb, unsigned long addr)
+{
+	tlb_track_range(tlb, addr, addr + PAGE_SIZE);
+}
+
 static inline void
 __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, unsigned long addr)
 {
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/