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Subject: Re: [PATCH v8 00/20] Convert x86 & arm64 to use generic page walk
To:     Steven Price <steven.price@arm.com>, linux-mm@kvack.org,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Mark Rutland <Mark.Rutland@arm.com>, x86@kernel.org,
        Arnd Bergmann <arnd@arndb.de>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Will Deacon <will.deacon@arm.com>,
        linux-kernel@vger.kernel.org,
        =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= <jglisse@redhat.com>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        James Morse <james.morse@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-arm-kernel@lists.infradead.org,
        "Liang, Kan" <kan.liang@linux.intel.com>
References: <20190403141627.11664-1-steven.price@arm.com>
 <4e804c87-1788-8903-ccc9-55953aa6da36@arm.com>
From:   Dave Hansen <dave.hansen@intel.com>
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Message-ID: <3b9561d0-3bde-ef7a-0313-c2cc6216f94d@intel.com>
Date:   Fri, 12 Apr 2019 07:44:37 -0700
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On 4/10/19 7:56 AM, Steven Price wrote:
> Gentle ping: who can take this? Is there anything blocking this series?

First of all, I really appreciate that you tried this.  Every open-coded
page walk has a set of common pitfalls, but is pretty unbounded in what
kinds of bugs it can contain.  I think this at least gets us to the
point where some of those pitfalls won't happen.  That's cool, but I'm a
worried that it hasn't gotten easier in the end.

Linus also had some strong opinions in the past on how page walks should
be written.  He needs to have a look before we go much further.