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Date:   Mon, 7 Feb 2022 09:39:31 -0800
From:   Michel Lespinasse <michel@lespinasse.org>
To:     Liam Howlett <liam.howlett@oracle.com>
Cc:     Michel Lespinasse <michel@lespinasse.org>,
        Linux-MM <linux-mm@kvack.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Laurent Dufour <ldufour@linux.ibm.com>,
        Jerome Glisse <jglisse@google.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Michal Hocko <mhocko@suse.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Davidlohr Bueso <dave@stgolabs.net>,
        Matthew Wilcox <willy@infradead.org>,
        Rik van Riel <riel@surriel.com>,
        Paul McKenney <paulmck@kernel.org>,
        Song Liu <songliubraving@fb.com>,
        Suren Baghdasaryan <surenb@google.com>,
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        Joel Fernandes <joelaf@google.com>,
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        Axel Rasmussen <axelrasmussen@google.com>,
        Andy Lutomirski <luto@kernel.org>
Subject: Re: [PATCH v2 13/35] x86/mm: attempt speculative mm faults first
Message-ID: <20220207173931.GC12302@lespinasse.org>
References: <20220128131006.67712-1-michel@lespinasse.org>
 <20220128131006.67712-14-michel@lespinasse.org>
 <20220201171617.z5zgafitgolyv5np@revolver>
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On Tue, Feb 01, 2022 at 05:16:43PM +0000, Liam Howlett wrote:
> > +	vma = __find_vma(mm, address);
> > +	if (!vma || vma->vm_start > address) {
> 
> This fits the vma_lookup() pattern - although you will have to work
> around the locking issue still.  This is the same for the other
> platforms too; they fit the pattern also.

In this case, I think it's just as well to follow the lines of the
non-speculative path, which itself can't use vma_lookup() because it
needs to handle the stack expansion case...

--
Michel "walken" Lespinasse