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Date:   Wed, 3 Dec 2014 14:42:26 +0100
From:   Ralf Baechle <ralf@linux-mips.org>
To:     Lars Persson <lars.persson@axis.com>
Cc:     Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>,
        "linux-mips@linux-mips.org" <linux-mips@linux-mips.org>,
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        "markos.chandras@imgtec.com" <markos.chandras@imgtec.com>
Subject: Re: [PATCH] Revert "MIPS: Remove race window in page fault handling"
Message-ID: <20141203134226.GC16063@linux-mips.org>
References: <20141203032542.15388.17340.stgit@linux-yegoshin>
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Lars,

normally set_pte_at() is invoked in a 

  cache_flush_*()
  set_pte_at()
  tlb_flush_*()

sequence.  So I'm wondering if you're trying to fix something in set_pte_at
that actually ought to be fixed in the cache_flush_*() function.

I'm wondering, have you identified which cache flush function in particular
was used in the sequence in your particular bug's case?

  Ralf