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Date: Sat, 1 Jun 2013 21:19:08 +1000
From: Michael Ellerman <michael@ellerman.id.au>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Subject: Re: [PATCH] powerpc/mm: Always invalidate tlb on hpte invalidate and
 update
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On Fri, May 31, 2013 at 04:33:24PM +0530, Aneesh Kumar K.V wrote:
> From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
> 
> If a hash bucket gets full, we "evict" a more/less random entry from it.
> When we do that we don't invalidate the TLB (hpte_remove) because we assume
> the old translation is still technically "valid". This implies that when
> we are invalidating or updating pte, even if HPTE entry is not valid
> we should do a tlb invalidate.
> 
> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

Has this always been a bug? I assume not.

I'm asking because I have a kernel that's crashing and I'm wondering if
I might need this commit.

cheers