From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Michael Ellerman <michael@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org,
"Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Subject: Re: [PATCH] powerpc/mm: Always invalidate tlb on hpte invalidate and update
Date: Sat, 01 Jun 2013 21:44:11 +1000 [thread overview]
Message-ID: <1370087051.3766.40.camel@pasglop> (raw)
In-Reply-To: <20130601111908.GA16571@concordia>
On Sat, 2013-06-01 at 21:19 +1000, Michael Ellerman wrote:
> 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.
Bug got introduced in either
b1022fbd293564de91596b8775340cf41ad5214c or
7e74c3921ad9610c0b49f28b8fc69f7480505841, the jury is still out on
that one :-)
It's unlikely to crash the kernel however (it *can*, it's just unlikely).
Patch is good to have regardless...
Cheers,
Ben.
next prev parent reply other threads:[~2013-06-01 11:44 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-05-31 11:03 [PATCH] powerpc/mm: Always invalidate tlb on hpte invalidate and update Aneesh Kumar K.V
2013-06-01 11:19 ` Michael Ellerman
2013-06-01 11:44 ` Benjamin Herrenschmidt [this message]
2013-06-02 7:26 ` Aneesh Kumar K.V
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1370087051.3766.40.camel@pasglop \
--to=benh@kernel.crashing.org \
--cc=aneesh.kumar@linux.vnet.ibm.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=michael@ellerman.id.au \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.