LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: "Kani, Toshi" <toshi.kani@hpe.com>
To: "tglx@linutronix.de" <tglx@linutronix.de>,
	"hpa@zytor.com" <hpa@zytor.com>,
	"joro@8bytes.org" <joro@8bytes.org>,
	"Hocko, Michal" <MHocko@suse.com>,
	"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
	"mingo@redhat.com" <mingo@redhat.com>
Cc: "linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	"cpandya@codeaurora.org" <cpandya@codeaurora.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"x86@kernel.org" <x86@kernel.org>,
	"stable@vger.kernel.org" <stable@vger.kernel.org>
Subject: Re: [PATCH 3/3] x86/mm: disable ioremap free page handling on x86-PAE
Date: Wed, 9 May 2018 15:47:19 +0000	[thread overview]
Message-ID: <1525880775.2693.558.camel@hpe.com> (raw)
In-Reply-To: <20180430175925.2657-4-toshi.kani@hpe.com>

On Mon, 2018-04-30 at 11:59 -0600, Toshi Kani wrote:
> ioremap() supports pmd mappings on x86-PAE.  However, kernel's pmd
> tables are not shared among processes on x86-PAE.  Therefore, any
> update to sync'd pmd entries need re-syncing.  Freeing a pte page
> also leads to a vmalloc fault and hits the BUG_ON in vmalloc_sync_one().
> 
> Disable free page handling on x86-PAE.  pud_free_pmd_page() and
> pmd_free_pte_page() simply return 0 if a given pud/pmd entry is present.
> This assures that ioremap() does not update sync'd pmd entries at the
> cost of falling back to pte mappings.
> 
> Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces")
> Reported-by: Joerg Roedel <joro@8bytes.org>

Hi Joerg,

Does it solve your problem?  Let me know if you have any issue with the
series. 

Thanks,
-Toshi

      reply	other threads:[~2018-05-09 15:47 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-30 17:59 [PATCH 0/3] fix free pmd/pte page handlings on x86 Toshi Kani
2018-04-30 17:59 ` [PATCH 1/3] ioremap: Update pgtable free interfaces with addr Toshi Kani
2018-04-30 17:59 ` [PATCH 2/3] x86/mm: add TLB purge to free pmd/pte page interfaces Toshi Kani
2018-05-15 14:05   ` Joerg Roedel
2018-05-15 16:34     ` Kani, Toshi
2018-04-30 17:59 ` [PATCH 3/3] x86/mm: disable ioremap free page handling on x86-PAE Toshi Kani
2018-05-09 15:47   ` Kani, Toshi [this message]

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=1525880775.2693.558.camel@hpe.com \
    --to=toshi.kani@hpe.com \
    --cc=MHocko@suse.com \
    --cc=akpm@linux-foundation.org \
    --cc=cpandya@codeaurora.org \
    --cc=hpa@zytor.com \
    --cc=joro@8bytes.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mingo@redhat.com \
    --cc=stable@vger.kernel.org \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    --subject='Re: [PATCH 3/3] x86/mm: disable ioremap free page handling on x86-PAE' \
    /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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).