From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S980889AbdDYGi6 (ORCPT <rfc822;w@1wt.eu>);
        Tue, 25 Apr 2017 02:38:58 -0400
Received: from mail-wr0-f196.google.com ([209.85.128.196]:32805 "EHLO
        mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S980873AbdDYGir (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Tue, 25 Apr 2017 02:38:47 -0400
Date: Tue, 25 Apr 2017 08:38:42 +0200
From: Ingo Molnar <mingo@kernel.org>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>,
        "Kirill A. Shutemov" <kirill@shutemov.name>, dvlasenk@redhat.com,
        Andy Lutomirski <luto@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>, brgerst@gmail.com,
        Arnd Bergmann <arnd@arndb.de>, Josh Poimboeuf <jpoimboe@redhat.com>,
        Michal Hocko <mhocko@suse.com>, "H. Peter Anvin" <hpa@zytor.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@amacapital.net>, Borislav Petkov <bp@alien8.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-tip-commits@vger.kernel.org
Subject: Re: [tip:x86/mm] x86: Convert the rest of the code to support p4d_t
Message-ID: <20170425063842.nwop6meglpylxmoz@gmail.com>
References: <20170317185515.8636-7-kirill.shutemov@linux.intel.com>
 <tip-f2a6a7050109e0a5c7a84c70aa6010f682b2f1ee@git.kernel.org>
 <CAA9_cmfrHDRnzPJ2tG4YxnnNDH2VuQ6KrFrvXZ=c8Ys1HKUTCQ@mail.gmail.com>
 <20170424165757.76g6qdm4yf4a5ggx@node.shutemov.name>
 <CAPcyv4hEysH5rdD-WOhS-0+NSFNDnHd3Nm6Cwy-XeGZNkHF3qQ@mail.gmail.com>
 <20170425005702.ccvxdavjo432ccdc@black.fi.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20170425005702.ccvxdavjo432ccdc@black.fi.intel.com>
User-Agent: NeoMutt/20170113 (1.7.2)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org


* Kirill A. Shutemov <kirill.shutemov@linux.intel.com> wrote:

> On Mon, Apr 24, 2017 at 11:42:34AM -0700, Dan Williams wrote:
> > >
> > > I cannot reproduce the issue.
> > >
> > > Could you share your kernel kernel config?
> > 
> > Kernel config available here:
> > https://gist.github.com/djbw/2b99a014396cca9f4406586573be98c0
> 
> Patch below should help. Please check.
> 
> diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
> index a242139df8fe..745e5e183169 100644
> --- a/arch/x86/mm/init_64.c
> +++ b/arch/x86/mm/init_64.c
> @@ -962,7 +962,7 @@ remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
>  			continue;
>  		}
>  
> -		pmd_base = (pmd_t *)pud_page_vaddr(*pud);
> +		pmd_base = pmd_offset(pud, 0);
>  		remove_pmd_table(pmd_base, addr, next, direct);
>  		free_pmd_table(pmd_base, pud);
>  	}
> @@ -988,7 +988,7 @@ remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
>  
>  		BUILD_BUG_ON(p4d_large(*p4d));
>  
> -		pud_base = (pud_t *)p4d_page_vaddr(*p4d);
> +		pud_base = pud_offset(p4d, 0);
>  		remove_pud_table(pud_base, addr, next, direct);
>  		free_pud_table(pud_base, p4d);
>  	}
> @@ -1013,7 +1013,7 @@ remove_pagetable(unsigned long start, unsigned long end, bool direct)
>  		if (!pgd_present(*pgd))
>  			continue;
>  
> -		p4d = (p4d_t *)pgd_page_vaddr(*pgd);
> +		p4d = p4d_offset(pgd, 0);
>  		remove_p4d_table(p4d, addr, next, direct);
>  	}

Type casts are dangerous, chapter 378. I missed them when applying the patches.

Could you please double-check all other type casts introduced by the 5-level 
paging patches, to make sure it's all using natural type conversions?

Thanks,

	Ingo