linux-kernel - Re: [PATCH v5 1/7] mce: fix set_mce_nospec to always unmap the whole page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YfvbyKdu812To3KY@infradead.org>
Date:   Thu, 3 Feb 2022 05:42:32 -0800
From:   Christoph Hellwig <hch@...radead.org>
To:     Jane Chu <jane.chu@...cle.com>
Cc:     Christoph Hellwig <hch@...radead.org>,
        "david@...morbit.com" <david@...morbit.com>,
        "djwong@...nel.org" <djwong@...nel.org>,
        "dan.j.williams@...el.com" <dan.j.williams@...el.com>,
        "vishal.l.verma@...el.com" <vishal.l.verma@...el.com>,
        "dave.jiang@...el.com" <dave.jiang@...el.com>,
        "agk@...hat.com" <agk@...hat.com>,
        "snitzer@...hat.com" <snitzer@...hat.com>,
        "dm-devel@...hat.com" <dm-devel@...hat.com>,
        "ira.weiny@...el.com" <ira.weiny@...el.com>,
        "willy@...radead.org" <willy@...radead.org>,
        "vgoyal@...hat.com" <vgoyal@...hat.com>,
        "linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>,
        "nvdimm@...ts.linux.dev" <nvdimm@...ts.linux.dev>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-xfs@...r.kernel.org" <linux-xfs@...r.kernel.org>
Subject: Re: [PATCH v5 1/7] mce: fix set_mce_nospec to always unmap the whole
 page

On Wed, Feb 02, 2022 at 11:07:37PM +0000, Jane Chu wrote:
> On 2/2/2022 1:20 PM, Jane Chu wrote:
> >> Wouldn't it make more sense to move these helpers out of line rather
> >> than exporting _set_memory_present?
> > 
> > Do you mean to move
> >     return change_page_attr_set(&addr, numpages, __pgprot(_PAGE_PRESENT), 0);
> > into clear_mce_nospec() for the x86 arch and get rid of _set_memory_present?
> > If so, sure I'll do that.
> 
> Looks like I can't do that.  It's either exporting 
> _set_memory_present(), or exporting change_page_attr_set().  Perhaps the 
> former is more conventional?

These helpers above means set_mce_nospec and clear_mce_nospec.  If they
are moved to normal functions instead of inlines, there is no need to
export the internals at all.