linux-kernel - Re: [PATCH 0/2] rcu: Transform kfree_rcu() into kvfree

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: <20180207171936.GA12446@bombadil.infradead.org>
Date:   Wed, 7 Feb 2018 09:19:36 -0800
From:   Matthew Wilcox <willy@...radead.org>
To:     Steven Rostedt <rostedt@...dmis.org>
Cc:     Christopher Lameter <cl@...ux.com>,
        "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>,
        Kirill Tkhai <ktkhai@...tuozzo.com>, josh@...htriplett.org,
        mathieu.desnoyers@...icios.com, jiangshanlai@...il.com,
        mingo@...hat.com, penberg@...nel.org, rientjes@...gle.com,
        iamjoonsoo.kim@....com, akpm@...ux-foundation.org,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org,
        brouer@...hat.com, rao.shoaib@...cle.com
Subject: Re: [PATCH 0/2] rcu: Transform kfree_rcu() into kvfree_rcu()

On Wed, Feb 07, 2018 at 12:09:49PM -0500, Steven Rostedt wrote:
> > Maybe lets implement malloc(), free() and realloc() in the kernel to be
> > consistent with user space use as possible? Only use the others
> > allocation variants for special cases.
> 
> They would need to drop the GFP part and default to GFP_KERNEL.

Yes, exactly.

> > So malloc would check allocation sizes and if < 2* PAGE_SIZE use kmalloc()
> > otherwise vmalloc().
> 
> Please no, I hate subtle internal decisions like this. It makes
> debugging much more difficult, when allocating dynamic sized variables.
> When something works at one size but not the other.

You know we already have kvmalloc()?