Re: [PATCH v3] drivers/char: kmem: disable on arm64

From	Ard Biesheuvel <ard.biesheuvel@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3] drivers/char: kmem: disable on arm64
Date	2017-07-17 19:10 +0200
Message-ID	<u4hGX-7SW-37@gated-at.bofh.it> (permalink)
References	<tUliO-5a4-3@gated-at.bofh.it> <tUpw6-7XX-17@gated-at.bofh.it> <u4f2p-69R-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

On 17 July 2017 at 15:18, gregkh@linuxfoundation.org
<gregkh@linuxfoundation.org> wrote:
> On Tue, Jun 20, 2017 at 01:20:49PM +0200, Ard Biesheuvel wrote:
>> On 20 June 2017 at 08:59, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
>> > As it turns out, arm64 deviates from other architectures in the way it
>> > maps the VMALLOC region: on most (all?) other architectures, it resides
>> > strictly above the kernel's direct mapping of DRAM, but on arm64, this
>> > is the other way around. For instance, for a 48-bit VA configuration,
>> > we have
>> >
>> >   modules : 0xffff000000000000 - 0xffff000008000000   (   128 MB)
>> >   vmalloc : 0xffff000008000000 - 0xffff7dffbfff0000   (129022 GB)
>> >   ...
>> >   vmemmap : 0xffff7e0000000000 - 0xffff800000000000   (  2048 GB maximum)
>> >             0xffff7e0000000000 - 0xffff7e0003ff0000   (    63 MB actual)
>> >   memory  : 0xffff800000000000 - 0xffff8000ffc00000   (  4092 MB)
>> >
>> > This has mostly gone unnoticed until now, but it does appear that it
>> > breaks an assumption in the kcore
>>
>> s/kcore/kmem/
>
> v4?  :)
>

This is already in mainline as 06c35ef1fdf8d955684448683f7e48ac5f15ccfd

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

Re: [PATCH v3] drivers/char: kmem: disable on arm64 "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org> - 2017-07-17 16:20 +0200
  Re: [PATCH v3] drivers/char: kmem: disable on arm64 Ard Biesheuvel <ard.biesheuvel@linaro.org> - 2017-07-17 19:10 +0200

csiph-web