From: Kees Cook <keescook@chromium.org>
To: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Vivek Goyal <vgoyal@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
Richard Weinberger <richard.weinberger@gmail.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Cong Ding <dinggnu@gmail.com>, Ingo Molnar <mingo@elte.hu>,
Ingo Molnar <mingo@kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Mathias Krause <minipli@googlemail.com>,
Michael Davidson <md@google.com>,
Thomas Gleixner <tglx@linutronix.de>,
Wei Yongjun <yongjun_wei@trendmicro.com.cn>,
Dave Young <dyoung@redhat.com>,
Kexec Mailing List <kexec@lists.infradead.org>
Subject: Re: [GIT PULL] x86/kaslr for v3.14
Date: Fri, 7 Feb 2014 11:44:47 -0800 [thread overview]
Message-ID: <CAGXu5jKTr1udKiD7mhVEkN2W4z0w687DS=jJMORTT+ny+DqGCg@mail.gmail.com> (raw)
In-Reply-To: <52F52EDA.4080007@linux.intel.com>
On Fri, Feb 7, 2014 at 11:07 AM, H. Peter Anvin <hpa@linux.intel.com> wrote:
> On 02/07/2014 06:49 AM, Vivek Goyal wrote:
>>
>> As a workaround, Dave is currently using "nokaslr" command line parameter
>> for second kernel. He is still facing issues where makedumpfile segment
>> faults. He is looking into it further.
>>
>
> Now, let's state this: kaslr for kdump is almost certainly useless (the
> amount of reserved memory is not enough to provide any meaningful
> randomization, so any randomization needs to happen during the memory
> reservation phase.) So disabling kaslr in the kdump kernel is entirely
> appropriate.
Peter covered everything already, but yeah, kaslr and kdump may not
make a lot of sense together, but regardless, yes, it only examines
e820 for memory space. It has to do all this work before the kernel
decompresses, so it's very early.
-Kees
--
Kees Cook
Chrome OS Security
next prev parent reply other threads:[~2014-02-07 19:44 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-20 16:47 [GIT PULL] x86/kaslr for v3.14 H. Peter Anvin
2014-01-20 22:54 ` Linus Torvalds
2014-01-20 23:00 ` H. Peter Anvin
2014-01-20 23:12 ` Linus Torvalds
2014-01-20 23:13 ` H. Peter Anvin
2014-01-21 9:00 ` Peter Zijlstra
2014-01-21 14:20 ` H. Peter Anvin
2014-01-21 14:39 ` Ingo Molnar
2014-01-21 14:51 ` H. Peter Anvin
2014-01-21 14:56 ` Ingo Molnar
2014-01-21 18:37 ` Kees Cook
2014-01-21 10:27 ` Ingo Molnar
2014-01-21 13:55 ` H. Peter Anvin
2014-01-21 14:03 ` Ingo Molnar
2014-01-21 14:05 ` H. Peter Anvin
2014-01-21 14:14 ` Ingo Molnar
2014-01-21 14:17 ` H. Peter Anvin
2014-01-21 5:18 ` Kees Cook
2014-01-23 9:39 ` Pavel Machek
2014-01-26 10:16 ` Richard Weinberger
2014-01-27 5:33 ` H. Peter Anvin
2014-01-27 6:49 ` Richard Weinberger
2014-01-27 6:51 ` H. Peter Anvin
2014-01-27 7:38 ` Ingo Molnar
2014-01-27 7:43 ` Ingo Molnar
2014-01-27 7:59 ` Richard Weinberger
2014-01-30 22:07 ` Vivek Goyal
2014-01-31 16:57 ` Kees Cook
2014-02-07 14:49 ` Vivek Goyal
2014-02-07 16:04 ` H. Peter Anvin
2014-02-07 16:24 ` Vivek Goyal
2014-02-07 23:16 ` Dave Young
2014-02-07 23:20 ` H. Peter Anvin
2014-02-07 23:28 ` Dave Young
2014-02-07 19:07 ` H. Peter Anvin
2014-02-07 19:44 ` Kees Cook [this message]
2014-01-27 6:52 ` H. Peter Anvin
2014-01-27 7:34 ` Richard Weinberger
2014-01-27 17:05 ` Kees Cook
2014-01-27 17:20 ` Richard Weinberger
2014-01-27 17:24 ` Kees Cook
2014-01-28 6:28 ` Ingo Molnar
2014-01-28 8:25 ` Richard Weinberger
2014-01-28 15:55 ` H. Peter Anvin
2014-01-28 16:25 ` Richard Weinberger
2014-01-28 16:30 ` H. Peter Anvin
2014-01-28 16:51 ` Linus Torvalds
2014-01-28 17:05 ` Ingo Molnar
2014-01-28 17:12 ` Linus Torvalds
2014-01-28 17:24 ` Richard Weinberger
2014-01-28 17:35 ` Linus Torvalds
2014-01-28 17:52 ` Richard Weinberger
2014-01-28 17:56 ` Linus Torvalds
2014-01-28 18:54 ` Richard Weinberger
2014-01-28 19:48 ` Ingo Molnar
2014-01-28 20:07 ` Linus Torvalds
2014-01-28 20:15 ` Borislav Petkov
2014-01-28 20:25 ` Linus Torvalds
2014-01-28 20:28 ` Richard Weinberger
2014-01-28 20:38 ` H. Peter Anvin
2014-01-29 8:25 ` Ingo Molnar
2014-01-29 10:40 ` Borislav Petkov
2014-01-28 20:49 ` Borislav Petkov
2014-01-28 23:37 ` Borislav Petkov
2014-01-28 21:08 ` Dave Jones
2014-01-29 6:36 ` Mike Galbraith
2014-01-29 8:11 ` Ingo Molnar
2014-01-29 8:27 ` Mathias Krause
2014-01-30 9:23 ` Ingo Molnar
2014-01-30 18:15 ` Linus Torvalds
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