From: Baoquan He <bhe@redhat.com>
To: linux-kernel@vger.kernel.org, keescook@chromium.org, mingo@kernel.org
Cc: dave.jiang@intel.com, dan.j.williams@intel.com, hpa@zytor.com,
tglx@linutronix.de, dyoung@redhat.com,
Baoquan He <bhe@redhat.com>
Subject: [PATCH v2 0/3] Handle memmap and mem kernel options in boot stage kaslr
Date: Mon, 24 Apr 2017 10:40:47 +0800 [thread overview]
Message-ID: <1493001650-5793-1-git-send-email-bhe@redhat.com> (raw)
People reported kernel panic occurs during system boots up with mem boot option.
After checking code, several problems are found about memmap= and mem= in boot stage
kaslr.
*) In commit f28442497b5c ("x86/boot: Fix KASLR and memmap= collision"), only one memmap
entry is considered and only the last one if multiple memmap entries are specified.
*) mem= and memmap=nn[KMG] are not considered yet. They are used to limit max address
of system. Kernel can't be randomized to be above the limit.
*) kernel-parameters.txt doesn't tell the updated behaviour of memmap=.
This patchset tries to solve above issues.
Changelog:
v1->v2
a)
The original patch 1/4 has been put in tip:x86/boot and no update,
so it's not included in this post.
b)
Use patch log Ingo reorganized.
c)
lib/ctype.c and lib/cmdline.c are needed for kaslr.c, while those
EXPORT_SYMBOL(x) contained caused failure of build on 32-bit allmodconfig:
......
ld: -r and -shared may not be used together
scripts/Makefile.build:294: recipe for target 'arch/x86/boot/compressed/kaslr.o' failed
......
Disabling the symbol exporting removes the build failure.
d)
Use dynamic allocation to allocate memory to contain copied kernel cmdline
buffer, it's implemented in include/linux/decompress/mm.h.
e)
This patchset sits on top of tip:x86/boot branch.
Baoquan He (3):
KASLR: Parse all memmap entries in cmdline
KASLR: Handle memory limit specified by memmap and mem option
Documentation/kernel-parameters.txt: Update 'memmap=' option
description
Documentation/admin-guide/kernel-parameters.txt | 9 ++
arch/x86/boot/compressed/cmdline.c | 2 +-
arch/x86/boot/compressed/kaslr.c | 185 +++++++++++++++---------
arch/x86/boot/string.c | 8 +
4 files changed, 138 insertions(+), 66 deletions(-)
--
2.5.5
next reply other threads:[~2017-04-24 2:41 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-24 2:40 Baoquan He [this message]
2017-04-24 2:40 ` [PATCH v2 1/3] KASLR: Parse all memmap entries in cmdline Baoquan He
2017-04-24 8:00 ` Dou Liyang
2017-04-24 9:09 ` Baoquan He
2017-04-24 8:48 ` kbuild test robot
2017-04-24 8:48 ` [RFC PATCH] KASLR: mem_avoid_memmap_index can be static kbuild test robot
2017-04-24 9:00 ` Baoquan He
2017-04-24 9:04 ` [kbuild-all] " Fengguang Wu
2017-04-24 9:08 ` Baoquan He
2017-04-24 2:40 ` [PATCH v2 2/3] KASLR: Handle memory limit specified by memmap and mem option Baoquan He
2017-04-24 19:10 ` Kees Cook
2017-04-24 2:40 ` [PATCH v2 3/3] Documentation/kernel-parameters.txt: Update 'memmap=' option description Baoquan He
2017-04-24 3:53 ` Dou Liyang
2017-04-24 6:54 ` Baoquan He
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1493001650-5793-1-git-send-email-bhe@redhat.com \
--to=bhe@redhat.com \
--cc=dan.j.williams@intel.com \
--cc=dave.jiang@intel.com \
--cc=dyoung@redhat.com \
--cc=hpa@zytor.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).