linux-kernel - Re: [PATCH 0/3 v11] add reserved e820 ranges to the kdump kernel e820 table

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]

Date:   Thu, 13 Jun 2019 09:18:04 +0800
From:   "dyoung@...hat.com" <dyoung@...hat.com>
To:     Borislav Petkov <bp@...en8.de>
Cc:     "Lendacky, Thomas" <Thomas.Lendacky@....com>,
        Baoquan He <bhe@...hat.com>, lijiang <lijiang@...hat.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "kexec@...ts.infradead.org" <kexec@...ts.infradead.org>,
        "tglx@...utronix.de" <tglx@...utronix.de>,
        "mingo@...hat.com" <mingo@...hat.com>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
        "dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>,
        "luto@...nel.org" <luto@...nel.org>,
        "peterz@...radead.org" <peterz@...radead.org>,
        "x86@...nel.org" <x86@...nel.org>, "hpa@...or.com" <hpa@...or.com>
Subject: Re: [PATCH 0/3 v11] add reserved e820 ranges to the kdump kernel
 e820 table

On 06/12/19 at 08:07pm, Borislav Petkov wrote:
> On Wed, Jun 12, 2019 at 04:52:22PM +0000, Lendacky, Thomas wrote:
> > I think the discussion ended up being that debuginfo wasn't being stripped
> > from the kernel and initrd (mainly the initrd).  What are the sizes of
> > the kernel and initrd that you are loading for kdump via kexec?
> > 
> > From previous post:
> >   kexec -s -p /boot/vmlinuz-5.2.0-rc3+ --initrd=/boot/initrd.img-5.2.0-rc3+
> 
> You mean those sizes?
> 
> $ ls -lh /boot/vmlinuz-5.2.0-rc3+ /boot/initrd.img-5.2.0-rc3+
> -rw-r--r-- 1 root root 7.8M Jun 10 12:53 /boot/initrd.img-5.2.0-rc3+
> -rw-r--r-- 1 root root 6.7M Jun 10 12:53 /boot/vmlinuz-5.2.0-rc3+
> 
> That should fit easily in 256M :)

The final used size is uncompressed size, for example in my case:

$ ls -lth arch/x86/boot/bzImage 
-rw-rw-r-- 1 dyoung dyoung 6.3M May 24 11:19 arch/x86/boot/bzImage
$ ls -lth arch/x86/boot/compressed/vmlinux.bin
-rwxrwxr-x 1 dyoung dyoung 25M May 24 11:19 arch/x86/boot/compressed/vmlinux.bin

The vmlinuz is 6.3M, uncompressed kernel is about 25M, since yours
bzImage is 7.8M, I would expect the final size is around 29M

for initramfs, you can check it by:

$ ls -lth /boot/initramfs-5.0.9-301.fc30.x86_64kdump.img
-rw------- 1 root root 16M May 28 08:59 /boot/initramfs-5.0.9-301.fc30.x86_64kdump.img
$ mkdir tmp
$ cd tmp
$ sudo lsinitrd --unpack /boot/initramfs-5.0.9-301.fc30.x86_64kdump.img
$ du -hs .
46M	.

You can see my kdump initrd is 46M after unpacking.

> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> Good mailing practices for 400: avoid top-posting and trim the reply.

Thanks
Dave