Messages in this thread | | | Subject | Re: [RFC 2/2] initramfs with digital signature protection | From | "H. Peter Anvin" <> | Date | Fri, 08 Feb 2013 07:49:26 -0800 |
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Yes, but you can't umount rootfs.
"Kasatkin, Dmitry" <dmitry.kasatkin@intel.com> wrote:
>On Wed, Feb 6, 2013 at 6:41 PM, H. Peter Anvin <hpa@zytor.com> wrote: >> The cleanup is not a umount, it is actually a tree walk unlinking the >contents. >> > >Please see that umounting ramfs releases the memory. >There was no forced cleanup. >"cp" copied about 2GB of content. >After umounting we got 2GB back to free RAM... > >kds@kds:~$ sudo mount -t ramfs testramfs /test >kds@kds:~$ sudo cp -r /usr/ /test >kds@kds:~$ du -sm /test >2154 /test >kds@kds:~$ free > total used free shared >buffers cached >Mem: 8058600 7855780 202820 0 24768 >4819136 >-/+ buffers/cache: 3011876 5046724 >Swap: 0 0 0 >kds@kds:~$ sudo umount /test >kds@kds:~$ free > total used free shared >buffers cached >Mem: 8058600 5644864 2413736 0 25268 >2623956 >-/+ buffers/cache: 2995640 5062960 >Swap: 0 0 0 > >The same happens also with tmpfs. > >- Dmitry > >> "Kasatkin, Dmitry" <dmitry.kasatkin@intel.com> wrote: >> >>>On Wed, Feb 6, 2013 at 7:04 AM, H. Peter Anvin <hpa@zytor.com> wrote: >>>> On 02/05/2013 02:09 PM, Kasatkin, Dmitry wrote: >>>>> >>>>> >>>>> It should not be like that. Actually when pre-init exits, cleanup >>>code >>>>> umount tmpfs, which in turn cleanups the RAM. >>>>> >>>> >>>> It doesn't quite... the rootfs is permanent. This is also only one >>>usage >>>> mode: there are quite a few Linux systems running directly out of >>>initramfs. >>>> >>> >>>rootfs is not permanent when it is ramfs. It is cleaned up on switch >>>root. >>>It is easy to find out that it is empty by mounting : mount -t ramfs >>>rootfs /mnt/ >>> >>>In the case of running from normal storage, of course, there is >>>ridicules remove the content. >>> >>>- Dmitry >>> >>> >>>> -hpa >>>> >>>> >>>> -- >>>> H. Peter Anvin, Intel Open Source Technology Center >>>> I work for Intel. I don't speak on their behalf. >>>> >> >> -- >> Sent from my mobile phone. Please excuse brevity and lack of >formatting.
-- Sent from my mobile phone. Please excuse brevity and lack of formatting.
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