linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Alexander Sverdlin <alexander.sverdlin@nokia.com>
To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>,
	linux-mips@vger.kernel.org, Paul Burton <paulburton@kernel.org>,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] MIPS: reserve the memblock right after the kernel
Date: Mon, 9 Nov 2020 11:34:33 +0100	[thread overview]
Message-ID: <1d6a424e-944e-7f21-1f30-989fb61018a8@nokia.com> (raw)
In-Reply-To: <20201107094028.GA4918@alpha.franken.de>

Hello Thomas,

On 07/11/2020 10:40, Thomas Bogendoerfer wrote:
>> Linux doesn't own the memory immediately after the kernel image. On Octeon
>> bootloader places a shared structure right close after the kernel _end,
>> refer to "struct cvmx_bootinfo *octeon_bootinfo" in cavium-octeon/setup.c.
>>
>> If check_kernel_sections_mem() rounds the PFNs up, first memblock_alloc()
>> inside early_init_dt_alloc_memory_arch() <= device_tree_init() returns
>> memory block overlapping with the above octeon_bootinfo structure, which
>> is being overwritten afterwards.
> as this special for Octeon how about added the memblock_reserve
> in octen specific code ?

while the shared structure which is being corrupted is indeed Octeon-specific,
the wrong assumption that the memory right after the kernel can be allocated by memblock
allocator and re-used somewhere in Linux is in MIPS-generic check_kernel_sections_mem().

I personally will be fine with repairing Octeon only as I don't have other MIPS
targets to care about, but maybe someone else in the MIPS community will find
this fix useful...

-- 
Best regards,
Alexander Sverdlin.

  reply	other threads:[~2020-11-09 10:34 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-06 14:10 [PATCH] MIPS: reserve the memblock right after the kernel Alexander A Sverdlin
2020-11-07  9:40 ` Thomas Bogendoerfer
2020-11-09 10:34   ` Alexander Sverdlin [this message]
2020-11-09 11:08     ` Alexander Sverdlin
2020-11-10  9:55     ` Thomas Bogendoerfer
2020-11-10 10:29       ` Alexander Sverdlin
2020-11-11 14:52         ` Serge Semin
2020-11-13  2:30           ` Jiaxun Yang
2020-11-13  3:28             ` Jinyang He
2020-11-13  3:49               ` Maciej W. Rozycki
2020-11-13 12:29             ` Alexander Sverdlin
2020-11-13 12:56             ` Alexander Sverdlin
2020-11-13  9:17           ` Alexander Sverdlin
2020-11-13 13:09             ` Alexander Sverdlin
2020-11-16 22:31               ` Serge Semin
2020-11-17  9:41                 ` Alexander Sverdlin

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=1d6a424e-944e-7f21-1f30-989fb61018a8@nokia.com \
    --to=alexander.sverdlin@nokia.com \
    --cc=jiaxun.yang@flygoat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@vger.kernel.org \
    --cc=paulburton@kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=tsbogend@alpha.franken.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).