From: Matt Fleming <matt@codeblueprint.co.uk>
To: Arnd Bergmann <arnd@arndb.de>
Cc: "Compostella, Jeremy" <jeremy.compostella@intel.com>,
Ingo Molnar <mingo@kernel.org>,
linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] efibc: avoid stack overflow warning
Date: Sat, 30 Apr 2016 21:14:49 +0100 [thread overview]
Message-ID: <20160430201449.GL2839@codeblueprint.co.uk> (raw)
In-Reply-To: <1461952128-2135409-1-git-send-email-arnd@arndb.de>
On Fri, 29 Apr, at 07:48:31PM, Arnd Bergmann wrote:
> gcc complains about a newly added file for the EFI Bootloader Control:
>
> drivers/firmware/efi/efibc.c: In function 'efibc_set_variable':
> drivers/firmware/efi/efibc.c:53:1: error: the frame size of 2272 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
>
> The problem is the declaration of a local variable of type
> struct efivar_entry, which is by itself larger than the warning
> limit of 1024 bytes.
>
> We know that the reboot notifiers are not called from a deep stack,
> so this is not an actual bug, but we should still try to rework
> the code to avoid the warning. We also know that reboot notifiers
> are never run concurrently on multiple CPUs, so there is no problem
> in just making the variable 'static'.
I assumed reboot notifiers were guaranteed to be non-concurrent too
but having dug into the callers of kernel_reboot(), I couldn't find
any kind of mutual exclusion.
How/where is this guaranteed?
next prev parent reply other threads:[~2016-04-30 20:14 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-29 17:48 [PATCH] efibc: avoid stack overflow warning Arnd Bergmann
2016-04-30 20:14 ` Matt Fleming [this message]
[not found] ` <20160430201449.GL2839-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
2016-04-30 22:34 ` Arnd Bergmann
2016-04-30 22:34 ` Arnd Bergmann
2016-04-30 22:46 ` Matt Fleming
2016-04-30 22:46 ` Matt Fleming
[not found] ` <20160430224641.GQ2839-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
2016-04-30 23:25 ` Arnd Bergmann
2016-04-30 23:25 ` Arnd Bergmann
2016-05-01 13:13 ` Matt Fleming
2016-05-01 13:13 ` Matt Fleming
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=20160430201449.GL2839@codeblueprint.co.uk \
--to=matt@codeblueprint.co.uk \
--cc=arnd@arndb.de \
--cc=jeremy.compostella@intel.com \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.