linux-kernel - Re: [RFC PATCH 25/26] UBIFS: add debugging stuff

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]

Message-ID: <84144f020804010200k759b342dy7a7da1d7f86e22ec@mail.gmail.com>
Date:	Tue, 1 Apr 2008 12:00:39 +0300
From:	"Pekka Enberg" <penberg@...helsinki.fi>
To:	Artem.Bityutskiy@...ia.com
Cc:	"Artem Bityutskiy" <dedekind@...dex.ru>,
	LKML <linux-kernel@...r.kernel.org>,
	"Adrian Hunter" <ext-adrian.hunter@...ia.com>
Subject: Re: [RFC PATCH 25/26] UBIFS: add debugging stuff

Hi Artem,

On Tue, Apr 1, 2008 at 11:32 AM, Artem Bityutskiy
<Artem.Bityutskiy@...ia.com> wrote:
>  I am not sure what you mean. I would not want to delve into a general
>  discussion of the debugging stuff. I would better talk about specific
>  things. I'll just point you examples of debugging stuff in the kernel
>  in other subsystems which exists and does not hurt anyone. And I believe
>  it is helpful. It is compiled out by default and is enable when it is
>  needed to hunt a bug.
>
>  fs/ext2: ea_idebug(), EXT2FS_DEBUG
>  fs/xfs: #ifdef DEBUG, XFS_LOUD_RECOVERY and so on
>  fs/ocfs2: OCFS2_DEBUG_FS
>  fs/jfs: CONFIG_JFS_DEBUG, assert(), etc
>  fs: DEBUG_EPOLL, #ifdef DEBUG
>  fs/jbd2: assert_spin_locked(), CONFIG_JBD2_DEBUG, etc
>  mm: CONFIG_SLUB_DEBUG, SLABDEBUG, CONFIG_DEBUG_VM, and so on

But they're totally different kind of thing! They're not for disabling
hundreds of debug-only printks sprinkled around the kernel. Instead,
they let you disable well-defined debugging checks for kernel speed
and/or size optimizations. And btw, CONFIG_SLUB_DEBUG is only a kernel
size optimization for CONFIG_EMBEDDED. The SLUB debugging code can be
turned on and off at run-time.

                       Pekka
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/