linux-kernel - Re: [PATCH 25/26] kprobes: Convert to raw

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: <20100112035443.GI5243@nowhere>
Date:	Tue, 12 Jan 2010 04:54:45 +0100
From:	Frederic Weisbecker <fweisbec@...il.com>
To:	John Kacur <jkacur@...hat.com>,
	Masami Hiramatsu <mhiramat@...hat.com>
Cc:	Thomas Gleixner <tglx@...utronix.de>,
	lkml <linux-kernel@...r.kernel.org>, Ingo Molnar <mingo@...e.hu>,
	Clark Williams <williams@...hat.com>
Subject: Re: [PATCH 25/26] kprobes: Convert to raw_spinlocks

On Mon, Jan 11, 2010 at 10:26:55PM +0100, John Kacur wrote:
> Convert locks which cannot be sleeping locks in preempt-rt to raw_spinlocks.
> 
> See also dc23e836d8d25fe5aa4057d54dae2094fbc614f6
> 
> Signed-off-by: John Kacur <jkacur@...hat.com>
> ---
>  include/linux/kprobes.h |    2 +-
>  kernel/kprobes.c        |   34 +++++++++++++++++-----------------
>  2 files changed, 18 insertions(+), 18 deletions(-)
> 
> diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
> index 1b672f7..620df87 100644
> --- a/include/linux/kprobes.h
> +++ b/include/linux/kprobes.h
> @@ -170,7 +170,7 @@ struct kretprobe {
>  	int nmissed;
>  	size_t data_size;
>  	struct hlist_head free_instances;
> -	spinlock_t lock;
> +	raw_spinlock_t lock;
>  };


Indeed, this lock seems to be taken when a probe triggers, which
can happen in about every places/context.

Please add a comment to explain this though.

(Adding Masami in Cc).

--
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/