From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 19 Jul 2011 19:35:07 +0100
From: Matthew Garrett <mjg@redhat.com>
To: Seiji Aguchi <seiji.aguchi@hds.com>
Subject: Re: [RFC][PATCH -mmotm 1/4] Add static function calls of pstore to
	kexec path
Message-ID: <20110719183506.GA23770@srcf.ucam.org>
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On Tue, Jul 19, 2011 at 02:24:27PM -0400, Seiji Aguchi wrote:

> -	mutex_lock(&psinfo->buf_mutex);
> +	switch (reason) {
> +	case KMSG_DUMP_KEXEC:
> +		/* Skip if there is no driver or there is a driver calling
> +		   pstore_register() */
> +		if (!psinfo || !spin_trylock(&pstore_lock))
> +			return;
> +		break;
> +	default:
> +		mutex_lock(&psinfo->buf_mutex);

How is this safe? What happens if there's a pstore access in process 
when you hit this codepath?

-- 
Matthew Garrett | mjg59@srcf.ucam.org