From mboxrd@z Thu Jan  1 00:00:00 1970
From: Heiko Carstens <heiko.carstens@de.ibm.com>
Subject: Re: [PATCH 2/3] S390: Add virtio hotplug add support
Date: Wed, 25 Aug 2010 10:16:30 +0200
Message-ID: <20100825081630.GE2153@osiris.boeblingen.de.ibm.com>
References: <1282657732-20902-1-git-send-email-agraf@suse.de>
 <1282657732-20902-2-git-send-email-agraf@suse.de>
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Cc: virtualization@lists.linux-foundation.org,
	Rusty Russell <rusty@rustcorp.com.au>,
	Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>,
	Carsten Otte <carsteno@de.ibm.com>, borntraeger@de.ibm.com,
	linux-s390@vger.kernel.org, KVM list <kvm@vger.kernel.org>
To: Alexander Graf <agraf@suse.de>
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On Tue, Aug 24, 2010 at 03:48:51PM +0200, Alexander Graf wrote:
> +static void hotplug_devices(struct work_struct *dummy)
> +{
> +	unsigned int i;
> +	struct kvm_device_desc *d;
> +	struct device *dev;
> +
> +	for (i = 0; i < PAGE_SIZE; i += desc_size(d)) {

This should be 

	for (i = 0; i + desc_size(d) <= PAGE_SIZE; i += desc_size(d)) {

otherwise you might have memory accesses beyond the device page...

> +		d = kvm_devices + i;
> +
> +		/* end of list */
> +		if (d->type == 0)
> +			break;

...even if that should not happen if everything works.
But let's be paranoid.