From: Dongli Zhang
Date: Mon, 31 Oct 2016 21:46:09 -0700 (PDT)
> David, I am very sorry for this error and I will be careful the next time.
> Would you please let me know if I should resend a new patch or an incremental
> based on previous one at
> https://git.kernel.org/cgit/linux/kernel/git/da
-de...@lists.xenproject.org,
netdev@vger.kernel.org, boris.ostrov...@oracle.com, david.vra...@citrix.com,
jgr...@suse.com
Sent: Tuesday, November 1, 2016 4:06:27 AM GMT +08:00 Beijing / Chongqing /
Hong Kong / Urumqi
Subject: Re: [PATCH 1/1] xen-netfront: do not cast grant table reference to
signed short
From: Don
From: Dongli Zhang
Date: Mon, 31 Oct 2016 13:38:29 +0800
> While grant reference is of type uint32_t, xen-netfront erroneously casts
> it to signed short in BUG_ON().
>
> This would lead to the xen domU panic during boot-up or migration when it
> is attached with lots of paravirtual devices.
>
>>> On 31.10.16 at 09:28, wrote:
>> > ref = gnttab_claim_grant_reference(&queue->gref_rx_head);
>> > -BUG_ON((signed short)ref < 0);
>> > +WARN_ON_ONCE(IS_ERR_VALUE((unsigned long)ref));
>
>> You really need to cast to plain (or signed) long here -
ber 31, 2016 3:48:03 PM GMT +08:00 Beijing / Chongqing / Hong
Kong / Urumqi
Subject: Re: [Xen-devel] [PATCH 1/1] xen-netfront: do not cast grant table
reference to signed short
>>> On 31.10.16 at 06:38, wrote:
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.
>>> On 31.10.16 at 06:38, wrote:
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.c
> @@ -304,7 +304,7 @@ static void xennet_alloc_rx_buffers(struct netfront_queue
> *queue)
> queue->rx_skbs[id] = skb;
>
> ref = gnttab_claim_grant_reference(&queue-
While grant reference is of type uint32_t, xen-netfront erroneously casts
it to signed short in BUG_ON().
This would lead to the xen domU panic during boot-up or migration when it
is attached with lots of paravirtual devices.
Signed-off-by: Dongli Zhang
---
drivers/net/xen-netfront.c | 4 ++--
