From: Keir Fraser <keir.fraser@eu.citrix.com>
To: Dulloor <dulloor@gmail.com>,
"xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
Subject: Re: tmem and construct_dom0 memory allocation race
Date: Sat, 19 Jun 2010 08:26:35 +0100 [thread overview]
Message-ID: <C8422FBB.17F0A%keir.fraser@eu.citrix.com> (raw)
In-Reply-To: <AANLkTilM1bdg1NhGVLpLTu0RLC2qP1Qo-C273BmG7eam@mail.gmail.com>
On 19/06/2010 00:10, "Dulloor" <dulloor@gmail.com> wrote:
> Following is the sequence :
> - init_tmem allocates a set of pages and sets up dstmem and workmem to
> alloc pages in MP case (with cpu notifiers)
> - construct_dom0 estimates nr_pages by calling avail_domheap_pages
> - On other CPUs, tmem cpu_notifier gets called and allocates pages
> from domheap, making the construct_dom0's estimate stale.
> - construct_dom0 fails
>
> tmem=off or dom0_mem=xxx both solve the problem for now.
Xen boot is pretty serialised. In particular SMP boot, and all cpu
notification calls, should be done before dom0 is constructed. So, have you
actually seen this race?
-- Keir
next prev parent reply other threads:[~2010-06-19 7:26 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-06-18 23:10 tmem and construct_dom0 memory allocation race Dulloor
2010-06-19 7:26 ` Keir Fraser [this message]
2010-06-21 15:35 ` Dan Magenheimer
2010-06-22 7:17 ` Dulloor
2010-06-22 7:36 ` Jan Beulich
2010-06-22 7:38 ` Keir Fraser
2010-06-22 17:23 ` Dan Magenheimer
2010-06-22 18:56 ` Dulloor
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