From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: More on 2.6.28 and balloon driver Date: Fri, 16 Jan 2009 10:08:16 -0800 Message-ID: <4970CD10.6050707@goop.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Dan Magenheimer Cc: "Xen-Devel (E-mail)" List-Id: xen-devel@lists.xenproject.org Dan Magenheimer wrote: >> It appears that in the upstream balloon driver, >> the call to HYPERVISOR_update_va_mapping is missing >> from decrease_reservation. I think as a result, >> the balloon driver is eating memory but not >> releasing it to Xen, thus rendering the balloon >> driver essentially useless. (Can be observed via xentop.) >> > > Limited testing, but it appears that adding it > back in with this simple patch to linux-2.6.28 > makes ballooning work properly. > Thanks. That's a pretty embarrassing oversight :/ > As the code is lifted from the original Xen balloon driver, > I'm not sure I need this, but: > > Signed-off-by: Dan Magenheimer > Yeah, the S-o-b line is a way to keep track of who a patch went via. It's "I assert that I'm allowed to post this patch". In theory you'd include the previous S-o-b lines (if any), but a reference to the source repo/version would be enough in this case. J > Dan > > P.S. Attachement is same, provided in case my mailer > messes up this >80-char-width patch. > > > --- linux-2.6.28/drivers/xen/balloon.c.orig 2009-01-07 12:35:48.000000000 -0700 > +++ linux-2.6.28/drivers/xen/balloon.c 2009-01-07 12:36:06.000000000 -0700 > @@ -296,6 +296,11 @@ > frame_list[i] = pfn_to_mfn(pfn); > > scrub_page(page); > + > + ret = HYPERVISOR_update_va_mapping( > + (unsigned long)__va(pfn << PAGE_SHIFT), > + __pte_ma(0), 0); > + BUG_ON(ret); > } > > /* Ensure that ballooned highmem pages don't have kmaps. */ > ------------------------------------------------------------------------ > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel >