>>> On 21.11.12 at 16:42, Dan Magenheimer <dan.magenhei...@oracle.com> wrote: >> From: Jan Beulich [mailto:jbeul...@suse.com] >> Sent: Wednesday, November 21, 2012 1:21 AM >> To: Dan Magenheimer >> Cc: xen-de...@lists.xen.org; Konrad Wilk; linux-kernel@vger.kernel.org >> Subject: Re: [Xen-devel] [PATCH] xen: tmem: selfballooning should be enabled > when xen tmem is enabled >> >> >>> On 20.11.12 at 23:42, Dan Magenheimer <dan.magenhei...@oracle.com> wrote: >> > Konrad: Any chance this can get in for the upcoming window? >> > (Or is it enough of a bug fix that it can go in at an -rcN?) >> > >> > It was just pointed out to me that some kernels have >> > cleancache and frontswap and xen_tmem enabled but NOT >> > xen_selfballooning! While this configuration should be >> > possible, nearly all kernels that have CONFIG_XEN_TMEM=y should >> > also have CONFIG_XEN_SELFBALLOONING=y, since Transcendent >> > Memory (tmem) for Xen has very limited value without >> > selfballooning. >> > >> > This is probably a result of a Kconfig mistake fixed I think >> > by the patch below. Note that the year-old Oracle UEK2 kernel >> > distro has both CONFIG_XEN_TMEM and CONFIG_XEN_SELFBALLOONING >> > enabled, as does a Fedora 17 kernel update (3.6.6-1.fc17), so >> > the combination should be well tested. Also, Xen tmem (and thus >> > selfballooning) are currently only enabled when a kernel boot >> > parameter is supplied so there is no runtime impact without >> > that boot parameter. >> > >> > Signed-off-by: Dan Magenheimer <dan.magenhei...@oracle.com> >> > >> > diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig >> > index d4dffcd..b5f02f3 100644 >> > --- a/drivers/xen/Kconfig >> > +++ b/drivers/xen/Kconfig >> > @@ -10,9 +10,9 @@ config XEN_BALLOON >> > return unneeded memory to the system. >> > >> > config XEN_SELFBALLOONING >> > - bool "Dynamically self-balloon kernel memory to target" >> >> Why would you want to take away the configurability of this? >> You wanting it always on in your use case doesn't mean everyone >> agrees. This would be the right way only when the option being >> off despite all its dependencies being enabled is actively wrong. > > I'd like it to be configurable, but my config steps > (e.g. yes "" | make oldconfig, after enabling CLEANCACHE and > FRONTSWAP and XEN_TMEM) failed to enable it. Removing the > prompt is the only thing that worked.
If all of the dependencies are enabled, then I can't see why the prompt wouldn't show up. > P.S. I removed the CLEANCACHE dependency because that dependency > is present for XEN_TMEM and I assumed dependencies are transitive. That's correct. Jan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
