On Wed, Aug 21, 2019 at 07:44:33PM +0000, Nadav Amit wrote: > > On Aug 21, 2019, at 12:13 PM, David Hildenbrand <david@xxxxxxxxxx> wrote: > > > > On 21.08.19 18:34, Nadav Amit wrote: > >>> On Aug 21, 2019, at 9:29 AM, David Hildenbrand <david@xxxxxxxxxx> wrote: > >>> > >>> On 21.08.19 18:23, Nadav Amit wrote: > >>>>> On Aug 21, 2019, at 9:05 AM, David Hildenbrand <david@xxxxxxxxxx> wrote: > >>>>> > >>>>> On 20.08.19 11:16, Nadav Amit wrote: > >>>>>> There is no reason to print warnings when balloon page allocation fails, > >>>>>> as they are expected and can be handled gracefully. Since VMware > >>>>>> balloon now uses balloon-compaction infrastructure, and suppressed these > >>>>>> warnings before, it is also beneficial to suppress these warnings to > >>>>>> keep the same behavior that the balloon had before. > >>>>> > >>>>> I am not sure if that's a good idea. The allocation warnings are usually > >>>>> the only trace of "the user/admin did something bad because he/she tried > >>>>> to inflate the balloon to an unsafe value". Believe me, I processed a > >>>>> couple of such bugreports related to virtio-balloon and the warning were > >>>>> very helpful for that. > >>>> > >>>> Ok, so a message is needed, but does it have to be a generic frightening > >>>> warning? > >>>> > >>>> How about using __GFP_NOWARN, and if allocation do something like: > >>>> > >>>> pr_warn(“Balloon memory allocation failed”); > >>>> > >>>> Or even something more informative? This would surely be less intimidating > >>>> for common users. > >>> > >>> ratelimit would make sense :) > >>> > >>> And yes, this would certainly be nicer. > >> > >> Thanks. I will post v2 of the patch. > > > > As discussed in v2, we already print a warning in virtio-balloon, so I > > am fine with this patch. > > > > Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> > > Michael, > > If it is possible to get it to 5.3, to avoid behavioral change for VMware > balloon users, it would be great. > > Thanks, > Nadav Just back from vacation, I'll try.
