Re: Patch "kvm, mm: account shadow page tables to kmemcg" has been added to the 4.4-stable tree

On Sat, Jul 28, 2018 at 1:11 AM gregkh@linuxfoundation.org wrote:

This is a note to let you know that I've just added the patch titled

kvm, mm: account shadow page tables to kmemcg

to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: kvm-mm-account-shadow-page-tables-to-kmemcg.patch and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

Hi Greg, this patch requires some more changes to be effective on 4.4 kernel as kmem charging is still not in the generic page allocator code path in 4.4.

Shakeel

From d97e5e6160c0e0a23963ec198c7cb1c69e6bf9e8 Mon Sep 17 00:00:00 2001 From: Shakeel Butt shakeelb@google.com Date: Thu, 26 Jul 2018 16:37:45 -0700 Subject: kvm, mm: account shadow page tables to kmemcg MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

From: Shakeel Butt shakeelb@google.com

commit d97e5e6160c0e0a23963ec198c7cb1c69e6bf9e8 upstream.

The size of kvm's shadow page tables corresponds to the size of the guest virtual machines on the system. Large VMs can spend a significant amount of memory as shadow page tables which can not be left as system memory overhead. So, account shadow page tables to the kmemcg.

[shakeelb@google.com: replace (GFP_KERNEL|__GFP_ACCOUNT) with GFP_KERNEL_ACCOUNT] Link: http://lkml.kernel.org/r/20180629140224.205849-1-shakeelb@google.com Link: http://lkml.kernel.org/r/20180627181349.149778-1-shakeelb@google.com Signed-off-by: Shakeel Butt shakeelb@google.com Cc: Michal Hocko mhocko@kernel.org Cc: Johannes Weiner hannes@cmpxchg.org Cc: Vladimir Davydov vdavydov.dev@gmail.com Cc: Paolo Bonzini pbonzini@redhat.com Cc: Greg Thelen gthelen@google.com Cc: Radim Krčmář rkrcmar@redhat.com Cc: Peter Feiner pfeiner@google.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

---

arch/x86/kvm/mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -692,7 +692,7 @@ static int mmu_topup_memory_cache_page(s if (cache->nobjs >= min) return 0; while (cache->nobjs < ARRAY_SIZE(cache->objects)) {

•           page = (void *)__get_free_page(GFP_KERNEL);
  

•           page = (void *)__get_free_page(GFP_KERNEL_ACCOUNT);
            if (!page)
                    return -ENOMEM;
            cache->objects[cache->nobjs++] = page;
  
  
  

Patches currently in stable-queue which might be from shakeelb@google.com are

queue-4.4/kvm-mm-account-shadow-page-tables-to-kmemcg.patch