Re: [PATCH] kvm, mm: account kvm related kmem slabs to kmemcg

From: Paolo Bonzini
Date: Tue Oct 10 2017 - 04:32:38 EST


On 06/10/2017 03:07, Shakeel Butt wrote:
> The kvm slabs can consume a significant amount of system memory
> and indeed in our production environment we have observed that
> a lot of machines are spending significant amount of memory that
> can not be left as system memory overhead. Also the allocations
> from these slabs can be triggered directly by user space applications
> which has access to kvm and thus a buggy application can leak
> such memory. So, these caches should be accounted to kmemcg.
>
> Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
> ---
> arch/x86/kvm/mmu.c | 4 ++--
> virt/kvm/kvm_main.c | 2 +-
> 2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
> index eca30c1eb1d9..87c5db9e644d 100644
> --- a/arch/x86/kvm/mmu.c
> +++ b/arch/x86/kvm/mmu.c
> @@ -5475,13 +5475,13 @@ int kvm_mmu_module_init(void)
>
> pte_list_desc_cache = kmem_cache_create("pte_list_desc",
> sizeof(struct pte_list_desc),
> - 0, 0, NULL);
> + 0, SLAB_ACCOUNT, NULL);
> if (!pte_list_desc_cache)
> goto nomem;
>
> mmu_page_header_cache = kmem_cache_create("kvm_mmu_page_header",
> sizeof(struct kvm_mmu_page),
> - 0, 0, NULL);
> + 0, SLAB_ACCOUNT, NULL);
> if (!mmu_page_header_cache)
> goto nomem;
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 9deb5a245b83..3d73299e05f2 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -4010,7 +4010,7 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
> if (!vcpu_align)
> vcpu_align = __alignof__(struct kvm_vcpu);
> kvm_vcpu_cache = kmem_cache_create("kvm_vcpu", vcpu_size, vcpu_align,
> - 0, NULL);
> + SLAB_ACCOUNT, NULL);
> if (!kvm_vcpu_cache) {
> r = -ENOMEM;
> goto out_free_3;
>

Queued, thanks.

Paolo