From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp06.au.ibm.com (e23smtp06.au.ibm.com [202.81.31.148]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 1EBC41A0009 for ; Wed, 23 Jul 2014 13:36:57 +1000 (EST) Received: from /spool/local by e23smtp06.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 23 Jul 2014 13:36:55 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 9ED4D2BB005C for ; Wed, 23 Jul 2014 13:36:53 +1000 (EST) Received: from d23av01.au.ibm.com (d23av01.au.ibm.com [9.190.234.96]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s6N3aatB9896340 for ; Wed, 23 Jul 2014 13:36:37 +1000 Received: from d23av01.au.ibm.com (localhost [127.0.0.1]) by d23av01.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s6N3aq4c030317 for ; Wed, 23 Jul 2014 13:36:52 +1000 Date: Wed, 23 Jul 2014 13:36:52 +1000 From: Gavin Shan To: Alexey Kardashevskiy Subject: Re: [PATCH v2 03/18] KVM: PPC: Account TCE pages in locked_vm Message-ID: <20140723033652.GC5208@shangw> Reply-To: Gavin Shan References: <1406084764-24685-1-git-send-email-aik@ozlabs.ru> <1406084764-24685-4-git-send-email-aik@ozlabs.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1406084764-24685-4-git-send-email-aik@ozlabs.ru> Cc: linuxppc-dev@lists.ozlabs.org, Gavin Shan , Paul Mackerras List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, Jul 23, 2014 at 01:05:49PM +1000, Alexey Kardashevskiy wrote: >Signed-off-by: Alexey Kardashevskiy >--- > arch/powerpc/kvm/book3s_64_vio.c | 35 ++++++++++++++++++++++++++++++++++- > 1 file changed, 34 insertions(+), 1 deletion(-) > >diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c >index 516f2ee..48b7ed4 100644 >--- a/arch/powerpc/kvm/book3s_64_vio.c >+++ b/arch/powerpc/kvm/book3s_64_vio.c >@@ -45,18 +45,48 @@ static long kvmppc_stt_npages(unsigned long window_size) > * sizeof(u64), PAGE_SIZE) / PAGE_SIZE; > } > >+/* >+ * Checks ulimit in order not to let the user space to pin all >+ * available memory for TCE tables. >+ */ >+static long kvmppc_account_memlimit(long npages) >+{ >+ unsigned long ret = 0, locked, lock_limit; >+ >+ if (!current->mm) >+ return -ESRCH; /* process exited */ >+ >+ down_write(¤t->mm->mmap_sem); >+ locked = current->mm->locked_vm + npages; >+ lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; >+ if (locked > lock_limit && !capable(CAP_IPC_LOCK)) { I took a look on mm/mlock.c::mlock() where the mlock operation is allowd while we have one of following conditions (not &&) :-) /* check against resource limits */ if ((locked <= lock_limit) || capable(CAP_IPC_LOCK)) error = do_mlock(start, len, 1); Thanks, Gavin >+ pr_warn("RLIMIT_MEMLOCK (%ld) exceeded\n", >+ rlimit(RLIMIT_MEMLOCK)); >+ ret = -ENOMEM; >+ } else { >+ current->mm->locked_vm += npages; >+ } >+ up_write(¤t->mm->mmap_sem); >+ >+ return ret; >+} >+ > static void release_spapr_tce_table(struct kvmppc_spapr_tce_table *stt) > { > struct kvm *kvm = stt->kvm; > int i; >+ long npages = kvmppc_stt_npages(stt->window_size); > > mutex_lock(&kvm->lock); > list_del(&stt->list); >- for (i = 0; i < kvmppc_stt_npages(stt->window_size); i++) >+ for (i = 0; i < npages; i++) > __free_page(stt->pages[i]); >+ > kfree(stt); > mutex_unlock(&kvm->lock); > >+ kvmppc_account_memlimit(-(npages + 1)); >+ > kvm_put_kvm(kvm); > } > >@@ -112,6 +142,9 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, > } > > npages = kvmppc_stt_npages(args->window_size); >+ ret = kvmppc_account_memlimit(npages + 1); >+ if (ret) >+ goto fail; > > stt = kzalloc(sizeof(*stt) + npages * sizeof(struct page *), > GFP_KERNEL); >-- >2.0.0 >