Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752998AbZKROyh (ORCPT ); Wed, 18 Nov 2009 09:54:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754335AbZKROxt (ORCPT ); Wed, 18 Nov 2009 09:53:49 -0500 Received: from server1.wserver.cz ([82.113.45.157]:51279 "EHLO server1.wserver.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754775AbZKROwA (ORCPT ); Wed, 18 Nov 2009 09:52:00 -0500 From: Jiri Slaby To: jirislaby@gmail.com Cc: mingo@elte.hu, nhorman@tuxdriver.com, sfr@canb.auug.org.au, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, marcin.slusarz@gmail.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, torvalds@linux-foundation.org, Jiri Slaby , James Morris , Heiko Carstens , Roland Dreier , Sean Hefty , Hal Rosenstock , linux-rdma@vger.kernel.org Subject: [PATCH 11/16] misc: use ACCESS_ONCE for rlimits Date: Wed, 18 Nov 2009 15:51:57 +0100 Message-Id: <1258555922-2064-11-git-send-email-jslaby@novell.com> X-Mailer: git-send-email 1.6.4.2 In-Reply-To: <4B040A03.2020508@gmail.com> References: <4B040A03.2020508@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3272 Lines: 87 Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. Signed-off-by: Jiri Slaby Cc: James Morris Cc: Heiko Carstens Cc: Andrew Morton Cc: Ingo Molnar Cc: Roland Dreier Cc: Sean Hefty Cc: Hal Rosenstock Cc: linux-rdma@vger.kernel.org --- drivers/infiniband/core/umem.c | 3 ++- drivers/infiniband/hw/ipath/ipath_user_pages.c | 4 ++-- ipc/mqueue.c | 4 ++-- ipc/shm.c | 4 ++-- 4 files changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index 6f7c096..90d806b 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -136,7 +136,8 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr, down_write(¤t->mm->mmap_sem); locked = npages + current->mm->locked_vm; - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT; + lock_limit = ACCESS_ONCE(current->signal-> + rlim[RLIMIT_MEMLOCK].rlim_cur) >> PAGE_SHIFT; if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) { ret = -ENOMEM; diff --git a/drivers/infiniband/hw/ipath/ipath_user_pages.c b/drivers/infiniband/hw/ipath/ipath_user_pages.c index 82878e3..f7db156 100644 --- a/drivers/infiniband/hw/ipath/ipath_user_pages.c +++ b/drivers/infiniband/hw/ipath/ipath_user_pages.c @@ -59,8 +59,8 @@ static int __get_user_pages(unsigned long start_page, size_t num_pages, size_t got; int ret; - lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> - PAGE_SHIFT; + lock_limit = ACCESS_ONCE(current->signal-> + rlim[RLIMIT_MEMLOCK].rlim_cur) >> PAGE_SHIFT; if (num_pages > lock_limit) { ret = -ENOMEM; diff --git a/ipc/mqueue.c b/ipc/mqueue.c index ee9d697..d04869f 100644 --- a/ipc/mqueue.c +++ b/ipc/mqueue.c @@ -152,8 +152,8 @@ static struct inode *mqueue_get_inode(struct super_block *sb, spin_lock(&mq_lock); if (u->mq_bytes + mq_bytes < u->mq_bytes || - u->mq_bytes + mq_bytes > - p->signal->rlim[RLIMIT_MSGQUEUE].rlim_cur) { + u->mq_bytes + mq_bytes > ACCESS_ONCE(p->signal-> + rlim[RLIMIT_MSGQUEUE].rlim_cur)) { spin_unlock(&mq_lock); goto out_inode; } diff --git a/ipc/shm.c b/ipc/shm.c index 464694e..99de87c 100644 --- a/ipc/shm.c +++ b/ipc/shm.c @@ -761,8 +761,8 @@ SYSCALL_DEFINE3(shmctl, int, shmid, int, cmd, struct shmid_ds __user *, buf) if (euid != shp->shm_perm.uid && euid != shp->shm_perm.cuid) goto out_unlock; - if (cmd == SHM_LOCK && - !current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur) + if (cmd == SHM_LOCK && !ACCESS_ONCE(current->signal-> + rlim[RLIMIT_MEMLOCK].rlim_cur)) goto out_unlock; } -- 1.6.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/