From: Ravikiran G Thirumalai Date: Tue, 31 Mar 2009 22:19:40 +0000 (-0700) Subject: mm: fix SHM_HUGETLB to work with users in hugetlb_shm_group X-Git-Tag: firefly_0821_release~15147 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=8a0bdec194c21c8fdef840989d0d7b742bb5d4bc;p=firefly-linux-kernel-4.4.55.git mm: fix SHM_HUGETLB to work with users in hugetlb_shm_group Fix hugetlb subsystem so that non root users belonging to hugetlb_shm_group can actually allocate hugetlb backed shm. Currently non root users cannot even map one large page using SHM_HUGETLB when they belong to the gid in /proc/sys/vm/hugetlb_shm_group. This is because allocation size is verified against RLIMIT_MEMLOCK resource limit even if the user belongs to hugetlb_shm_group. This patch 1. Fixes hugetlb subsystem so that users with CAP_IPC_LOCK and users belonging to hugetlb_shm_group don't need to be restricted with RLIMIT_MEMLOCK resource limits 2. This patch also disables mlock based rlimit checking (which will be reinstated and marked deprecated in a subsequent patch). Signed-off-by: Ravikiran Thirumalai Reviewed-by: Mel Gorman Cc: William Lee Irwin III Cc: Adam Litke Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 9b800d97a687..bc56df8ce001 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -943,9 +943,7 @@ static struct vfsmount *hugetlbfs_vfsmount; static int can_do_hugetlb_shm(void) { - return likely(capable(CAP_IPC_LOCK) || - in_group_p(sysctl_hugetlb_shm_group) || - can_do_mlock()); + return capable(CAP_IPC_LOCK) || in_group_p(sysctl_hugetlb_shm_group); } struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag) @@ -963,9 +961,6 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag) if (!can_do_hugetlb_shm()) return ERR_PTR(-EPERM); - if (!user_shm_lock(size, user)) - return ERR_PTR(-ENOMEM); - root = hugetlbfs_vfsmount->mnt_root; quick_string.name = name; quick_string.len = strlen(quick_string.name); @@ -1004,7 +999,6 @@ out_inode: out_dentry: dput(dentry); out_shm_unlock: - user_shm_unlock(size, user); return ERR_PTR(error); }