The patch titled vfs: no "(unreachable)" prefix for SYSVIPC maps in /proc/PID/maps has been added to the -mm tree. Its filename is vfs-no-unreachable-prefix-for-sysvipc-maps-in-proc-pid-maps.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: vfs: no "(unreachable)" prefix for SYSVIPC maps in /proc/PID/maps From: Miklos Szeredi <mszeredi@xxxxxxx> The patch "vfs: fix d_path() for unreachable paths" generally changed d_path() to report unreachable paths with a special prefix. This has an effect on /proc/${PID}/maps as well for memory maps set up with shmem_file_setup() or hugetlb_file_setup(). These functions set up unlinked files under a kernel-private vfsmount. Since this vfsmount is unreachable from userspace, these maps will be reported with the "(unreachable)" prefix. This is undesirable, because it changes the kernel ABI and might break applications for no good reason. Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxx> Acked-by: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx> Cc: Valdis Kletnieks <Valdis.Kletnieks@xxxxxx> Cc: Matthew Wilcox <matthew@xxxxxx> Cc: Andreas Gruenbacher <agruen@xxxxxxx> Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/hugetlbfs/inode.c | 17 +++++++++++++++++ mm/shmem.c | 17 +++++++++++++++++ 2 files changed, 34 insertions(+) diff -puN fs/hugetlbfs/inode.c~vfs-no-unreachable-prefix-for-sysvipc-maps-in-proc-pid-maps fs/hugetlbfs/inode.c --- a/fs/hugetlbfs/inode.c~vfs-no-unreachable-prefix-for-sysvipc-maps-in-proc-pid-maps +++ a/fs/hugetlbfs/inode.c @@ -906,6 +906,21 @@ static struct file_system_type hugetlbfs static struct vfsmount *hugetlbfs_vfsmount; +/* + * Do a special d_dname function so that these are not prefixed by + * "(unreachable)". + */ +static char *hugetlb_unlinked_d_dname(struct dentry *dentry, char *buf, + int buflen) +{ + return dynamic_dname(dentry, buf, buflen, "/%s (deleted)", + dentry->d_name.name); +} + +static struct dentry_operations hugetlb_unlinked_dentry_operations = { + .d_dname = hugetlb_unlinked_d_dname, +}; + static int can_do_hugetlb_shm(void) { return capable(CAP_IPC_LOCK) || in_group_p(sysctl_hugetlb_shm_group); @@ -943,6 +958,8 @@ struct file *hugetlb_file_setup(const ch if (!dentry) goto out_shm_unlock; + dentry->d_op = &hugetlb_unlinked_dentry_operations; + error = -ENOSPC; inode = hugetlbfs_get_inode(root->d_sb, current_fsuid(), current_fsgid(), S_IFREG | S_IRWXUGO, 0); diff -puN mm/shmem.c~vfs-no-unreachable-prefix-for-sysvipc-maps-in-proc-pid-maps mm/shmem.c --- a/mm/shmem.c~vfs-no-unreachable-prefix-for-sysvipc-maps-in-proc-pid-maps +++ a/mm/shmem.c @@ -2604,6 +2604,21 @@ int shmem_unuse(swp_entry_t entry, struc /* common code */ +/* + * Do a special d_dname function so that these are not prefixed by + * "(unreachable)". + */ +static char *shmem_unlinked_d_dname(struct dentry *dentry, char *buf, + int buflen) +{ + return dynamic_dname(dentry, buf, buflen, "/%s (deleted)", + dentry->d_name.name); +} + +static struct dentry_operations shmem_unlinked_dentry_operations = { + .d_dname = shmem_unlinked_d_dname, +}; + /** * shmem_file_setup - get an unlinked file living in tmpfs * @name: name for dentry (to be seen in /proc/<pid>/maps @@ -2636,6 +2651,8 @@ struct file *shmem_file_setup(const char if (!dentry) goto put_memory; + dentry->d_op = &shmem_unlinked_dentry_operations; + error = -ENFILE; file = get_empty_filp(); if (!file) _ Patches currently in -mm which might be from mszeredi@xxxxxxx are linux-next.patch vfs-fix-vfs_rename_dir-for-fs_rename_does_d_move-filesystems.patch fs-remove-unneeded-dcache_unhashed-tricks.patch vfs-fix-d_path-for-unreachable-paths.patch vfs-seq_file-add-helpers-for-data-filling.patch vfs-revert-proc-mounts-to-old-behavior-for-unreachable-mountpoints.patch vfs-no-unreachable-prefix-for-sysvipc-maps-in-proc-pid-maps.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html