Messages in this thread Patch in this message |  | | Date | Fri, 24 Jun 2011 10:48:08 +0900 | | From | "FJCL) 荻野 大輔 " <> | | Subject | [patch] procfs: returns ENOENT on opening the being-removed proc entry |
| |
From: Daisuke Ohino <ogino.daisuke@jp.fujitsu.com>
opening the proc entry may return EINVAL if the entry is being removed, for example open("/proc/bus/pci/XX/YY") during the corresponding device is being hot-removed. The return value is inappropriate and should return ENOENT.
This return value comes from proc_reg_open().
fs/proc/inode.c: ----------------------------------------------------------- static int proc_reg_open(struct inode *inode, struct file *file) { (snip) if (!pde->proc_fops) { spin_unlock(&pde->pde_unload_lock); kfree(pdeo); return -EINVAL; } (snip) -----------------------------------------------------------
pde->proc_fops is NULL iff the proc entry is being removed. It is set by remove_proc_entry().
----------------------------------------------------------- void remove_proc_entry(const char *name, struct proc_dir_entry*parent) { (snip) /* * Stop accepting new callers into module. If you're * dynamically allocating ->proc_fops, save a pointer somewhere. */ de->proc_fops = NULL; (snip) -----------------------------------------------------------
But POSIX says:
----------------------------------------------------------- [EINVAL] The implementation does not support synchronized I/O for this file. -----------------------------------------------------------
Since removing proc entry is apparently not related to synchronized I/O, this function should return ENOENT in this case.
Signed-off-by: Daisuke Ogino <ogino.daisuke@jp.fujitsu.com> --- fs/proc/inode.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 74b48cf..7ed72d6 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -319,7 +319,7 @@ static int proc_reg_open(struct inode *inode, struct file *file) if (!pde->proc_fops) { spin_unlock(&pde->pde_unload_lock); kfree(pdeo); - return -EINVAL; + return -ENOENT; } pde->pde_users++; open = pde->proc_fops->open; -- Since I don't subscribe LKML, please Cc me if you have any comment.
Thanks, Daisuke
|  |