From e7b0d26a86943370c04d6833c6edba2a72a6e240 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Thu, 15 Mar 2007 15:51:28 -0400 Subject: [PATCH] sysfs: reinstate exclusion between method calls and attribute unregistration This patch (as869) reinstates the mutual exclusion between sysfs attribute method calls and attribute unregistration. The previously-reported deadlocks have been fixed, and this exclusion is by far the simplest way to avoid races during driver unbinding. The check for orphaned read-buffers has been moved down slightly, so that the remainder of a partially-read buffer will still be available to userspace even after the attribute has been unregistered. Signed-off-by: Alan Stern Cc: Hugh Dickins Cc: Cornelia Huck Cc: Oliver Neukum Signed-off-by: Linus Torvalds --- fs/sysfs/file.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'fs/sysfs/file.c') diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 1bafdf6..fc46333 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -168,12 +168,12 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos) ssize_t retval = 0; down(&buffer->sem); - if (buffer->orphaned) { - retval = -ENODEV; - goto out; - } if (buffer->needs_read_fill) { - if ((retval = fill_read_buffer(file->f_path.dentry,buffer))) + if (buffer->orphaned) + retval = -ENODEV; + else + retval = fill_read_buffer(file->f_path.dentry,buffer); + if (retval) goto out; } pr_debug("%s: count = %zd, ppos = %lld, buf = %s\n", -- cgit v1.1