Commit a160ee69c6a4622ed30c377a978554015e9931cb
Committed by
David S. Miller
David S. Miller
1 parent
5c6ae5b880
Exists in
master
and in
7 other branches
wext: let get_wireless_stats() sleep
A number of drivers (recently including cfg80211-based ones)
assume that all wireless handlers, including statistics, can
sleep and they often also implicitly assume that the rtnl is
held around their invocation. This is almost always true now
except when reading from sysfs:
BUG: sleeping function called from invalid context at kernel/mutex.c:280
in_atomic(): 1, irqs_disabled(): 0, pid: 10450, name: head
2 locks held by head/10450:
#0: (&buffer->mutex){+.+.+.}, at: [<c10ceb99>] sysfs_read_file+0x24/0xf4
#1: (dev_base_lock){++.?..}, at: [<c12844ee>] wireless_show+0x1a/0x4c
Pid: 10450, comm: head Not tainted 2.6.32-rc3 #1
Call Trace:
[<c102301c>] __might_sleep+0xf0/0xf7
[<c1324355>] mutex_lock_nested+0x1a/0x33
[<f8cea53b>] wdev_lock+0xd/0xf [cfg80211]
[<f8cea58f>] cfg80211_wireless_stats+0x45/0x12d [cfg80211]
[<c13118d6>] get_wireless_stats+0x16/0x1c
[<c12844fe>] wireless_show+0x2a/0x4c
Fix this by using the rtnl instead of dev_base_lock.
Reported-by: Miles Lane <miles.lane@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Showing 1 changed file with 2 additions and 2 deletions Side-by-side Diff
net/core/net-sysfs.c
| ... | ... | @@ -366,13 +366,13 @@ |
| 366 | 366 | const struct iw_statistics *iw; |
| 367 | 367 | ssize_t ret = -EINVAL; |
| 368 | 368 | |
| 369 | - read_lock(&dev_base_lock); | |
| 369 | + rtnl_lock(); | |
| 370 | 370 | if (dev_isalive(dev)) { |
| 371 | 371 | iw = get_wireless_stats(dev); |
| 372 | 372 | if (iw) |
| 373 | 373 | ret = (*format)(iw, buf); |
| 374 | 374 | } |
| 375 | - read_unlock(&dev_base_lock); | |
| 375 | + rtnl_unlock(); | |
| 376 | 376 | |
| 377 | 377 | return ret; |
| 378 | 378 | } |