[SCSI] Revert "sg: checking sdp->detached isn't protected when open"
This reverts commit e32c9e6300e3af659cbfe45e90a1e7dcd3572ada.
This is one of four patches that was causing this bug
[ 205.372823] ================================================
[ 205.372901] [ BUG: lock held when returning to user space! ]
[ 205.372979] 3.12.0-rc6-hw-debug-pagealloc+ #67 Not tainted
[ 205.373055] ------------------------------------------------
[ 205.373132] megarc.bin/5283 is leaving the kernel with locks still held!
[ 205.373212] 1 lock held by megarc.bin/5283:
[ 205.373285] #0: (&sdp->o_sem){.+.+..}, at: [<ffffffff8161e650>] sg_open+0x3a0/0x4d0
Cc: Vaughan Cao <vaughan.cao@oracle.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 64df1ab..d4af132 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -295,20 +295,23 @@
if (flags & O_EXCL)
sdp->exclude = 1; /* used by release lock */
+ if (sdp->detached) {
+ retval = -ENODEV;
+ goto sem_out;
+ }
if (sfds_list_empty(sdp)) { /* no existing opens on this device */
sdp->sgdebug = 0;
q = sdp->device->request_queue;
sdp->sg_tablesize = queue_max_segments(q);
}
- sfp = sg_add_sfp(sdp, dev);
- if (!IS_ERR(sfp))
+ if ((sfp = sg_add_sfp(sdp, dev)))
filp->private_data = sfp;
/* retval is already provably zero at this point because of the
* check after retval = scsi_autopm_get_device(sdp->device))
*/
else {
- retval = PTR_ERR(sfp);
-
+ retval = -ENOMEM;
+sem_out:
if (flags & O_EXCL) {
sdp->exclude = 0; /* undo if error */
up_write(&sdp->o_sem);
@@ -2042,7 +2045,7 @@
sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
if (!sfp)
- return ERR_PTR(-ENOMEM);
+ return NULL;
init_waitqueue_head(&sfp->read_wait);
rwlock_init(&sfp->rq_list_lock);
@@ -2057,10 +2060,6 @@
sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
sfp->parentdp = sdp;
write_lock_irqsave(&sg_index_lock, iflags);
- if (sdp->detached) {
- write_unlock_irqrestore(&sg_index_lock, iflags);
- return ERR_PTR(-ENODEV);
- }
list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
write_unlock_irqrestore(&sg_index_lock, iflags);
SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));