diff options
| author | Takashi Iwai <tiwai@suse.de> | 2021-01-26 09:51:48 +0300 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2021-01-26 09:51:48 +0300 |
| commit | 4f2da3324eaff382ab1c6aaef8c10180b2f4d08c (patch) | |
| tree | 38dab378ba4ad014d83151f020cc1e5979be0d6d /drivers/net/ppp | |
| parent | 6755568ad111394da224c823e8baf31a05a1469c (diff) | |
| parent | 30e88d017fcbeb50c4b07577fe059558361067e7 (diff) | |
| download | linux-4f2da3324eaff382ab1c6aaef8c10180b2f4d08c.tar.xz | |
Merge tag 'tags/isa-void-remove-callback' into for-next
isa: Make the remove callback for isa drivers return void
Link: https://lore.kernel.org/r/20210122092449.426097-1-uwe@kleine-koenig.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'drivers/net/ppp')
| -rw-r--r-- | drivers/net/ppp/ppp_generic.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 09c27f7773f9..d445ecb1d0c7 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -623,6 +623,7 @@ static int ppp_bridge_channels(struct channel *pch, struct channel *pchb) write_unlock_bh(&pch->upl); return -EALREADY; } + refcount_inc(&pchb->file.refcnt); rcu_assign_pointer(pch->bridge, pchb); write_unlock_bh(&pch->upl); @@ -632,19 +633,24 @@ static int ppp_bridge_channels(struct channel *pch, struct channel *pchb) write_unlock_bh(&pchb->upl); goto err_unset; } + refcount_inc(&pch->file.refcnt); rcu_assign_pointer(pchb->bridge, pch); write_unlock_bh(&pchb->upl); - refcount_inc(&pch->file.refcnt); - refcount_inc(&pchb->file.refcnt); - return 0; err_unset: write_lock_bh(&pch->upl); + /* Re-read pch->bridge with upl held in case it was modified concurrently */ + pchb = rcu_dereference_protected(pch->bridge, lockdep_is_held(&pch->upl)); RCU_INIT_POINTER(pch->bridge, NULL); write_unlock_bh(&pch->upl); synchronize_rcu(); + + if (pchb) + if (refcount_dec_and_test(&pchb->file.refcnt)) + ppp_destroy_channel(pchb); + return -EALREADY; } |