[SCSI] libsas: introduce sas_work to fix sas_drain_work vs sas_queue_work

When requeuing work to a draining workqueue the last work instance may
not be idle, so sas_queue_work() must not touch work->entry.  Introduce
sas_work with a drain_node list_head to have a private list for
collecting work deferred due to drain collision.

Fixes reports like:
  BUG: unable to handle kernel NULL pointer dereference at           (null)
  IP: [<ffffffff810410d4>] process_one_work+0x2e/0x338

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Dan Williams
2012-03-09 11:00:06 -08:00
committed by James Bottomley
parent f8fc75dc57
commit 22b9153faa
7 changed files with 83 additions and 62 deletions

View File

@@ -94,8 +94,7 @@ void sas_hash_addr(u8 *hashed, const u8 *sas_addr)
void sas_hae_reset(struct work_struct *work)
{
struct sas_ha_event *ev =
container_of(work, struct sas_ha_event, work);
struct sas_ha_event *ev = to_sas_ha_event(work);
struct sas_ha_struct *ha = ev->ha;
clear_bit(HAE_RESET, &ha->pending);
@@ -369,14 +368,14 @@ static void sas_phy_release(struct sas_phy *phy)
static void phy_reset_work(struct work_struct *work)
{
struct sas_phy_data *d = container_of(work, typeof(*d), reset_work);
struct sas_phy_data *d = container_of(work, typeof(*d), reset_work.work);
d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
}
static void phy_enable_work(struct work_struct *work)
{
struct sas_phy_data *d = container_of(work, typeof(*d), enable_work);
struct sas_phy_data *d = container_of(work, typeof(*d), enable_work.work);
d->enable_result = sas_phy_enable(d->phy, d->enable);
}
@@ -389,8 +388,8 @@ static int sas_phy_setup(struct sas_phy *phy)
return -ENOMEM;
mutex_init(&d->event_lock);
INIT_WORK(&d->reset_work, phy_reset_work);
INIT_WORK(&d->enable_work, phy_enable_work);
INIT_SAS_WORK(&d->reset_work, phy_reset_work);
INIT_SAS_WORK(&d->enable_work, phy_enable_work);
d->phy = phy;
phy->hostdata = d;