--- /dev/null
+From a59db67656021fa212e9b95a583f13c34eb67cd9 Mon Sep 17 00:00:00 2001
+From: Joe Thornber <ejt@redhat.com>
+Date: Fri, 23 Jan 2015 10:16:16 +0000
+Subject: dm cache: fix problematic dual use of a single migration count variable
+
+From: Joe Thornber <ejt@redhat.com>
+
+commit a59db67656021fa212e9b95a583f13c34eb67cd9 upstream.
+
+Introduce a new variable to count the number of allocated migration
+structures. The existing variable cache->nr_migrations became
+overloaded. It was used to:
+
+ i) track of the number of migrations in flight for the purposes of
+ quiescing during suspend.
+
+ ii) to estimate the amount of background IO occuring.
+
+Recent discard changes meant that REQ_DISCARD bios are processed with
+a migration. Discards are not background IO so nr_migrations was not
+incremented. However this could cause quiescing to complete early.
+
+(i) is now handled with a new variable cache->nr_allocated_migrations.
+cache->nr_migrations has been renamed cache->nr_io_migrations.
+cleanup_migration() is now called free_io_migration(), since it
+decrements that variable.
+
+Also, remove the unused cache->next_migration variable that got replaced
+with with prealloc_structs a while ago.
+
+Signed-off-by: Joe Thornber <ejt@redhat.com>
+Signed-off-by: Mike Snitzer <snitzer@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/dm-cache-target.c | 89 ++++++++++++++++++++++++-------------------
+ 1 file changed, 50 insertions(+), 39 deletions(-)
+
+--- a/drivers/md/dm-cache-target.c
++++ b/drivers/md/dm-cache-target.c
+@@ -222,7 +222,13 @@ struct cache {
+ struct list_head need_commit_migrations;
+ sector_t migration_threshold;
+ wait_queue_head_t migration_wait;
+- atomic_t nr_migrations;
++ atomic_t nr_allocated_migrations;
++
++ /*
++ * The number of in flight migrations that are performing
++ * background io. eg, promotion, writeback.
++ */
++ atomic_t nr_io_migrations;
+
+ wait_queue_head_t quiescing_wait;
+ atomic_t quiescing;
+@@ -259,7 +265,6 @@ struct cache {
+ struct dm_deferred_set *all_io_ds;
+
+ mempool_t *migration_pool;
+- struct dm_cache_migration *next_migration;
+
+ struct dm_cache_policy *policy;
+ unsigned policy_nr_args;
+@@ -350,10 +355,31 @@ static void free_prison_cell(struct cach
+ dm_bio_prison_free_cell(cache->prison, cell);
+ }
+
++static struct dm_cache_migration *alloc_migration(struct cache *cache)
++{
++ struct dm_cache_migration *mg;
++
++ mg = mempool_alloc(cache->migration_pool, GFP_NOWAIT);
++ if (mg) {
++ mg->cache = cache;
++ atomic_inc(&mg->cache->nr_allocated_migrations);
++ }
++
++ return mg;
++}
++
++static void free_migration(struct dm_cache_migration *mg)
++{
++ if (atomic_dec_and_test(&mg->cache->nr_allocated_migrations))
++ wake_up(&mg->cache->migration_wait);
++
++ mempool_free(mg, mg->cache->migration_pool);
++}
++
+ static int prealloc_data_structs(struct cache *cache, struct prealloc *p)
+ {
+ if (!p->mg) {
+- p->mg = mempool_alloc(cache->migration_pool, GFP_NOWAIT);
++ p->mg = alloc_migration(cache);
+ if (!p->mg)
+ return -ENOMEM;
+ }
+@@ -382,7 +408,7 @@ static void prealloc_free_structs(struct
+ free_prison_cell(cache, p->cell1);
+
+ if (p->mg)
+- mempool_free(p->mg, cache->migration_pool);
++ free_migration(p->mg);
+ }
+
+ static struct dm_cache_migration *prealloc_get_migration(struct prealloc *p)
+@@ -812,24 +838,14 @@ static void remap_to_origin_then_cache(s
+ * Migration covers moving data from the origin device to the cache, or
+ * vice versa.
+ *--------------------------------------------------------------*/
+-static void free_migration(struct dm_cache_migration *mg)
+-{
+- mempool_free(mg, mg->cache->migration_pool);
+-}
+-
+-static void inc_nr_migrations(struct cache *cache)
++static void inc_io_migrations(struct cache *cache)
+ {
+- atomic_inc(&cache->nr_migrations);
++ atomic_inc(&cache->nr_io_migrations);
+ }
+
+-static void dec_nr_migrations(struct cache *cache)
++static void dec_io_migrations(struct cache *cache)
+ {
+- atomic_dec(&cache->nr_migrations);
+-
+- /*
+- * Wake the worker in case we're suspending the target.
+- */
+- wake_up(&cache->migration_wait);
++ atomic_dec(&cache->nr_io_migrations);
+ }
+
+ static void __cell_defer(struct cache *cache, struct dm_bio_prison_cell *cell,
+@@ -852,11 +868,10 @@ static void cell_defer(struct cache *cac
+ wake_worker(cache);
+ }
+
+-static void cleanup_migration(struct dm_cache_migration *mg)
++static void free_io_migration(struct dm_cache_migration *mg)
+ {
+- struct cache *cache = mg->cache;
++ dec_io_migrations(mg->cache);
+ free_migration(mg);
+- dec_nr_migrations(cache);
+ }
+
+ static void migration_failure(struct dm_cache_migration *mg)
+@@ -881,7 +896,7 @@ static void migration_failure(struct dm_
+ cell_defer(cache, mg->new_ocell, true);
+ }
+
+- cleanup_migration(mg);
++ free_io_migration(mg);
+ }
+
+ static void migration_success_pre_commit(struct dm_cache_migration *mg)
+@@ -892,7 +907,7 @@ static void migration_success_pre_commit
+ if (mg->writeback) {
+ clear_dirty(cache, mg->old_oblock, mg->cblock);
+ cell_defer(cache, mg->old_ocell, false);
+- cleanup_migration(mg);
++ free_io_migration(mg);
+ return;
+
+ } else if (mg->demote) {
+@@ -902,14 +917,14 @@ static void migration_success_pre_commit
+ mg->old_oblock);
+ if (mg->promote)
+ cell_defer(cache, mg->new_ocell, true);
+- cleanup_migration(mg);
++ free_io_migration(mg);
+ return;
+ }
+ } else {
+ if (dm_cache_insert_mapping(cache->cmd, mg->cblock, mg->new_oblock)) {
+ DMWARN_LIMIT("promotion failed; couldn't update on disk metadata");
+ policy_remove_mapping(cache->policy, mg->new_oblock);
+- cleanup_migration(mg);
++ free_io_migration(mg);
+ return;
+ }
+ }
+@@ -942,7 +957,7 @@ static void migration_success_post_commi
+ } else {
+ if (mg->invalidate)
+ policy_remove_mapping(cache->policy, mg->old_oblock);
+- cleanup_migration(mg);
++ free_io_migration(mg);
+ }
+
+ } else {
+@@ -957,7 +972,7 @@ static void migration_success_post_commi
+ bio_endio(mg->new_ocell->holder, 0);
+ cell_defer(cache, mg->new_ocell, false);
+ }
+- cleanup_migration(mg);
++ free_io_migration(mg);
+ }
+ }
+
+@@ -1169,7 +1184,7 @@ static void promote(struct cache *cache,
+ mg->new_ocell = cell;
+ mg->start_jiffies = jiffies;
+
+- inc_nr_migrations(cache);
++ inc_io_migrations(cache);
+ quiesce_migration(mg);
+ }
+
+@@ -1192,7 +1207,7 @@ static void writeback(struct cache *cach
+ mg->new_ocell = NULL;
+ mg->start_jiffies = jiffies;
+
+- inc_nr_migrations(cache);
++ inc_io_migrations(cache);
+ quiesce_migration(mg);
+ }
+
+@@ -1218,7 +1233,7 @@ static void demote_then_promote(struct c
+ mg->new_ocell = new_ocell;
+ mg->start_jiffies = jiffies;
+
+- inc_nr_migrations(cache);
++ inc_io_migrations(cache);
+ quiesce_migration(mg);
+ }
+
+@@ -1245,7 +1260,7 @@ static void invalidate(struct cache *cac
+ mg->new_ocell = NULL;
+ mg->start_jiffies = jiffies;
+
+- inc_nr_migrations(cache);
++ inc_io_migrations(cache);
+ quiesce_migration(mg);
+ }
+
+@@ -1306,7 +1321,7 @@ static void process_discard_bio(struct c
+
+ static bool spare_migration_bandwidth(struct cache *cache)
+ {
+- sector_t current_volume = (atomic_read(&cache->nr_migrations) + 1) *
++ sector_t current_volume = (atomic_read(&cache->nr_io_migrations) + 1) *
+ cache->sectors_per_block;
+ return current_volume < cache->migration_threshold;
+ }
+@@ -1661,7 +1676,7 @@ static void stop_quiescing(struct cache
+
+ static void wait_for_migrations(struct cache *cache)
+ {
+- wait_event(cache->migration_wait, !atomic_read(&cache->nr_migrations));
++ wait_event(cache->migration_wait, !atomic_read(&cache->nr_allocated_migrations));
+ }
+
+ static void stop_worker(struct cache *cache)
+@@ -1772,9 +1787,6 @@ static void destroy(struct cache *cache)
+ {
+ unsigned i;
+
+- if (cache->next_migration)
+- mempool_free(cache->next_migration, cache->migration_pool);
+-
+ if (cache->migration_pool)
+ mempool_destroy(cache->migration_pool);
+
+@@ -2282,7 +2294,8 @@ static int cache_create(struct cache_arg
+ INIT_LIST_HEAD(&cache->quiesced_migrations);
+ INIT_LIST_HEAD(&cache->completed_migrations);
+ INIT_LIST_HEAD(&cache->need_commit_migrations);
+- atomic_set(&cache->nr_migrations, 0);
++ atomic_set(&cache->nr_allocated_migrations, 0);
++ atomic_set(&cache->nr_io_migrations, 0);
+ init_waitqueue_head(&cache->migration_wait);
+
+ init_waitqueue_head(&cache->quiescing_wait);
+@@ -2342,8 +2355,6 @@ static int cache_create(struct cache_arg
+ goto bad;
+ }
+
+- cache->next_migration = NULL;
+-
+ cache->need_tick_bio = true;
+ cache->sized = false;
+ cache->invalidate = false;
--- /dev/null
+From 9b1cc9f251affdd27f29fe46d0989ba76c33faf6 Mon Sep 17 00:00:00 2001
+From: Joe Thornber <ejt@redhat.com>
+Date: Fri, 23 Jan 2015 10:00:07 +0000
+Subject: dm cache: share cache-metadata object across inactive and active DM tables
+
+From: Joe Thornber <ejt@redhat.com>
+
+commit 9b1cc9f251affdd27f29fe46d0989ba76c33faf6 upstream.
+
+If a DM table is reloaded with an inactive table when the device is not
+suspended (normal procedure for LVM2), then there will be two dm-bufio
+objects that can diverge. This can lead to a situation where the
+inactive table uses bufio to read metadata at the same time the active
+table writes metadata -- resulting in the inactive table having stale
+metadata buffers once it is promoted to the active table slot.
+
+Fix this by using reference counting and a global list of cache metadata
+objects to ensure there is only one metadata object per metadata device.
+
+Signed-off-by: Joe Thornber <ejt@redhat.com>
+Signed-off-by: Mike Snitzer <snitzer@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/md/dm-cache-metadata.c | 101 ++++++++++++++++++++++++++++++++++++++---
+ 1 file changed, 95 insertions(+), 6 deletions(-)
+
+--- a/drivers/md/dm-cache-metadata.c
++++ b/drivers/md/dm-cache-metadata.c
+@@ -94,6 +94,9 @@ struct cache_disk_superblock {
+ } __packed;
+
+ struct dm_cache_metadata {
++ atomic_t ref_count;
++ struct list_head list;
++
+ struct block_device *bdev;
+ struct dm_block_manager *bm;
+ struct dm_space_map *metadata_sm;
+@@ -669,10 +672,10 @@ static void unpack_value(__le64 value_le
+
+ /*----------------------------------------------------------------*/
+
+-struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev,
+- sector_t data_block_size,
+- bool may_format_device,
+- size_t policy_hint_size)
++static struct dm_cache_metadata *metadata_open(struct block_device *bdev,
++ sector_t data_block_size,
++ bool may_format_device,
++ size_t policy_hint_size)
+ {
+ int r;
+ struct dm_cache_metadata *cmd;
+@@ -683,6 +686,7 @@ struct dm_cache_metadata *dm_cache_metad
+ return NULL;
+ }
+
++ atomic_set(&cmd->ref_count, 1);
+ init_rwsem(&cmd->root_lock);
+ cmd->bdev = bdev;
+ cmd->data_block_size = data_block_size;
+@@ -705,10 +709,95 @@ struct dm_cache_metadata *dm_cache_metad
+ return cmd;
+ }
+
++/*
++ * We keep a little list of ref counted metadata objects to prevent two
++ * different target instances creating separate bufio instances. This is
++ * an issue if a table is reloaded before the suspend.
++ */
++static DEFINE_MUTEX(table_lock);
++static LIST_HEAD(table);
++
++static struct dm_cache_metadata *lookup(struct block_device *bdev)
++{
++ struct dm_cache_metadata *cmd;
++
++ list_for_each_entry(cmd, &table, list)
++ if (cmd->bdev == bdev) {
++ atomic_inc(&cmd->ref_count);
++ return cmd;
++ }
++
++ return NULL;
++}
++
++static struct dm_cache_metadata *lookup_or_open(struct block_device *bdev,
++ sector_t data_block_size,
++ bool may_format_device,
++ size_t policy_hint_size)
++{
++ struct dm_cache_metadata *cmd, *cmd2;
++
++ mutex_lock(&table_lock);
++ cmd = lookup(bdev);
++ mutex_unlock(&table_lock);
++
++ if (cmd)
++ return cmd;
++
++ cmd = metadata_open(bdev, data_block_size, may_format_device, policy_hint_size);
++ if (cmd) {
++ mutex_lock(&table_lock);
++ cmd2 = lookup(bdev);
++ if (cmd2) {
++ mutex_unlock(&table_lock);
++ __destroy_persistent_data_objects(cmd);
++ kfree(cmd);
++ return cmd2;
++ }
++ list_add(&cmd->list, &table);
++ mutex_unlock(&table_lock);
++ }
++
++ return cmd;
++}
++
++static bool same_params(struct dm_cache_metadata *cmd, sector_t data_block_size)
++{
++ if (cmd->data_block_size != data_block_size) {
++ DMERR("data_block_size (%llu) different from that in metadata (%llu)\n",
++ (unsigned long long) data_block_size,
++ (unsigned long long) cmd->data_block_size);
++ return false;
++ }
++
++ return true;
++}
++
++struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev,
++ sector_t data_block_size,
++ bool may_format_device,
++ size_t policy_hint_size)
++{
++ struct dm_cache_metadata *cmd = lookup_or_open(bdev, data_block_size,
++ may_format_device, policy_hint_size);
++ if (cmd && !same_params(cmd, data_block_size)) {
++ dm_cache_metadata_close(cmd);
++ return NULL;
++ }
++
++ return cmd;
++}
++
+ void dm_cache_metadata_close(struct dm_cache_metadata *cmd)
+ {
+- __destroy_persistent_data_objects(cmd);
+- kfree(cmd);
++ if (atomic_dec_and_test(&cmd->ref_count)) {
++ mutex_lock(&table_lock);
++ list_del(&cmd->list);
++ mutex_unlock(&table_lock);
++
++ __destroy_persistent_data_objects(cmd);
++ kfree(cmd);
++ }
+ }
+
+ /*
--- /dev/null
+From 6cdb08172bc89f0a39e1643c5e7eab362692fd1b Mon Sep 17 00:00:00 2001
+From: Brian King <brking@linux.vnet.ibm.com>
+Date: Thu, 30 Oct 2014 17:27:10 -0500
+Subject: ipr: wait for aborted command responses
+
+From: Brian King <brking@linux.vnet.ibm.com>
+
+commit 6cdb08172bc89f0a39e1643c5e7eab362692fd1b upstream.
+
+Fixes a race condition in abort handling that was injected
+when multiple interrupt support was added. When only a single
+interrupt is present, the adapter guarantees it will send
+responses for aborted commands prior to the response for the
+abort command itself. With multiple interrupts, these responses
+generally come back on different interrupts, so we need to
+ensure the abort thread waits until the aborted command is
+complete so we don't perform a double completion. This race
+condition was being hit frequently in environments which
+were triggering command timeouts, which was resulting in
+a double completion causing a kernel oops.
+
+Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
+Reviewed-by: Wendy Xiong <wenxiong@linux.vnet.ibm.com>
+Tested-by: Wendy Xiong <wenxiong@linux.vnet.ibm.com>
+Signed-off-by: Christoph Hellwig <hch@lst.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/scsi/ipr.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++++
+ drivers/scsi/ipr.h | 1
+ 2 files changed, 93 insertions(+)
+
+--- a/drivers/scsi/ipr.c
++++ b/drivers/scsi/ipr.c
+@@ -683,6 +683,7 @@ static void ipr_init_ipr_cmnd(struct ipr
+ ipr_reinit_ipr_cmnd(ipr_cmd);
+ ipr_cmd->u.scratch = 0;
+ ipr_cmd->sibling = NULL;
++ ipr_cmd->eh_comp = NULL;
+ ipr_cmd->fast_done = fast_done;
+ init_timer(&ipr_cmd->timer);
+ }
+@@ -848,6 +849,8 @@ static void ipr_scsi_eh_done(struct ipr_
+
+ scsi_dma_unmap(ipr_cmd->scsi_cmd);
+ scsi_cmd->scsi_done(scsi_cmd);
++ if (ipr_cmd->eh_comp)
++ complete(ipr_cmd->eh_comp);
+ list_add_tail(&ipr_cmd->queue, &ipr_cmd->hrrq->hrrq_free_q);
+ }
+
+@@ -4805,6 +4808,84 @@ static int ipr_slave_alloc(struct scsi_d
+ return rc;
+ }
+
++/**
++ * ipr_match_lun - Match function for specified LUN
++ * @ipr_cmd: ipr command struct
++ * @device: device to match (sdev)
++ *
++ * Returns:
++ * 1 if command matches sdev / 0 if command does not match sdev
++ **/
++static int ipr_match_lun(struct ipr_cmnd *ipr_cmd, void *device)
++{
++ if (ipr_cmd->scsi_cmd && ipr_cmd->scsi_cmd->device == device)
++ return 1;
++ return 0;
++}
++
++/**
++ * ipr_wait_for_ops - Wait for matching commands to complete
++ * @ipr_cmd: ipr command struct
++ * @device: device to match (sdev)
++ * @match: match function to use
++ *
++ * Returns:
++ * SUCCESS / FAILED
++ **/
++static int ipr_wait_for_ops(struct ipr_ioa_cfg *ioa_cfg, void *device,
++ int (*match)(struct ipr_cmnd *, void *))
++{
++ struct ipr_cmnd *ipr_cmd;
++ int wait;
++ unsigned long flags;
++ struct ipr_hrr_queue *hrrq;
++ signed long timeout = IPR_ABORT_TASK_TIMEOUT;
++ DECLARE_COMPLETION_ONSTACK(comp);
++
++ ENTER;
++ do {
++ wait = 0;
++
++ for_each_hrrq(hrrq, ioa_cfg) {
++ spin_lock_irqsave(hrrq->lock, flags);
++ list_for_each_entry(ipr_cmd, &hrrq->hrrq_pending_q, queue) {
++ if (match(ipr_cmd, device)) {
++ ipr_cmd->eh_comp = ∁
++ wait++;
++ }
++ }
++ spin_unlock_irqrestore(hrrq->lock, flags);
++ }
++
++ if (wait) {
++ timeout = wait_for_completion_timeout(&comp, timeout);
++
++ if (!timeout) {
++ wait = 0;
++
++ for_each_hrrq(hrrq, ioa_cfg) {
++ spin_lock_irqsave(hrrq->lock, flags);
++ list_for_each_entry(ipr_cmd, &hrrq->hrrq_pending_q, queue) {
++ if (match(ipr_cmd, device)) {
++ ipr_cmd->eh_comp = NULL;
++ wait++;
++ }
++ }
++ spin_unlock_irqrestore(hrrq->lock, flags);
++ }
++
++ if (wait)
++ dev_err(&ioa_cfg->pdev->dev, "Timed out waiting for aborted commands\n");
++ LEAVE;
++ return wait ? FAILED : SUCCESS;
++ }
++ }
++ } while (wait);
++
++ LEAVE;
++ return SUCCESS;
++}
++
+ static int ipr_eh_host_reset(struct scsi_cmnd *cmd)
+ {
+ struct ipr_ioa_cfg *ioa_cfg;
+@@ -5023,11 +5104,17 @@ static int __ipr_eh_dev_reset(struct scs
+ static int ipr_eh_dev_reset(struct scsi_cmnd *cmd)
+ {
+ int rc;
++ struct ipr_ioa_cfg *ioa_cfg;
++
++ ioa_cfg = (struct ipr_ioa_cfg *) cmd->device->host->hostdata;
+
+ spin_lock_irq(cmd->device->host->host_lock);
+ rc = __ipr_eh_dev_reset(cmd);
+ spin_unlock_irq(cmd->device->host->host_lock);
+
++ if (rc == SUCCESS)
++ rc = ipr_wait_for_ops(ioa_cfg, cmd->device, ipr_match_lun);
++
+ return rc;
+ }
+
+@@ -5205,13 +5292,18 @@ static int ipr_eh_abort(struct scsi_cmnd
+ {
+ unsigned long flags;
+ int rc;
++ struct ipr_ioa_cfg *ioa_cfg;
+
+ ENTER;
+
++ ioa_cfg = (struct ipr_ioa_cfg *) scsi_cmd->device->host->hostdata;
++
+ spin_lock_irqsave(scsi_cmd->device->host->host_lock, flags);
+ rc = ipr_cancel_op(scsi_cmd);
+ spin_unlock_irqrestore(scsi_cmd->device->host->host_lock, flags);
+
++ if (rc == SUCCESS)
++ rc = ipr_wait_for_ops(ioa_cfg, scsi_cmd->device, ipr_match_lun);
+ LEAVE;
+ return rc;
+ }
+--- a/drivers/scsi/ipr.h
++++ b/drivers/scsi/ipr.h
+@@ -1585,6 +1585,7 @@ struct ipr_cmnd {
+ struct scsi_device *sdev;
+ } u;
+
++ struct completion *eh_comp;
+ struct ipr_hrr_queue *hrrq;
+ struct ipr_ioa_cfg *ioa_cfg;
+ };
--- /dev/null
+From f331a859e0ee5a898c1f47596eddad4c4f02d657 Mon Sep 17 00:00:00 2001
+From: Alex Williamson <alex.williamson@redhat.com>
+Date: Thu, 15 Jan 2015 18:16:04 -0600
+Subject: PCI: Add flag for devices where we can't use bus reset
+
+From: Alex Williamson <alex.williamson@redhat.com>
+
+commit f331a859e0ee5a898c1f47596eddad4c4f02d657 upstream.
+
+Enable a mechanism for devices to quirk that they do not behave when
+doing a PCI bus reset. We require a modest level of spec compliant
+behavior in order to do a reset, for instance the device should come
+out of reset without throwing errors and PCI config space should be
+accessible after reset. This is too much to ask for some devices.
+
+Link: http://lkml.kernel.org/r/20140923210318.498dacbd@dualc.maya.org
+Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
+Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/pci/pci.c | 40 ++++++++++++++++++++++++++++++++++++----
+ include/linux/pci.h | 2 ++
+ 2 files changed, 38 insertions(+), 4 deletions(-)
+
+--- a/drivers/pci/pci.c
++++ b/drivers/pci/pci.c
+@@ -3187,7 +3187,8 @@ static int pci_parent_bus_reset(struct p
+ {
+ struct pci_dev *pdev;
+
+- if (pci_is_root_bus(dev->bus) || dev->subordinate || !dev->bus->self)
++ if (pci_is_root_bus(dev->bus) || dev->subordinate ||
++ !dev->bus->self || dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
+ return -ENOTTY;
+
+ list_for_each_entry(pdev, &dev->bus->devices, bus_list)
+@@ -3221,7 +3222,8 @@ static int pci_dev_reset_slot_function(s
+ {
+ struct pci_dev *pdev;
+
+- if (dev->subordinate || !dev->slot)
++ if (dev->subordinate || !dev->slot ||
++ dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
+ return -ENOTTY;
+
+ list_for_each_entry(pdev, &dev->bus->devices, bus_list)
+@@ -3452,6 +3454,20 @@ int pci_try_reset_function(struct pci_de
+ }
+ EXPORT_SYMBOL_GPL(pci_try_reset_function);
+
++/* Do any devices on or below this bus prevent a bus reset? */
++static bool pci_bus_resetable(struct pci_bus *bus)
++{
++ struct pci_dev *dev;
++
++ list_for_each_entry(dev, &bus->devices, bus_list) {
++ if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
++ (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
++ return false;
++ }
++
++ return true;
++}
++
+ /* Lock devices from the top of the tree down */
+ static void pci_bus_lock(struct pci_bus *bus)
+ {
+@@ -3502,6 +3518,22 @@ unlock:
+ return 0;
+ }
+
++/* Do any devices on or below this slot prevent a bus reset? */
++static bool pci_slot_resetable(struct pci_slot *slot)
++{
++ struct pci_dev *dev;
++
++ list_for_each_entry(dev, &slot->bus->devices, bus_list) {
++ if (!dev->slot || dev->slot != slot)
++ continue;
++ if (dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET ||
++ (dev->subordinate && !pci_bus_resetable(dev->subordinate)))
++ return false;
++ }
++
++ return true;
++}
++
+ /* Lock devices from the top of the tree down */
+ static void pci_slot_lock(struct pci_slot *slot)
+ {
+@@ -3623,7 +3655,7 @@ static int pci_slot_reset(struct pci_slo
+ {
+ int rc;
+
+- if (!slot)
++ if (!slot || !pci_slot_resetable(slot))
+ return -ENOTTY;
+
+ if (!probe)
+@@ -3715,7 +3747,7 @@ EXPORT_SYMBOL_GPL(pci_try_reset_slot);
+
+ static int pci_bus_reset(struct pci_bus *bus, int probe)
+ {
+- if (!bus->self)
++ if (!bus->self || !pci_bus_resetable(bus))
+ return -ENOTTY;
+
+ if (probe)
+--- a/include/linux/pci.h
++++ b/include/linux/pci.h
+@@ -170,6 +170,8 @@ enum pci_dev_flags {
+ PCI_DEV_FLAGS_NO_D3 = (__force pci_dev_flags_t) 2,
+ /* Provide indication device is assigned by a Virtual Machine Manager */
+ PCI_DEV_FLAGS_ASSIGNED = (__force pci_dev_flags_t) 4,
++ /* Do not use bus resets for device */
++ PCI_DEV_FLAGS_NO_BUS_RESET = (__force pci_dev_flags_t) (1 << 6),
+ };
+
+ enum pci_irq_reroute_variant {
--- /dev/null
+From c3e59ee4e76686b0c84ca8faa1011d10cd4ca1b8 Mon Sep 17 00:00:00 2001
+From: Alex Williamson <alex.williamson@redhat.com>
+Date: Thu, 15 Jan 2015 18:17:12 -0600
+Subject: PCI: Mark Atheros AR93xx to avoid bus reset
+
+From: Alex Williamson <alex.williamson@redhat.com>
+
+commit c3e59ee4e76686b0c84ca8faa1011d10cd4ca1b8 upstream.
+
+Reports against the TL-WDN4800 card indicate that PCI bus reset of this
+Atheros device cause system lock-ups and resets. I've also been able to
+confirm this behavior on multiple systems. The device never returns from
+reset and attempts to access config space of the device after reset result
+in hangs. Blacklist bus reset for the device to avoid this issue.
+
+[bhelgaas: This regression appeared in v3.14. Andreas bisected it to
+425c1b223dac ("PCI: Add Virtual Channel to save/restore support"), but we
+don't understand the mechanism by which that commit affects the reset
+path.]
+
+[bhelgaas: changelog, references]
+Link: http://lkml.kernel.org/r/20140923210318.498dacbd@dualc.maya.org
+Reported-by: Andreas Hartmann <andihartmann@freenet.de>
+Tested-by: Andreas Hartmann <andihartmann@freenet.de>
+Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
+Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/pci/quirks.c | 14 ++++++++++++++
+ 1 file changed, 14 insertions(+)
+
+--- a/drivers/pci/quirks.c
++++ b/drivers/pci/quirks.c
+@@ -3008,6 +3008,20 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_C
+ DECLARE_PCI_FIXUP_HEADER(0x1814, 0x0601, /* Ralink RT2800 802.11n PCI */
+ quirk_broken_intx_masking);
+
++static void quirk_no_bus_reset(struct pci_dev *dev)
++{
++ dev->dev_flags |= PCI_DEV_FLAGS_NO_BUS_RESET;
++}
++
++/*
++ * Atheros AR93xx chips do not behave after a bus reset. The device will
++ * throw a Link Down error on AER-capable systems and regardless of AER,
++ * config space of the device is never accessible again and typically
++ * causes the system to hang or reset when access is attempted.
++ * http://www.spinics.net/lists/linux-pci/msg34797.html
++ */
++DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0030, quirk_no_bus_reset);
++
+ static void pci_do_fixups(struct pci_dev *dev, struct pci_fixup *f,
+ struct pci_fixup *end)
+ {
drm-radeon-add-a-dpm-quirk-list.patch
drm-radeon-add-si-dpm-quirk-list.patch
drm-radeon-use-rv515_ring_start-on-r5xx.patch
+pci-add-flag-for-devices-where-we-can-t-use-bus-reset.patch
+pci-mark-atheros-ar93xx-to-avoid-bus-reset.patch
+ipr-wait-for-aborted-command-responses.patch
+dm-cache-share-cache-metadata-object-across-inactive-and-active-dm-tables.patch
+dm-cache-fix-problematic-dual-use-of-a-single-migration-count-variable.patch
projects / thirdparty / kernel / stable-queue.git / commitdiff
