diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index 6dec7cff316f46c377e015e5ad5424339089040e..c167911221e96af131039171ecc7a07e4e34a987 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -112,9 +112,12 @@ _scsih_set_fwfault_debug(const char *val, struct kernel_param *kp)
if (ret)
return ret;
+ /* global ioc spinlock to protect controller list on list operations */
printk(KERN_INFO "setting fwfault_debug(%d)\n", mpt2sas_fwfault_debug);
+ spin_lock(&gioc_lock);
list_for_each_entry(ioc, &mpt2sas_ioc_list, list)
ioc->fwfault_debug = mpt2sas_fwfault_debug;
+ spin_unlock(&gioc_lock);
return 0;
}
@@ -4437,6 +4440,8 @@ mpt2sas_base_free_resources(struct MPT2SAS_ADAPTER *ioc)
dexitprintk(ioc, printk(MPT2SAS_INFO_FMT "%s\n", ioc->name,
__func__));
+ /* synchronizing freeing resource with pci_access_mutex lock */
+ mutex_lock(&ioc->pci_access_mutex);
if (ioc->chip_phys && ioc->chip) {
_base_mask_interrupts(ioc);
ioc->shost_recovery = 1;
@@ -4456,6 +4461,7 @@ mpt2sas_base_free_resources(struct MPT2SAS_ADAPTER *ioc)
pci_disable_pcie_error_reporting(pdev);
pci_disable_device(pdev);
}
+ mutex_unlock(&ioc->pci_access_mutex);
return;
}
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.h b/drivers/scsi/mpt2sas/mpt2sas_base.h
index 78f41aca9598cf7480667df5feda8a0f5dd36da9..97ea360c6920e20f13160b3d96610f84f04ab0b7 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.h
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.h
@@ -817,6 +817,12 @@ typedef void (*MPT2SAS_FLUSH_RUNNING_CMDS)(struct MPT2SAS_ADAPTER *ioc);
* @delayed_tr_list: target reset link list
* @delayed_tr_volume_list: volume target reset link list
* @@temp_sensors_count: flag to carry the number of temperature sensors
+ * @pci_access_mutex: Mutex to synchronize ioctl,sysfs show path and
+ * pci resource handling. PCI resource freeing will lead to free
+ * vital hardware/memory resource, which might be in use by cli/sysfs
+ * path functions resulting in Null pointer reference followed by kernel
+ * crash. To avoid the above race condition we use mutex syncrhonization
+ * which ensures the syncrhonization between cli/sysfs_show path
*/
struct MPT2SAS_ADAPTER {
struct list_head list;
@@ -1033,6 +1039,7 @@ struct MPT2SAS_ADAPTER {
u8 mfg_pg10_hide_flag;
u8 hide_drives;
+ struct mutex pci_access_mutex;
};
typedef u8 (*MPT_CALLBACK)(struct MPT2SAS_ADAPTER *ioc, u16 smid, u8 msix_index,
@@ -1041,6 +1048,17 @@ typedef u8 (*MPT_CALLBACK)(struct MPT2SAS_ADAPTER *ioc, u16 smid, u8 msix_index,
/* base shared API */
extern struct list_head mpt2sas_ioc_list;
+/* spinlock on list operations over IOCs
+ * Case: when multiple warpdrive cards(IOCs) are in use
+ * Each IOC will added to the ioc list stucture on initialization.
+ * Watchdog threads run at regular intervals to check IOC for any
+ * fault conditions which will trigger the dead_ioc thread to
+ * deallocate pci resource, resulting deleting the IOC netry from list,
+ * this deletion need to protected by spinlock to enusre that
+ * ioc removal is syncrhonized, if not synchronized it might lead to
+ * list_del corruption as the ioc list is traversed in cli path
+ */
+extern spinlock_t gioc_lock;
void mpt2sas_base_start_watchdog(struct MPT2SAS_ADAPTER *ioc);
void mpt2sas_base_stop_watchdog(struct MPT2SAS_ADAPTER *ioc);
@@ -1119,7 +1137,6 @@ struct _sas_device *__mpt2sas_get_sdev_by_addr(
struct MPT2SAS_ADAPTER *ioc, u64 sas_address);
void mpt2sas_port_enable_complete(struct MPT2SAS_ADAPTER *ioc);
-
void mpt2sas_scsih_reset_handler(struct MPT2SAS_ADAPTER *ioc, int reset_phase);
/* config shared API */
diff --git a/drivers/scsi/mpt2sas/mpt2sas_ctl.c b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
index 4e509604b5716483c0c52a734b4776a637bb44b2..3694b63bd9931520bb9320fb121a2cfb353a2f35 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_ctl.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_ctl.c
@@ -427,13 +427,16 @@ static int
_ctl_verify_adapter(int ioc_number, struct MPT2SAS_ADAPTER **iocpp)
{
struct MPT2SAS_ADAPTER *ioc;
-
+ /* global ioc lock to protect controller on list operations */
+ spin_lock(&gioc_lock);
list_for_each_entry(ioc, &mpt2sas_ioc_list, list) {
if (ioc->id != ioc_number)
continue;
+ spin_unlock(&gioc_lock);
*iocpp = ioc;
return ioc_number;
}
+ spin_unlock(&gioc_lock);
*iocpp = NULL;
return -1;
}
@@ -522,10 +525,15 @@ _ctl_poll(struct file *filep, poll_table *wait)
poll_wait(filep, &ctl_poll_wait, wait);
+ /* global ioc lock to protect controller on list operations */
+ spin_lock(&gioc_lock);
list_for_each_entry(ioc, &mpt2sas_ioc_list, list) {
- if (ioc->aen_event_read_flag)
+ if (ioc->aen_event_read_flag) {
+ spin_unlock(&gioc_lock);
return POLLIN | POLLRDNORM;
+ }
}
+ spin_unlock(&gioc_lock);
return 0;
}
@@ -2168,16 +2176,23 @@ _ctl_ioctl_main(struct file *file, unsigned int cmd, void __user *arg,
if (_ctl_verify_adapter(ioctl_header.ioc_number, &ioc) == -1 || !ioc)
return -ENODEV;
+ /* pci_access_mutex lock acquired by ioctl path */
+ mutex_lock(&ioc->pci_access_mutex);
if (ioc->shost_recovery || ioc->pci_error_recovery ||
- ioc->is_driver_loading)
- return -EAGAIN;
+ ioc->is_driver_loading || ioc->remove_host) {
+ ret = -EAGAIN;
+ goto out_unlock_pciaccess;
+ }
state = (file->f_flags & O_NONBLOCK) ? NON_BLOCKING : BLOCKING;
if (state == NON_BLOCKING) {
- if (!mutex_trylock(&ioc->ctl_cmds.mutex))
- return -EAGAIN;
+ if (!mutex_trylock(&ioc->ctl_cmds.mutex)) {
+ ret = -EAGAIN;
+ goto out_unlock_pciaccess;
+ }
} else if (mutex_lock_interruptible(&ioc->ctl_cmds.mutex)) {
- return -ERESTARTSYS;
+ ret = -ERESTARTSYS;
+ goto out_unlock_pciaccess;
}
switch (cmd) {
@@ -2258,6 +2273,8 @@ _ctl_ioctl_main(struct file *file, unsigned int cmd, void __user *arg,
}
mutex_unlock(&ioc->ctl_cmds.mutex);
+out_unlock_pciaccess:
+ mutex_unlock(&ioc->pci_access_mutex);
return ret;
}
@@ -2711,6 +2728,12 @@ _ctl_BRM_status_show(struct device *cdev, struct device_attribute *attr,
"warpdrive\n", ioc->name, __func__);
goto out;
}
+ /* pci_access_mutex lock acquired by sysfs show path */
+ mutex_lock(&ioc->pci_access_mutex);
+ if (ioc->pci_error_recovery || ioc->remove_host) {
+ mutex_unlock(&ioc->pci_access_mutex);
+ return 0;
+ }
/* allocate upto GPIOVal 36 entries */
sz = offsetof(Mpi2IOUnitPage3_t, GPIOVal) + (sizeof(u16) * 36);
@@ -2749,6 +2772,7 @@ _ctl_BRM_status_show(struct device *cdev, struct device_attribute *attr,
out:
kfree(io_unit_pg3);
+ mutex_unlock(&ioc->pci_access_mutex);
return rc;
}
static DEVICE_ATTR(BRM_status, S_IRUGO, _ctl_BRM_status_show, NULL);
diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
index c0ff55b0d3ccc886ba896ff1e361c160f0bec5bc..0ad09b2bff9c69d86e11b9416f64e96f19e804bc 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
@@ -79,7 +79,8 @@ static int _scsih_scan_finished(struct Scsi_Host *shost, unsigned long time);
/* global parameters */
LIST_HEAD(mpt2sas_ioc_list);
-
+/* global ioc lock for list operations */
+DEFINE_SPINLOCK(gioc_lock);
/* local parameters */
static u8 scsi_io_cb_idx = -1;
static u8 tm_cb_idx = -1;
@@ -321,8 +322,10 @@ _scsih_set_debug_level(const char *val, struct kernel_param *kp)
return ret;
printk(KERN_INFO "setting logging_level(0x%08x)\n", logging_level);
+ spin_lock(&gioc_lock);
list_for_each_entry(ioc, &mpt2sas_ioc_list, list)
ioc->logging_level = logging_level;
+ spin_unlock(&gioc_lock);
return 0;
}
module_param_call(logging_level, _scsih_set_debug_level, param_get_int,
@@ -8081,7 +8084,9 @@ _scsih_remove(struct pci_dev *pdev)
sas_remove_host(shost);
scsi_remove_host(shost);
mpt2sas_base_detach(ioc);
+ spin_lock(&gioc_lock);
list_del(&ioc->list);
+ spin_unlock(&gioc_lock);
scsi_host_put(shost);
}
@@ -8394,7 +8399,9 @@ _scsih_probe(struct pci_dev *pdev, const struct pci_device_id *id)
ioc = shost_priv(shost);
memset(ioc, 0, sizeof(struct MPT2SAS_ADAPTER));
INIT_LIST_HEAD(&ioc->list);
+ spin_lock(&gioc_lock);
list_add_tail(&ioc->list, &mpt2sas_ioc_list);
+ spin_unlock(&gioc_lock);
ioc->shost = shost;
ioc->id = mpt_ids++;
sprintf(ioc->name, "%s%d", MPT2SAS_DRIVER_NAME, ioc->id);
@@ -8419,6 +8426,8 @@ _scsih_probe(struct pci_dev *pdev, const struct pci_device_id *id)
ioc->schedule_dead_ioc_flush_running_cmds = &_scsih_flush_running_cmds;
/* misc semaphores and spin locks */
mutex_init(&ioc->reset_in_progress_mutex);
+ /* initializing pci_access_mutex lock */
+ mutex_init(&ioc->pci_access_mutex);
spin_lock_init(&ioc->ioc_reset_in_progress_lock);
spin_lock_init(&ioc->scsi_lookup_lock);
spin_lock_init(&ioc->sas_device_lock);
@@ -8521,7 +8530,9 @@ _scsih_probe(struct pci_dev *pdev, const struct pci_device_id *id)
out_attach_fail:
destroy_workqueue(ioc->firmware_event_thread);
out_thread_fail:
+ spin_lock(&gioc_lock);
list_del(&ioc->list);
+ spin_unlock(&gioc_lock);
scsi_host_put(shost);
return rv;
}