[PATCH] habanalabs: Avoid using a non-initialized MMU cache mutex

From: Oded Gabbay
Date: Mon May 13 2019 - 07:34:21 EST


From: Tomer Tayar <ttayar@xxxxxxxxx>

The MMU cache mutex is used in the ASIC hw_init() functions, but it is
initialized only later in hl_mmu_init().
This patch prevents it by moving the initialization to the
device_early_init() function.

Signed-off-by: Tomer Tayar <ttayar@xxxxxxxxx>
Signed-off-by: Oded Gabbay <oded.gabbay@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
drivers/misc/habanalabs/device.c | 2 ++
drivers/misc/habanalabs/mmu.c | 8 +-------
2 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/misc/habanalabs/device.c b/drivers/misc/habanalabs/device.c
index 91a9e47a3482..0b19d3eefb98 100644
--- a/drivers/misc/habanalabs/device.c
+++ b/drivers/misc/habanalabs/device.c
@@ -231,6 +231,7 @@ static int device_early_init(struct hl_device *hdev)

mutex_init(&hdev->fd_open_cnt_lock);
mutex_init(&hdev->send_cpu_message_lock);
+ mutex_init(&hdev->mmu_cache_lock);
INIT_LIST_HEAD(&hdev->hw_queues_mirror_list);
spin_lock_init(&hdev->hw_queues_mirror_lock);
atomic_set(&hdev->in_reset, 0);
@@ -260,6 +261,7 @@ static int device_early_init(struct hl_device *hdev)
*/
static void device_early_fini(struct hl_device *hdev)
{
+ mutex_destroy(&hdev->mmu_cache_lock);
mutex_destroy(&hdev->send_cpu_message_lock);

hl_cb_mgr_fini(hdev, &hdev->kernel_cb_mgr);
diff --git a/drivers/misc/habanalabs/mmu.c b/drivers/misc/habanalabs/mmu.c
index 533d9315b6fb..10aee3141444 100644
--- a/drivers/misc/habanalabs/mmu.c
+++ b/drivers/misc/habanalabs/mmu.c
@@ -404,15 +404,12 @@ int hl_mmu_init(struct hl_device *hdev)

/* MMU H/W init was already done in device hw_init() */

- mutex_init(&hdev->mmu_cache_lock);
-
hdev->mmu_pgt_pool =
gen_pool_create(__ffs(prop->mmu_hop_table_size), -1);

if (!hdev->mmu_pgt_pool) {
dev_err(hdev->dev, "Failed to create page gen pool\n");
- rc = -ENOMEM;
- goto err_pool_create;
+ return -ENOMEM;
}

rc = gen_pool_add(hdev->mmu_pgt_pool, prop->mmu_pgt_addr +
@@ -436,8 +433,6 @@ int hl_mmu_init(struct hl_device *hdev)

err_pool_add:
gen_pool_destroy(hdev->mmu_pgt_pool);
-err_pool_create:
- mutex_destroy(&hdev->mmu_cache_lock);

return rc;
}
@@ -459,7 +454,6 @@ void hl_mmu_fini(struct hl_device *hdev)

kvfree(hdev->mmu_shadow_hop0);
gen_pool_destroy(hdev->mmu_pgt_pool);
- mutex_destroy(&hdev->mmu_cache_lock);

/* MMU H/W fini will be done in device hw_fini() */
}
--
2.17.1