habanalabs/gaudi: scrub all memory upon closing FD
In cases of multi-tenants, administrators may want to prevent data
leakage between users running on the same device one after another.
To do that the driver can scrub the internal memory (both SRAM and
DRAM) after a user finish to use the memory.
Because in GAUDI the driver allows only one application to use the
device at a time, it can scrub the memory when user app close FD.
In future devices where we have MMU on the DRAM, we can scrub the DRAM
memory with a finer granularity (page granularity) when the user
allocates the memory.
This feature is not supported in Goya.
To allow users that want to debug their applications, we add a kernel
module parameter to load the driver with this feature disabled.
Signed-off-by: farah kassabri <fkassabri@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
diff --git a/drivers/misc/habanalabs/common/habanalabs_drv.c b/drivers/misc/habanalabs/common/habanalabs_drv.c
index 4c49d6c..20458bd 100644
--- a/drivers/misc/habanalabs/common/habanalabs_drv.c
+++ b/drivers/misc/habanalabs/common/habanalabs_drv.c
@@ -29,6 +29,7 @@ static DEFINE_MUTEX(hl_devs_idr_lock);
static int timeout_locked = 5;
static int reset_on_lockup = 1;
+static int memory_scrub = 1;
module_param(timeout_locked, int, 0444);
MODULE_PARM_DESC(timeout_locked,
@@ -38,6 +39,10 @@ module_param(reset_on_lockup, int, 0444);
MODULE_PARM_DESC(reset_on_lockup,
"Do device reset on lockup (0 = no, 1 = yes, default yes)");
+module_param(memory_scrub, int, 0444);
+MODULE_PARM_DESC(memory_scrub,
+ "Scrub device memory in various states (0 = no, 1 = yes, default yes)");
+
#define PCI_VENDOR_ID_HABANALABS 0x1da3
#define PCI_IDS_GOYA 0x0001
@@ -284,6 +289,7 @@ int create_hdev(struct hl_device **dev, struct pci_dev *pdev,
hdev->major = hl_major;
hdev->reset_on_lockup = reset_on_lockup;
+ hdev->memory_scrub = memory_scrub;
hdev->pldm = 0;
set_driver_behavior_per_device(hdev);