drm/amdkfd: clamp queue size to minimum

[ Upstream commit e90711946b53590371ecce32e8fcc381a99d6333 ]

If queue size is less than minimum, clamp it to minimum to prevent
underflow when writing queue mqd.

Signed-off-by: David Yat Sin <David.YatSin@amd.com>
Reviewed-by: Jay Cornwall <jay.cornwall@amd.com>
Reviewed-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index 065d8784145918f450bf42637c9df6569ff50394..33df35cab46791eb14ffa60ec89cf8514addebfa 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -212,6 +212,11 @@ static int set_queue_properties_from_user(struct queue_properties *q_properties,
                return -EINVAL;
        }
 
+       if (args->ring_size < KFD_MIN_QUEUE_RING_SIZE) {
+               args->ring_size = KFD_MIN_QUEUE_RING_SIZE;
+               pr_debug("Size lower. clamped to KFD_MIN_QUEUE_RING_SIZE");
+       }
+
        if (!access_ok((const void __user *) args->read_pointer_address,
                        sizeof(uint32_t))) {
                pr_err("Can't access read pointer\n");
@@ -461,6 +466,11 @@ static int kfd_ioctl_update_queue(struct file *filp, struct kfd_process *p,
                return -EINVAL;
        }
 
+       if (args->ring_size < KFD_MIN_QUEUE_RING_SIZE) {
+               args->ring_size = KFD_MIN_QUEUE_RING_SIZE;
+               pr_debug("Size lower. clamped to KFD_MIN_QUEUE_RING_SIZE");
+       }
+
        properties.queue_address = args->ring_base_address;
        properties.queue_size = args->ring_size;
        properties.queue_percent = args->queue_percentage & 0xFF;

diff --git a/include/uapi/linux/kfd_ioctl.h b/include/uapi/linux/kfd_ioctl.h
index fa9f9846b88e4da137138e43aee854057fae93a7..b0160b09987c1fd188d5b23434eae28178796f9c 100644 (file)
--- a/include/uapi/linux/kfd_ioctl.h
+++ b/include/uapi/linux/kfd_ioctl.h
@@ -62,6 +62,8 @@ struct kfd_ioctl_get_version_args {
 #define KFD_MAX_QUEUE_PERCENTAGE       100
 #define KFD_MAX_QUEUE_PRIORITY         15
 
+#define KFD_MIN_QUEUE_RING_SIZE                1024
+
 struct kfd_ioctl_create_queue_args {
        __u64 ring_base_address;        /* to KFD */
        __u64 write_pointer_address;    /* from KFD */