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 9a444b17530a46a12997a2ac6f9fa5c4db679c16..869c8786df5c941d001533bbaac1995510ceb969 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -190,6 +190,11 @@ 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");
@@ -394,6 +399,11 @@ 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;

diff --git a/include/uapi/linux/kfd_ioctl.h b/include/uapi/linux/kfd_ioctl.h
index 695b606da4b15b58704c68de601cdbc178b5ca2f..94af84e845549edd5f39c6de56c1f50dfda18b4e 100644 (file)
--- a/include/uapi/linux/kfd_ioctl.h
+++ b/include/uapi/linux/kfd_ioctl.h
@@ -47,6 +47,8 @@ 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 */