Re: [PATCH v11 05/10] test_firmware: add support for firmware_request_platform

Luis Chamberlain
2020-01-13T14:53:33Z

On Sat, Jan 11, 2020 at 03:56:58PM +0100, Hans de Goede wrote:
> Add support for testing firmware_request_platform through a new
> trigger_request_platform trigger.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> Changes in v11:
> - Drop a few empty lines which were accidentally introduced

But you didn't address my other feedback.

> --- a/lib/test_firmware.c
> +++ b/lib/test_firmware.c
> @@ -507,6 +508,61 @@ static ssize_t trigger_request_store(struct device *dev,
> }
> static DEVICE_ATTR_WO(trigger_request);
>
> +#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE
> +static ssize_t trigger_request_platform_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + static const u8 test_data[] = {
> + 0x55, 0xaa, 0x55, 0xaa, 0x01, 0x02, 0x03, 0x04,
> + 0x55, 0xaa, 0x55, 0xaa, 0x05, 0x06, 0x07, 0x08,
> + 0x55, 0xaa, 0x55, 0xaa, 0x10, 0x20, 0x30, 0x40,
> + 0x55, 0xaa, 0x55, 0xaa, 0x50, 0x60, 0x70, 0x80
> + };
> + struct efi_embedded_fw fw;
> + int rc;
> + char *name;
> +
> + name = kstrndup(buf, count, GFP_KERNEL);
> + if (!name)
> + return -ENOSPC;
> +
> + pr_info("inserting test platform fw '%s'\n", name);
> + fw.name = name;
> + fw.data = (void *)test_data;
> + fw.length = sizeof(test_data);
> + list_add(&fw.list, &efi_embedded_fw_list);
> +
> + pr_info("loading '%s'\n", name);
> +

I mentioned this in my last review, and it seems you forgot to address
this. But now some more feedback:

These two:

> + mutex_lock(&test_fw_mutex);
> + release_firmware(test_firmware);

You are doing this because this is a test, but a typical driver will
do this after, and we don't loose anything in doing this after. Can you
move the mutex lock and assign the pointer to a temporary used pointer
for the call, *after* your call.

But since your test is not using any interfaces to query information
about the firmware, and you are just doing the test in C code right
away, instead of say, using a trigger for later use in userspace,
you can just do away with the mutex lock and make the call use its
own pointer:

rc = firmware_request_platform(&tmp_test_firmware, name, dev);
if (rc) {
...
}
/* Your test branch code goes here */

I see no reason why you use the test_firmware pointer.

> + test_firmware = NULL;
> + rc = firmware_request_platform(&test_firmware, name, dev);
> + if (rc) {
> + pr_info("load of '%s' failed: %d\n", name, rc);
> + goto out;
> + }
> + if (test_firmware->size != sizeof(test_data) ||
> + memcmp(test_firmware->data, test_data, sizeof(test_data)) != 0) {
> + pr_info("firmware contents mismatch for '%s'\n", name);
> + rc = -EINVAL;
> + goto out;
> + }
> + pr_info("loaded: %zu\n", test_firmware->size);
> + rc = count;
> +
> +out:
> + mutex_unlock(&test_fw_mutex);
> +
> + list_del(&fw.list);
> + kfree(name);
> +
> + return rc;
> +}