Re: [PATCH v2] selftests/efivarfs: skip write tests if efivarfs is mounted read-only

["Ard Biesheuvel" <ardb@kernel.org>]

On Fri, 4 Sep 2026, at 04:06, Hui Wang wrote:
> The previous mail was rejected by linux-kselftest maillist because the 
> html part is detected. Fixing it and re-sending the mail.
>
> On 9/3/26 17:34, Ard Biesheuvel wrote:
>>>   run_test()
>>> @@ -74,7 +82,7 @@ test_create_empty()
>>>   {
>>>   	local file=$efivarfs_mount/$FUNCNAME-$test_guid
>>>
>>> -	: > $file
>>> +	: 2>/dev/null > $file
>>>
>> Why is this needed?
> The test_create_empty() will be run on read-only efivarfs, and it will 
> print [PASS], but it will also print some noise message with read-only 
> filesystem like:
>
> --------------------
> running test_create_empty
> --------------------
> $(TESTCASE_PATH)/efivarfs.sh: line 85: 
> /sys/firmware/efi/efivars/test_create_empty-210be57c-9849-4fc7-a635-e6382d1aec27: 
> Read-only file system
>    [PASS]
>
> This change is for suppressing the noise message and make the output 
> clean like below:
>
> --------------------
> running test_create_empty
> --------------------
>    [PASS]
>

That does not make sense.

If the file does not exist after attempting to create it, the test has failed.
But I suspect that this fails even on a read-write efivarfs, given that EFI
does not support zero-length variables.

Please fix this in a separate patch, or leave it alone. Don't paper over it
like this.