Re: ACK: [PATCH 1/1] efi/efi_test: read RuntimeServicesSupported

From: Heinrich Schuchardt <xypron.glpk@gmx.de>
To: Ard Biesheuvel <ardb@kernel.org>,
	Colin Ian King <colin.king@canonical.com>
Cc: Ivan Hu <ivan.hu@canonical.com>,
	linux-efi <linux-efi@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	fwts-devel@lists.ubuntu.com
Subject: Re: ACK: [PATCH 1/1] efi/efi_test: read RuntimeServicesSupported
Date: Fri, 27 Nov 2020 20:39:31 +0100	[thread overview]
Message-ID: <fac1a832-b5ce-8eea-d1aa-81a0f429d772@gmx.de> (raw)
In-Reply-To: <CAMj1kXFNtCJEvbhZpO9p96UNGuo-r2dXQPm0TRjmQuF4TLBUcg@mail.gmail.com>

On 11/27/20 8:29 PM, Ard Biesheuvel wrote:
> On Fri, 27 Nov 2020 at 20:28, Colin Ian King <colin.king@canonical.com> wrote:
>>
>> On 27/11/2020 19:20, Heinrich Schuchardt wrote:
>>> Since the UEFI 2.8A specification the UEFI enabled firmware provides a
>>> configuration table EFI_RT_PROPERTIES_TABLE which indicates which runtime
>>> services are enabled. The EFI stub reads this table and saves the value of
>>> the field RuntimeServicesSupported internally.
>>>
>>> The Firmware Test Suite requires the value to determine if UEFI runtime
>>> services are correctly implemented.
>>>
<snip />
>> Looks good to me. Thanks Heinrich.
>>
>> The EFI driver needs to be also updated in the linux kernel - has that
>> fix been submitted or do you require the fwts team to do that?
>>
>
> This /is/ the EFI driver.
>
> I'll take this as an acked-by but I'd like Ivan to chime in as well.
>

Hello Ard, hello Colin,

I have tested the patch with Linux 5.8.9.

Somehow Linux managed to break the kernel for my board between Linux
5.8.9 and 5.8.18. It does not boot form iSCSI with a newer kernel.

You probably want to run a user program against your latest kernel. This
is what I used:

#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>

#define EFI_RUNTIME_GET_SUPPORTED_MASK \
         _IOR('p', 0x0C, unsigned int)

int main()
{
         unsigned int i, flag;
         int fd, ret;
         unsigned int mask;

         fd = open("/dev/efi_test", O_RDWR);
         if (fd == -1) {
                 perror("open");
                 return 1;
         }

         ret = ioctl(fd, EFI_RUNTIME_GET_SUPPORTED_MASK, &mask);
         if (ret == -1) {
                 perror("ioctl");
                 return 1;
         }
         printf("mask 0x%08x\n", mask);

         flag = 1;
         for (i = 0x80000000; i; i >>= 1) {
                 if (i & mask) {
                         printf("%4s 0x%08x\n", flag ? "=" : "|", i);
                         flag = 0;
                 }
         }

         close(fd);

         return 0;
}

Best regards

Heinrich