From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Arend van Spriel" Subject: Re: access efi variables Date: Sat, 14 Sep 2013 19:01:19 +0200 Message-ID: <5234965F.3050404@broadcom.com> References: <52333139.6020203@broadcom.com> <5233939B.3020401@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5233939B.3020401-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "H. Peter Anvin" Cc: Matt Fleming , linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-efi@vger.kernel.org On 09/14/13 00:37, H. Peter Anvin wrote: > On 09/13/2013 08:37 AM, Arend van Spriel wrote: >> I need to obtain a uefi variable so I went looking at the API in >> include/linux/efi.h. I found the following definition: >> >> But according to the specs the variable I need to obtain is 2k bytes. >> Should I expect trouble :-p >> > > efivarfs doesn't have those limitations. Thanks, Peter Looking into efivarfs it seems to use the functions that I looked at in efi.h so I guess I am misinterpreting the 1024 bytes limitation in the comment (either that or you are mistaken ;-) ). I need to access the variable from within a device driver so using efivarfs does not feel like the way to go here. Regards, Arend From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932308Ab3INRBb (ORCPT ); Sat, 14 Sep 2013 13:01:31 -0400 Received: from mms3.broadcom.com ([216.31.210.19]:1661 "EHLO mms3.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932262Ab3INRBa (ORCPT ); Sat, 14 Sep 2013 13:01:30 -0400 X-Server-Uuid: B86B6450-0931-4310-942E-F00ED04CA7AF Message-ID: <5234965F.3050404@broadcom.com> Date: Sat, 14 Sep 2013 19:01:19 +0200 From: "Arend van Spriel" User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.9.2.24) Gecko/20111103 Lightning/1.0b2 Thunderbird/3.1.16 MIME-Version: 1.0 To: "H. Peter Anvin" cc: "Matt Fleming" , linux-efi@vger.kernel.org, "linux-kernel@vger.kernel.org" Subject: Re: access efi variables References: <52333139.6020203@broadcom.com> <5233939B.3020401@zytor.com> In-Reply-To: <5233939B.3020401@zytor.com> X-WSS-ID: 7E2A4C602L884776363-01-01 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/14/13 00:37, H. Peter Anvin wrote: > On 09/13/2013 08:37 AM, Arend van Spriel wrote: >> I need to obtain a uefi variable so I went looking at the API in >> include/linux/efi.h. I found the following definition: >> >> But according to the specs the variable I need to obtain is 2k bytes. >> Should I expect trouble :-p >> > > efivarfs doesn't have those limitations. Thanks, Peter Looking into efivarfs it seems to use the functions that I looked at in efi.h so I guess I am misinterpreting the 1024 bytes limitation in the comment (either that or you are mistaken ;-) ). I need to access the variable from within a device driver so using efivarfs does not feel like the way to go here. Regards, Arend