From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hubert CHAUMETTE Subject: Re: x86_64_defconfig and i386_defconfig: What is the difference? Date: Tue, 09 Sep 2014 17:28:36 +0200 Message-ID: <540F1CA4.9090806@wanadoo.fr> References: <540F094F.3040904@gmail.com> <75730.1410272873@turing-police.cc.vt.edu> <5c5bb43b899f41d0baa2d358168e9b39@DM2PR05MB671.namprd05.prod.outlook.com> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <5c5bb43b899f41d0baa2d358168e9b39@DM2PR05MB671.namprd05.prod.outlook.com> Sender: linux-newbie-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="iso-8859-1" To: Rajat Jain , "Valdis.Kletnieks@vt.edu" , Matthias Brugger Cc: "linux-newbie@vger.kernel.org" , kernelnewbies Le 09/09/2014 17:11, Rajat Jain a =E9crit : > Hi, > > Thank you all for your responses. I got the answer I was looking for: > >> Hello Rajat, >> >> Indeed, the i386 is for 32bits kernels, and x86_64 for 64 bits ones.= If you >> generate the configurations using "make ARCH=3Dx86 defconfig" and "m= ake >> ARCH=3Di386 defconfig", you can easily compare the resulting configu= rations : >> >> .config from i386_defconfig : >> # >> # Automatically generated file; DO NOT EDIT. >> # Linux/i386 3.17.0-rc1 Kernel Configuration # # CONFIG_64BIT is not= set >> CONFIG_X86_32=3Dy CONFIG_X86=3Dy CONFIG_INSTRUCTION_DECODER=3Dy >> CONFIG_OUTPUT_FORMAT=3D"elf32-i386" >> CONFIG_ARCH_DEFCONFIG=3D"arch/x86/configs/i386_defconfig" >> ... >> >> .config from x86_64_defconfig : >> # >> # Automatically generated file; DO NOT EDIT. >> # Linux/x86 3.17.0-rc1 Kernel Configuration # CONFIG_64BIT=3Dy >> CONFIG_X86_64=3Dy CONFIG_X86=3Dy CONFIG_INSTRUCTION_DECODER=3Dy >> CONFIG_OUTPUT_FORMAT=3D"elf64-x86-64" >> CONFIG_ARCH_DEFCONFIG=3D"arch/x86/configs/x86_64_defconfig" >> ... >> >> As you can see, i386 is the 32 bits variant of the x86 architecture.= There are of >> course many more differences between these two configurations. >> >> Regards, >> >> Hubert > Thanks all again, > > Rajat > > >> -----Original Message----- >> From: Valdis.Kletnieks@vt.edu [mailto:Valdis.Kletnieks@vt.edu] >> Sent: Tuesday, September 09, 2014 7:28 AM >> To: Matthias Brugger >> Cc: Rajat Jain; linux-newbie@vger.kernel.org; kernelnewbies >> Subject: Re: x86_64_defconfig and i386_defconfig: What is the differ= ence? >> >> On Tue, 09 Sep 2014 16:06:07 +0200, Matthias Brugger said: >> >>>> Can someone tell me if the i386 one is to be used when we want to >>>> build for a 32bit machine and the x86_64 is to be used for 64 bit = machine? >>> You can build the kernel with any architecture for any architecture= =2E >>> This is called cross-compiling. The homepage [0] should explain you >>> how to do that. >> Right, but you still need to use a .config appropriate for the targe= t machine, >> which is what I think Rajat was asking about. >> >> A defconfig is usually only known verified to boot on a few (possibl= y one) >> examples of that architecture hardware. For embedded ARM, it may be= one >> specific development board or hardware device. For x86, I think the= y try to >> keep it "will probably kind of sort of boot on generic PC hardware w= ith a >> common distro, but anything fancylike a webcam or better graphics th= an "vga >> tty emulation" may not work". >> >> A defconfig is pretty much just a proof of concept starting point fo= r an actual >> working config for a given hardware system. > -- > To unsubscribe from this list: send the line "unsubscribe linux-newbi= e" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.linux-learn.org/faqs Sorry, I mistakenly replied only to the OP. -- To unsubscribe from this list: send the line "unsubscribe linux-newbie"= in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.linux-learn.org/faqs