From mboxrd@z Thu Jan 1 00:00:00 1970 From: shc_work@mail.ru (=?UTF-8?B?QWxleGFuZGVyIFNoaXlhbg==?=) Date: Sat, 17 Aug 2013 18:12:04 +0400 Subject: =?UTF-8?B?UmU6IFN0YXJ0IHN5bWJvbCBmb3IgYW4gY29tcHJlc3NlZCBrZXJuZWw=?= References: <20130817135751.GL23006@n2100.arm.linux.org.uk> Message-ID: <1376748724.761782391@f272.i.mail.ru> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org > 2013/8/17 Russell King - ARM Linux : > > On Sat, Aug 17, 2013 at 09:56:14PM +0800, zhaobin xv wrote: > >> 2013/8/17 Russell King - ARM Linux : > >> > On Sat, Aug 17, 2013 at 07:39:46PM +0800, zhaobin xv wrote: > >> >> how to find Start symbol for an compressed kernel for arm > >> > > >> > The start address of a compressed kernel is the first byte of the image. > >> > > >> > Symbolically, that is 'start', which is a non-global symbol. However, > >> > this symbol is useless since it normally is zero, because the entire > >> > image is relocatable and therefore built for address zero. > >> > > >> > However, it is normal to load the image not at address zero. > >> > >> why do U define ENTRY(_start)? > >> Is _start the Start symbol? > >> how to explain _start > > > > There is no _start symbol in the compressed kernel. > > But there is ENTRY(_start) and _start in > linux-2.6.22.6\arch\arm\boot\compressed/head.S I always thought that the "start" is necessary for the compiler to tell it what is at the beginning of the program. So, on my opinion this is just a way to tell to gcc where we should place initial kernel data. ---