On Wed, 2008-07-02 at 02:00 +0200, Denys Vlasenko wrote: > On Wednesday 02 July 2008 01:41, James Bottomley wrote: > > On Wed, 2008-07-02 at 02:39 +0200, Denys Vlasenko wrote: > > > The purpose of this patch is to make kernel buildable > > > with "gcc -ffunction-sections -fdata-sections". > > > This patch fixes parisc architecture. > > > > > > Signed-off-by: Denys Vlasenko <vda.linux@xxxxxxxxxxxxxx> > > > > Um ... if you look at the Makefile you'll see we already build parisc > > with -ffunction-sections; we have to: our relative jumps are too small > > to guarantee finding the stubs in large files. > > > > Since our text is -ffunction-sections compatible already, I question the > > need for transformations like this: > > > > > - *(.text.do_softirq) > > > - *(.text.sys_exit) > > > - *(.text.do_sigaltstack) > > > - *(.text.do_fork) > > > + *(.do_softirq.text) > > > + *(.sys_exit.text) > > > + *(.do_sigaltstack.text) > > > + *(.do_fork.text) > > arch/parisc/kernel/vmlinux.lds.S contains these lines: > > TEXT_TEXT > SCHED_TEXT > LOCK_TEXT > *(.text.do_softirq) > *(.text.sys_exit) > *(.text.do_sigaltstack) > *(.text.do_fork) > > which suggested to me that for parisc it is important to have > these sections in that place (after LOCK_TEXT) and order. Yes ... moderately. > If you use -ffunction-sections, any function with the name > do_fork (say, a static function somewhere) will end up in > .text.do_fork function, and will be "mixed up" with > global do_fork(). For parisc it is maybe not a problem > (I am not an expert) but in other places/arches people > clearly would not want this kind of things to happen. Erm, but we're trying to name text sections of the -ffunction-sections. We're doing this because we are trying to do a semblance of a reasonable arrangement for the relative jumps (and avoid stubs). Your patch is explicitly breaking all of this. > In order to handle these situations uniformly, in these patches > I decided to _never_ use .text.XXXX names for sections, > effectively leaving them "reserved for gcc's use". We need to use the names gcc outputs, not some random name. > Did I understand you right that in this chunk I need to > leave .text.FUNC_NAME as it was before? Yes. > > And thus by the same token the data transformations. > > It would be easiest for me if you will reply to the parisc patch > and indicate all parts where I should NOT do name change. That would be the piece above. James -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
