Le 24/02/2011 13:58, Po-Yu Chuang a écrit : > Hi Albert, > > On Thu, Feb 24, 2011 at 7:58 PM, Albert ARIBAUD<albert.arib...@free.fr> > wrote: >> Le 24/02/2011 10:39, Wolfgang Denk a écrit : >>> >>> Dear Albert ARIBAUD, >>> >>> In message<4d6611a7.5050...@free.fr> you wrote: >>>> >>>>>>> In the U-Boot image itself, knowing the image size could be achieved >>>>>>> in >>>>>>> ARM by using a general _end symbol that would be set after the last >>>>>>> image output section, so _end-_start would equal the image size. >>>>>> >>>>>> we have such a "_end" in u-boot.lds files. >>>> >>>> I *knew* this name did not pop up in my mind without a reason. :) >>>> >>>> Apologies for not having checked. >>>> >>>>> I guess we need a __dynsym_end in all u-boot.lds files. >>>> >>>> I'd rather go for "_end", which does not tie the solution to dynsym >>>> being the last section in the image -- imagine for some reason we move >>>> dynsym inside the image rather than at the end, end the image size will >>>> be wrong again. With _end, and a suitable comment in the LD file... this >>>> will be averted where-ever dynsym ends up. >>>> >>>> After all, the bug you uncovered was due to using the wrong symbol, a >>>> BSS related one rather than an image-related one, in the first place; so >>>> let's try and learn from past mistakes. >>> >>> I think the location of _end in the linker scripts needs to be changed >>> - so far it covers the maximum of dynsym and bss, but it should refer >>> to the end of dynsym only. >> >> Po-Yu Chuang, can you verify Wolfgang's suggestion (and make sure no other >> place depends on _end) and submit a patch? As this is a fix, a quick patch >> could still be pulled in for the upcoming release. > > I think there is a problem in Wolfgang's suggestion. > > Those start.S files assume that BSS section is from __bss_start to _end. > If we change _end to the end of .dynsym, then we will not clear BSS correctly. > > I agree with your comment about _end is a better choice than __dynsym_end, > but if we changed _end, maybe we need __bss_end? Either way, we need to > modify all the u-boot.lds and/or start.S. > > I still don't know what is the best solution.
Thanks for pointing this out: indeed, _end is actually used as BSS's end, not as the image's end -- I did not find any other use of it. However, not only ARM uses _end: how do we want to handle the change overall? > best regards, > Po-Yu Chuang Amicalement, -- Albert. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
