Hi Magnus, xen/common/kexec.c references _text, which is not provided by PowerPC''s linker script. Given that you do arithmetic with _end, can you explain why you''re not using _start, which is a standard symbol provided by the default linker script? Outside of Linux, kexec is the only code referencing _text. -- Hollis Blanchard IBM Linux Technology Center _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Wed, 2007-01-03 at 15:07 -0600, Hollis Blanchard wrote:> Given that you do arithmetic with _end, can you explain why you''re not > using _start, which is a standard symbol provided by the default linker > script?My mistake; _start of course isn''t a linker script symbol at all, but rather the entry point code. -- Hollis Blanchard IBM Linux Technology Center _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On 3/1/07 9:22 pm, "Hollis Blanchard" <hollisb@us.ibm.com> wrote:> On Wed, 2007-01-03 at 15:07 -0600, Hollis Blanchard wrote: >> Given that you do arithmetic with _end, can you explain why you''re not >> using _start, which is a standard symbol provided by the default linker >> script? > > My mistake; _start of course isn''t a linker script symbol at all, but > rather the entry point code.There is an unnecessary disagreement among architectures over what symbols should be used to mark section and image boundaries. We could reasonably agree on at least _start/_end and _stext/_etext I think. This would allow functions like is_kernel_text() to become generic, and make it obvious which labels kexec should be using. -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Wed, 2007-01-03 at 21:32 +0000, Keir Fraser wrote:> On 3/1/07 9:22 pm, "Hollis Blanchard" <hollisb@us.ibm.com> wrote: > > > On Wed, 2007-01-03 at 15:07 -0600, Hollis Blanchard wrote: > >> Given that you do arithmetic with _end, can you explain why you''re not > >> using _start, which is a standard symbol provided by the default linker > >> script? > > > > My mistake; _start of course isn''t a linker script symbol at all, but > > rather the entry point code. > > There is an unnecessary disagreement among architectures over what symbols > should be used to mark section and image boundaries. We could reasonably > agree on at least _start/_end and _stext/_etext I think. This would allow > functions like is_kernel_text() to become generic, and make it obvious which > labels kexec should be using.Sounds great to me. PowerPC already arranges for _start to be at the very beginning of .text, which is at the beginning of the first PT_LOAD segment... so the end result is that the address of _start is the same as our link address. We also provide _etext, and _end, but not _stext (currently). -- Hollis Blanchard IBM Linux Technology Center _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On 1/4/07, Keir Fraser <Keir.Fraser@cl.cam.ac.uk> wrote:> There is an unnecessary disagreement among architectures over what symbols > should be used to mark section and image boundaries. We could reasonably > agree on at least _start/_end and _stext/_etext I think. This would allow > functions like is_kernel_text() to become generic, and make it obvious which > labels kexec should be using.I was about to suggest to move the prototypes to a generic header file while at it, but it seems like that someone already done that... Thanks! / magnus _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel