On Tue, Aug 27, 2013 at 02:01:01PM +0100, Mark Salter wrote: > On Tue, 2013-08-27 at 11:49 +0100, Catalin Marinas wrote: > > On Fri, Aug 23, 2013 at 04:16:42PM +0100, Mark Salter wrote: > > > The current vmlinux.lds.S places the notes sections between the > > > end of rw data and start of bss. This means that _edata doesn't > > > really point to the end of data. Since notes are read-only, this > > > patch moves them to the read-only segment so that _edata does > > > point to the end of initialized rw data. > > > > > > Signed-off-by: Mark Salter <[email protected]> > > > --- > > > arch/arm64/kernel/vmlinux.lds.S | 3 +-- > > > 1 file changed, 1 insertion(+), 2 deletions(-) > > > > > > diff --git a/arch/arm64/kernel/vmlinux.lds.S > > > b/arch/arm64/kernel/vmlinux.lds.S > > > index f5e5574..f8ab9d8 100644 > > > --- a/arch/arm64/kernel/vmlinux.lds.S > > > +++ b/arch/arm64/kernel/vmlinux.lds.S > > > @@ -71,6 +71,7 @@ SECTIONS > > > > > > RO_DATA(PAGE_SIZE) > > > EXCEPTION_TABLE(8) > > > + NOTES > > > _etext = .; /* End of text and rodata section */ > > > > > > . = ALIGN(PAGE_SIZE); > > > @@ -122,8 +123,6 @@ SECTIONS > > > } > > > _edata_loc = __data_loc + SIZEOF(.data); > > > > > > - NOTES > > > - > > > BSS_SECTION(0, 0, 0) > > > _end = .; > > > > The _edata is set before NOTES, so I don't fully understand where the > > problem is. > > > The problem *is* _edata before the NOTES. We need a symbol to mark the > end of initialized data. This should be _edata but _edata doesn't > currently account for NOTES. In the EFI stub I'm working on, the PE/COFF > header needs to know the end of the image. If we use _edata, we wouldn't > include NOTES, so we're left with __bss_start. But _bss_start may not be > exactly right because of alignment rounding and it is ugly to use for > that purpose. So we either need a new symbol following NOTES, or move > _edata past NOTES, or move NOTES. I chose the latter because NOTES are > readonly and don't really need to be part of the RW segment.
OK, I got it now. I'll queue the patch for 3.12. Thanks. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
