x86, relocs: Add jiffies and jiffies_64 to the relative whitelist commit ea17e7414bc62e8d3bde8d08e3df1d921c518c17 upstream. The symbol jiffies is created in the linker script as an alias to jiffies_64. Unfortunately this is done outside any section, and apparently GNU ld 2.21 doesn't carry the section with it, so we end up with an absolute symbol and therefore a broken kernel. Add jiffies and jiffies_64 to the whitelist. The most disturbing bit with this discovery is that it shows that we have had multiple linker bugs in this area crossing multiple generations, and have been silently building bad kernels for some time. Link: http://lkml.kernel.org/r/20120524171604.0d98284f3affc643e9714470@canb.auug.org.au Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
x86-32, relocs: Whitelist more symbols for ld bug workaround commit fd952815307f0f272bf49fd364a7fd2f9992bc42 upstream. As noted in checkin: a3e854d95 x86, relocs: Workaround for binutils 2.22.52.0.1 section bug ld version 2.22.52.0.[12] can incorrectly promote relative symbols to absolute, if the output section they appear in is otherwise empty. Since checkin: 6520fe55 x86, realmode: 16-bit real-mode code support for relocs tool we actually check for this and error out rather than silently creating a kernel which will malfunction if relocated. Ingo found a configuration in which __start_builtin_fw triggered the warning. Go through the linker script sources and look for more symbols that could plausibly get bogusly promoted to absolute, and add them to the whitelist. In general, if the following error triggers: Invalid absolute R_386_32 relocation: <symbol> ... then we should verify that <symbol> is really meant to be relocated, and add it and any related symbols manually to the S_REL regexp. Please note that 6520fe55 does not introduce the error, only the check for the error -- without 6520fe55 this version of ld will simply produce a corrupt kernel if CONFIG_RELOCATABLE is set on x86-32. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
x86, relocs: When printing an error, say relative or absolute commit 24ab82bd9bf18f3efc69a131d73577940941e1b7 upstream. When the relocs tool throws an error, let the error message say if it is an absolute or relative symbol. This should make it a lot more clear what action the programmer needs to take and should help us find the reason if additional symbol bugs show up. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
x86, relocs: Workaround for binutils 2.22.52.0.1 section bug commit a3e854d95a76862cd37937e0b0438f540536771a upstream. GNU ld 2.22.52.0.1 has a bug that it blindly changes symbols from section-relative to absolute if they are in a section of zero length. This turns the symbols __init_begin and __init_end into absolute symbols. Let the relocs program know that those should be treated as relative symbols. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: H.J. Lu <hjl.tools@gmail.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
x86, realmode: 16-bit real-mode code support for relocs tool commit 6520fe5564acf07ade7b18a1272db1184835c487 upstream. A new option is added to the relocs tool called '--realmode'. This option causes the generation of 16-bit segment relocations and 32-bit linear relocations for the real-mode code. When the real-mode code is moved to the low-memory during kernel initialization, these relocation entries can be used to relocate the code properly. In the assembly code 16-bit segment relocations must be relative to the 'real_mode_seg' absolute symbol. Linear relocations must be relative to a symbol prefixed with 'pa_'. 16-bit segment relocation is used to load cs:ip in 16-bit code. Linear relocations are used in the 32-bit code for relocatable data references. They are declared in the linker script of the real-mode code. The relocs tool is moved to arch/x86/tools/relocs.c, and added new target archscripts that can be used to build scripts needed building an architecture. be compiled before building the arch/x86 tree. [ hpa: accelerating this because it detects invalid absolute relocations, a serious bug in binutils 2.22.52.0.x which currently produces bad kernels. ] Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1336501366-28617-2-git-send-email-jarkko.sakkinen@intel.com Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> [bwh: Backported to 3.2: - Adjust context (no archheaders; no insn_sanity) - Expand put_unaligned_le32()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>