[RFC 23/31] objtool: Handle __pa_symbol() relocations

Josh Poimboeuf
2024-09-03T04:00:41Z

A relocation created by __pa_symbol() has a large addend referring to a
physical address. Convert it to back its virtual form before
calculating the addend.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
tools/objtool/arch/x86/decode.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index afebd67d9b9d..5468fd15f380 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -67,6 +67,17 @@ bool arch_callee_saved_reg(unsigned char reg)
}
}

+/* undo the effects of __pa_symbol() if necessary */
+static unsigned long phys_to_virt(unsigned long pa)
+{
+ s64 va = pa;
+
+ if (va > 0)
+ va &= ~(0x80000000);
+
+ return va;
+}
+
s64 arch_insn_adjusted_addend(struct instruction *insn, struct reloc *reloc)
{
s64 addend = reloc_addend(reloc);
@@ -80,7 +91,7 @@ s64 arch_insn_adjusted_addend(struct instruction *insn, struct reloc *reloc)
break;
}

- return addend;
+ return phys_to_virt(addend);
}

unsigned long arch_jump_destination(struct instruction *insn)
--
2.45.2