Revert "objtool: Support addition to set CFA base"

[ Upstream commit e18398e80c73e3cc7d9c3d2e0bc06a4af8f4f1cb ]

Commit 468af56a7bba ("objtool: Support addition to set CFA base") was
added as a preparatory patch for arm64 support, but that support never
came.  It triggers a false positive warning on x86, so just revert it
for now.

Fixes the following warning:

  vmlinux.o: warning: objtool: cdce925_regmap_i2c_write+0xdb: stack state mismatch: cfa1=4+120 cfa2=5+40

Fixes: 468af56a7bba ("objtool: Support addition to set CFA base")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/oe-kbuild-all/202304080538.j5G6h1AB-lkp@intel.com/
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 730b49e..c2c3509 100644 (file)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2757,17 +2757,6 @@ static int update_cfi_state(struct instruction *insn,
                                break;
                        }
 
-                       if (!cfi->drap && op->src.reg == CFI_SP &&
-                           op->dest.reg == CFI_BP && cfa->base == CFI_SP &&
-                           check_reg_frame_pos(&regs[CFI_BP], -cfa->offset + op->src.offset)) {
-
-                               /* lea disp(%rsp), %rbp */
-                               cfa->base = CFI_BP;
-                               cfa->offset -= op->src.offset;
-                               cfi->bp_scratch = false;
-                               break;
-                       }
-
                        if (op->src.reg == CFI_SP && cfa->base == CFI_SP) {
 
                                /* drap: lea disp(%rsp), %drap */