Re: linux-next: Tree for Apr 16 (objtool: warnings)
From: Randy Dunlap <hidden>
Date: 2021-06-21 23:30:13
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On 6/21/21 7:23 AM, Peter Zijlstra wrote:
On Mon, Jun 21, 2021 at 03:34:32PM +0200, Peter Zijlstra wrote:quoted
On Fri, Apr 16, 2021 at 10:50:49AM -0700, Randy Dunlap wrote:quoted
On 4/16/21 4:36 AM, Stephen Rothwell wrote:quoted
Hi all, Changes since 20210415:on x86_64, objtool is not liking retpoline.o: $ gcc --version gcc (SUSE Linux) 7.5.0 Is there already a patch for these? ===== build-r8840.out ===== arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_rax()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_rbx()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_rcx()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_rdx()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_rsi()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_rdi()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_rbp()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r8()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r9()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r10()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r11()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r12()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r13()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r14()+0x0: call without frame pointer save/setup arch/x86/lib/retpoline.o: warning: objtool: __x86_indirect_alt_call_r15()+0x0: call without frame pointer save/setupDamn, sorry I missed this. I know what the problem is, but I've yet to find a solution that's not terrible... hold on.--- Subject: objtool/x86: Ignore __x86_indirect_alt_* symbols From: Peter Zijlstra <peterz@infradead.org> Date: Mon Jun 21 16:13:55 CEST 2021 Because the __x86_indirect_alt* symbols are just that, objtool will try and validate them as regular symbols, instead of the alternative replacements that they are. This goes sideways for FRAME_POINTER=y builds; which generate a fair amount of warnings. Fixes: 9bc0bb50727c ("objtool/x86: Rewrite retpoline thunk calls") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Looks good in my testing. Thanks. Acked-by: Randy Dunlap <redacted> # build-tested
quoted hunk ↗ jump to hunk
--- arch/x86/lib/retpoline.S | 4 ++++ 1 file changed, 4 insertions(+)--- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S@@ -58,12 +58,16 @@ SYM_FUNC_START_NOALIGN(__x86_indirect_al 2: .skip 5-(2b-1b), 0x90 SYM_FUNC_END(__x86_indirect_alt_call_\reg) +STACK_FRAME_NON_STANDARD(__x86_indirect_alt_call_\reg) + SYM_FUNC_START_NOALIGN(__x86_indirect_alt_jmp_\reg) ANNOTATE_RETPOLINE_SAFE 1: jmp *%\reg 2: .skip 5-(2b-1b), 0x90 SYM_FUNC_END(__x86_indirect_alt_jmp_\reg) +STACK_FRAME_NON_STANDARD(__x86_indirect_alt_jmp_\reg) + .endm /*
-- ~Randy