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 MyBi/ry/ mOyhHO8k5sdrda7V+jKAufMl/HkRSloUX4puaCuuPeNCjIEFuJvXHDgRmGF/ewZwPNIWHJSsHY5HetuXBXak3TUHgPXzLvqCniJ7PDbRWPVrc1kc9XYCA+Q3tCLmS4BEb6C834NKyIHIoKNTW3TWgAvmJmg8gFY8uEQ4lutBJvFgs8U/dXcTZlwkkNQHYh0FYOsS6psghiaeLysa/cJ7u7CXWtpZerJHujPq2qoNkUQcNIUYJn0xrp+jWQ5+l5AvoO8oQdGMICxvSRMiSLWp8eN32N0X53/VmOXrrzJIKvksoMsirIfBP5/ibxg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Brendan, > .:: Minor issues > > - fill_return_buffer() causes an “unreachable instruction” objtool > warning. I haven’t investigated this. > + > +.pushsection .noinstr.text, "ax" > +SYM_CODE_START(fill_return_buffer) > + __FILL_RETURN_BUFFER(%_ASM_AX,RSB_CLEAR_LOOPS) > + RET > +SYM_CODE_END(fill_return_buffer) > +.popsection > I'm getting this error when buiding the ASI patchset: OBJCOPY modules.builtin.modinfo GEN modules.builtin GEN .vmlinux.objs MODPOST Module.symvers ERROR: modpost: "fill_return_buffer" [arch/x86/kvm/kvm.ko] undefined! make[2]: *** [scripts/Makefile.modpost:145: Module.symvers] Error 1 make[1]: *** [/home/shivank/linux/Makefile:1871: modpost] Error 2 make: *** [Makefile:240: __sub-make] Error 2 I'm wondering if we need to annotate the asm code with UNWIND_HINT_FUNC and EXPORT the fill_return_buffer and to avoid this? --- diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S index db5b8ee01efe..4084ab49e2a7 100644 --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -399,7 +399,9 @@ EXPORT_SYMBOL(__x86_return_thunk) .pushsection .noinstr.text, "ax" SYM_CODE_START(fill_return_buffer) + UNWIND_HINT_FUNC __FILL_RETURN_BUFFER(%_ASM_AX,RSB_CLEAR_LOOPS) RET SYM_CODE_END(fill_return_buffer) +__EXPORT_THUNK(fill_return_buffer) .popsection --- This solved the issue for me. Thanks, Shivank