objtool errors and warnings with gcc-16.1.0, linux-next-20260518

[Arnd Bergmann]

I got two new build failures on x86 randconfig builds, plus a few
warnings on linux-next. All of these are with the fresh gcc-16.1
binaries I published on kernel.org.

I have not tried to analyze any of these.

Attached .config and object files.

    Arnd

==> build/x86/0xA3E4F788_defconfig/log <==
lib/alloc_tag.o: error: objtool: pgalloc_tag_swap+0x70f: stack state mismatch: reg1[13]=-1+0 reg2[13]=-2-32

==> build/x86/0xCB605A07_defconfig/log <==
lib/xarray.o: error: objtool: xa_get_mark+0x204: return with modified stack frame

==> build/x86/0xA1816CA7_defconfig/log <==
drivers/media/cec/core/cec-adap.o: warning: objtool: cec_receive_notify.isra.0+0x5b5: ignoring unreachables due to jump table quirk

==> build/x86/0x7EB45B1E_defconfig/log <==
vmlinux.o: warning: objtool: ncsi_process_next_channel+0x1f2: stack state mismatch: reg1[15]=-1+0 reg2[15]=-2-16

==> build/x86/0xF2C7EA44_defconfig/log <==
drivers/video/fbdev/core/cfbcopyarea.o: warning: objtool: cfb_copyarea+0x1bdc: stack state mismatch: reg1[13]=-1+0 reg2[13]=-2-32
drivers/video/fbdev/core/syscopyarea.o: warning: objtool: sys_copyarea+0x1b3c: stack state mismatch: reg1[15]=-1+0 reg2[15]=-2-16

==> build/x86/0xAF34B57E_defconfig/log <==
vmlinux.o: warning: objtool: hdmi_power_on_full.isra.0+0x192: hdmi_pll_compute() missing __noreturn in .c/.h or NORETURN() in noreturns.h
vmlinux.o: warning: objtool: hdmi_power_on_full.isra.0+0x170: hdmi_pll_compute() missing __noreturn in .c/.h or NORETURN() in noreturns.h
vmlinux.o: warning: objtool: hdmi_power_on_full.isra.0.cold+0x0: unreachable instruction
vmlinux.o: warning: objtool: hdmi_power_on_full.isra.0.cold+0xa: unreachable instruction

Attachment: objtool-20260519.tar.gz
Description: application/gzip