Re: clang/objtool failures on linux-next

[Josh Poimboeuf]

On Fri, Mar 06, 2026 at 10:02:54PM +0100, Arnd Bergmann wrote:
> On Fri, Mar 6, 2026, at 19:29, Josh Poimboeuf wrote:
> > On Fri, Mar 06, 2026 at 09:31:02AM -0800, Josh Poimboeuf wrote:
> >> On Fri, Mar 06, 2026 at 01:41:59PM +0100, Arnd Bergmann wrote:
> >> 
> >> Thanks, I'll post a fix for the 1st one right now (haven't looked at the
> >> stack overflow yet).
> >
> > Both fixes posted now:
> >
> > https://lore.kernel.org/240e6a172cc73292499334a3724d02ccb3247fc7.1772818491.git.jpoimboe@xxxxxxxxxx
> > https://lore.kernel.org/8b97f62d083457f3b0a29a424275f7957dd3372f.1772821683.git.jpoimboe@xxxxxxxxxx
> 
> Thanks a lot, that was quick!
> 
> I've applied both to my randconfig tree now and verified that
> both issues are addressed in the full build. There is still
> the question of the 0xAE77DEF6_defconfig causing an incredibly
> long compile time (minutes!) for the one file when using clang.
> 
> I've added Nathan to Cc in case he is motivated to try to
> reproduce this.
> 
> FWIW, this is the current set of objtool warnings that I get that
> don't cause the build to fail:
> 
> drivers/gpu/drm/amd/amdgpu/amdgpu_cs.o: warning: objtool: amdgpu_cs_parser_bos+0x723: unreachable instruction
> drivers/gpu/drm/msm/msm.o: warning: objtool: msm_gem_vm_close+0x1cf: unreachable instruction
> drivers/gpu/drm/panthor/panthor.o: warning: objtool: panthor_ioctl_vm_bind+0x32b: __stack_chk_fail() missing __noreturn in .c/.h or NORETURN() in noreturns.h
> drivers/gpu/drm/panthor/panthor.o: warning: objtool: panthor_ioctl_vm_bind_async+0x285: unreachable instruction
> drivers/gpu/drm/panthor/panthor_drv.o: warning: objtool: panthor_ioctl_vm_bind+0x2df: unreachable instruction
> drivers/gpu/drm/xe/xe_bo.o: warning: objtool: xe_bo_create_pin_map_at_novm+0x11d: unreachable instruction
> drivers/iio/imu/bmi160/bmi160_core.o: warning: objtool: bmi160_setup_irq() falls through to next function __cfi_bmi160_core_runtime_resume()
> kernel/bpf/core.o: warning: objtool: ___bpf_prog_run+0x217: sibling call from callable instruction with modified stack frame
> sound/soc/codecs/wcd9335.o: warning: objtool: wcd9335_slimbus_irq() falls through to next function __cfi_wcd9335_set_channel_map()
> vmlinux.o: warning: objtool: ___bpf_prog_run+0x1d4: sibling call from callable instruction with modified stack frame
> vmlinux.o: warning: objtool: hdmi_power_on_full.isra.0+0xd6: hdmi_pll_compute() missing __noreturn in .c/.h or NORETURN() in noreturns.h
> 
> If you want to investigate those, I can send you the configs and/or
> object files for these as well.

Yes, please send those and I'll take a look.  Thanks!

-- 
Josh