Subject: Re: mainline build failure due to 281d0c962752 ("fortify: Add Clang support")

From: Sudip Mukherjee <[email-masked]>
Date: Wed, 22 Jun 2022 18:26:04 +0100

On Wed, Jun 22, 2022 at 11:21:09AM -0500, Linus Torvalds wrote:
> On Wed, Jun 22, 2022 at 10:02 AM Nathan Chancellor <[email-masked]> wrote:
> >
> > Right, we are working on a statically linked and optimized build of LLVM
> > that people can use similar to the GCC builds provided on kernel.org,
> > which should make the compile time problem not as bad as well as making
> > it easier for developers to get access to a recent version of clang with
> > all the fixes and improvements that we have made in upstream LLVM.
> 
> So I'm on the road, and will try to see how well I can do that
> allmodconfig build on my poor laptop and see what else goes wrong for
> now.

Tried it after applying your patch. There was no build failure, but some warnings:

fs/reiserfs/reiserfs.o: warning: objtool: leaf_copy_items_entirely+0x7fd: stack state mismatch: cfa1=4+240 cfa2=4+232
arch/x86/kvm/kvm.o: warning: objtool: emulator_cmpxchg_emulated+0x705: call to __ubsan_handle_load_invalid_value() with UACCESS enabled
arch/x86/kvm/kvm.o: warning: objtool: paging64_update_accessed_dirty_bits+0x39e: call to __ubsan_handle_load_invalid_value() with UACCESS enabled
arch/x86/kvm/kvm.o: warning: objtool: paging32_update_accessed_dirty_bits+0x390: call to __ubsan_handle_load_invalid_value() with UACCESS enabled
arch/x86/kvm/kvm.o: warning: objtool: ept_update_accessed_dirty_bits+0x43f: call to __ubsan_handle_load_invalid_value() with UACCESS enabled
drivers/video/fbdev/smscufx.o: warning: objtool: ufx_ops_write() falls through to next function ufx_ops_setcolreg()
drivers/video/fbdev/udlfb.o: warning: objtool: dlfb_ops_write() falls through to next function dlfb_ops_setcolreg()
drivers/soc/qcom/qcom_rpmh.o: warning: objtool: rpmh_rsc_write_ctrl_data() falls through to next function trace_raw_output_rpmh_tx_done()
drivers/scsi/mpi3mr/mpi3mr.o: warning: objtool: mpi3mr_op_request_post() falls through to next function mpi3mr_check_rh_fault_ioc()
drivers/gpu/drm/radeon/radeon.o: warning: objtool: sumo_dpm_set_power_state() falls through to next function sumo_dpm_post_set_power_state()
drivers/net/ethernet/wiznet/w5100.o: warning: objtool: w5100_tx_skb() falls through to next function w5100_get_drvinfo()
drivers/net/ethernet/wiznet/w5100.o: warning: objtool: w5100_rx_skb() falls through to next function w5100_mmio_probe()
vmlinux.o: warning: objtool: __startup_64() falls through to next function startup_64_setup_env()
vmlinux.o: warning: objtool: sync_regs+0x24: call to memcpy() leaves .noinstr.text section
vmlinux.o: warning: objtool: vc_switch_off_ist+0xbe: call to memcpy() leaves .noinstr.text section
vmlinux.o: warning: objtool: fixup_bad_iret+0x36: call to memset() leaves .noinstr.text section
vmlinux.o: warning: objtool: __sev_get_ghcb+0xa0: call to memcpy() leaves .noinstr.text section
vmlinux.o: warning: objtool: __sev_put_ghcb+0x35: call to memcpy() leaves .noinstr.text section

The build took 16 minutes 6 seconds on the build machines in my office (Codethink).

--
Regards
Sudip