Subject: Re: linux-next: build warnings after merge of the tip tree

From: Stephen Rothwell <[email-masked]>
Date: Sat, 22 Jan 2022 10:58:06 +1100

Hi all,

On Fri, 17 Dec 2021 14:40:04 +1100 Stephen Rothwell <[email-masked]> wrote:
>
> After merging the tip tree, today's linux-next build (x86_64 allmodconfig)
> produced these warnings:
> 
> lib/strnlen_user.o: warning: objtool: strnlen_user()+0xc9: call to do_strnlen_user() with UACCESS enabled
> lib/strncpy_from_user.o: warning: objtool: strncpy_from_user()+0x129: call to do_strncpy_from_user() with UACCESS enabled
> vmlinux.o: warning: objtool: mce_start()+0x5c: call to __kasan_check_write() leaves .noinstr.text section
> vmlinux.o: warning: objtool: mce_gather_info()+0x5f: call to v8086_mode.constprop.0() leaves .noinstr.text section
> vmlinux.o: warning: objtool: mce_read_aux()+0x8a: call to mca_msr_reg() leaves .noinstr.text section
> vmlinux.o: warning: objtool: do_machine_check()+0x192: call to mce_no_way_out() leaves .noinstr.text section
> vmlinux.o: warning: objtool: mce_severity_amd.constprop.0()+0xca: call to mce_severity_amd_smca() leaves .noinstr.text section
> 
> I am not sure which changes caused the above.

I currently still get the following warnings from an x86_64
allmodconfig build fo Linus' tree:

vmlinux.o: warning: objtool: mce_start()+0x5c: call to __kasan_check_write() leaves .noinstr.text section
vmlinux.o: warning: objtool: mce_gather_info()+0x5f: call to v8086_mode.constprop.0() leaves .noinstr.text section
vmlinux.o: warning: objtool: mce_read_aux()+0x8a: call to mca_msr_reg() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_machine_check()+0x192: call to mce_no_way_out() leaves .noinstr.text section
vmlinux.o: warning: objtool: mce_severity_amd.constprop.0()+0xca: call to mce_severity_amd_smca() leaves .noinstr.text section

$ x86_64-linux-gnu-gcc --version
x86_64-linux-gnu-gcc (Debian 11.2.0-9) 11.2.0
$ x86_64-linux-gnu-ld --version
GNU ld (GNU Binutils for Debian) 2.37

-- 
Cheers,
Stephen Rothwell