Re: [LKP] Re: 28307d938f ("percpu: make pcpu_alloc() aware of current gfp .."): BUG: kernel reboot-without-warning in boot stage

[Li Zhijian]

On 6/2/20 8:18 PM, Filipe Manana wrote:
> On 02/06/20 05:37, Li Zhijian wrote:
> > Hi Filipe,
> >
> > LKP checked blow dmesg as the indicator in this problem
> >
> > > > [ÂÂÂ 0.144174] RAMDISK: [mem 0x7fa2e000-0x7fffffff]
> > > > [ÂÂÂ 0.144559] ACPI: Early table checksum verification disabled
> > > > [ÂÂÂ 0.144985] ACPI: RSDP 0x00000000000F5850 000014 (v00 BOCHS )
> > > > [ÂÂÂ 0.145424] ACPI: RSDT 0x00000000BFFE15C9 000030 (v01 BOCHS
> > > > BXPCRSDT 00000001 BXPC 00000001)
> > > > [ÂÂÂ 0.146051] ACPI: FACP 0x00000000BFFE149D 000074 (v01 BOCHS
> > > > BXPCFACP 00000001 BXPC 00000001)
> > > > BUG: kernel reboot-without-warning in boot stage
> > And i have reproduced it with script in attachment. this issue is gone
> > when i reverted this commit 28307d938f
> >
> > Please note that
> > - i reproduced it with kernel compiled by gcc-5
> > - i failed to reproduce it in kernel compiled by gcc-7 so far
> Odd.

Indeed !

i tested gcc-5 gcc-6 gcc-7, only gcc-5 triggered this issue, kernel 
built with gcc6 and gcc-7 works well

lizhijian@shao2-debian:~$ gcc-6 --version
gcc-6 (Debian 6.5.0-2) 6.5.0 20181026
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

lizhijian@shao2-debian:~$ gcc-5 --version
gcc-5 (Debian 5.5.0-12) 5.5.0 20171010
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

lizhijian@shao2-debian:~$ gcc-7 --version
gcc-7 (Debian 7.5.0-3) 7.5.0
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Thanks
Zhijian

> Here I tested with:
>
> $ gcc --version
> gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516
> Copyright (C) 2016 Free Software Foundation, Inc.