Re: C200, 712/80: strange sysfs issues with Linux 4.18.0-1-parisc

Re: C200, 712/80: strange sysfs issues with Linux 4.18.0-1-parisc

[Helge Deller]

On 28.11.18 16:26, Frank Scheiner wrote:
> I'm experiencing some strange issues on both a C200 and a 712/80 with
> the current 32 bit SP kernel (4.18.0-2.parisc (4.18.10-2)). This does
> not happen when using the 64 bit MP kernel of the same version on a
> rp3440 for example.
> 
> For every module loaded I get a message similar to the following example:
> [...]
> [   47.799100] sysfs: cannot create duplicate filename '/module/nfs/sections/.text'
> [   47.887396] CPU: 0 PID: 98 Comm: modprobe Not tainted 4.18.0-2-parisc #1 Debian 4.18.10-2
> [   47.984894] Backtrace:
> [   48.013164]  [<1017ce2c>] show_stack+0x3c/0x50
> [   48.066177]  [<107a7210>] dump_stack+0x28/0x38
> [   48.119192]  [<103f900c>] sysfs_warn_dup+0x88/0xac
> [   48.176329]  [<103f8b1c>] sysfs_add_file_mode_ns+0x164/0x1d0
> [   48.243832]  [<103f9e70>] internal_create_group+0x11c/0x304
> [   48.310277]  [<103fa0a0>] sysfs_create_group+0x48/0x60
> [   48.371571]  [<1022abe8>] load_module.constprop.35+0x1f9c/0x23b8
> [   48.443200]  [<1022b278>] sys_finit_module+0xd0/0x11c
> [   48.503468]  [<101831dc>] syscall_exit+0x0/0x14

I think it happens because I disabled building the kernel with the "-ffunction-sections" compiler option.
The relevant patch was included in kernel 4.18:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=24b6c22504a27210a8377e54d24d425ae414f2c1

On kernel 4.17 I see:

./4.17.0-3-parisc-smp/kernel/drivers/net/ethernet/intel/e1000/e1000.ko:     file format elf32-hppa-linux
Sections:
Idx Name          Size      VMA       LMA       File off  Algn
   0 .note.gnu.build-id 00000024  00000000  00000000  00000034  2**2
                   CONTENTS, ALLOC, LOAD, READONLY, DATA
   1 .text         00000000  00000000  00000000  00000058  2**0
                   CONTENTS, ALLOC, LOAD, READONLY, CODE
   2 .text.e1000_alloc_dummy_rx_buffers 0000002c  00000000  00000000  00000058  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   3 .text.e1000_fix_features 00000074  00000000  00000000  00000084  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   4 .text.unlikely.e1000_regdump 0000049c  00000000  00000000  000000f8  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   5 .text.e1000_setup_rctl 00000144  00000000  00000000  00000594  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   6 .text.e1000_configure_rx 000002a0  00000000  00000000  000006d8  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE


On kernel 4.18 I get:
./4.18.0-3-parisc-smp/kernel/drivers/net/ethernet/intel/e1000/e1000.ko:     file format elf32-hppa-linux

Sections:
Idx Name          Size      VMA       LMA       File off  Algn
   0 .note.gnu.build-id 00000024  00000000  00000000  00000034  2**2
                   CONTENTS, ALLOC, LOAD, READONLY, DATA
   1 .text         0000a550  00000000  00000000  00000058  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   2 .text.unlikely 0000078c  00000000  00000000  0000a5a8  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   3 .init.text    000000cc  00000000  00000000  0000ad34  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   4 .exit.text    00000030  00000000  00000000  0000ae00  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   5 .text         00007848  00000000  00000000  0000ae30  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   6 .text         00004298  00000000  00000000  00012678  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   7 .text         00000c8c  00000000  00000000  00016910  2**2
                   CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
   8 .text         00000000  00000000  00000000  0001759c  2**0
                   CONTENTS, ALLOC, LOAD, READONLY, CODE

As can be seen, we now get multiple sections all named ".text" which is what triggers the kernel warning.

It seems we need to revert the patch, or find a way that the compiler doesn't produce multiple .text sections...?

Helge