---------- Forwarded Message ----------
Subject: no bss cause strange values in insmod and ELF
Date: Wed, 9 May 2001 09:47:05 +0300
From: Shay Deloya <shay@jungo.com>
To: linux-mips@oss.sgi.com
Continuing my previous problem...
I have created a module with no bss , and compiled it with kernel 2.2.
Comparing this module with same code that has bss and acts OK.
Inserting the module with modutiles 2.2.2/ busybox insmod causes
a relocation overflow message , the reasons are:
1.in function obj_relocate: corrupted intsym->secidx value
(not the needed index in the ELF)
for some .text segments, other segments get their index value OK.
the ELF file seems to be OK.
2. in function arch_apply_relocation: the wrong index (secidx=1006a1e8)
cause R_MIPS_26 symbols (jump commands) to have the value of
obj_reloc_overflow and then causes relocation overflow.
Does anyone knows why same module that has a variable in bss acts fine
and the one without bss causes Relocation overflow in MIPS ? (in x86 there
is no problem).
Searching the code I see there is no initialization of the secidx ,
is it a problem of wrong reading of ELF files by insmod ?
Attached the two ELF files , and obj_relocate values.
Thanks,
Shay Deloya
______________________________________
Software Developer
Jungo - R&D
email: shay@jungo.com
web: http://www.jungo.com
Phone: 1-877-514-0537(USA) +972-9-8859365(Worldwide) ext. 221
Fax: 1-877-514-0538(USA) +972-9-8859366(Worldwide)
-------------------------------------------------------
--
Shay Deloya
______________________________________
Software Developer
Jungo - R&D
email: shayd@jungo.com
web: http://www.jungo.com
Phone: 1-877-514-0537(USA) +972-9-8859365(Worldwide) ext. 221
Fax: 1-877-514-0538(USA) +972-9-8859366(Worldwide)
ELF Header:
Magic: 7f 45 4c 46 01 02 01 00 00 00 00 00 00 00 00 00
Class: ELF32
Data: 2's complement, big endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: REL (Relocatable file)
Machine: MIPS R3000 big-endian
Version: 0x1
Entry point address: 0x0
Start of program headers: 0 (bytes into file)
Start of section headers: 4728 (bytes into file)
Flags: 0x10000001, noreorder, mips2
Size of this header: 52 (bytes)
Size of program headers: 0 (bytes)
Number of program headers: 0
Size of section headers: 40 (bytes)
Number of section headers: 15
Section header string table index: 12
Section Headers:
[Nr] Name Type Addr Off Size ES Flg Lk Inf Al
[ 0] NULL 00000000 000000 000000 00 0 0 0
[ 1] .text PROGBITS 00000000 000040 0005c0 00 AX 0 0 16
[ 2] .rel.text REL 00000000 001854 000518 08 13 1 4
[ 3] .data PROGBITS 00000000 000600 000050 00 WA 0 0 16
[ 4] .rel.data REL 00000000 001d6c 000038 08 13 3 4
[ 5] .bss NOBITS 00000000 000650 000000 00 WA 0 0 16
[ 6] .reginfo MIPS_REGINFO 00000000 000650 000018 01 A 0 0 4
[ 7] .mdebug MIPS_DEBUG 00000000 000668 000848 01 0 0 4
[ 8] .note NOTE 00000000 000eb0 000014 00 0 0 1
[ 9] .modinfo PROGBITS 00000000 000ec4 00001c 00 0 0 4
[10] .rodata PROGBITS 00000000 000ee0 0002f0 00 A 0 0 16
[11] .comment PROGBITS 00000000 0011d0 000035 00 0 0 1
[12] .shstrtab STRTAB 00000000 001205 000071 00 0 0 1
[13] .symtab SYMTAB 00000000 0014d0 000240 10 14 a 4
[14] .strtab STRTAB 00000000 001710 000141 00 0 0 1
There are no program headers in this file.
There is no dynamic segment in this file.
Relocation section '.rel.text' at offset 0x1854 contains 163 entries:
Offset Info Type Symbol's Value Symbol's Name
00000008 00205 R_MIPS_HI16 00000000 .text
0000000c 00206 R_MIPS_LO16 00000000 .text
00000028 00305 R_MIPS_HI16 00000000 .data
0000002c 00306 R_MIPS_LO16 00000000 .data
00000038 00305 R_MIPS_HI16 00000000 .data
0000003c 00306 R_MIPS_LO16 00000000 .data
00000048 00405 R_MIPS_HI16 00000000 .rodata
0000004c 00406 R_MIPS_LO16 00000000 .rodata
00000050 01c05 R_MIPS_HI16 00000000 printk
00000054 01c06 R_MIPS_LO16 00000000 printk
00000060 01d05 R_MIPS_HI16 00000000 __this_module
00000064 01d06 R_MIPS_LO16 00000000 __this_module
00000094 00204 R_MIPS_26 00000000 .text
0000009c 01d05 R_MIPS_HI16 00000000 __this_module
000000a0 01d06 R_MIPS_LO16 00000000 __this_module
000000ac 00405 R_MIPS_HI16 00000000 .rodata
000000b0 00406 R_MIPS_LO16 00000000 .rodata
000000b4 01c05 R_MIPS_HI16 00000000 printk
000000b8 01c06 R_MIPS_LO16 00000000 printk
000000c8 01e05 R_MIPS_HI16 00000000 atm_dev_deregister
000000cc 01e06 R_MIPS_LO16 00000000 atm_dev_deregister
000000d8 01f05 R_MIPS_HI16 00000000 kfree
000000dc 01f06 R_MIPS_LO16 00000000 kfree
000000e8 00305 R_MIPS_HI16 00000000 .data
000000ec 00306 R_MIPS_LO16 00000000 .data
000000f8 00405 R_MIPS_HI16 00000000 .rodata
000000fc 00406 R_MIPS_LO16 00000000 .rodata
00000100 01c05 R_MIPS_HI16 00000000 printk
00000104 01c06 R_MIPS_LO16 00000000 printk
00000120 00305 R_MIPS_HI16 00000000 .data
00000124 00306 R_MIPS_LO16 00000000 .data
0000013c 00405 R_MIPS_HI16 00000000 .rodata
00000140 00406 R_MIPS_LO16 00000000 .rodata
00000144 01c05 R_MIPS_HI16 00000000 printk
00000148 01c06 R_MIPS_LO16 00000000 printk
00000158 02005 R_MIPS_HI16 00000000 kmalloc
0000015c 02006 R_MIPS_LO16 00000000 kmalloc
00000174 00405 R_MIPS_HI16 00000000 .rodata
00000178 00406 R_MIPS_LO16 00000000 .rodata
0000017c 01c05 R_MIPS_HI16 00000000 printk
00000180 01c06 R_MIPS_LO16 00000000 printk
0000018c 00204 R_MIPS_26 00000000 .text
00000194 00405 R_MIPS_HI16 00000000 .rodata
00000198 00406 R_MIPS_LO16 00000000 .rodata
000001a0 00305 R_MIPS_HI16 00000000 .data
000001a4 00306 R_MIPS_LO16 00000000 .data
000001a8 02105 R_MIPS_HI16 00000000 atm_dev_register
000001ac 02106 R_MIPS_LO16 00000000 atm_dev_register
000001c8 00205 R_MIPS_HI16 00000000 .text
000001cc 00206 R_MIPS_LO16 00000000 .text
000001d4 02305 R_MIPS_HI16 00000000 request_irq
000001d8 02306 R_MIPS_LO16 00000000 request_irq
000001ec 00405 R_MIPS_HI16 00000000 .rodata
000001f0 00406 R_MIPS_LO16 00000000 .rodata
000001f4 01c05 R_MIPS_HI16 00000000 printk
000001f8 01c06 R_MIPS_LO16 00000000 printk
00000204 00204 R_MIPS_26 00000000 .text
0000020c 00305 R_MIPS_HI16 00000000 .data
00000210 00306 R_MIPS_LO16 00000000 .data
00000214 00305 R_MIPS_HI16 00000000 .data
00000218 00306 R_MIPS_LO16 00000000 .data
00000224 00405 R_MIPS_HI16 00000000 .rodata
00000228 00406 R_MIPS_LO16 00000000 .rodata
0000022c 01c05 R_MIPS_HI16 00000000 printk
00000230 01c06 R_MIPS_LO16 00000000 printk
00000254 00305 R_MIPS_HI16 00000000 .data
00000258 00306 R_MIPS_LO16 00000000 .data
00000268 00405 R_MIPS_HI16 00000000 .rodata
0000026c 00406 R_MIPS_LO16 00000000 .rodata
00000270 01c05 R_MIPS_HI16 00000000 printk
00000274 01c06 R_MIPS_LO16 00000000 printk
00000280 00305 R_MIPS_HI16 00000000 .data
00000284 00306 R_MIPS_LO16 00000000 .data
00000290 00405 R_MIPS_HI16 00000000 .rodata
00000294 00406 R_MIPS_LO16 00000000 .rodata
00000298 01c05 R_MIPS_HI16 00000000 printk
0000029c 01c06 R_MIPS_LO16 00000000 printk
000002b8 00305 R_MIPS_HI16 00000000 .data
000002bc 00306 R_MIPS_LO16 00000000 .data
000002cc 00405 R_MIPS_HI16 00000000 .rodata
000002d0 00406 R_MIPS_LO16 00000000 .rodata
000002d4 01c05 R_MIPS_HI16 00000000 printk
000002d8 01c06 R_MIPS_LO16 00000000 printk
000002e4 00305 R_MIPS_HI16 00000000 .data
000002e8 00306 R_MIPS_LO16 00000000 .data
000002f4 00405 R_MIPS_HI16 00000000 .rodata
000002f8 00406 R_MIPS_LO16 00000000 .rodata
000002fc 01c05 R_MIPS_HI16 00000000 printk
00000300 01c06 R_MIPS_LO16 00000000 printk
00000318 00305 R_MIPS_HI16 00000000 .data
0000031c 00306 R_MIPS_LO16 00000000 .data
0000032c 00405 R_MIPS_HI16 00000000 .rodata
00000330 00406 R_MIPS_LO16 00000000 .rodata
00000334 01c05 R_MIPS_HI16 00000000 printk
00000338 01c06 R_MIPS_LO16 00000000 printk
00000348 01d05 R_MIPS_HI16 00000000 __this_module
0000034c 01d06 R_MIPS_LO16 00000000 __this_module
00000368 00305 R_MIPS_HI16 00000000 .data
0000036c 00306 R_MIPS_LO16 00000000 .data
0000037c 00405 R_MIPS_HI16 00000000 .rodata
00000380 00406 R_MIPS_LO16 00000000 .rodata
00000384 01c05 R_MIPS_HI16 00000000 printk
00000388 01c06 R_MIPS_LO16 00000000 printk
000003a4 00305 R_MIPS_HI16 00000000 .data
000003a8 00306 R_MIPS_LO16 00000000 .data
000003b8 00405 R_MIPS_HI16 00000000 .rodata
000003bc 00406 R_MIPS_LO16 00000000 .rodata
000003c0 01c05 R_MIPS_HI16 00000000 printk
000003c4 01c06 R_MIPS_LO16 00000000 printk
000003d4 01d05 R_MIPS_HI16 00000000 __this_module
000003d8 01d06 R_MIPS_LO16 00000000 __this_module
000003f4 00305 R_MIPS_HI16 00000000 .data
000003f8 00306 R_MIPS_LO16 00000000 .data
00000408 00405 R_MIPS_HI16 00000000 .rodata
0000040c 00406 R_MIPS_LO16 00000000 .rodata
00000410 01c05 R_MIPS_HI16 00000000 printk
00000414 01c06 R_MIPS_LO16 00000000 printk
0000042c 00305 R_MIPS_HI16 00000000 .data
00000430 00306 R_MIPS_LO16 00000000 .data
00000440 00405 R_MIPS_HI16 00000000 .rodata
00000444 00406 R_MIPS_LO16 00000000 .rodata
00000448 01c05 R_MIPS_HI16 00000000 printk
0000044c 01c06 R_MIPS_LO16 00000000 printk
00000458 00305 R_MIPS_HI16 00000000 .data
0000045c 00306 R_MIPS_LO16 00000000 .data
00000468 00405 R_MIPS_HI16 00000000 .rodata
0000046c 00406 R_MIPS_LO16 00000000 .rodata
00000470 01c05 R_MIPS_HI16 00000000 printk
00000474 01c06 R_MIPS_LO16 00000000 printk
00000490 00305 R_MIPS_HI16 00000000 .data
00000494 00306 R_MIPS_LO16 00000000 .data
000004a4 00405 R_MIPS_HI16 00000000 .rodata
000004a8 00406 R_MIPS_LO16 00000000 .rodata
000004ac 01c05 R_MIPS_HI16 00000000 printk
000004b0 01c06 R_MIPS_LO16 00000000 printk
000004bc 00305 R_MIPS_HI16 00000000 .data
000004c0 00306 R_MIPS_LO16 00000000 .data
000004cc 00405 R_MIPS_HI16 00000000 .rodata
000004d0 00406 R_MIPS_LO16 00000000 .rodata
000004d4 01c05 R_MIPS_HI16 00000000 printk
000004d8 01c06 R_MIPS_LO16 00000000 printk
000004f4 00305 R_MIPS_HI16 00000000 .data
000004f8 00306 R_MIPS_LO16 00000000 .data
0000050c 00405 R_MIPS_HI16 00000000 .rodata
00000510 00406 R_MIPS_LO16 00000000 .rodata
00000514 01c05 R_MIPS_HI16 00000000 printk
00000518 01c06 R_MIPS_LO16 00000000 printk
00000524 00305 R_MIPS_HI16 00000000 .data
00000528 00306 R_MIPS_LO16 00000000 .data
00000534 00405 R_MIPS_HI16 00000000 .rodata
0000053c 00406 R_MIPS_LO16 00000000 .rodata
00000550 00305 R_MIPS_HI16 00000000 .data
00000554 00306 R_MIPS_LO16 00000000 .data
00000564 00405 R_MIPS_HI16 00000000 .rodata
00000568 00406 R_MIPS_LO16 00000000 .rodata
0000056c 01c05 R_MIPS_HI16 00000000 printk
00000570 01c06 R_MIPS_LO16 00000000 printk
0000057c 00305 R_MIPS_HI16 00000000 .data
00000580 00306 R_MIPS_LO16 00000000 .data
0000058c 00405 R_MIPS_HI16 00000000 .rodata
00000590 00406 R_MIPS_LO16 00000000 .rodata
00000594 01c05 R_MIPS_HI16 00000000 printk
00000598 01c06 R_MIPS_LO16 00000000 printk
Relocation section '.rel.data' at offset 0x1d6c contains 7 entries:
Offset Info Type Symbol's Value Symbol's Name
00000008 00202 R_MIPS_32 00000000 .text
0000000c 00202 R_MIPS_32 00000000 .text
00000010 00202 R_MIPS_32 00000000 .text
0000001c 00202 R_MIPS_32 00000000 .text
00000028 00202 R_MIPS_32 00000000 .text
0000002c 00202 R_MIPS_32 00000000 .text
0000003c 00202 R_MIPS_32 00000000 .text
Symbol table '.symtab' contains 36 entries:
Num: Value Size Type Bind Ot Ndx Name
0: 0 0 NOTYPE LOCAL 0 UND
1: 0 0 SECTION LOCAL 0 9
2: 0 0 SECTION LOCAL 0 1 text
3: 0 0 SECTION LOCAL 0 3 data
4: 0 0 SECTION LOCAL 0 10 rodata
5: 0 0 SECTION LOCAL 0 5 bss
6: 0 0 SECTION LOCAL 0 6
7: 0 0 SECTION LOCAL 0 7
8: 0 0 SECTION LOCAL 0 8
9: 0 0 SECTION LOCAL 0 11
10: 0 0 NOTYPE LOCAL 0 1 gcc2_compiled.
11: 0 0 NOTYPE LOCAL 0 1 __gnu_compiled_c
12: 0 28 OBJECT GLOBAL 0 9 __module_kernel_version
13: 0 4 OBJECT LOCAL 0 10 _bonito
14: 0 4 OBJECT LOCAL 0 3 display_string
15: 4 60 OBJECT LOCAL 0 3 atm_ops
16: 318 140 FUNC LOCAL 0 1 idd_open
17: 3a4 136 FUNC LOCAL 0 1 idd_close
18: 490 100 FUNC LOCAL 0 1 idd_ioctl
19: 254 100 FUNC LOCAL 0 1 idd_send
20: 4f4 92 FUNC LOCAL 0 1 idd_phy_put
21: 550 100 FUNC LOCAL 0 1 idd_phy_get
22: 42c 100 FUNC LOCAL 0 1 idd_proc_read
23: 40 4 OBJECT GLOBAL 0 3 the_card
24: 44 4 OBJECT GLOBAL 0 3 dbg_lvl
25: 0 40 FUNC GLOBAL 0 1 init_module
26: 120 308 FUNC LOCAL 0 1 idd_init_card
27: 28 248 FUNC GLOBAL 0 1 cleanup_module
28: 0 0 OBJECT GLOBAL 0 UND printk
29: 0 0 OBJECT GLOBAL 0 UND __this_module
30: 0 0 OBJECT GLOBAL 0 UND atm_dev_deregister
31: 0 0 OBJECT GLOBAL 0 UND kfree
32: 0 0 OBJECT GLOBAL 0 UND kmalloc
33: 0 0 OBJECT GLOBAL 0 UND atm_dev_register
34: 2b8 96 FUNC LOCAL 0 1 idd_irq_handler
35: 0 0 OBJECT GLOBAL 0 UND request_irq
No version information found in this file.
Values of intsym in obj_relocate , just before the call to obj_symbol_final_value function
==========================================================================================
NO BSS Relocation overflow
==========================
obj_relocate: baseaddr=c0015000 relocation all sections with this addr
obj_relocate: section=.symtab relend=268866256
obj_relocate: intsym->name=.text,symndx=2 intsym->secidx=1006a1e8
obj_relocate: intsym->name=.text,symndx=2 intsym->secidx=1006a1e8
obj_relocate: intsym->name=.data,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=.data,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=.data,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=.data,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=.rodata,symndx=4 intsym->secidx=a
obj_relocate: intsym->name=.rodata,symndx=4 intsym->secidx=a
obj_relocate: intsym->name=printk,symndx=28 intsym->secidx=10000
obj_relocate: intsym->name=printk,symndx=28 intsym->secidx=10000
obj_relocate: intsym->name=__this_module,symndx=29 intsym->secidx=f
obj_relocate: intsym->name=__this_module,symndx=29 intsym->secidx=f
obj_relocate: intsym->name=.text,symndx=2 intsym->secidx=1006a1e8
With BSS good execution
=======================
obj_relocate: section=.symtab relend=268866256
obj_relocate: intsym->name=.text,symndx=2 intsym->secidx=1
obj_relocate: intsym->name=.text,symndx=2 intsym->secidx=1
obj_relocate: intsym->name=,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=,symndx=3 intsym->secidx=3
obj_relocate: intsym->name=.rodata,symndx=4 intsym->secidx=a
obj_relocate: intsym->name=.rodata,symndx=4 intsym->secidx=a
obj_relocate: intsym->name=printk,symndx=27 intsym->secidx=10000
obj_relocate: intsym->name=printk,symndx=27 intsym->secidx=10000
obj_relocate: intsym->name=__this_module,symndx=28 intsym->secidx=f
obj_relocate: intsym->name=__this_module,symndx=28 intsym->secidx=f
obj_relocate: intsym->name=.text,symndx=2 intsym->secidx=1
