BSS not getting zeroed properly on my laptop?

[8infy]

Yes, if it was a problem, the assembler or linker would complain.

Thanks for the clarification.

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Is it possible for the s_sinks to lie outside of bss?

Below are the limits of the bss for a run:

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0xffffffff80126000 to 0xffffffff8012bb50

See below, which is very likely the Logger::initialize function comparing the s_sinks and s_write_lock resp.

One can see that it looks beyond the limits of bss for s_sinks - 0xffffffff8012bb58.

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ffffffff801179e2:	83 3d 6f 41 01 00 00 	cmpl   $0x0,0x1416f(%rip)        # 0xffffffff8012bb58
ffffffff801179e9:	48 89 e5             	mov    %rsp,%rbp
ffffffff801179ec:	41 56                	push   %r14
ffffffff801179ee:	41 55                	push   %r13
ffffffff801179f0:	41 54                	push   %r12
ffffffff801179f2:	53                   	push   %rbx
ffffffff801179f3:	0f 85 71 02 00 00    	jne    0xffffffff80117c6a
ffffffff801179f9:	48 83 3d 4f 41 01 00 	cmpq   $0x0,0x1414f(%rip)        # 0xffffffff8012bb50
ffffffff80117a00:	00 
ffffffff80117a01:	0f 85 44 02 00 00    	jne    0xffffffff80117c4b

The disassembly was generated by running the following on Kernel.bin. That is, the start of the Kernel.bin is at 0xffffffff80100000.

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objdump -b binary -D -m i386:x86-64 --adjust-vma=0xffffffff80100000

Edit:

Heh.

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0000000000000000 l    d  .bss._ZN6kernel6Logger7s_sinksE	0000000000000000 .bss._ZN6kernel6Logger7s_sinksE
0000000000000000  w    O .bss._ZN6kernel6Logger7s_sinksE	0000000000000008 _ZN6kernel6Logger7s_sinksE

You might want to try adding *(.bss.*) and/or *(.bss*), whichever is more general and allowed, to the linker script.

Wow, thanks for taking your time to look into this. So looks like my bss stuff is not actually in the bss section? Will try to rerun with this ld script fix and see if it works!

[8infy]

OMG! That was it! the section literally moved 16 bytes down and that was enough.... Thank you so much man
Now it boots successfully on that laptop
(You can submit a pull request if you want to get "official" credit for it, its you who found the problem after all)

[linuxyne]

OMG! That was it! the section literally moved 16 bytes down and that was enough.... Thank you so much man
Now it boots successfully on that laptop

Nice.

(You can submit a pull request if you want to get "official" credit for it, its you who found the problem after all)

Appreciate the offer, but that's alright.

[MichaelPetch]

This is only an addendum to a list of sections that may have subsections. `.text`and `.rodata`as well as `.bss`