Re: Bug: broken /proc/kcore in 6.13
From: Alexandre Ferrieux
Date: Fri Jan 17 2025 - 10:28:51 EST
On 17/01/2025 16:19, Alexandre Ferrieux wrote:
> On 17/01/2025 15:44, Lorenzo Stoakes wrote:
>>> Alexandre Ferrieux <alexandre.ferrieux@xxxxxxxxx> wrote:
>>>
>>>> Hi,
>>>>
>>>> Somewhere in the 6.13 branch (not bisected yet, sorry), it stopped being
>>>> possible to disassemble the running kernel from gdb through /proc/kcore.
>> Thanks for the report! Much appreciated.
>>
>> I may try to bisect here also unless you're close to finding the commit that
>> broke this?
>
> I'm currently homing in on copy_page_to_iter_nofault(), will report shortly :)
Hmm, actually, that baby ain't cooperative:
[Fri Jan 17 15:23:05 2025] trace_kprobe: Could not probe notrace function
copy_page_to_iter_nofault
... if I cannot insert kprobes to sniff around, I'm a bit stuck :}
So I think you'll reach the goal faster than me !
PS: For your bisection: the last working kernel I know of is Debian's 6.12 final:
ii linux-image-6.12.9-amd64 6.12.9-1 amd64
Linux 6.12 for 64-bit PCs (signed)