Compiling kernel-3.4.xxx with gcc-9.x. Need some help.

[Fawad Lateef]

Hi Greg,

(Sending again as seems like I had rich-text available by mistake, so
likely my message is rejected)


On Tue, 30 Mar 2021 at 15:40, Greg KH <greg at kroah.com> wrote:
>
> On Tue, Mar 30, 2021 at 03:23:10PM +0200, Fawad Lateef wrote:
> > So can I still use kernel-3.4 compiled with gcc-5.5, and boot full
> > user-space with gcc-9.1?
>
> Yes, of course.
>
> > I was expecting it to be possible but might not work due to
> > incompatibility? As I know that when I tried to compile buildroot-2019
> > (with latest version of openssl and others) it needs kernel headers
> > and then I likely can't use 3.4 kernel.
>
> buildroot might be different, as that is how you are building your whole
> system, but there is no dependency on the kernel and userspace to use
> the same version of the compiler.  Otherwise everyone would have to
> rebuild the world for every time they updated their kernel, this isn't
> the BSDs :)
>

I tried booting the userspace compiled with gcc-9.1 and kernel
compiled with gcc-5.5. But seems like the kernel 3.4.111 is not
compatible with user-space compiled with gcc-9.1.
During boot getting error: "FATAL: kernel too old." (from init I
believe) and then kernel Panics. Log (part) below:

------
[   26.242878] registered taskstats version 1
[   26.247522] axp20_buck3: incomplete constraints, leaving on
[   26.253314] axp20_buck2: incomplete constraints, leaving on
[   26.259161] axp20_ldo4: incomplete constraints, leaving on
[   26.264877] axp20_ldo3: incomplete constraints, leaving on
[   26.270581] axp20_ldo2: incomplete constraints, leaving on
[   26.276299] axp20_ldo1: incomplete constraints, leaving on
[   26.282059] sunxi-rtc sunxi-rtc: setting system clock to 2010-01-01
00:00:00 UTC (1262304000)
[   26.291136] Freeing init memory: 160K
FATAL: kernel too old
[   26.308118] usb 3-1.1: New USB device found, idVendor=148f, idProduct=5572
[   26.315022] usb 3-1.1: New USB device strings: Mfr=1, Product=2,
SerialNumber=3
[   26.322322] usb 3-1.1: Product: 802.11 n WLAN
[   26.326730] usb 3-1.1: Manufacturer: Ralink
[   26.330908] usb 3-1.1: SerialNumber: 1.0
[   26.335055] Kernel panic - not syncing: Attempted to kill init!
exitcode=0x00007f00
[   26.335061]
[   26.344221] [<c0011285>] (unwind_backtrace+0x1/0x90) from
[<c02bdc4f>] (panic+0x6f/0x15c)
[   26.352400] [<c02bdc4f>] (panic+0x6f/0x15c) from [<c0031fc7>]
(do_exit+0x5ff/0x600)
[   26.360057] [<c0031fc7>] (do_exit+0x5ff/0x600) from [<c0032009>]
(do_group_exit+0x25/0x78)
[   26.368318] [<c0032009>] (do_group_exit+0x25/0x78) from
[<c0032069>] (__wake_up_parent+0x1/0x18)
[   26.377101] [<c0032069>] (__wake_up_parent+0x1/0x18) from
[<c000ca81>] (ret_fast_syscall+0x1/0x44)
[   26.386064] CPU1: stopping
[   26.388781] [<c0011285>] (unwind_backtrace+0x1/0x90) from
[<c0010707>] (handle_IPI+0x157/0x170)
[   26.397477] [<c0010707>] (handle_IPI+0x157/0x170) from [<c0008393>]
(gic_handle_irq+0x3f/0x40)
[   26.406085] [<c0008393>] (gic_handle_irq+0x3f/0x40) from
[<c000c65b>] (__irq_svc+0x3b/0x5c)
[   26.414427] Exception stack(0xef065f88 to 0xef065fd0)
[   26.419476] 5f80:                   ffffffed 00000001 1037d000
00000000 ef064000 c04d3c08
[   26.427648] 5fa0: ef064000 ef064000 c04a9a10 ef064018 00000000
00000000 3b9aca00 ef065fd0
[   26.435817] 5fc0: c000d469 c000d46a 60000033 ffffffff
[   26.440870] [<c000c65b>] (__irq_svc+0x3b/0x5c) from [<c000d46a>]
(default_idle+0x1a/0x1c)
[   26.449048] [<c000d46a>] (default_idle+0x1a/0x1c) from [<c000d6c1>]
(cpu_idle+0x91/0x98)
[   26.457135] [<c000d6c1>] (cpu_idle+0x91/0x98) from [<40480bd9>] (0x40480bd9)
[   26.464181] Rebooting in 10 seconds..
[   36.444472] Restarting Linux version 3.4.113
(flateef at flateef-XPS-13-9360) (gcc version 5.5.0 (Buildroot
2016.02-00152-g83a8d925e-dirty) ) #1 SMP Wed Mar 24 00:29:58 CET 2021
[   36.444482]

-----------------------------------------------------

Can I do something to make them work together?

Thanks

Fawad Lateef

> thanks,
>
> greg k-h