Re: Kernel Oops on alpha with kernel version >=6.9.x

[Michael Cree <mcree@orcon.net.nz>]

On Mon, Dec 09, 2024 at 09:05:46AM +0100, Magnus Lindholm wrote:
> > Maybe, maybe not.  Building 6.11.11 with alpha-linux-gnu-gcc-9
> > (Debian 9.3.0-22) fixed the null pointer access in the scsi
> > subsystem, and finally I have a bootable system! (Tested on ES45.)
> > But I now get a null pointer access when network driver loaded:
> 
> Very interesting! Can you provide a full stack dump? interested to
> see if this is the same issue as on my system.

[   33.144514] e100 0001:02:04.0 enP1p2s4: NIC Link is Up 100 Mbps Full Duplex
[   36.878887] Unable to handle kernel paging request at virtual address 0000000000000000
[   36.879863] CPU 0 
[   36.879863] kworker/0:1(10): Oops -1
[   36.881817] pc = [<0000000000000000>]  ra = [<0000000000000001>]  ps = 0000    Not tainted
[   36.882793] pc is at 0x0
[   36.883770] ra is at 0x1
[   36.884746] v0 = 0000000000000007  t0 = 0000000000000001  t1 = fffffc000091cc80
[   36.884746] t2 = 0000000000000000  t3 = fffffc00040cca40  t4 = 0000000000000001
[   36.884746] t5 = 0000000000000001  t6 = 0000000000000000  t7 = fffffc0004124000
[   36.884746] s0 = fffffc000a037e00  s1 = fffffc000a037f28  s2 = fffffffffffffed8
[   36.884746] s3 = fffffc0004020b40  s4 = fffffc0001c8d688  s5 = fffffc0004020bc0
[   36.884746] s6 = fffffc0001c8d680
[   36.884746] a0 = fffffc0001c5b320  a1 = fffffc000ac14200  a2 = fffffc00040ccac0
[   36.884746] a3 = fffffc0003df36c0  a4 = fffffc000dfb3d38  a5 = ffffffffffffffff
[   36.884746] t8 = 0000000000000000  t9 = 0000000000000000  t10= 0000000000000001
[   36.884746] t11= 0000000000000001  pv = fffffc00018b7180  at = 0000000000000001
[   36.884746] gp = fffffc0001cb08c8  sp = 00000000ab1ca88d
[   36.884746] Disabling lock debugging due to kernel taint
[   36.896465] Trace:
[   36.896465] [<fffffc0001049c8c>] process_scheduled_works+0xdc/0x420
[   36.898418] [<fffffc000104a740>] worker_thread+0x0/0x3d0
[   36.899395] [<fffffc000104a8f0>] worker_thread+0x1b0/0x3d0
[   36.900371] [<fffffc000104a740>] worker_thread+0x0/0x3d0
[   36.901348] [<fffffc000105705c>] kthread+0x17c/0x1c0
[   36.902324] [<fffffc000104a740>] worker_thread+0x0/0x3d0
[   36.903301] [<fffffc0001011198>] ret_from_kernel_thread+0x18/0x20
[   36.904277] [<fffffc0001056ee0>] kthread+0x0/0x1c0
[   36.905254] [<fffffc0001011180>] ret_from_kernel_thread+0x0/0x20

[   36.907207] Code:
[   36.907207]  00000000 
[   36.908184]  00000000 
[   36.909160]  00063301 
[   36.910137]  00000e90 
[   36.911113]  00001111 
[   36.912090]  0000795c 

> Have you tried passing rcupdate.rcu_normal=1 as boot parameter
> to the kernel? That allowed me to bypass the network interface
> problem on my system.

Haven't as yet, but backtrace above does not go through rcu routines.
Maybe I am seeing a different issue.

Cheers,
Michael.