[PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

Hello,

The latest Git kernel doesn't boot anymore on our e5500 machines (QEMU, 
X5000, Mirari etc) after the PowerPC updates 6.19-1. [1]

Error messages (QEMU e5500 VM):

Bad kernel stack pointer 4d694c01a88270 at c0000000000003bc
Oops: Bad kernel stack pointer, sig: 6 [#1]
BE PAGE_SIZE=4K  SMP NR_CPUS=4 QEMU e500
Modules linked in:
CPU: 2 UID: 0 PID: 2788 Comm: udevd Not tainted 
6.19.0-a4-powerpc64-smp-g416f99c3b16f-dirty #1 VOLUNTARY
Hardware name: QEMU ppce500 e5500 0x80240012 QEMU e500
NIP:  c0000000000003bc LR: 0000000000230760 CTR: 0000000000230754
REGS: c00000003ff9bd20 TRAP: 0300   Not tainted 
(6.19.0-a4-powerpc64-smp-g416f99c3b16f-dirty)
MSR:  0000000090029000 <CE,EE,ME>  CR: 48842888  XER: 20000000
DEAR: 004d694c01a882f0 ESR: 0000000000000000 IRQMASK: 1
GPR00: 01a56ad000000000 004d694c01a88270 ffd86ca00046c958 ffd86c89ffffffff
GPR04: 0000000000000000 00000000ffffffff 0000000000000000 0000000000000007
GPR08: 000000000037a60c 0000000000000000 0000000000000000 0000000000230754
GPR12: 0000000004000000 c00000003fff7900 0000000000000004 0000000001a88270
GPR16: 00000000020397f0 0000000000bc287c 00000000004d009c 0000000000000000
GPR20: 0000000000000000 0000000000000000 00000000ffd86d5c 0000000001a4a130
GPR24: 00000000004d0040 00000000ffd86bdc 0000000000000000 00000000ffd86ab4
GPR28: 00000000004d009c 0000000001a807e0 0000000000379fc0 0000000001a84b50
NIP [c0000000000003bc] interrupt_return_srr_user+0x80/0xf4
LR [0000000000230760] 0x230760
Call Trace:
Code: 38000000 e8e100a8 e90100b0 e92100b8 e94100c0 e96100c8 e98100d0 
e9a100d8 7c6ff120 7c8803a6 7ca903a6 7cc103a6 <e8410080> e8610088 
e8810090 e8a10098
---[ end trace 0000000000000000 ]---

note: udevd[2788] exited with irqs disabled

---

Please check the PowerPC updates 6.19-1. [1]

You can check it yourself with QEMU. ;-)

Thanks,
Christian


[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ad952db4a865e96ec98d4c5874a4699fe3286d56

-- 
Sent with BrassMonkey 33.9.1 (https://github.com/chzigotzky/Web-Browsers-and-Suites-for-Linux-PPC/releases/tag/BrassMonkey_33.9.1)

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Gautam Menghani]

Hi Christian,

Thanks for the report. Can you also please share the QEMU command line
you were using? That would be helpful.

Thanks,
Gautam

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

> On 08 December 2025 at 06:51 am, Gautam Menghani <gautam@linux.ibm.com> wrote:
> 
> Hi Christian,
> 
> Thanks for the report. Can you also please share the QEMU command line
> you were using? That would be helpful.
> 
> Thanks,
> Gautam

Hi Gautam,

Here is the command line:

qemu-system-ppc64 -M ppce500 -cpu e5500 -m 1024 -kernel uImage -drive format=raw,file=void-live-powerpc-20230317.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-gpu-pci -device virtio-mouse-pci -device virtio-keyboard-pci -device pci-ohci,id=newusb -audiodev id=sndbe,driver=pa,server=/run/user/1000/pulse/native -device usb-audio,bus=newusb.0 -enable-kvm -smp 4 -fsdev local,security_model=passthrough,id=fsdev0,path=/home/amigaone/Music -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=hostshare -display gtk

Thanks,
Christian

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christophe Leroy (CS GROUP)]

Hello,

Le 07/12/2025 à 17:17, Christian Zigotzky a écrit :
> Hello,
> 
> The latest Git kernel doesn't boot anymore on our e5500 machines (QEMU, 
> X5000, Mirari etc) after the PowerPC updates 6.19-1. [1]
> 
> Error messages (QEMU e5500 VM):
> 
> Bad kernel stack pointer 4d694c01a88270 at c0000000000003bc
> Oops: Bad kernel stack pointer, sig: 6 [#1]
> BE PAGE_SIZE=4K  SMP NR_CPUS=4 QEMU e500
> Modules linked in:
> CPU: 2 UID: 0 PID: 2788 Comm: udevd Not tainted 6.19.0-a4-powerpc64-smp- 
> g416f99c3b16f-dirty #1 VOLUNTARY
> Hardware name: QEMU ppce500 e5500 0x80240012 QEMU e500
> NIP:  c0000000000003bc LR: 0000000000230760 CTR: 0000000000230754
> REGS: c00000003ff9bd20 TRAP: 0300   Not tainted (6.19.0-a4-powerpc64- 
> smp-g416f99c3b16f-dirty)
> MSR:  0000000090029000 <CE,EE,ME>  CR: 48842888  XER: 20000000
> DEAR: 004d694c01a882f0 ESR: 0000000000000000 IRQMASK: 1
> GPR00: 01a56ad000000000 004d694c01a88270 ffd86ca00046c958 ffd86c89ffffffff
> GPR04: 0000000000000000 00000000ffffffff 0000000000000000 0000000000000007
> GPR08: 000000000037a60c 0000000000000000 0000000000000000 0000000000230754
> GPR12: 0000000004000000 c00000003fff7900 0000000000000004 0000000001a88270
> GPR16: 00000000020397f0 0000000000bc287c 00000000004d009c 0000000000000000
> GPR20: 0000000000000000 0000000000000000 00000000ffd86d5c 0000000001a4a130
> GPR24: 00000000004d0040 00000000ffd86bdc 0000000000000000 00000000ffd86ab4
> GPR28: 00000000004d009c 0000000001a807e0 0000000000379fc0 0000000001a84b50
> NIP [c0000000000003bc] interrupt_return_srr_user+0x80/0xf4
> LR [0000000000230760] 0x230760
> Call Trace:
> Code: 38000000 e8e100a8 e90100b0 e92100b8 e94100c0 e96100c8 e98100d0 
> e9a100d8 7c6ff120 7c8803a6 7ca903a6 7cc103a6 <e8410080> e8610088 
> e8810090 e8a10098
> ---[ end trace 0000000000000000 ]---
> 
> note: udevd[2788] exited with irqs disabled
> 
> ---
> 
> Please check the PowerPC updates 6.19-1. [1]
> 
> You can check it yourself with QEMU. ;-)
> 

I tried today's Linux tree (commit 
c2f2b01b74be8b40a2173372bcd770723f87e7b2 (HEAD, linus/master, 
linus/HEAD)) with corenet64_smp_defconfig and I have no problem booting 
on QEMU, see below. Can you provide more details on your problem, the 
full messages before the Oops, and your .config ?

Thanks
Christophe

chleroy@PO20335:~/linux-powerpc$ qemu-system-ppc64 -smp 4 -nographic -M 
ppce500 -cpu e5500 -m 1G -kernel 
/home/chleroy/linux-powerpc/arch/powerpc/boot/uImage  -initrd 
./qemu/rootfs.cpio.gz -append "noreboot no_hash_pointers" -s $* -netdev 
user,id=mynet,tftp=/var/lib/tftpboot -device e1000,netdev=mynet

random: crng init done
Hash pointers mode set to never.
Activating Kernel Userspace Access Protection
Activating Kernel Userspace Execution Prevention
MMU: Supported page sizes
          4 KB as direct
       4096 KB as direct
      16384 KB as direct
      65536 KB as direct
     262144 KB as direct
    1048576 KB as direct
MMU: Book3E HW tablewalk not supported
Linux version 6.18.0-12356-gc2f2b01b74be 
(chleroy@PO20335.IDSI0.si.c-s.fr) (powerpc64-linux-gcc (GCC) 8.5.0, GNU 
ld (GNU Binutils) 2.36.1) #1786 SMP Mon Dec  8 08:15:29 CET 2025
OF: reserved mem: Reserved memory: No reserved-memory node in the DT
Found initrd at 0xc000000004000000:0xc0000000041d1a3b
Hardware name: QEMU ppce500 e5500 0x80240020 QEMU e500
printk: legacy bootconsole [udbg0] enabled
CPU maps initialized for 1 thread per core
-----------------------------------------------------
phys_mem_size     = 0x40000000
dcache_bsize      = 0x40
icache_bsize      = 0x40
cpu_features      = 0x0000000300800194
   possible        = 0x0000000300900394
   always          = 0x0000000300800394
cpu_user_features = 0xcc008000 0x08000000
mmu_features      = 0x000a0010
firmware_features = 0x0000000000000000
-----------------------------------------------------
qemu_e500_setup_arch()
barrier-nospec: using isync; sync as speculation barrier
Zone ranges:
   DMA      [mem 0x0000000000000000-0x000000003fffffff]
   Normal   empty
Movable zone start for each node
Early memory node ranges
   node   0: [mem 0x0000000000000000-0x000000003fffffff]
Initmem setup node 0 [mem 0x0000000000000000-0x000000003fffffff]
MMU: Allocated 2112 bytes of context maps for 255 contexts
percpu: Embedded 27 pages/cpu s71896 r0 d38696 u262144
Kernel command line: noreboot no_hash_pointers
Unknown kernel command line parameters "noreboot", will be passed to 
user space.
printk: log_buf_len individual max cpu contribution: 4096 bytes
printk: log_buf_len total cpu_extra contributions: 12288 bytes
printk: log_buf_len min size: 16384 bytes
printk: log buffer data + meta data: 32768 + 114688 = 147456 bytes
printk: early log buf free: 13552(82%)
Dentry cache hash table entries: 131072 (order: 8, 1048576 bytes, linear)
Inode-cache hash table entries: 65536 (order: 7, 524288 bytes, linear)
Built 1 zonelists, mobility grouping on.  Total pages: 262144
mem auto-init: stack:off, heap alloc:off, heap free:off
**********************************************************
**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
**                                                      **
** This system shows unhashed kernel memory addresses   **
** via the console, logs, and other interfaces. This    **
** might reduce the security of your system.            **
**                                                      **
** If you see this message and you are not debugging    **
** the kernel, report this immediately to your system   **
** administrator!                                       **
**                                                      **
** Use hash_pointers=always to force this mode off      **
**                                                      **
**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
**********************************************************
SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
rcu: Hierarchical RCU implementation.
rcu: 	RCU event tracing is enabled.
rcu: 	RCU restricting CPUs from NR_CPUS=24 to nr_cpu_ids=4.
	Tracing variant of Tasks RCU enabled.
rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4
RCU Tasks Trace: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1 
rcu_task_cpu_ids=4.
NR_IRQS: 512, nr_irqs: 512, preallocated irqs: 16
mpic: Setting up MPIC " OpenPIC  " version 1.2 at fe0040000, max 4 CPUs
mpic: ISU size: 256, shift: 8, mask: ff
mpic: Initializing for 256 sources
rcu: srcu_init: Setting srcu_struct sizes based on contention.
clocksource: timebase: mask: 0xffffffffffffffff max_cycles: 
0x5c4093a7d1, max_idle_ns: 440795210635 ns
clocksource: timebase mult[2800000] shift[24] registered
Console: colour dummy device 80x25
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 2048 (order: 2, 16384 bytes, linear)
Mountpoint-cache hash table entries: 2048 (order: 2, 16384 bytes, linear)
e500 family performance monitor hardware support registered
rcu: Hierarchical SRCU implementation.
rcu: 	Max phase no-delay instances is 1000.
Timer migration: 1 hierarchy levels; 8 children per group; 1 crossnode level
smp: Bringing up secondary CPUs ...
Activating Kernel Userspace Access Protection
Activating Kernel Userspace Access Protection
Activating Kernel Userspace Access Protection
smp: Brought up 1 node, 4 CPUs
Memory: 1001660K/1048576K available (15032K kernel code, 1540K rwdata, 
4296K rodata, 700K init, 256K bss, 41596K reserved, 0K cma-reserved)
devtmpfs: initialized
clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, 
max_idle_ns: 7645041785100000 ns
posixtimers hash table entries: 2048 (order: 3, 32768 bytes, linear)
futex hash table entries: 1024 (65536 bytes on 1 NUMA nodes, total 64 
KiB, linear).
Machine: QEMU ppce500
SoC family: QorIQ
SoC ID: svr:0x00000000, Revision: 0.0
NET: Registered PF_NETLINK/PF_ROUTE protocol family
audit: initializing netlink subsys (disabled)
audit: type=2000 audit(0.632:1): state=initialized audit_enabled=0 res=1
Found FSL PCI host bridge at 0x0000000fe0008000. Firmware bus number: 0->255
PCI host bridge /pci@fe0008000 (primary) ranges:
  MEM 0x0000000c00000000..0x0000000c1fffffff -> 0x00000000e0000000
   IO 0x0000000fe1000000..0x0000000fe100ffff -> 0x0000000000000000
/pci@fe0008000: PCICSRBAR @ 0xdff00000
setup_pci_atmu: end of DRAM 40000000
fsl-pamu: fsl_pamu_init: could not find a PAMU node
HugeTLB: registered 4.00 MiB page size, pre-allocated 0 pages
HugeTLB: 0 KiB vmemmap can be freed for a 4.00 MiB page
HugeTLB: registered 16.0 MiB page size, pre-allocated 0 pages
HugeTLB: 0 KiB vmemmap can be freed for a 16.0 MiB page
HugeTLB: registered 64.0 MiB page size, pre-allocated 0 pages
HugeTLB: 0 KiB vmemmap can be freed for a 64.0 MiB page
HugeTLB: registered 256 MiB page size, pre-allocated 0 pages
HugeTLB: 0 KiB vmemmap can be freed for a 256 MiB page
HugeTLB: registered 1.00 GiB page size, pre-allocated 0 pages
HugeTLB: 0 KiB vmemmap can be freed for a 1.00 GiB page
Freescale Elo series DMA driver
iommu: Default domain type: Translated
iommu: DMA domain TLB invalidation policy: strict mode
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
pps_core: LinuxPPS API ver. 1 registered
pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti 
<giometti@linux.it>
PTP clock support registered
Advanced Linux Sound Architecture Driver Initialized.
PCI: Probing PCI hardware
fsl-pci fe0008000.pci: PCI host bridge to bus 0000:00
pci_bus 0000:00: root bus resource [io 
0xc000180000010000-0xc00018000001ffff] (bus address [0x0000-0xffff])
pci_bus 0000:00: root bus resource [mem 0xc00000000-0xc1fffffff] (bus 
address [0xe0000000-0xffffffff])
pci_bus 0000:00: root bus resource [bus 00-ff]
pci_bus 0000:00: busn_res: [bus 00-ff] end is updated to ff
pci 0000:00:00.0: [1957:0030] type 00 class 0x0b2000 conventional PCI 
endpoint
pci 0000:00:00.0: BAR 0 [mem 0xdff00000-0xdfffffff]
pci 0000:00:01.0: [8086:100e] type 00 class 0x020000 conventional PCI 
endpoint
pci 0000:00:01.0: BAR 0 [mem 0x00000000-0x0001ffff]
pci 0000:00:01.0: BAR 1 [io  0xc000180000010000-0xc00018000001003f]
pci 0000:00:01.0: ROM [mem 0x00000000-0x0003ffff pref]
pci_bus 0000:00: busn_res: [bus 00-ff] end is updated to 00
pci 0000:00:01.0: ROM [mem 0xc00000000-0xc0003ffff pref]: assigned
pci 0000:00:01.0: BAR 0 [mem 0xc00040000-0xc0005ffff]: assigned
pci 0000:00:01.0: BAR 1 [io  0xc000180000010000-0xc00018000001003f]: 
assigned
pci_bus 0000:00: resource 4 [io  0xc000180000010000-0xc00018000001ffff]
pci_bus 0000:00: resource 5 [mem 0xc00000000-0xc1fffffff]
vgaarb: loaded
clocksource: Switched to clocksource timebase
NET: Registered PF_INET protocol family
IP idents hash table entries: 16384 (order: 5, 131072 bytes, linear)
tcp_listen_portaddr_hash hash table entries: 512 (order: 1, 8192 bytes, 
linear)
Table-perturb hash table entries: 65536 (order: 6, 262144 bytes, linear)
TCP established hash table entries: 8192 (order: 4, 65536 bytes, linear)
TCP bind hash table entries: 8192 (order: 6, 262144 bytes, linear)
TCP: Hash tables configured (established 8192 bind 8192)
UDP hash table entries: 512 (order: 3, 32768 bytes, linear)
UDP-Lite hash table entries: 512 (order: 3, 32768 bytes, linear)
NET: Registered PF_UNIX/PF_LOCAL protocol family
RPC: Registered named UNIX socket transport module.
RPC: Registered udp transport module.
RPC: Registered tcp transport module.
RPC: Registered tcp-with-tls transport module.
RPC: Registered tcp NFSv4.1 backchannel transport module.
PCI: CLS 0 bytes, default 64
workingset: timestamp_bits=62 max_order=18 bucket_order=0
Trying to unpack rootfs image as initramfs...
NFS: Registering the id_resolver key type
Key type id_resolver registered
Key type id_legacy registered
jffs2: version 2.2. (NAND) © 2001-2006 Red Hat, Inc.
io scheduler mq-deadline registered
io scheduler kyber registered
io scheduler bfq registered
Serial: 8250/16550 driver, 6 ports, IRQ sharing enabled
printk: legacy console [ttyS0] disabled
serial8250.0: ttyS0 at MMIO 0xfe0004500 (irq = 42, base_baud = 25000000) 
is a 16550A
printk: legacy console [ttyS0] enabled
printk: legacy console [ttyS0] enabled
printk: legacy bootconsole [udbg0] disabled
printk: legacy bootconsole [udbg0] disabled
ePAPR hypervisor byte channel driver
brd: module loaded
Freeing initrd memory: 1860K
loop: module loaded
st: Version 20160209, fixed bufsize 32768, s/g segs 256
e1000: Intel(R) PRO/1000 Network Driver
e1000: Copyright (c) 1999-2006 Intel Corporation.
e1000 0000:00:01.0: enabling device (0000 -> 0003)
e1000 0000:00:01.0 eth0: (PCI:33MHz:32-bit) 52:54:00:12:34:56
e1000 0000:00:01.0 eth0: Intel(R) PRO/1000 Network Connection
e1000e: Intel(R) PRO/1000 Network Driver
e1000e: Copyright(c) 1999 - 2015 Intel Corporation.
igb: Intel(R) Gigabit Ethernet Network Driver
igb: Copyright (c) 2007-2014 Intel Corporation.
usbcore: registered new interface driver usb-storage
i2c_dev: i2c /dev entries driver
mpc-i2c fe0003000.i2c: timeout 1000000 us
rtc-ds1307 0-0068: registered as rtc0
rtc-ds1307 0-0068: setting system clock to 2025-12-08T09:49:59 UTC 
(1765187399)
sdhci: Secure Digital Host Controller Interface driver
sdhci: Copyright(c) Pierre Ossman
sdhci-pltfm: SDHCI platform and OF driver helper
Freescale hypervisor management driver
fsl-hv: no hypervisor found
ipip: IPv4 and MPLS over IPv4 tunneling driver
mmc0 bounce up to 128 segments into one, max segment size 65536 bytes
Initializing XFRM netlink socket
NET: Registered PF_INET6 protocol family
mmc0: SDHCI controller on fe002e000.sdhc [fe002e000.sdhc] using DMA
Segment Routing with IPv6
In-situ OAM (IOAM) with IPv6
sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver
NET: Registered PF_PACKET protocol family
PFKEY is deprecated and scheduled to be removed in 2027, please contact 
the netdev mailing list
NET: Registered PF_KEY protocol family
Key type dns_resolver registered
clk: Disabling unused clocks
ALSA device list:
   No soundcards found.
Freeing unused kernel image (initmem) memory: 700K
This architecture does not have kernel memory protection.
Run /init as init process
mount: mounting devtmpfs on /dev failed: Device or resource busy
Starting logging: OK
Initializing random number generator... done.
Starting network: OK
Found console ttyS0

Boot successful.
/ # ls -l
total 8
drwxr-xr-x    2 root     root          1500 Jul 12  2018 bin
drwxr-xr-x    5 root     root          2880 Dec  8 09:50 dev
drwxr-xr-x    5 root     root           440 Dec  8 09:50 etc
-rwxr-xr-x    1 root     root           178 Jul 12  2018 init
drwxr-xr-x    2 root     root           660 Jul 12  2018 lib
lrwxrwxrwx    1 root     root             3 Jul 12  2018 lib32 -> lib
lrwxrwxrwx    1 root     root            11 Jul 12  2018 linuxrc -> 
bin/busybox
drwxr-xr-x    2 root     root            40 Feb 20  2018 media
drwxr-xr-x    2 root     root            40 Feb 20  2018 mnt
drwxr-xr-x    2 root     root            40 Feb 20  2018 opt
dr-xr-xr-x  150 root     root             0 Dec  8 09:50 proc
drwx------    2 root     root            40 Feb 24  2018 root
drwxr-xr-x    3 root     root           140 Dec  8 09:50 run
-rwxr-xr-x    1 root     root           238 Jul 12  2018 run.sh
drwxr-xr-x    2 root     root          1100 Jul 12  2018 sbin
dr-xr-xr-x   11 root     root             0 Dec  8 09:50 sys
drwxrwxrwt    2 root     root            60 Dec  8 09:50 tmp
drwxr-xr-x    6 root     root           140 Jul 12  2018 usr
drwxr-xr-x    4 root     root           200 Jul 12  2018 var
/ #

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

On 08 December 2025 at 10:54 am, Christophe Leroy (CS GROUP) <chleroy@kernel.org> wrote:

Hello,

Can you provide more details on your problem, the full messages before the Oops, and your .config ?

Thanks
Christophe

- - -

Hello Christophe,

Here is the kernel config:

https://raw.githubusercontent.com/chzigotzky/kernels/refs/heads/main/configs/e5500_defconfig

[PPC] [e5500] Boot issues after the PowerPC updates 6.19-1 #18: https://github.com/chzigotzky/kernels/issues/18

git revert ad952db4a865e96ec98d4c5874a4699fe3286d56 -m 

After a compiling the kernel boots again.

Thanks,
Christian

[PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

On 08/12/25 13:06, Christian Zigotzky wrote:
> On 08 December 2025 at 10:54 am, Christophe Leroy (CS GROUP) <chleroy@kernel.org> wrote:
>
> Hello,
>
> Can you provide more details on your problem, the full messages before the Oops, and your .config ?
>
> Thanks
> Christophe
>
> - - -
>
> Hello Christophe,
>
> Here is the kernel config:
>
> https://raw.githubusercontent.com/chzigotzky/kernels/refs/heads/main/configs/e5500_defconfig
>
> [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1 #18: https://github.com/chzigotzky/kernels/issues/18
>
> git revert ad952db4a865e96ec98d4c5874a4699fe3286d56 -m
>
> After a compiling the kernel boots again.
>
> Thanks,
> Christian

Serial log with kernel error messages: 
https://github.com/user-attachments/files/24035394/Kernel_6.19.0_Cyrus_Plus_board_P5040.log

After a revert of the powerpc updates 6.19-1, the kernel boots without 
any problems on our e5500 machines.

-- 
Sent with BrassMonkey 33.9.1 (https://github.com/chzigotzky/Web-Browsers-and-Suites-for-Linux-PPC/releases/tag/BrassMonkey_33.9.1)

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Gautam Menghani]

On Mon, Dec 08, 2025 at 07:06:14AM +0100, Christian Zigotzky wrote:
> 
> > On 08 December 2025 at 06:51 am, Gautam Menghani <gautam@linux.ibm.com> wrote:
> > 
> > Hi Christian,
> > 
> > Thanks for the report. Can you also please share the QEMU command line
> > you were using? That would be helpful.
> > 
> > Thanks,
> > Gautam
> 
> Hi Gautam,
> 
> Here is the command line:
> 
> qemu-system-ppc64 -M ppce500 -cpu e5500 -m 1024 -kernel uImage -drive format=raw,file=void-live-powerpc-20230317.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-gpu-pci -device virtio-mouse-pci -device virtio-keyboard-pci -device pci-ohci,id=newusb -audiodev id=sndbe,driver=pa,server=/run/user/1000/pulse/native -device usb-audio,bus=newusb.0 -enable-kvm -smp 4 -fsdev local,security_model=passthrough,id=fsdev0,path=/home/amigaone/Music -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=hostshare -display gtk


Were you running a KVM guest? Did you see the problem with the latest
kernel installed in the guest?

> 
> Thanks,
> Christian

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

> On 09 December 2025 at 07:01 am, Gautam Menghani <gautam@linux.ibm.com> wrote:
> 
> On Mon, Dec 08, 2025 at 07:06:14AM +0100, Christian Zigotzky wrote:
>> 
>>>> On 08 December 2025 at 06:51 am, Gautam Menghani <gautam@linux.ibm.com> wrote:
>>> 
>>> Hi Christian,
>>> 
>>> Thanks for the report. Can you also please share the QEMU command line
>>> you were using? That would be helpful.
>>> 
>>> Thanks,
>>> Gautam
>> 
>> Hi Gautam,
>> 
>> Here is the command line:
>> 
>> qemu-system-ppc64 -M ppce500 -cpu e5500 -m 1024 -kernel uImage -drive format=raw,file=void-live-powerpc-20230317.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-gpu-pci -device virtio-mouse-pci -device virtio-keyboard-pci -device pci-ohci,id=newusb -audiodev id=sndbe,driver=pa,server=/run/user/1000/pulse/native -device usb-audio,bus=newusb.0 -enable-kvm -smp 4 -fsdev local,security_model=passthrough,id=fsdev0,path=/home/amigaone/Music -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=hostshare -display gtk
> 
> 
> Were you running a KVM guest? Did you see the problem with the latest
> kernel installed in the guest?

Yes, the latest git kernel doesn’t boot.

But the final kernel 6.18.0 boots without any problems.

Thank you for your help.

- Christian

[PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

I bisected today.

1. git clone https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git -b powerpc-6.19-1 a

2. cd a

3. git log

Output:

commit 9b36c7fc5aa5f2c6e6eeb9f312fdfe61b4291c9f (HEAD, tag: powerpc-6.19-1, origin/next-test, origin/next)

...

4. git bisect start

5. git bisect good f850568efe3a7a9ec4df357cfad1f997f0058924

Merge tag 'i2c-for-6.18-rc5'

6. git bisect bad 9b36c7fc5aa5f2c6e6eeb9f312fdfe61b4291c9f

macintosh/via-pmu-backlight: Include <linux/fb.h> and <linux/of.h>

7. git bisect bad

8. git bisect bad

9. git bisect good

10. git bisect bad

11. git bisect good

2997876c4a1a5864baa13d7393c2b68cf5b51183 is the first bad commit
commit 2997876c4a1a5864baa13d7393c2b68cf5b51183
Author: Christophe Leroy <christophe.leroy@csgroup.eu>
Date:   Thu Sep 11 14:30:12 2025 +0200

    powerpc/32: Restore clearing of MSR[RI] at interrupt/syscall exit

    Commit 13799748b957 ("powerpc/64: use interrupt restart table to speed
    up return from interrupt") removed the inconditional clearing of
    MSR[RI] when returning from interrupt into kernel. But powerpc/32
    doesn't implement interrupt restart table hence still need MSR[RI]
    to be cleared.

    It could be added back in interrupt_exit_kernel_prepare() but it is
    easier and better to add it back in entry_32.S for following reasons:
    - Writing to MSR must be followed by a synchronising instruction
    - The smaller the non recoverable section is the better it is

    So add a macro called clr_ri and use it in the three places that play
    up with SRR0/SRR1. Use it just before another mtspr for synchronisation
    to avoid having to add an isync.

    Now that's done in entry_32.S, exit_must_hard_disable() can return
    false for non book3s/64, taking into account that BOOKE doesn't have
    MSR_RI.

    Also add back blacklisting syscall_exit_finish for kprobe. This was
    initially added by commit 7cdf44013885 ("powerpc/entry32: Blacklist
    syscall exit points for kprobe.") then lost with
    commit 6f76a01173cc ("powerpc/syscall: implement system call
    entry/exit logic in C for PPC32").

    Fixes: 6f76a01173cc ("powerpc/syscall: implement system call entry/exit logic in C for PPC32")
    Fixes: 13799748b957 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
    Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
    Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
    Link: https://patch.msgid.link/66d0ab070563ad460ed481328ab0887c27f21a2c.1757593807.git.christophe.leroy@csgroup.eu

 arch/powerpc/kernel/entry_32.S  | 18 +++++++++++++++++-
 arch/powerpc/kernel/interrupt.c |  2 +-
 2 files changed, 18 insertions(+), 2 deletions(-)

12. git revert 2997876c4a1a5864baa13d7393c2b68cf5b51183

After reverting the first bad commit, the kernel boots without any problems.

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

> On 09 December 2025 at 10:03 am, Christian Zigotzky <chzigotzky@xenosoft.de> wrote:
> 
> I bisected today.
> 
> 1. git clone https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git -b powerpc-6.19-1 a
> 
> 2. cd a
> 
> 3. git log
> 
> Output:
> 
> commit 9b36c7fc5aa5f2c6e6eeb9f312fdfe61b4291c9f (HEAD, tag: powerpc-6.19-1, origin/next-test, origin/next)
> 
> ...
> 
> 4. git bisect start
> 
> 5. git bisect good f850568efe3a7a9ec4df357cfad1f997f0058924
> 
> Merge tag 'i2c-for-6.18-rc5'
> 
> 6. git bisect bad 9b36c7fc5aa5f2c6e6eeb9f312fdfe61b4291c9f
> 
> macintosh/via-pmu-backlight: Include <linux/fb.h> and <linux/of.h>
> 
> 7. git bisect bad
> 
> 8. git bisect bad
> 
> 9. git bisect good
> 
> 10. git bisect bad
> 
> 11. git bisect good
> 
> 2997876c4a1a5864baa13d7393c2b68cf5b51183 is the first bad commit
> commit 2997876c4a1a5864baa13d7393c2b68cf5b51183
> Author: Christophe Leroy <christophe.leroy@csgroup.eu>
> Date:   Thu Sep 11 14:30:12 2025 +0200
> 
>    powerpc/32: Restore clearing of MSR[RI] at interrupt/syscall exit
> 
>    Commit 13799748b957 ("powerpc/64: use interrupt restart table to speed
>    up return from interrupt") removed the inconditional clearing of
>    MSR[RI] when returning from interrupt into kernel. But powerpc/32
>    doesn't implement interrupt restart table hence still need MSR[RI]
>    to be cleared.
> 
>    It could be added back in interrupt_exit_kernel_prepare() but it is
>    easier and better to add it back in entry_32.S for following reasons:
>    - Writing to MSR must be followed by a synchronising instruction
>    - The smaller the non recoverable section is the better it is
> 
>    So add a macro called clr_ri and use it in the three places that play
>    up with SRR0/SRR1. Use it just before another mtspr for synchronisation
>    to avoid having to add an isync.
> 
>    Now that's done in entry_32.S, exit_must_hard_disable() can return
>    false for non book3s/64, taking into account that BOOKE doesn't have
>    MSR_RI.
> 
>    Also add back blacklisting syscall_exit_finish for kprobe. This was
>    initially added by commit 7cdf44013885 ("powerpc/entry32: Blacklist
>    syscall exit points for kprobe.") then lost with
>    commit 6f76a01173cc ("powerpc/syscall: implement system call
>    entry/exit logic in C for PPC32").
> 
>    Fixes: 6f76a01173cc ("powerpc/syscall: implement system call entry/exit logic in C for PPC32")
>    Fixes: 13799748b957 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
>    Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
>    Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
>    Link: https://patch.msgid.link/66d0ab070563ad460ed481328ab0887c27f21a2c.1757593807.git.christophe.leroy@csgroup.eu
> 
> arch/powerpc/kernel/entry_32.S  | 18 +++++++++++++++++-
> arch/powerpc/kernel/interrupt.c |  2 +-
> 2 files changed, 18 insertions(+), 2 deletions(-)
> 
> 12. git revert 2997876c4a1a5864baa13d7393c2b68cf5b51183
> 
> After reverting the first bad commit, the kernel boots without any problems.
> 

I created a patch for reverting the first bad commit.

After patching, the kernel boots without any problems.

diff -rupN a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
--- a/arch/powerpc/kernel/entry_32.S	2025-12-09 06:57:20.681347393 +0100
+++ b/arch/powerpc/kernel/entry_32.S	2025-12-09 10:24:37.357301725 +0100
@@ -101,17 +101,6 @@ SYM_FUNC_END(__kuep_unlock)
 .endm
 #endif
 
-.macro	clr_ri trash
-#ifndef CONFIG_BOOKE
-#ifdef CONFIG_PPC_8xx
-	mtspr   SPRN_NRI, \trash
-#else
-	li	\trash, MSR_KERNEL & ~MSR_RI
-	mtmsr	\trash
-#endif
-#endif
-.endm
-
 	.globl	transfer_to_syscall
 transfer_to_syscall:
 	stw	r3, ORIG_GPR3(r1)
@@ -160,7 +149,6 @@ ret_from_syscall:
 	cmpwi	r3,0
 	REST_GPR(3, r1)
 syscall_exit_finish:
-	clr_ri	r4
 	mtspr	SPRN_SRR0,r7
 	mtspr	SPRN_SRR1,r8
 
@@ -180,7 +168,6 @@ syscall_exit_finish:
 	REST_GPR(0, r1)
 	REST_GPRS(3, 12, r1)
 	b	1b
-_ASM_NOKPROBE_SYMBOL(syscall_exit_finish)
 
 #ifdef CONFIG_44x
 .L44x_icache_flush:
@@ -237,11 +224,10 @@ fast_exception_return:
 	/* Clear the exception marker on the stack to avoid confusing stacktrace */
 	li	r10, 0
 	stw	r10, 8(r11)
-	clr_ri	r10
+	REST_GPR(10, r11)
 	mtspr	SPRN_SRR1,r9
 	mtspr	SPRN_SRR0,r12
 	REST_GPR(9, r11)
-	REST_GPR(10, r11)
 	REST_GPR(12, r11)
 	REST_GPR(11, r11)
 	rfi
@@ -270,7 +256,6 @@ interrupt_return:
 .Lfast_user_interrupt_return:
 	lwz	r11,_NIP(r1)
 	lwz	r12,_MSR(r1)
-	clr_ri	r4
 	mtspr	SPRN_SRR0,r11
 	mtspr	SPRN_SRR1,r12
 
@@ -313,7 +298,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRE
 	cmpwi	cr1,r3,0
 	lwz	r11,_NIP(r1)
 	lwz	r12,_MSR(r1)
-	clr_ri	r4
 	mtspr	SPRN_SRR0,r11
 	mtspr	SPRN_SRR1,r12
 
diff -rupN a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
--- a/arch/powerpc/kernel/interrupt.c	2025-12-09 06:57:20.717347165 +0100
+++ b/arch/powerpc/kernel/interrupt.c	2025-12-09 10:24:37.357301725 +0100
@@ -38,7 +38,7 @@ static inline bool exit_must_hard_disabl
 #else
 static inline bool exit_must_hard_disable(void)
 {
-	return false;
+	return true;
 }
 #endif

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

Hello Christophe,

The following commit is responsible for the boot issue.

2997876c4a1a5864baa13d7393c2b68cf5b51183 powerpc/32: Restore clearing of MSR[RI] at interrupt/syscall exit

I don't think the commit is faulty.

Could you please check my kernel config and the serial log?

- https://github.com/chzigotzky/kernels/blob/main/configs/e5500_defconfig

- https://github.com/user-attachments/files/24035394/Kernel_6.19.0_Cyrus_Plus_board_P5040.log

Maybe, the kernel config isn’t correct for the kernel 6.19.

Thanks in advance,
Christian

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Gautam Menghani]

On Tue, Dec 09, 2025 at 09:34:11AM +0100, Christian Zigotzky wrote:
> 
> 
> > On 09 December 2025 at 07:01 am, Gautam Menghani <gautam@linux.ibm.com> wrote:
> > 
> > On Mon, Dec 08, 2025 at 07:06:14AM +0100, Christian Zigotzky wrote:
> >> 
> >>>> On 08 December 2025 at 06:51 am, Gautam Menghani <gautam@linux.ibm.com> wrote:
> >>> 
> >>> Hi Christian,
> >>> 
> >>> Thanks for the report. Can you also please share the QEMU command line
> >>> you were using? That would be helpful.
> >>> 
> >>> Thanks,
> >>> Gautam
> >> 
> >> Hi Gautam,
> >> 
> >> Here is the command line:
> >> 
> >> qemu-system-ppc64 -M ppce500 -cpu e5500 -m 1024 -kernel uImage -drive format=raw,file=void-live-powerpc-20230317.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-gpu-pci -device virtio-mouse-pci -device virtio-keyboard-pci -device pci-ohci,id=newusb -audiodev id=sndbe,driver=pa,server=/run/user/1000/pulse/native -device usb-audio,bus=newusb.0 -enable-kvm -smp 4 -fsdev local,security_model=passthrough,id=fsdev0,path=/home/amigaone/Music -device virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=hostshare -display gtk
> > 
> > 
> > Were you running a KVM guest? Did you see the problem with the latest
> > kernel installed in the guest?
> 
> Yes, the latest git kernel doesn’t boot.
> 
> But the final kernel 6.18.0 boots without any problems.

I tried booting a TCG ppce500 guest with your config and I can see that
the commit 2997876c4a1a5 causes a boot failure. Reverting it works fine.

Command line used:

qemu-system-ppc64 -M ppce500 -cpu e5500 -smp 1 -m 4G \
    -display none -serial stdio \
    -kernel /home/gautam/src/linux/arch/powerpc/boot/uImage \
    -drive file=/home/gautam/src/qemu-ppc-boot/buildroot/qemu_ppc64_e5500-latest/rootfs.ext2,if=virtio,format=raw \
    -append "console=ttyS0 rootwait root=/dev/vda" \


But I was not able to boot a KVM guest on top of this TCG guest. I even
went back all the way to 5.15

./qemu-system-ppc64 \
        -M ppce500 -cpu e5500 \
        --enable-kvm  \
        -m 1024 -kernel uImage \
        -drive file=/tmp/rootfs.ext2,if=virtio,format=raw \
        -append "console=ttyS0 rootwait root=/dev/vda" -serial mon:stdio -nographic

Bad kernel stack pointer fffff8 at 0
Oops: Bad kernel stack pointer, sig: 6 [#1]
BE PAGE_SIZE=4K  SMP NR_CPUS=4 QEMU e500
Modules linked in:
CPU: 0 UID: 0 PID: 1508 Comm: qemu-system-ppc Not tainted 6.18.0-a4-powerpc64-smp #45 VOLUNTARY
Hardware name: QEMU ppce500 e5500 0x80240020 QEMU e500
NIP:  0000000000000000 LR: 0000000000000000 CTR: 0000000000000000
REGS: c00000003fffbd20 TRAP: 0400   Not tainted  (6.18.0-a4-powerpc64-smp)
MSR:  0000000010000000 <>  CR: 00000000  XER: 00000000
IRQMASK: 0
GPR00: 0000000000000000 0000000000fffff8 0000000000000000 0000000002c00000
GPR04: 0000000000000000 0000000000000000 0000000045504150 0000000004000000
GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR12: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR28: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
NIP [0000000000000000] 0x0
LR [0000000000000000] 0x0
Call Trace:
Code: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
---[ end trace 0000000000000000 ]---

note: qemu-system-ppc[1508] exited with irqs disabled


Thanks,
Gautam

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

Hello Christophe,

I was able to reduce the patch.

The following modification is responsible for the boot issue:

diff -rupN a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
--- a/arch/powerpc/kernel/interrupt.c	2025-12-09 06:57:20.717347165 +0100
+++ b/arch/powerpc/kernel/interrupt.c	2025-12-09 10:24:37.357301725 +0100
@@ -38,7 +38,7 @@ static inline bool exit_must_hard_disabl
 #else
 static inline bool exit_must_hard_disable(void)
 {
-	return false;
+	return true;
 }
 #endif

- - -

After reverting this modification, the kernel boots without any problems.

Please check this modification.

Thanks,
Christian

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christian Zigotzky]

> On 11 December 2025 at 07:27 am, Christian Zigotzky <chzigotzky@xenosoft.de> wrote:
> 
> Hello Christophe,
> 
> I was able to reduce the patch.
> 
> The following modification is responsible for the boot issue:

Christophe,

This is the new reverting patch:

> 
> diff -rupN a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
> --- a/arch/powerpc/kernel/interrupt.c    2025-12-09 06:57:20.717347165 +0100
> +++ b/arch/powerpc/kernel/interrupt.c    2025-12-09 10:24:37.357301725 +0100
> @@ -38,7 +38,7 @@ static inline bool exit_must_hard_disabl
> #else
> static inline bool exit_must_hard_disable(void)
> {
> -    return false;
> +    return true;
> }
> #endif
> 
> - - -
> 
> After reverting this modification, the kernel boots without any problems.

After reverting the modification with this patch, the kernel boots without any problems.

> 
> Please check this modification.
> 
> Thanks,
> Christian

Re: [PPC] [e5500] Boot issues after the PowerPC updates 6.19-1

[Christophe Leroy (CS GROUP)]

Hi Christian,

Le 11/12/2025 à 07:26, Christian Zigotzky a écrit :
> Hello Christophe,
> 
> I was able to reduce the patch.
> 
> The following modification is responsible for the boot issue:
> 
> diff -rupN a/arch/powerpc/kernel/interrupt.c b/arch/powerpc/kernel/interrupt.c
> --- a/arch/powerpc/kernel/interrupt.c	2025-12-09 06:57:20.717347165 +0100
> +++ b/arch/powerpc/kernel/interrupt.c	2025-12-09 10:24:37.357301725 +0100
> @@ -38,7 +38,7 @@ static inline bool exit_must_hard_disabl
>   #else
>   static inline bool exit_must_hard_disable(void)
>   {
> -	return false;
> +	return true;
>   }
>   #endif
> 
> - - -
> 
> After reverting this modification, the kernel boots without any problems.
> 
> Please check this modification.

Yes indeed, I realised that allthough the BOOKE powerpc doesn't have the 
RI bit, this call is still necessary to switch off IRQs in case they are 
still on.

So I have to think a bit deeper and see what the solution could be. I 
will let you know as soon as I have a solution.

Christophe