On Wed, 2021-04-28 at 08:08 +0200, Christophe Leroy wrote: > > Le 28/04/2021 à 00:42, Eddie James a écrit : > > On Tue, 2021-04-27 at 19:26 +0200, Christophe Leroy wrote: > > > Hi Eddies, > > > > > > Le 27/04/2021 à 19:03, Eddie James a écrit : > > > > Hi all, > > > > > > > > I'm having a problem in simulation and hardware where my PPC476 > > > > processor stops executing instructions after callling /init. In > > > > my > > > > case > > > > this is a bash script. The code descends to flush the TLB, and > > > > somewhere in the loop in _tlbil_pid, the PC goes to > > > > InstructionTLBError47x but does not go any further. This only > > > > occurs in > > > > the crash kernel environment, which is using the same kernel, > > > > initramfs, and init script as the main kernel, which executed > > > > fine. > > > > I > > > > do not see this problem with linux 4.19 or 3.10. I do see it > > > > with > > > > 5.4 > > > > and 5.10. I see a fair amount of refactoring in the PPC memory > > > > management area between 4.19 and 5.4. Can anyone point me in a > > > > direction to debug this further? My stack trace is below as I > > > > can > > > > run > > > > gdb in simulation. > > > > > > Can you bisect to pin point the culprit commit ? > > > > Hi, thanks for your prompt reply. > > > > Good idea! I have bisected to: > > > > commit 9e849f231c3c72d4c3c1b07c9cd19ae789da0420 (b8-bad, > > refs/bisect/bad) > > Author: Christophe Leroy <christophe.le...@c-s.fr> > > Date: Thu Feb 21 19:08:40 2019 +0000 > > > > powerpc/mm/32s: use generic mmu_mapin_ram() for all blocks. > > > > Now that mmu_mapin_ram() is able to handle other blocks > > than the one starting at 0, the WII can use it for all > > its blocks. > > > > Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> > > Signed-off-by: Michael Ellerman <m...@ellerman.id.au> > > > > I also confirmed that reverting this commit resolves the issue in > > 5.4+. > > > > Now, I don't understand why this is problematic or what is really > > happening... Reverting is probably not the desired solution. > > > > Can you provide the 'dmesg' or a dump of the logs printed by the > kernel at boottime ?
Yes: [ 0.000000] Linux version 5.4.85-a19ab63.ppcnf-fsp2 (oe-user@oe-host ) (gcc ve rsion 8.3.0 (GCC)) #1 Tue Mar 30 15:32:31 UTC 2021 [ 0.000000] Found initrd at 0xcf6a7000:0xcfffb09f [ 0.000000] Using FSP-2 machine description [ 0.000000] Found legacy serial port 0 for /plb4/opb/serial@b0020000 [ 0.000000] mem=10b0020000, taddr=10b0020000, irq=0, clk=20833333, speed=11 5200 [ 0.000000] ----------------------------------------------------- [ 0.000000] phys_mem_size = 0x4000000 [ 0.000000] dcache_bsize = 0x80 [ 0.000000] icache_bsize = 0x20 [ 0.000000] cpu_features = 0x0000000040800120 [ 0.000000] possible = 0x0000000040800120 [ 0.000000] always = 0x0000000000000020 [ 0.000000] cpu_user_features = 0x8c008000 0x00000000 [ 0.000000] mmu_features = 0x00140020 [ 0.000000] physical_start = 0xc000000 [ 0.000000] ----------------------------------------------------- [ 0.000000] Top of RAM: 0x10000000, Total RAM: 0x4000000 [ 0.000000] Memory hole size: 192MB [ 0.000000] Zone ranges: [ 0.000000] Normal [mem 0x000000000c000000-0x000000000fffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x000000000c000000-0x000000000fffffff] [ 0.000000] Initmem setup node 0 [mem 0x000000000c000000- 0x000000000fffffff] [ 0.000000] On node 0 totalpages: 16384 [ 0.000000] Normal zone: 160 pages used for memmap [ 0.000000] Normal zone: 0 pages reserved [ 0.000000] Normal zone: 16384 pages, LIFO batch:3 [ 0.000000] MMU: Allocated 278528 bytes of context maps for 65535 contexts [ 0.000000] pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768 [ 0.000000] pcpu-alloc: [0] 0 [ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 16224 [ 0.000000] Kernel command line: console=ttyS0,115200 loglevel=9 rootwait roo t=/dev/mmcblk0p2 elfcorehdr=209456K maxcpus=1 [ 0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes, lin ear) [ 0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes, line ar) [ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off [ 0.000000] Memory: 42028K/65536K available (7136K kernel code, 620K rwdata, 1916K rodata, 2080K init, 233K bss, 23508K reserved, 0K cma-reserved) [ 0.000000] Kernel virtual memory layout: [ 0.000000] * 0xfffdf000..0xfffff000 : fixmap [ 0.000000] * 0xd1000000..0xfffdf000 : vmalloc & ioremap [ 0.000000] SLUB: HWalign=128, Order=0-3, MinObjects=0, CPUs=1, Nodes=1 [ 0.000000] NR_IRQS: 512, nr_irqs: 512, preallocated irqs: 16 [ 0.000000] UIC0 (32 IRQ sources) at DCR 0x2c0 [ 0.000000] UIC1 (32 IRQ sources) at DCR 0x2c8 [ 0.000000] UIC2 (32 IRQ sources) at DCR 0x350 [ 0.000000] UIC3 (32 IRQ sources) at DCR 0x358 [ 0.000000] UIC4 (32 IRQ sources) at DCR 0x360 [ 0.000000] UIC5 (32 IRQ sources) at DCR 0x368 [ 0.000000] UIC6 (32 IRQ sources) at DCR 0x370 [ 0.000000] UIC7 (32 IRQ sources) at DCR 0x2d0 [ 0.000000] UIC8 (32 IRQ sources) at DCR 0x2d8 [ 0.000000] UIC17 (32 IRQ sources) at DCR 0x320 [ 0.000000] UIC18 (32 IRQ sources) at DCR 0x328 [ 0.000000] UIC19 (32 IRQ sources) at DCR 0x330 [ 0.000000] UIC20 (32 IRQ sources) at DCR 0x338 [ 0.000000] UIC21 (32 IRQ sources) at DCR 0x340 [ 0.000000] UIC22 (32 IRQ sources) at DCR 0x348 [ 0.000000] UIC9 (32 IRQ sources) at DCR 0x2e0 [ 0.000000] UIC10 (32 IRQ sources) at DCR 0x2e8 [ 0.000000] UIC11 (32 IRQ sources) at DCR 0x2f0 [ 0.000000] UIC12 (32 IRQ sources) at DCR 0x2f8 [ 0.000000] UIC13 (32 IRQ sources) at DCR 0x300 [ 0.000000] UIC14 (32 IRQ sources) at DCR 0x308 [ 0.000000] UIC15 (32 IRQ sources) at DCR 0x310 [ 0.000000] UIC16 (32 IRQ sources) at DCR 0x318 [ 0.000000] random: get_random_u32 called from start_kernel+0x32c/0x500 with crng_init=0 [ 0.000000] time_init: decrementer frequency = 166.666667 MHz [ 0.000000] time_init: processor frequency = 1333.333333 MHz [ 0.000004] clocksource: timebase: mask: 0xffffffffffffffff max_cycles: 0x267 03d839d, max_idle_ns: 440795207088 ns [ 0.000007] clocksource: timebase mult[6000000] shift[24] registered [ 0.000011] clockevent: decrementer mult[2aaaaaac] shift[32] cpu[0] [ 0.000071] pid_max: default: 32768 minimum: 301 [ 0.000107] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes, linea r) [ 0.000111] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes, linear) [ 0.000580] devtmpfs: initialized [ 0.002029] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, ma x_idle_ns: 7645041785100000 ns [ 0.002034] futex hash table entries: 256 (order: -1, 3072 bytes, linear) [ 0.002146] NET: Registered protocol family 16 [ 0.004958] SCSI subsystem initialized [ 0.004973] libata version 3.00 loaded. [ 0.005003] usbcore: registered new interface driver usbfs [ 0.005019] usbcore: registered new interface driver hub [ 0.005031] usbcore: registered new device driver usb [ 0.005043] pps_core: LinuxPPS API ver. 1 registered [ 0.005045] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giome tti <giome...@linux.it> [ 0.005052] PTP clock support registered [ 0.005257] clocksource: Switched to clocksource timebase [ 0.311619] thermal_sys: Registered thermal governor 'step_wise' [ 0.311665] NET: Registered protocol family 2 [ 0.311834] tcp_listen_portaddr_hash hash table entries: 512 (order: 0, 4096 bytes, linear) [ 0.311844] TCP established hash table entries: 1024 (order: 0, 4096 bytes, l inear) [ 0.311855] TCP bind hash table entries: 1024 (order: 0, 4096 bytes, linear) [ 0.311864] TCP: Hash tables configured (established 1024 bind 1024) [ 0.311877] UDP hash table entries: 256 (order: 0, 4096 bytes, linear) [ 0.311885] UDP-Lite hash table entries: 256 (order: 0, 4096 bytes, linear) [ 0.311918] NET: Registered protocol family 1 [ 0.311994] RPC: Registered named UNIX socket transport module. [ 0.311996] RPC: Registered udp transport module. [ 0.311999] RPC: Registered tcp transport module. [ 0.312001] RPC: Registered tcp NFSv4.1 backchannel transport module. [ 0.312043] Trying to unpack rootfs image as initramfs... [ 0.632637] Freeing initrd memory: 9552K [ 0.634361] shadow_disr_to_uic15: 0x00000020 to uic15_pr [ 0.635621] workingset: timestamp_bits=30 max_order=14 bucket_order=0 [ 0.638710] NFS: Registering the id_resolver key type [ 0.638717] Key type id_resolver registered [ 0.638720] Key type id_legacy registered [ 0.638730] jffs2: version 2.2. (NAND) (SUMMARY) © 2001-2006 Red Hat, Inc. [ 0.638858] fuse: init (API version 7.31) [ 0.664372] io scheduler mq-deadline registered [ 0.664375] io scheduler kyber registered [ 0.664573] Serial: 8250/16550 driver, 32 ports, IRQ sharing enabled [ 0.665728] printk: console [ttyS0] disabled [ 0.685664] serial8250.0: ttyS0 at MMIO 0x10b0020000 (irq = 47, base_baud = 1 302083) is a 16550A [ 0.693859] printk: console [ttyS0] enabled [ 0.694150] printk: console [ttyS0] disabled [ 0.694212] 10b0020000.serial: ttyS0 at MMIO 0x10b0020000 (irq = 47, base_bau d = 1302083) is a 16550 [ 0.702632] printk: console [ttyS0] enabled [ 0.704642] brd: module loaded [ 0.704730] slram: not enough parameters. [ 0.704792] PPP generic driver version 2.4.2 [ 0.704875] PPP Deflate Compression module registered [ 0.704941] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver [ 0.705052] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver [ 0.705148] usbcore: registered new interface driver usb-storage [ 0.705248] usbcore: registered new interface driver usbserial_generic [ 0.705341] usbserial: USB Serial support registered for generic [ 0.705428] usbcore: registered new interface driver pl2303 [ 0.705508] usbserial: USB Serial support registered for pl2303 [ 0.705592] booke_wdt: powerpc book-e watchdog driver loaded [ 0.705769] sdhci: Secure Digital Host Controller Interface driver [ 0.705849] sdhci: Copyright(c) Pierre Ossman [ 0.705906] sdhci-pltfm: SDHCI platform and OF driver helper [ 0.706033] mmc0: Invalid maximum block size, assuming 512 bytes [ 0.706112] mmc0 bounce up to 128 segments into one, max segment size 65536 b ytes [ 0.731266] mmc0: SDHCI controller on 10020c0000.emmc [10020c0000.emmc] using DMA [ 0.731422] oprofile: using timer interrupt. [ 0.731546] Initializing XFRM netlink socket [ 0.731789] NET: Registered protocol family 10 [ 0.732013] Segment Routing with IPv6 [ 0.732096] sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver [ 0.732331] NET: Registered protocol family 17 [ 0.732414] sctp: Hash tables configured (bind 1024/1024) [ 0.732591] Key type dns_resolver registered [ 0.732698] drmem: No dynamic reconfiguration memory found [ 0.732888] hctosys: unable to open rtc device (rtc0) [ 0.734057] Freeing unused kernel memory: 2080K [ 0.734116] This architecture does not have kernel memory protection. [ 0.734199] Run /init as init process > > The difference with this commit is that if there are several > memblocks, all get mapped. Maybe your > target doesn't like it. > > You are talking about simulation, are you using QEMU ? If yes can you > provide details so that I can > try and reproduce the issue ? No, we use Windriver simics for this system. I'm not sure if QEMU has a model for the PPC476... and I suspect it won't recreate with a more generic 32 bit ppc machine, though I can try and find out. Thanks, Eddie > > Thanks > Christophe
