Hi Angelo, On 05/09/17 00:42, Angelo Dureghello wrote: > On 04/09/2017 08:08, Greg Ungerer wrote: >> I have attached a patch with a slightly different approach to >> fixing this. Can you try this one out? >> >> I have a feel for what is going on, based in particular on >> the changes you made in 0002-m68k-fix-mmu-for-coldfire-mcf5441x.patch. >> I see that the virt_node_shift and accessing pg_data_map when >> not 0 based is going to be problematic with the code as it is. >> >> > Great catch, the patch works,
Thats great, thanks for trying that out. > i maintaind btw the > > memset(NODE_DATA(node), 0, sizeof(pg_data_t)); > > inside void __init m68k_setup_node(int node) since otherwise > there was that warning we've seen initially. Ok, I am not quite sure why you would still need that though. Do you mean the warning about overlaping chunks? Can you send the exact warning output again running this now? >From the code I would have expected that array area to be in the kernel bss and be zeroed out at system startup. (For what it is worth I don't see that warning on my non-zero based test 5475 test config). > About the "cd" issue, it seems to be a hush issue, maybe > becouse hush is built as nommu. Re-executing hush, i can now cd > to a subfolder, but i get then a SEGV on "cd ..". Yeah, maybe that is related to flat format binaries. Normally I run a uClibc ELF based user space with MMU enabled. I'll try with a FLAT format user space and see if I get any problems. Regards Greg > This the boot log: > > ## Booting kernel from Legacy Image at 40001000 ... > Image Name: mainline kernel > Created: 2017-09-04 14:19:47 UTC > Image Type: M68K Linux Kernel Image (uncompressed) > Data Size: 1930976 Bytes = 1.8 MiB > Load Address: 40001000 > Entry Point: 40001000 > Verifying Checksum ... OK > Loading Kernel Image ... OK > [ 0.000000] Linux version 4.13.0-rc7stmark2-001-00039-g96e88773601f-dirty > (angelo@jerusalem) (gcc version 5.2.0 (crosstools-sysam-2016.04.16)) #56 Mon > Sep 4 16:19:46 CEST 2017 > [ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total > pages: 16312 > [ 0.000000] Kernel command line: console=ttyS0,115200 root=/dev/ram0 rw > rootfstype=ramfs rdinit=/bin/init devtmpfs.mount=1 > [ 0.000000] PID hash table entries: 512 (order: -2, 2048 bytes) > [ 0.000000] Dentry cache hash table entries: 16384 (order: 3, 65536 bytes) > [ 0.000000] Inode-cache hash table entries: 8192 (order: 2, 32768 bytes) > [ 0.000000] Sorting __ex_table... > [ 0.000000] Memory: 128288K/131072K available (1219K kernel code, 103K > rwdata, 288K rodata, 264K init, 79K bss, 2784K reserved, 0K cma-reserved) > [ 0.000000] Virtual kernel memory layout: > [ 0.000000] vector : 0x40000000 - 0x40000400 ( 1 KiB) > [ 0.000000] kmap : 0xe0000000 - 0xf0000000 ( 256 MiB) > [ 0.000000] vmalloc : 0xd0000000 - 0xe0000000 ( 256 MiB) > [ 0.000000] lowmem : 0x40000000 - 0x48000000 ( 128 MiB) > [ 0.000000] .init : 0x40196000 - 0x401d8000 ( 264 KiB) > [ 0.000000] .text : 0x40001000 - 0x40131cb0 (1220 KiB) > [ 0.000000] .data : 0x40131cb0 - 0x40193900 ( 392 KiB) > [ 0.000000] .bss : 0x401d86e0 - 0x401ec680 ( 80 KiB) > [ 0.000000] SLUB: HWalign=16, Order=0-3, MinObjects=0, CPUs=1, Nodes=8 > [ 0.000000] NR_IRQS: 256 > [ 0.000000] clocksource: pit: mask: 0xffffffff max_cycles: 0xffffffff, > max_idle_ns: 1019338904850 ns > [ 0.000000] Console: colour dummy device 80x25 > [ 0.070000] Calibrating delay loop... 238.38 BogoMIPS (lpj=1191936) > [ 0.070000] pid_max: default: 32768 minimum: 301 > [ 0.070000] Mount-cache hash table entries: 2048 (order: 0, 8192 bytes) > [ 0.070000] Mountpoint-cache hash table entries: 2048 (order: 0, 8192 > bytes) > [ 0.080000] devtmpfs: initialized > [ 0.090000] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, > max_idle_ns: 19112604462750000 ns > [ 0.090000] futex hash table entries: 256 (order: -2, 3072 bytes) > [ 0.110000] clocksource: Switched to clocksource pit > [ 0.110000] FS-Cache: Loaded > [ 0.380000] workingset: timestamp_bits=27 max_order=14 bucket_order=0 > [ 0.430000] io scheduler noop registered > [ 0.430000] io scheduler deadline registered > [ 0.430000] io scheduler cfq registered (default) > [ 0.430000] io scheduler mq-deadline registered > [ 0.430000] io scheduler kyber registered > [ 0.920000] ColdFire internal UART serial driver > [ 0.920000] mcfuart.0: ttyS0 at MMIO 0xfc060000 (irq = 90, base_baud = > 7500000) is a ColdFire UART > [ 1.110000] console [ttyS0] enabled > [ 1.110000] mcfuart.0: ttyS1 at MMIO 0xfc064000 (irq = 91, base_baud = > 7500000) is a ColdFire UART > [ 1.120000] mcfuart.0: ttyS2 at MMIO 0xfc068000 (irq = 92, base_baud = > 7500000) is a ColdFire UART > [ 1.130000] mcfuart.0: ttyS3 at MMIO 0xfc06c000 (irq = 93, base_baud = > 7500000) is a ColdFire UART > [ 1.150000] random: get_random_bytes called from init_oops_id+0x26/0x46 > with crng_init=0 > [ 1.160000] Freeing unused kernel memory: 264K > [ 1.170000] This architecture does not have kernel memory protection. > [ 1.410000] random: fast init done > > / # > > >> On 02/09/17 08:08, Angelo Dureghello wrote: >>> about my patch sent yesterday, unfortunately, i found btw >>> at least 1 issue: the busybox "cd" doesn't change directory :) >>> >>> / # cat /proc/vmallocinfo >>> 0xd0006000-0xd000c000 24576 n_tty_open+0x16/0xae pages=2 vmalloc >>> / # ls >>> bin etc lib mnt proc sbin usr >>> dev home media opt root sys var >>> / # cd bin >>> / # ls >>> bin etc lib mnt proc sbin usr >>> dev home media opt root sys var >>> / # cat /proc/vm >>> vmallocinfo vmstat >>> / # cat /proc/vm >>> vmallocinfo vmstat >>> / # cat /proc/vmallocinfo >>> 0xd0000000-0xd0006000 24576 unpurged vm_area >>> 0xd0006000-0xd000c000 24576 n_tty_open+0x16/0xae pages=2 vmalloc >>> >>> And after each "cd" attempt, another "unpurged" message is added. >>> Removing MMU cd works as expected. >> >> I setup a configuration with my 5475 where I moved the build >> RAM base to be 32MB - so it was no longer 0 based. Then I could run >> some tests to at least simulate what you have on the 54411. (The >> only catch is my code could still access 0 and surrounding memory >> addresses without faulting...) >> >> Running with my attached patch I didn't see any odd behavior with >> cd/ls like you see above. >> >> Geert: interested if you have any thoughts on problems around >> virt_to_node_shift. Changing CONFIG_RAMBASE I don't think is >> going to resolve the problem in m68k_setup_node(). We access >> of the end of the array since it was divided up based on the >> size of the RAM, but we access it using an index derrived >> directly from the absolute address. >> >> >>> On 01/09/2017 15:30, Geert Uytterhoeven wrote: >>>> Hi Greg, >>>> >>>> On Fri, Sep 1, 2017 at 3:21 PM, Greg Ungerer <[email protected]> >>>> wrote: >>>>> On 01/09/17 17:49, Geert Uytterhoeven wrote: >>>>>> On Fri, Sep 1, 2017 at 12:38 AM, Angelo Dureghello <[email protected]> >>>>>> wrote: >>>>>>> did some additional study and tests. >>>>>>> >>>>>>> Actually i cannot find any simpler patch, i just adjusted it a >>>>>>> bit. I believe this patch will work on your cpu with 0-based >>>>>>> memoryas well. >>>>>>> I attach it for your comments. >>>>>> >>>>>> >>>>>> I think your issue is caused by arch/m68k/include/asm/page_offset.h: >>>>>> >>>>>> #if defined(CONFIG_RAMBASE) >>>>>> #define PAGE_OFFSET_RAW CONFIG_RAMBASE >>>>>> #elif defined(CONFIG_SUN3) >>>>>> #define PAGE_OFFSET_RAW 0x0E000000 >>>>>> #else >>>>>> #define PAGE_OFFSET_RAW 0x00000000 >>>>>> #endif >>>>>> >>>>>> and arch/m68k/Kconfig.machine: >>>>>> >>>>>> if !MMU || COLDFIRE >>>>>> >>>>>> config RAMBASE >>>>>> hex "Address of the base of RAM" >>>>>> default "0" >>>>>> >>>>>> So on MC680[2346]0 with MMU (and ignoring Sun-3, which is special), >>>>>> PAGE_OFFSET == PAGE_OFFSET_RAW == 0. >>>>>> >>>>>> On Greg's zero-based Coldfire with MMU, CONFIG_RAMBASE is zero, and thus >>>>>> PAGE_OFFSET is also zero. >>>>>> >>>>>> On your board CONFIG_RAMBASE is non-zero, hence PAGE_OFFSET is also >>>>>> non-zero, >>>>>> and thus you have to compensate for that, cfr. your second patch. >>>>>> >>>>>> Does it work if you force PAGE_OFFSET_RAW to zero? >>>>>> >>>>>> If yes, we either need: >>>>>> >>>>>> --- a/arch/m68k/include/asm/page_offset.h >>>>>> +++ b/arch/m68k/include/asm/page_offset.h >>>>>> @@ -1,6 +1,6 @@ >>>>>> /* This handles the memory map.. */ >>>>>> >>>>>> -#if defined(CONFIG_RAMBASE) >>>>>> +#if !defined(CONFIG_MMU) >>>>>> #define PAGE_OFFSET_RAW CONFIG_RAMBASE >>>>>> #elif defined(CONFIG_SUN3) >>>>>> #define PAGE_OFFSET_RAW 0x0E000000 >>>>>> >>> >>> I tested this patch, (removed mine) and kernel hangs somewhere silently at >>> first init, i don't have the debug enabled now, but i suspect it still >>> hangs at some initial "memset" since 0 area for kernel should >>> be allocated before access. >>> >>> Isn't PAGE_OFFSET the starting area for the virtual kernel address space ? >>> At least so it seems to be for the famous 3G + 1G of x86. >> >> Well, for the current working ColdFire with MMU that is the case. >> The kernel virtual addresses start at 0... >> >> >>> This is what i see at boot with my patch of yesterday: >>> >>> [ 0.000000] Virtual kernel memory layout: >>> [ 0.000000] vector : 0x40000000 - 0x40000400 ( 1 KiB) >>> [ 0.000000] kmap : 0xe0000000 - 0xf0000000 ( 256 MiB) >>> [ 0.000000] vmalloc : 0xd0000000 - 0xe0000000 ( 256 MiB) >>> [ 0.000000] lowmem : 0x40000000 - 0x48000000 ( 128 MiB) >>> [ 0.000000] .init : 0x40196000 - 0x401d8000 ( 264 KiB) >>> [ 0.000000] .text : 0x40001000 - 0x40131e70 (1220 KiB) >>> [ 0.000000] .data : 0x40131e70 - 0x40193900 ( 391 KiB) >>> [ 0.000000] .bss : 0x401d86d8 - 0x401ec680 ( 80 KiB) >> >> For whatever it is worth this is what I see now on my debug setup: >> >> Virtual kernel memory layout: >> vector : 0x02000000 - 0x02000400 ( 1 KiB) >> kmap : 0xe0000000 - 0xf0000000 ( 256 MiB) >> vmalloc : 0xd0000000 - 0xe0000000 ( 256 MiB) >> lowmem : 0x02000000 - 0x04000000 ( 32 MiB) >> .init : 0x02288000 - 0x02296000 ( 56 KiB) >> .text : 0x02020000 - 0x0221f270 (2045 KiB) >> .data : 0x0221f270 - 0x02284140 ( 404 KiB) >> .bss : 0x022967a0 - 0x022ae60c ( 96 KiB) >> >> Regards >> Greg >> >> >> >>>>>> or >>>>>> >>>>>> --- a/arch/m68k/Kconfig.machine >>>>>> +++ b/arch/m68k/Kconfig.machine >>>>>> @@ -325,6 +325,7 @@ comment "RAM configuration" >>>>>> >>>>>> config RAMBASE >>>>>> hex "Address of the base of RAM" >>>>>> + depends on MMU >>>>> >>>>> >>>>> Did you mean "depends on !MMU" here? >>>> >>>> Sorry, yes, depends on !MMU. >>>> >>>>>> depending on whether anything else in the Coldfire code needs RAMBASE. >>>>> >>>>> There are a couple of places we depend on CONFIG_RAMBASE even >>>>> when running with the MMU enabled. Most importantly in setting >>>>> the cachable regions in arch/m68k/include/asm/m54xxacr.h. >>>>> So this is probably not going to work on its own. >>>> >>>> OK, as I already feared/expected... >>>> >>>>> But the first patch above should be ok. It should certainly work on >>>>> my 0 address base 5475 ColdFire setup. Angelo can you try that one? >>>> >>>> Right. >>>> >>>> Gr{oetje,eeting}s, >>>> >>>> Geert >>>> >>>> -- >>>> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- >>>> [email protected] >>>> >>>> In personal conversations with technical people, I call myself a hacker. >>>> But >>>> when I'm talking to journalists I just say "programmer" or something like >>>> that. >>>> -- Linus Torvalds >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-m68k" in >>>> the body of a message to [email protected] >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>> >>> >>> Regards, >>> Angelo >>> >> > > Regards, > Angelo > -- To unsubscribe from this list: send the line "unsubscribe linux-m68k" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
