Re: [PATCH v2 00/48] ARM: PXA multiplatform support

[Arnd Bergmann <arnd@arndb.de>]

On Mon, May 2, 2022 at 10:35 PM Guenter Roeck <linux@roeck-us.net> wrote:
> On 5/2/22 12:21, Arnd Bergmann wrote:
> >
>
> To boot from initrd:
>
> qemu-system-arm -M z2 -kernel \
>       arch/arm/boot/zImage -no-reboot -initrd \
>       rootfs-armv5.cpio --append \
>       "panic=-1 slub_debug=FZPUA rdinit=/sbin/init console=ttyS0" -nographic \
>       -monitor null -serial stdio
>
> where rootfs-armv5.cpio is from my repository at github.com.
>
> https://github.com/groeck/linux-build-test/blob/master/rootfs/arm/rootfs-armv5.cpio.gz
>

Ok, that works here with any configuration, I don't see a regression.
Could this be a problem with the size increase? The machine only has
32MB of RAM, so it's possible that the multiplatform-enabled kernel
with DT support etc pushes it over the edge, especially with an initramfs.

My configuration is clearly a bit different from yours, so I tried giving it
a larger initramfs file, which randomly crashes elsewhere for me:

[    0.648659] pxa2xx-uart.0: ttyS0 at MMIO 0x40100000 (irq = 38,
base_baud = 928571) is a UART1
[    0.697984] kworker/u2:0 invoked oom-killer:
gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0
[    0.698278] CPU: 0 PID: 7 Comm: kworker/u2:0 Not tainted
5.18.0-rc1-00109-gee927ad51300-dirty #52
[    0.698382] Hardware name: Zipit Z2
[    0.698520] Workqueue: events_unbound async_run_entry_fn
[    0.699063]  unwind_backtrace from show_stack+0x18/0x1c
[    0.699148]  show_stack from dump_header+0x68/0x254
[    0.699186]  dump_header from out_of_memory+0x474/0x4f0
[    0.699208]  out_of_memory from __alloc_pages+0xa0c/0xb84
[    0.699227]  __alloc_pages from shmem_getpage_gfp.constprop.0+0x270/0x9e0
[    0.699247]  shmem_getpage_gfp.constprop.0 from
generic_perform_write+0xd8/0x210
[    0.699268]  generic_perform_write from __generic_file_write_iter+0x130/0x198
[    0.699286]  __generic_file_write_iter from generic_file_write_iter+0x64/0xd0
[    0.699302]  generic_file_write_iter from __kernel_write+0x114/0x2b0
[    0.699321]  __kernel_write from kernel_write+0x68/0x194
[    0.699337]  kernel_write from xwrite+0x3c/0x78
[    0.699363]  xwrite from do_copy+0xc0/0x11c
[    0.699381]  do_copy from write_buffer+0x2c/0x44
[    0.699397]  write_buffer from flush_buffer+0x3c/0xa0
[    0.699413]  flush_buffer from __gunzip+0x2a4/0x364
[    0.699434]  __gunzip from gunzip+0x2c/0x34
[    0.699449]  gunzip from unpack_to_rootfs+0x19c/0x304
[    0.699465]  unpack_to_rootfs from do_populate_rootfs+0x6c/0x1dc
[    0.699483]  do_populate_rootfs from async_run_entry_fn+0x44/0x1a0
[    0.699502]  async_run_entry_fn from process_one_work+0x1e8/0x544
[    0.699520]  process_one_work from worker_thread+0x34/0x578
[    0.699579]  worker_thread from kthread+0xdc/0x114
[    0.699599]  kthread from ret_from_fork+0x14/0x2c
[    0.699651] Exception stack(0xc2821fb0 to 0xc2821ff8)
[    0.699711] 1fa0:                                     00000000
00000000 00000000 00000000
[    0.699731] 1fc0: 00000000 00000000 00000000 00000000 00000000
00000000 00000000 00000000
[    0.699744] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[    0.699801] Mem-Info:
[    0.699889] active_anon:90 inactive_anon:674 isolated_anon:0
[    0.699889]  active_file:0 inactive_file:0 isolated_file:0
[    0.699889]  unevictable:0 dirty:0 writeback:0
[    0.699889]  slab_reclaimable:0 slab_unreclaimable:1691
[    0.699889]  mapped:0 shmem:771 pagetables:0 bounce:0
[    0.699889]  kernel_misc_reclaimable:0
[    0.699889]  free:207 free_pcp:37 free_cma:0
[    0.699986] Node 0 active_anon:360kB inactive_anon:2696kB
active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB
isolated(file):0kB mapped:0kB dirty:0kB writeback:0kB shmem:3084kB
writeback_tmp:0kB kernel_stack:192kB pagetables:0kB all_unreclaimable?
yes
[    0.700116] Normal free:828kB boost:1024kB min:1464kB low:1572kB
high:1680kB reserved_highatomic:0KB active_anon:360kB
inactive_anon:2696kB active_file:0kB inactive_file:0kB unevictable:0kB
writepending:0kB present:32768kB managed:12232kB mlocked:0kB
bounce:0kB free_pcp:148kB local_pcp:148kB free_cma:0kB
[    0.700177] lowmem_reserve[]: 0 0
[    0.700247] Normal: 3*4kB (UM) 2*8kB (UM) 2*16kB (M) 0*32kB 0*64kB
0*128kB 1*256kB (M) 1*512kB (M) 0*1024kB = 828kB

       Arnd