Re: [mm] c566586818: BUG:kernel_hang_in_early-boot_stage,last_printk:Probing_EDD(edd=off_to_disable)...ok

[Rong Chen]

On 8/21/20 9:01 AM, Qian Cai wrote:
> On Tue, Aug 18, 2020 at 08:23:51AM +0800, kernel test robot wrote:
> > Greeting,
> >
> > FYI, we noticed the following commit (built with gcc-9):
> >
> > commit: c5665868183fec689dbab9fb8505188b2c4f0757 ("mm: kmemleak: use the memory pool for early allocations")
> I might see one of those early boot failure before. In my case, the bare-metal
> system was reset. Can you try to narrow down to a smaller
> CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE (assume 0 works if your bisecting was
> correct) that works?

Hi Qian,

Adding CONFIG_EARLY_PRINTK=y to the kconfig file, and the boot hangs in 
the below position:

[    0.715834] Kernel command line: root=/dev/ram0 hung_task_panic=1 
debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 
net.ifnames=0 printk.devkmsg=on panic=-1 softlockup_panic=1 
nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 
drbd.minor_count=8
systemd.log_level=err ignore_loglevel console=tty0 
earlyprintk=ttyS0,115200 console=ttyS0,115200 vga=normal rw 
rcuperf.shutdown=0 watchdog_thresh=60
[    0.719688] sysrq: sysrq always enabled.
[    0.801005] Dentry cache hash table entries: 2097152 (order: 12, 
16777216 bytes, linear)
[    0.805588] Inode-cache hash table entries: 1048576 (order: 11, 
8388608 bytes, linear)
[    0.806464] mem auto-init: stack:off, heap alloc:on, heap free:off
[    1.080978] Memory: 12319196K/12680692K available (10243K kernel 
code, 2414K rwdata, 8184K rodata, 856K init, 20772K bss, 361496K 
reserved, 0K cma-reserved)
qemu-system-x86_64: terminating on signal 2

The problem disappeared if CONFIG_DEBUG_KMEMLEAK_MEM_POOL_SIZE=400:

[    1.064575] Kernel command line: root=/dev/ram0 hung_task_panic=1 
debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 
net.ifnames=0 printk.devkmsg=on panic=-1 softlockup_panic=1 
nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 
drbd.minor_count=8
systemd.log_level=err ignore_loglevel console=tty0 
earlyprintk=ttyS0,115200 console=ttyS0,115200 vga=normal rw 
rcuperf.shutdown=0 watchdog_thresh=60
[    1.068883] sysrq: sysrq always enabled.
[    1.108720] Dentry cache hash table entries: 2097152 (order: 12, 
16777216 bytes, linear)
[    1.148852] Inode-cache hash table entries: 1048576 (order: 11, 
8388608 bytes, linear)
[    1.150271] mem auto-init: stack:off, heap alloc:on, heap free:off
[    1.835309] Memory: 12325340K/12680692K available (10243K kernel 
code, 2414K rwdata, 8192K rodata, 856K init, 14628K bss, 355352K 
reserved, 0K cma-reserved)
[    3.487078] general protection fault: 0000 [#1] DEBUG_PAGEALLOC PTI
[    3.488185] CPU: 0 PID: 0 Comm: swapper Not tainted 
5.3.0-11792-gc5665868183fe #1
[    3.489581] RIP: 0010:lookup_address_in_pgd+0xd1/0x158
[    3.490566] Code: 80 e0 01 0f 84 a7 00 00 00 49 89 f0 b8 11 ff ff 01 
48 21 f9 49 c1 e8 12 48 c1 e0 27 41 81 e0 f8 0f 00 00 49 01 c0 49 8d 04 
08 <48> f7 00 9f ff ff ff 0f 84 34 ff ff ff c7 02 02 00 00 00 48 8b 38
[    3.494020] RSP: 0000:ffffffff8239e700 EFLAGS: 00010086
[    3.494959] RAX: ffff110302110d90 RBX: 0000000000000001 RCX: 
ffff888302110000
[    3.496222] RDX: ffffffff8239e72c RSI: ffff88833653b000 RDI: 
ffff88833653a000
[    3.497363] RBP: ffffffff8239e808 R08: ffff888000000d90 R09: 
0000000000346000
[    3.498467] R10: 0000000000000001 R11: 0000000000000000 R12: 
0000000000000001
[    3.499554] R13: 0000000000000000 R14: ffff88833653b000 R15: 
0000000000000000
[    3.500638] FS:  0000000000000000(0000) GS:ffffffff8243d000(0000) 
knlGS:0000000000000000
[    3.501863] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    3.503036] CR2: ffff8883447ff000 CR3: 0000000002420000 CR4: 
00000000000006b0
[    3.504116] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 
0000000000000000
[    3.505156] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 
0000000000000400
[    3.506225] Call Trace:
[    3.506597] Modules linked in:
[    3.507255] random: get_random_bytes called from 
init_oops_id+0x1d/0x2c with crng_init=0
[    3.508734] ---[ end trace 0000000000000000 ]---


Best Regards,
Rong Chen