Re: OOM on objtool when building x86_64:allyesconfig on system running v6.1.x kernels

[Guenter Roeck]

On Mon, Jan 23, 2023 at 03:11:03PM -0800, Guenter Roeck wrote:
> Hi all,
> 
> when trying to build x86_64:allyesconfig on a system running v6.1.x kernels
> (currently 6.1.7), I keep getting OOM errors in objtool.
> 
> [360871.492187] objtool invoked oom-killer: gfp_mask=0x140dca(GFP_HIGHUSER_MOVABLE|__GFP_COMP|__GFP_ZERO), order=0, oom_score_adj=0
> [360871.492194] CPU: 4 PID: 1158479 Comm: objtool Not tainted 6.1.7-spi+ #1
> [360871.492196] Hardware name: Micro-Star International Co., Ltd. MS-7B89/B450M MORTAR MAX (MS-7B89), BIOS 2.H0 07/27/2022
> [360871.492198] Call Trace:
> [360871.492199]  <TASK>
> [360871.492202]  dump_stack_lvl+0x49/0x63
> [360871.492206]  dump_stack+0x10/0x16
> [360871.492207]  dump_header+0x4f/0x216
> [360871.492209]  oom_kill_process.cold+0xb/0x10
> [360871.492211]  out_of_memory+0x1cf/0x520
> ...
> [360871.492254] Mem-Info:
> [360871.492256] active_anon:743423 inactive_anon:6755060 isolated_anon:0
>                  active_file:847 inactive_file:1145 isolated_file:0
>                  unevictable:665 dirty:8 writeback:0
>                  slab_reclaimable:475477 slab_unreclaimable:69268
>                  mapped:2213 shmem:760735 pagetables:16035
>                  sec_pagetables:0 bounce:0
>                  kernel_misc_reclaimable:0
>                  free:92647 free_pcp:10 free_cma:0
> ...
> [360871.492446] Out of memory: Killed process 1158479 (objtool) total-vm:25987600kB, anon-rss:25766820kB, file-rss:1444kB, shmem-rss:180kB, UID:1000 pgtables:50464kB oom_score_adj:0
> 
> The system has 32GB of memory. I do not see the problem on other systems
> running v5.15.y kernels, or on the same system before installing a v6.1.x
> kernel. I don't think I have ever seen the problem on the same system
> when trying to build an older kernel either.
> 
> Has anyone else observed a similar problem ? Any idea what might be
> going on, or what I can do to help tracking this down ?
> 

Just to close this: There is nothing special going on ... except
that objtool now requires so much memory (24+ GB) when building
x86_64:allyesconfig that one of my systems simply ran out.
Adding 16GB of swap on that system fixed the problem.

Guenter