Re: Linux 6.18-rc6

[David Hildenbrand (Red Hat)]

On 17.11.25 13:56, David Wang wrote:
> At 2025-11-17 18:33:58, "Linus Torvalds" <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
> > On Mon, 17 Nov 2025 at 00:20, David Wang <00107082@xxxxxxx> wrote:
> > > After upgrade to 6.18-rc6, all my golang programs start to crash, even Go compiler crashes;
> > > and when I started bisect, `make vmlinux` crashes too.
> >
> > Funky funky. Certainly doesn't happen here.
> >
> > > I am running bisect with 6.18-rc5 now, any chance this has already caught/fixed?
> >
> > Please do run the bisect (obviously you'll have to build using a
> > kernel that works for you), I am not aware of anybody reporting
> > anything like this.
>
> Hi,
>
> Bisect narrowed it down to
> [adfb6609c6809e107ded9a1cd46f519c882e64ea] mm/huge_memory: initialise the tags of the huge zero folio
>
> It seems happen to program build with older version of go, mine is 1.18.4;   and I cannot reproduce it with go1.25.4.
>
> When I upgraded to 6.18-rc6,  go1.18.4 compiler/program would crash with,
>
>      fatal error: arena already initialized
>      
>      runtime stack:
>      runtime.throw({0x9ea9fe?, 0x0?})
> 	    /usr/local/go/src/runtime/panic.go:992 +0x71 fp=0x7ffdf458a248 sp=0x7ffdf458a218 pc=0x435ab1
>      runtime.(*mheap).sysAlloc(0xddec20, 0x0?)
> 	    /usr/local/go/src/runtime/malloc.go:749 +0x2e9 fp=0x7ffdf458a2e0 sp=0x7ffdf458a248 pc=0x40dee9
>      ...
>
>
> And when I `make vmlinux`, I got something like this :
> 	  AR      vmlinux.a
> 	  LD      vmlinux.o
> 	  GEN     .vmlinux.objs
> 	  MODPOST vmlinux.symvers
> 	  CC      .vmlinux.export.o
> 	  UPD     include/generated/utsversion.h
> 	  CC      init/version-timestamp.o
> 	  KSYMS   .tmp_vmlinux0.kallsyms.S
> 	  AS      .tmp_vmlinux0.kallsyms.o
> 	  LD      .tmp_vmlinux1
> 	  NM      .tmp_vmlinux1.syms
> 	  KSYMS   .tmp_vmlinux1.kallsyms.S
> 	  AS      .tmp_vmlinux1.kallsyms.o
> 	.tmp_vmlinux1.kallsyms.S:361542:19: internal compiler error: Aborted
> 	361542 |         .byte 0x00, 0x99, 0xe9  /* T__pfx___x64_sys_inotify_add_watch */
> 	       |                   ^
> 	0x7f983a551def ???
> 		./signal/../sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c:0
> 	0x7f983a5a695c __pthread_kill_implementation
> 		./nptl/pthread_kill.c:44
> 	0x7f983a551cc1 __GI_raise
> 		../sysdeps/posix/raise.c:26
> 	0x7f983a53a4ab __GI_abort
> 		./stdlib/abort.c:73
> 	0x7f983a53bca7 __libc_start_call_main
> 		../sysdeps/nptl/libc_start_call_main.h:58
> 	0x7f983a53bd64 __libc_start_main_impl
> 		../csu/libc-start.c:360
> 	Please submit a full bug report, with preprocessed source (by using -freport-bug).
> 	Please include the complete backtrace with any bug report.
> 	See <file:///usr/share/doc/gcc-14/README.Bugs> for instructions.
> 	make[2]: *** [scripts/Makefile.vmlinux:72: vmlinux.unstripped] Error 1
> 	make[1]: *** [/home/linan/codes/linux-kernel/linux/Makefile:1242: vmlinux] Error 2
> 	make: *** [Makefile:248: __sub-make] Error 2
> $ gcc --version
> gcc (Debian 14.2.0-19) 14.2.0
>
> (It dose not always happens, sometimes I don't get this crash and It dose not always err on same line.)
>
> And nothing abnormal shows up in kernel message.
>
> Revert adfb6609c6809e107ded9a1cd46f519c882e64ea can fix my crashing go programs.


I just replied privately to a similar report the following:

Hi,

I observed something similar while testing on Friday between rc4 (good)
and rc5+ (bad).


I'm sure this it the known issue of
adfb6609c6809e107ded9a1cd46f519c882e64ea we discussed already here [1].


@Jan, can you send the fix out today? Otherwise I can take care of this
so we get this fixed asap.

[1] https://lkml.kernel.org/r/20251109003613.1461433-1-japo@xxxxxxxxxxxxx


--
Cheers

David