kern/58215: compat_netbsd32 broken

[martin%NetBSD.org@localhost]

>Number:         58215
>Category:       kern
>Synopsis:       compat_netbsd32 broken
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Apr 30 10:35:00 +0000 2024
>Originator:     Martin Husemann
>Release:        NetBSD 10.99.10
>Organization:
The NetBSD Foundation, Inc.
>Environment:
System: NetBSD seven-days-to-the-wolves.aprisoft.de 10.99.10 NetBSD 10.99.10 (GENERIC) #692: Tue Apr 30 09:57:26 CEST 2024 martin%seven-days-to-the-wolves.aprisoft.de@localhost:/work/src/sys/arch/amd64/compile/GENERIC amd64
Architecture: x86_64
Machine: amd64
>Description:

Recently (within the last week) compat_netbsd32 on amd64 broke. This is
from trying to exec a i386 tcsh in a i386 chroot on an amd64 machine running
-current as of a few hours ago:

 26296  26296 tcsh     CALL  netbsd32___sigprocmask14(1,0xfff9a2f4,0xfff9a2e4)
 26296  26296 tcsh     RET   netbsd32___sigprocmask14 0
 26296  26296 tcsh     CALL  netbsd32___sigsuspend14(0xfff9a304)
 26296  26296 tcsh     RET   netbsd32___sigsuspend14 -1 errno 4 Interrupted system call
 26296  26296 tcsh     PSIG  SIGCHLD caught handler=0x808bace mask=(2,20): code=CLD_EXITED child pid=15948, uid=0,  status=0, utime=0, stime=0)
 26296  26296 tcsh     CALL  compat_16_netbsd32___sigreturn14(0xfff9a260)
 26296  26296 tcsh     RET   compat_16_netbsd32___sigreturn14 -1 errno 78 Function not implemented
 26296  26296 tcsh     PSIG  SIGSYS SIG_DFL: code=SI_NOINFO
 26296  26296 tcsh     NAMI  "tcsh.core"


The same works on aarch64, both tcsh binaries are a bit oldish, both (base)
userlands are up to date (as of a few hours ago):

tcsh: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /usr/libexec/ld.elf_so, for NetBSD 9.99.82, stripped
tcsh: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /usr/libexec/ld.elf_so, for NetBSD 9.99.80, compiled for: earmv7hf, stripped


>How-To-Repeat:

s/a

>Fix:
n/a