Re: Build failure for ``no options PTRACE''

[Paul Goyette <paul%whooppee.com@localhost>]

On Sat, 17 Oct 2020, Paul Goyette wrote:

> OK, I updated kern/kern_core.c to #include exec_elf.h and made is past
> the modules.
>
> I'll install in the morning and make sure that all combinations of
> modules from {coredump, exec_elf32, exec_elf64} work.  At the very
> least, they all have to successfully load in any sequence without
> requiring any circular dependencies!

I guess I actually spoke too soon.  #include exec_elf.h allowed me to
compile kern_core.c but it then failed to compile kern/core_elf32.c
with the following errors:

#   compile  coredump/core_elf32.o
/build/netbsd-local/tools/x86_64/amd64/bin/x86_64--netbsd-gcc -O2 -g   -std=gnu99    -Wall -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Wno-sign-compare  -Wsystem-headers   -Wno-traditional   -Wa,--fatal-warnings  -Wreturn-type -Wswitch -Wshadow -Wcast-qual -Wwrite-strings -Wextra -Wno-unused-parameter -Wno-sign-compare -Werror  -Wno-error=address-of-packed-member   -ffreestanding  -fno-strict-aliasing -Wno-pointer-sign -mno-red-zone -mno-mmx -mno-sse -mno-avx -msoft-float -mcmodel=kernel -fno-omit-frame-pointer   -I/build/netbsd-local/src_ro/common/include -DDIAGNOSTIC --sysroot=/build/netbsd-local/dest/amd64 -I/build/netbsd-local/src_ro/common/include -DDIAGNOSTIC  -nostdinc -I. -I/build/netbsd-local/src_ro/sys/modules/coredump -isystem /build/netbsd-local/src_ro/sys -isystem /build/netbsd-local/src_ro/sys/arch -isystem /build/netbsd-local/src_ro/sys/../common/include -D_KERNEL -D_MODULE -DSYSCTL_INCLUDE_DESCR -c    /build/netbsd-local/src_ro/sys/kern/core_elf3
2.c
In file included from /build/netbsd-local/src_ro/sys/kern/core_elf32.c:42:
/build/netbsd-local/src_ro/sys/kern/core_elf32.c: In function 'coredump_note_procinfo':
/build/netbsd-local/src_ro/sys/kern/core_elf32.c:424:13: error: implicit declaration of function 'coredump_savenote_elf32'; did you mean 'coredump_note_elf32'? [-Werror=implicit-function-declaration]
  424 |  ELFNAMEEND(coredump_savenote)(ns, ELF_NOTE_NETBSD_CORE_PROCINFO,
      |             ^~~~~~~~~~~~~~~~~
/build/netbsd-local/src_ro/sys/kern/core_elf32.c: In function 'coredump_note_elf32':
/build/netbsd-local/src_ro/sys/kern/core_elf32.c:541:2: error: 'PT32_GETXSTATE' undeclared (first use in this function); did you mean 'PT64_GETXSTATE'?
  541 |  COREDUMP_MACHDEP_LWP_NOTES(l, ns, d->name);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~
/build/netbsd-local/src_ro/sys/kern/core_elf32.c:541:2: note: each undeclared identifier is reported only once for each function it appears in
/build/netbsd-local/src_ro/sys/kern/core_elf32.c: At top level:
/build/netbsd-local/src_ro/sys/kern/core_elf32.c:583:12: error: no previous prototype for 'coredump_savenote_elf32' [-Werror=missing-prototypes]
  583 | ELFNAMEEND(coredump_savenote)(struct note_state *ns, unsigned int type,
      |            ^~~~~~~~~~~~~~~~~
/build/netbsd-local/src_ro/sys/kern/core_elf32.c:583:12: error: conflicting types for 'coredump_savenote_elf32' [-Werror]
/build/netbsd-local/src_ro/sys/kern/core_elf32.c:424:13: note: previous implicit declaration of 'coredump_savenote_elf32' was here
  424 |  ELFNAMEEND(coredump_savenote)(ns, ELF_NOTE_NETBSD_CORE_PROCINFO,
      |             ^~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
*** [core_elf32.o] Error code 1


I'm getting lost inside all this elf stuff....  :)


> > > Just add their declarations in exec_elf.h they have the same signatures as 
> > > the "unreal" ones :-)
> >
> > Tried that, but now kern_core.c won't compile as part of the coredump
> > module:
> >
> > ...
> > #   compile  coredump/kern_core.o
> > ... (gcc command line elided)
> > In file included from /build/netbsd-local/src_ro/sys/sys/compat_stub.h:35,
> >                 from /build/netbsd-local/src_ro/sys/kern/kern_core.c:53:
> > /build/netbsd-local/src_ro/sys/kern/kern_core.c: In function 
> > 'coredump_modcmd':
> > /build/netbsd-local/src_ro/sys/kern/kern_core.c:80:40: error: 
> > 'real_coredump_elf32' undeclared (first use in this function); did you mean 
> > 'real_coredump_netbsd'?
> >   80 |   MODULE_HOOK_SET(coredump_elf32_hook, real_coredump_elf32);
> >      |                                        ^~~~~~~~~~~~~~~~~~~
> > /build/netbsd-local/src_ro/sys/kern/kern_core.c:80:40: note: each 
> > undeclared identifier is reported only once for each function it appears in
> > /build/netbsd-local/src_ro/sys/kern/kern_core.c:81:40: error: 
> > 'real_coredump_elf64' undeclared (first use in this function); did you mean 
> > 'real_coredump_netbsd'?
> >   81 |   MODULE_HOOK_SET(coredump_elf64_hook, real_coredump_elf64);
> >      |                                        ^~~~~~~~~~~~~~~~~~~
> > *** [kern_core.o] Error code 1
> >
> >
> > > > > > FWIW, in addition to
> > > > > >
> > > > > > 	no options COREDUMP
> > > > > > 	no options PTRACE
> > > > > > my custom kernel also has
> > > > > >
> > > > > > 	no options EXEC_ELF32
> > > > > > 	no options EXEC_ELF64
> > > > > > These modules are expected to be auto-loaded as necessary.
> > > > > > It seems that the exec_elf* modules fail to load, since the symbol
> > > > > > coredump_elf{32,64} is already defined in the kernel, even though
> > > > > > I have the ``no options EXEC_ELF*'' in the config.
> > > > > > ...
> > > > > > [   8.0347157] init: copying out path `/sbin/init' 11
> > > > > > [   8.0544213] kobj_checksyms, 1026: [%M/exec_elf32/exec_elf32.kmod]: 
> > > > > > linker error: global symbol `coredump_elf32' redefined
> > > > > > [   8.0544213] WARNING: module error: vfs load failed for `exec_elf32', 
> > > > > > error 8
> > > > > > [   8.0544213] kobj_checksyms, 1026: [%M/exec_elf64/exec_elf64.kmod]: 
> > > > > > linker error: global symbol `coredump_elf64' redefined
> > > > > > [   8.0544213] WARNING: module error: vfs load failed for `exec_elf64', 
> > > > > > error 8
> > > > > > ...

+--------------------+--------------------------+-----------------------+
| Paul Goyette       | PGP Key fingerprint:     | E-mail addresses:     |
| (Retired)          | FA29 0E3B 35AF E8AE 6651 | paul%whooppee.com@localhost     |
| Software Developer | 0786 F758 55DE 53BA 7731 | pgoyette%netbsd.org@localhost   |
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