Re: [PATCH v5 0/8] unwind, arm64: add sframe unwinder for kernel

[Brian Norris <briannorris@chromium.org>]

Hi Jens,

Thanks for looking! Lots more output below. Feel free to ask for more
info you tink could help.`

On Wed, Jul 15, 2026 at 10:06:20AM +0200, Jens Remus wrote:
> On 7/14/2026 2:28 AM, Brian Norris wrote:
> > On Tue, May 19, 2026 at 01:05:23PM +0200, Jens Remus wrote:
> 
> > I also work at the same company as Dylan and Mostafa, and am therefore
> > probably using the same company-maintained Linux distribution.
> > 
> >> On 5/18/2026 7:55 PM, Dylan Hatch wrote:
> >>> On Fri, May 15, 2026 at 4:32 AM Mostafa Saleh <smostafa@google.com> wrote:
> >>>> Not sure if related, but after updating my toolchain
> >>>> (aarch64-linux-gnu-gcc (Debian 15.2.0-4) 15.2.0), I hit link errors:
> >>>> ld.lld: error: arch/arm64/kernel/vdso/vgettimeofday.o:(.sframe) is being placed in '.sframe'
> >>>> ld.lld: error: arch/arm64/kernel/vdso/vgetrandom.o:(.sframe) is being placed in '.sframe`
> 
> My understanding of above message is that the linker complains that the
> input object (e.g. vgettimeofday.o) has an .sframe section for which
> the linker script does not have any rule, so that it defaults to place
> it in .sframe in the output, which could not be the desired result.

Not sure if it's obvious to you, but I also found a few more details:

* This is most noticeable with CONFIG_WERROR=y, which turns the linker
  warning into an error.

* It appears both with LD=ld.lld and with the default (bfd linker). bfd
  shows:

/usr/bin/aarch64-linux-gnu-ld.bfd: error: unplaced orphan section `.sframe' from `arch/arm64/kernel/vdso/vgettimeofday.o'
/usr/bin/aarch64-linux-gnu-ld.bfd: error: unplaced orphan section `.sframe' from `arch/arm64/kernel/vdso/vgetrandom.o'


Otherwise, I don't have to do much special to hit this. Just
cross-compile ARCH=arm64 defconfig.

> > I've also been hitting this for some time, and I'd like to see if I can
> > figure out what's going wrong. My current workaround is:
> > 
> > --- a/Makefile
> > +++ b/Makefile
> > @@ -946,6 +946,8 @@ ifdef CONFIG_CC_IS_GCC
> >  KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
> >  KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
> >  endif
> > +# No sframe generation for kernel if enabled by default
> > +KBUILD_CFLAGS	+= $(call cc-option,-Xassembler --gsframe=no)
> >  
> >  ifdef CONFIG_READABLE_ASM
> >  # Disable optimizations that make assembler listings hard to read.
> > 
> >>> Previously when developing against the SFrame V2 format, I had fixed
> >>> these warnings with the VDSO Makefile change currently in this series:
> >>>
> >>> diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
> >>> index 7dec05dd33b7..c60ef921956f 100644
> >>> --- a/arch/arm64/kernel/vdso/Makefile
> >>> +++ b/arch/arm64/kernel/vdso/Makefile
> >>> @@ -38,7 +38,7 @@ ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
> >>>  CC_FLAGS_REMOVE_VDSO := $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \
> >>>                         $(RANDSTRUCT_CFLAGS) $(KSTACK_ERASE_CFLAGS) \
> >>>                         $(GCC_PLUGINS_CFLAGS) \
> >>> -                       $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) \
> >>> +                       $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) $(CC_FLAGS_SFRAME) \
> >>>                         -Wmissing-prototypes -Wmissing-declarations
> >>>
> >>>  CC_FLAGS_ADD_VDSO := -O2 -mcmodel=tiny -fasynchronous-unwind-tables
> >>>
> >>> But the warnings seem to have returned after upgrading my toolchain,
> >>> possibly due to SFrame V3 or some confounding change in GCC. The
> >>> --gsframe in the assembler should be set to 'no' by default, so
> >>> perhaps GCC is providing an override --gsframe internally?
> >>
> >> Could it be that your build of binutils was configured with
> >> --enable-default-sframe, so that the GNU assembler defaults to generate
> >> .sframe?  AFAIK this configure option was meant for distributors and
> >> package maintainers.
> >>
> >> You can check as follows whether --gsframe defaults to "no" or "yes":
> >>
> >> $ as --help | grep -A1 gsframe
> >>   --gsframe[={no|yes}]    whether to generate SFrame stack trace information
> >>                           (default: no)
> >> ...
> > 
> > $ aarch64-linux-gnu-as --help | grep -A1 gsframe
> >   --gsframe[={no|yes}]    whether to generate SFrame stack trace information
> >                           (default: no)
> > --
> >   --gsframe-<N>           generate SFrame version <N> information. 3 == <N>
> >   --scfi=experimental     Synthesize DWARF CFI for hand-written asm
> > 
> >> Maybe build the VDSO separately with V=1 to see what assembler/compiler
> >> options are effectively used (e.g. for vgettimeofday.o and vgetrandom.o
> >> mentioned in the linker error message above)?
> > 
> > A slightly tweaked version of my vgetrandom.o build line:
> > 
> > # CC      arch/arm64/kernel/vdso/vgetrandom.o
> >   aarch64-linux-gnu-gcc -Wp,-MMD,arch/arm64/kernel/vdso/.vgetrandom.o.d -nostdinc -I./arch/arm64/include -I./arch/arm64/include/generated -I./include -I./include -I./arch/arm64/include/uapi -I./arch/arm64/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/compiler-version.h -include ./include/linux/kconfig.h -include ./include/linux/compiler_types.h -D__KERNEL__ -mlittle-endian -DCC_USING_PATCHABLE_FUNCTION_ENTRY -DKASAN_SHADOW_SCALE_SHIFT= -Werror -fshort-wchar -funsigned-char -fno-common -fno-PIE -fno-strict-aliasing -std=gnu11 -fms-extensions -mgeneral-regs-only -DCONFIG_CC_HAS_K_CONSTRAINT=1 -Wno-psabi -mabi=lp64 -fno-asynchronous-unwind-tables -fno-unwind-tables -mbranch-protection=pac-ret -Wa,-march=armv8.5-a -DARM64_ASM_ARCH='"armv8.5-a"' -DKASAN_SHADOW_SCALE_SHIFT= -fno-delete-null-pointer-checks -O2 -fno-allow-store-data-races -fstack-protector-strong -fno-omit-frame-pointer -fno-optimize-sibling-calls -ftrivial-auto-var-init=zero -fzero-init-padding-bits=all -fno-stack-clash-protection -fno-inline-functions-called-once -fmin-function-alignment=8 -fstrict-flex-arrays=3 -fno-strict-overflow -fno-stack-check -fconserve-stack -fno-builtin-wcslen -Wall -Wextra -Wundef -Werror=implicit-function-declaration -Werror=implicit-int -Werror=return-type -Werror=strict-prototypes -Wno-format-security -Wno-trigraphs -Wno-frame-address -Wno-address-of-packed-member -Wframe-larger-than=2048 -Wno-main -Wno-type-limits -Wno-dangling-pointer -Wvla-larger-than=1 -Wno-pointer-sign -Wcast-function-type -Wno-unterminated-string-initialization -Wno-array-bounds -Wno-stringop-overflow -Wno-alloc-size-larger-than -Wimplicit-fallthrough=5 -Werror=date-time -Werror=incompatible-pointer-types -Werror=designated-init -Wenum-conversion -Wunused -Wno-unused-but-set-variable -Wno-unused-const-variable -Wno-packed-not-aligned -Wno-format-overflow -Wno-format-truncation -Wno-stringop-truncation -Wno-override-init -Wno-missing-field-initializers -Wno-shift-negative-value -Wno-maybe-uninitialized -Wno-sign-compare -Wno-unused-parameter -g -mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=1344 -fno-common -fno-builtin -fno-stack-protector -ffixed-x18 -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO -O2 -mcmodel=tiny -fasynchronous-unwind-tables -include ./lib/vdso/getrandom.c   -I./arch/arm64/kernel/vdso -Iarch/arm64/kernel/vdso    -DKBUILD_MODFILE='"arch/arm64/kernel/vdso/vgetrandom"' -DKBUILD_BASENAME='"vgetrandom"' -DKBUILD_MODNAME='"vgetrandom"' -D__KBUILD_MODNAME=vgetrandom -c -o arch/arm64/kernel/vdso/vgetrandom.o ./arch/arm64/kernel/vdso/vgetrandom.c
> 
> That command line does not have any --gsframe[-3] (e.g. -Wa,--gsframe).
> I am not aware of any binutils release / repository state where the
> --gsframe default was broken.

FWIW, I'm usually testing on both v7.1 and approx v7.2-rc3, to make sure
my results are consistent, and it's not already somehow fixed.

> @Indu: Do you have any idea what could be going on?
> 
> > I mostly don't know what I'm looking for w.r.t. gsframe features, but
> > I'm willing to poke at my compiler/assembler/build-process.
> 
> Could it be that your gcc injects --gsframe e.g. via its spec file?
> Maybe that would show up if you run above command manually and append
> gcc option -v?

I've dumped most of the output below. I see that the 'as' invocation
includes --gsframe, but I'm not sure why.

$ aarch64-linux-gnu-gcc -Wp,-MMD,arch/arm64/kernel/vdso/.vgetrandom.o.d -nostdinc -I./arch/arm64/include -I./arch/arm64/include/generated -I./include -I./include -I./arch/arm64/include/uapi -I./arch/arm64/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/compiler-version.h -include ./include/linux/kconfig.h -include ./include/linux/compiler_types.h -D__KERNEL__ -mlittle-endian -DKASAN_SHADOW_SCALE_SHIFT= -Werror -fshort-wchar -funsigned-char -fno-common -fno-PIE -fno-strict-aliasing -std=gnu11 -fms-extensions -mgeneral-regs-only -DCONFIG_CC_HAS_K_CONSTRAINT=1 -Wno-psabi -mabi=lp64 -fno-asynchronous-unwind-tables -fno-unwind-tables -mbranch-protection=pac-ret -Wa,-march=armv8.5-a -DARM64_ASM_ARCH='"armv8.5-a"' -DKASAN_SHADOW_SCALE_SHIFT= -fno-delete-null-pointer-checks -O2 -fno-allow-store-data-races -fstack-protector-strong -fno-omit-frame-pointer -fno-optimize-sibling-calls -ftrivial-auto-var-init=zero -fzero-init-padding-bits=all -fno-stack-clash-protection -fmin-function-alignment=4 -fstrict-flex-arrays=3 -fno-strict-overflow -fno-stack-check -fconserve-stack -fno-builtin-wcslen -Wall -Wextra -Wundef -Werror=implicit-function-declaration -Werror=implicit-int -Werror=return-type -Werror=strict-prototypes -Wno-format-security -Wno-trigraphs -Wno-frame-address -Wno-address-of-packed-member -Wframe-larger-than=2048 -Wno-main -Wno-type-limits -Wno-dangling-pointer -Wvla-larger-than=1 -Wno-pointer-sign -Wcast-function-type -Wno-unterminated-string-initialization -Wno-array-bounds -Wno-stringop-overflow -Wno-alloc-size-larger-than -Wimplicit-fallthrough=5 -Werror=date-time -Werror=incompatible-pointer-types -Werror=designated-init -Wenum-conversion -Wunused -Wno-unused-but-set-variable -Wno-unused-const-variable -Wno-packed-not-aligned -Wno-format-overflow -Wno-format-truncation -Wno-stringop-truncation -Wno-override-init -Wno-missing-field-initializers -Wno-shift-negative-value -Wno-maybe-uninitialized -Wno-sign-compare -Wno-unused-parameter -g -fno-var-tracking -femit-struct-debug-baseonly -mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=1344 -fno-common -fno-builtin -fno-stack-protector -ffixed-x18 -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO -O2 -mcmodel=tiny -fasynchronous-unwind-tables -include $LINUX/lib/vdso/getrandom.c    -DKBUILD_MODFILE='"arch/arm64/kernel/vdso/vgetrandom"' -DKBUILD_BASENAME='"vgetrandom"' -DKBUILD_MODNAME='"vgetrandom"' -D__KBUILD_MODNAME=vgetrandom -c -o arch/arm64/kernel/vdso/vgetrandom.o arch/arm64/kernel/vdso/vgetrandom.c  -v
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COLLECT_GCC_OPTIONS='-nostdinc' '-I' './arch/arm64/include' '-I' './arch/arm64/include/generated' '-I' './include' '-I' './include' '-I' './arch/arm64/include/uapi' '-I' './arch/arm64/include/generated/uapi' '-I' './include/uapi' '-I' './include/generated/uapi' '-include' './include/linux/compiler-version.h' '-include' './include/linux/kconfig.h' '-include' './include/linux/compiler_types.h' '-D' '__KERNEL__' '-mlittle-endian' '-D' 'KASAN_SHADOW_SCALE_SHIFT=' '-Werror' '-fshort-wchar' '-funsigned-char' '-fno-PIE' '-fno-strict-aliasing' '-std=gnu11' '-fms-extensions' '-mgeneral-regs-only' '-D' 'CONFIG_CC_HAS_K_CONSTRAINT=1' '-Wno-psabi' '-mabi=lp64' '-fno-unwind-tables' '-mbranch-protection=pac-ret' '-D' 'ARM64_ASM_ARCH="armv8.5-a"' '-D' 'KASAN_SHADOW_SCALE_SHIFT=' '-fno-delete-null-pointer-checks' '-O2' '-fno-allow-store-data-races' '-fstack-protector-strong' '-fno-omit-frame-pointer' '-fno-optimize-sibling-calls' '-ftrivial-auto-var-init=zero' '-fzero-init-padding-bits=all' '-fno-stack-clash-protection' '-fmin-function-alignment=4' '-fstrict-flex-arrays=3' '-fno-strict-overflow' '-fstack-check=no' '-fconserve-stack' '-fno-builtin-wcslen' '-Wall' '-Wextra' '-Wundef' '-Werror=implicit-function-declaration' '-Werror=implicit-int' '-Werror=return-type' '-Werror=strict-prototypes' '-Wno-format-security' '-Wno-trigraphs' '-Wno-frame-address' '-Wno-address-of-packed-member' '-Wframe-larger-than=2048' '-Wno-main' '-Wno-type-limits' '-Wdangling-pointer=0' '-Wvla-larger-than=1' '-Wno-pointer-sign' '-Wcast-function-type' '-Wno-unterminated-string-initialization' '-Warray-bounds=0' '-Wstringop-overflow=0' '-Walloc-size-larger-than=$XXX' '-Wimplicit-fallthrough=5' '-Werror=date-time' '-Werror=incompatible-pointer-types' '-Werror=designated-init' '-Wenum-conversion' '-Wunused' '-Wno-unused-but-set-variable' '-Wunused-const-variable=0' '-Wno-packed-not-aligned' '-Wformat-overflow=0' '-Wformat-truncation=0' '-Wno-stringop-truncation' '-Wno-override-init' '-Wno-missing-field-initializers' '-Wno-shift-negative-value' '-Wno-maybe-uninitialized' '-Wno-sign-compare' '-Wno-unused-parameter' '-g' '-fno-var-tracking' '-femit-struct-debug-baseonly' '-mstack-protector-guard=sysreg' '-mstack-protector-guard-reg=sp_el0' '-mstack-protector-guard-offset=1344' '-fno-common' '-fno-builtin' '-fno-stack-protector' '-ffixed-x18' '-D' 'DISABLE_BRANCH_PROFILING' '-D' 'BUILD_VDSO' '-O2' '-mcmodel=tiny' '-fasynchronous-unwind-tables' '-include' '/usr/local/google/home/briannorris/git/linux/lib/vdso/getrandom.c' '-D' 'KBUILD_MODFILE="arch/arm64/kernel/vdso/vgetrandom"' '-D' 'KBUILD_BASENAME="vgetrandom"' '-D' 'KBUILD_MODNAME="vgetrandom"' '-D' '__KBUILD_MODNAME=vgetrandom' '-c' '-o' 'arch/arm64/kernel/vdso/vgetrandom.o' '-v' '-dumpdir' 'arch/arm64/kernel/vdso/'
 /usr/lib/gcc-cross/aarch64-linux-gnu/15/../../../../aarch64-linux-gnu/bin/as -v -I ./arch/arm64/include -I ./arch/arm64/include/generated -I ./include -I ./include -I ./arch/arm64/include/uapi -I ./arch/arm64/include/generated/uapi -I ./include/uapi -I ./include/generated/uapi --gsframe --gdwarf-5 -EL -mabi=lp64 -march=armv8.5-a -o arch/arm64/kernel/vdso/vgetrandom.o /tmp/cc6nO0fY.s
GNU assembler version 2.46.50 (aarch64-linux-gnu) using BFD version (GNU Binutils for Debian) 2.46.50.20260617
COMPILER_PATH=/usr/libexec/gcc-cross/aarch64-linux-gnu/15/:/usr/libexec/gcc-cross/aarch64-linux-gnu/15/:/usr/libexec/gcc-cross/aarch64-linux-gnu/:/usr/lib/gcc-cross/aarch64-linux-gnu/15/:/usr/lib/gcc-cross/aarch64-linux-gnu/:/usr/lib/gcc-cross/aarch64-linux-gnu/15/../../../../aarch64-linux-gnu/bin/
LIBRARY_PATH=/usr/lib/gcc-cross/aarch64-linux-gnu/15/:/usr/lib/gcc-cross/aarch64-linux-gnu/15/../../../../aarch64-linux-gnu/lib/../lib/:/lib/aarch64-linux-gnu/:/lib/../lib/:/usr/lib/aarch64-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc-cross/aarch64-linux-gnu/15/../../../../aarch64-linux-gnu/lib/:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-nostdinc' '-I' './arch/arm64/include' '-I' './arch/arm64/include/generated' '-I' './include' '-I' './include' '-I' './arch/arm64/include/uapi' '-I' './arch/arm64/include/generated/uapi' '-I' './include/uapi' '-I' './include/generated/uapi' '-include' './include/linux/compiler-version.h' '-include' './include/linux/kconfig.h' '-include' './include/linux/compiler_types.h' '-D' '__KERNEL__' '-mlittle-endian' '-D' 'KASAN_SHADOW_SCALE_SHIFT=' '-Werror' '-fshort-wchar' '-funsigned-char' '-fno-PIE' '-fno-strict-aliasing' '-std=gnu11' '-fms-extensions' '-mgeneral-regs-only' '-D' 'CONFIG_CC_HAS_K_CONSTRAINT=1' '-Wno-psabi' '-mabi=lp64' '-fno-unwind-tables' '-mbranch-protection=pac-ret' '-D' 'ARM64_ASM_ARCH="armv8.5-a"' '-D' 'KASAN_SHADOW_SCALE_SHIFT=' '-fno-delete-null-pointer-checks' '-O2' '-fno-allow-store-data-races' '-fstack-protector-strong' '-fno-omit-frame-pointer' '-fno-optimize-sibling-calls' '-ftrivial-auto-var-init=zero' '-fzero-init-padding-bits=all' '-fno-stack-clash-protection' '-fmin-function-alignment=4' '-fstrict-flex-arrays=3' '-fno-strict-overflow' '-fstack-check=no' '-fconserve-stack' '-fno-builtin-wcslen' '-Wall' '-Wextra' '-Wundef' '-Werror=implicit-function-declaration' '-Werror=implicit-int' '-Werror=return-type' '-Werror=strict-prototypes' '-Wno-format-security' '-Wno-trigraphs' '-Wno-frame-address' '-Wno-address-of-packed-member' '-Wframe-larger-than=2048' '-Wno-main' '-Wno-type-limits' '-Wdangling-pointer=0' '-Wvla-larger-than=1' '-Wno-pointer-sign' '-Wcast-function-type' '-Wno-unterminated-string-initialization' '-Warray-bounds=0' '-Wstringop-overflow=0' '-Walloc-size-larger-than=$XXX' '-Wimplicit-fallthrough=5' '-Werror=date-time' '-Werror=incompatible-pointer-types' '-Werror=designated-init' '-Wenum-conversion' '-Wunused' '-Wno-unused-but-set-variable' '-Wunused-const-variable=0' '-Wno-packed-not-aligned' '-Wformat-overflow=0' '-Wformat-truncation=0' '-Wno-stringop-truncation' '-Wno-override-init' '-Wno-missing-field-initializers' '-Wno-shift-negative-value' '-Wno-maybe-uninitialized' '-Wno-sign-compare' '-Wno-unused-parameter' '-g' '-fno-var-tracking' '-femit-struct-debug-baseonly' '-mstack-protector-guard=sysreg' '-mstack-protector-guard-reg=sp_el0' '-mstack-protector-guard-offset=1344' '-fno-common' '-fno-builtin' '-fno-stack-protector' '-ffixed-x18' '-D' 'DISABLE_BRANCH_PROFILING' '-D' 'BUILD_VDSO' '-O2' '-mcmodel=tiny' '-fasynchronous-unwind-tables' '-include' '/usr/local/google/home/briannorris/git/linux/lib/vdso/getrandom.c' '-D' 'KBUILD_MODFILE="arch/arm64/kernel/vdso/vgetrandom"' '-D' 'KBUILD_BASENAME="vgetrandom"' '-D' 'KBUILD_MODNAME="vgetrandom"' '-D' '__KBUILD_MODNAME=vgetrandom' '-c' '-o' 'arch/arm64/kernel/vdso/vgetrandom.o' '-v' '-dumpdir' 'arch/arm64/kernel/vdso/vgetrandom.'


> Does the intermediate source or assembler source have any
> ".cfi_section .sframe" statement?
> 
> $ make arch/arm64/kernel/vdso/vgetrandom.i

This fails to build with WERROR, because it seems to require the linker
step that fails, so I have to disable WERROR. Afterward:

$ grep -i sframe arch/arm64/kernel/vdso/vgetrandom.i
// (empty)

> $ make arch/arm64/kernel/vdso/vgetrandom.s

This fails to build.

$ make CROSS_COMPILE='ccache aarch64-linux-gnu-' ARCH=arm64 -j80 arch/arm64/kernel/vdso/vgetrandom.s
  CC      arch/arm64/kernel/vdso/vgetrandom.s
arch/arm64/kernel/vdso/vgetrandom.c:5:8: error: ‘__cvdso_getrandom’ undeclared here (not in a function)
    5 | typeof(__cvdso_getrandom) __kernel_getrandom;
      |        ^~~~~~~~~~~~~~~~~
arch/arm64/kernel/vdso/vgetrandom.c:7:1: error: unknown type name ‘ssize_t’
    7 | ssize_t __kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state, size_t opaque_len)
      | ^~~~~~~
arch/arm64/kernel/vdso/vgetrandom.c:7:42: error: unknown type name ‘size_t’
    7 | ssize_t __kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state, size_t opaque_len)
      |                                          ^~~~~~
arch/arm64/kernel/vdso/vgetrandom.c:4:1: note: ‘size_t’ is defined in header ‘<stddef.h>’; this is probably fixable by adding ‘#include <stddef.h>’
    3 | #include <uapi/asm-generic/errno.h>
  +++ |+#include <stddef.h>
    4 |
arch/arm64/kernel/vdso/vgetrandom.c:7:94: error: unknown type name ‘size_t’
    7 | ssize_t __kernel_getrandom(void *buffer, size_t len, unsigned int flags, void *opaque_state, size_t opaque_len)
      |                                                                                              ^~~~~~
arch/arm64/kernel/vdso/vgetrandom.c:7:94: note: ‘size_t’ is defined in header ‘<stddef.h>’; this is probably fixable by adding ‘#include <stddef.h>’
make[4]: *** [scripts/Makefile.build:184: arch/arm64/kernel/vdso/vgetrandom.s] Error 1
make[3]: *** [scripts/Makefile.build:549: arch/arm64/kernel] Error 2
make[2]: *** [scripts/Makefile.build:549: arch/arm64] Error 2

> Can you please verify that your arch/arm64/kernel/vdso/vgetrandom.o
> actually contains an .sframe section:
> 
> $ readelf -WS arch/arm64/kernel/vdso/vgetrandom.o

$ readelf -WS arch/arm64/kernel/vdso/vgetrandom.o | grep -i sframe
  [22] .sframe           GNU_SFRAME      0000000000000000 002438 000083 00   A  0   0  8
  [23] .rela.sframe      RELA            0000000000000000 003988 000018 18   I 24  22  8


Brian