| Message ID | 20200507104049.47834-1-vincenzo.frascino@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: vdso: Add --eh-frame-hdr to ldflags | expand |
On Thu, 7 May 2020 11:40:49 +0100, Vincenzo Frascino wrote: > LLVM's unwinder depends on the .eh_frame_hdr being present for > unwinding. However, when compiling Linux with GCC, the section > is not present in the vdso library object and when compiling > with Clang, it is present, but it has zero length. > > With GCC the problem was not spotted because libgcc unwinder does > not require the .eh_frame_hdr section to be present. > > [...] Applied to arm64 (for-next/vdso), thanks! [1/1] arm64: vdso: Add --eh-frame-hdr to ldflags https://git.kernel.org/arm64/c/7e9f5e6629f6 Cheers,
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index 3862cad2410c..54008ec39e3a 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -18,7 +18,7 @@ targets := $(obj-vdso) vdso.so vdso.so.dbg obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) ldflags-y := -shared -nostdlib -soname=linux-vdso.so.1 --hash-style=sysv \ - --build-id -n -T + --eh-frame-hdr --build-id -n -T ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18 ccflags-y += -DDISABLE_BRANCH_PROFILING
LLVM's unwinder depends on the .eh_frame_hdr being present for unwinding. However, when compiling Linux with GCC, the section is not present in the vdso library object and when compiling with Clang, it is present, but it has zero length. With GCC the problem was not spotted because libgcc unwinder does not require the .eh_frame_hdr section to be present. Add --eh-frame-hdr to ldflags to correctly generate and populate the section for both GCC and LLVM. Fixes: 28b1a824a4f44 ("arm64: vdso: Substitute gettimeofday() with C implementation") Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Tamas Zsoldos <tamas.zsoldos@arm.com> Tested-by: Tamas Zsoldos <tamas.zsoldos@arm.com> Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> --- arch/arm64/kernel/vdso/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)