On 5/10/22 06:46, Nathan Chancellor wrote:
When linking vdso{32,64}.so.dbg with ld.lld, there is a warning about
not finding _start for the starting address:
ld.lld: warning: cannot find entry symbol _start; not setting start address
ld.lld: warning: cannot find entry symbol _start; not setting start address
Looking at GCC + GNU ld, the entry point address is 0x0:
$ llvm-readelf -h vdso{32,64}.so.dbg &| rg "(File|Entry point address):"
File: vdso32.so.dbg
Entry point address: 0x0
File: vdso64.so.dbg
Entry point address: 0x0
This matches what ld.lld emits:
$ powerpc64le-linux-gnu-readelf -p .comment vdso{32,64}.so.dbg
File: vdso32.so.dbg
String dump of section '.comment':
[ 0] Linker: LLD 14.0.0
[ 14] clang version 14.0.0 (Fedora 14.0.0-1.fc37)
File: vdso64.so.dbg
String dump of section '.comment':
[ 0] Linker: LLD 14.0.0
[ 14] clang version 14.0.0 (Fedora 14.0.0-1.fc37)
$ llvm-readelf -h vdso{32,64}.so.dbg &| rg "(File|Entry point address):"
File: vdso32.so.dbg
Entry point address: 0x0
File: vdso64.so.dbg
Entry point address: 0x0
Remove ENTRY to remove the warning, as it is unnecessary for the vDSO to
function correctly.
Sounds more like a bugfix to me - _start is simply not defined, I wonder
why ld is not complaining.
Tested-by: Alexey Kardashevskiy <a...@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <a...@ozlabs.ru>
Signed-off-by: Nathan Chancellor <nat...@kernel.org>
---
arch/powerpc/kernel/vdso/vdso32.lds.S | 1 -
arch/powerpc/kernel/vdso/vdso64.lds.S | 1 -
2 files changed, 2 deletions(-)
diff --git a/arch/powerpc/kernel/vdso/vdso32.lds.S
b/arch/powerpc/kernel/vdso/vdso32.lds.S
index 58e0099f70f4..e0d19d74455f 100644
--- a/arch/powerpc/kernel/vdso/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso/vdso32.lds.S
@@ -13,7 +13,6 @@ OUTPUT_FORMAT("elf32-powerpcle", "elf32-powerpcle",
"elf32-powerpcle")
OUTPUT_FORMAT("elf32-powerpc", "elf32-powerpc", "elf32-powerpc")
#endif
OUTPUT_ARCH(powerpc:common)
-ENTRY(_start)
SECTIONS
{
diff --git a/arch/powerpc/kernel/vdso/vdso64.lds.S
b/arch/powerpc/kernel/vdso/vdso64.lds.S
index 0288cad428b0..1a4a7bc4c815 100644
--- a/arch/powerpc/kernel/vdso/vdso64.lds.S
+++ b/arch/powerpc/kernel/vdso/vdso64.lds.S
@@ -13,7 +13,6 @@ OUTPUT_FORMAT("elf64-powerpcle", "elf64-powerpcle",
"elf64-powerpcle")
OUTPUT_FORMAT("elf64-powerpc", "elf64-powerpc", "elf64-powerpc")
#endif
OUTPUT_ARCH(powerpc:common64)
-ENTRY(_start)
SECTIONS
{
