[PATCH 5.2 071/135] riscv: Fix perf record without libelf support
From: Sasha Levin
Date: Thu Aug 22 2019 - 13:14:28 EST
From: Mao Han <han_mao@xxxxxxxxx>
[ Upstream commit b399abe7c21e248dc6224cadc9a378a2beb10cfd ]
This patch fix following perf record error by linking vdso.so with
build id.
perf.data perf.data.old
[ perf record: Woken up 1 times to write data ]
free(): double free detected in tcache 2
Aborted
perf record use filename__read_build_id(util/symbol-minimal.c) to get
build id when libelf is not supported. When vdso.so is linked without
build id, the section size of PT_NOTE will be zero, buf size will
realloc to zero and cause memory corruption.
Signed-off-by: Mao Han <han_mao@xxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxx>
Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
Signed-off-by: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/riscv/kernel/vdso/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index f1d6ffe43e428..49a5852fd07dd 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -37,7 +37,7 @@ $(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE
# these symbols in the kernel code rather than hand-coded addresses.
SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
- -Wl,--hash-style=both
+ -Wl,--build-id -Wl,--hash-style=both
$(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE
$(call if_changed,vdsold)
--
2.20.1