Patch "RISC-V: vdso: Do not add missing symbols to version section in linker script" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    RISC-V: vdso: Do not add missing symbols to version section in linker script

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     risc-v-vdso-do-not-add-missing-symbols-to-version-se.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 9585bb8208b22b5da772f30146cc3f4d7f9a73a9
Author: Nathan Chancellor <nathan@xxxxxxxxxx>
Date:   Tue Nov 8 10:13:23 2022 -0700

    RISC-V: vdso: Do not add missing symbols to version section in linker script
    
    [ Upstream commit fcae44fd36d052e956e69a64642fc03820968d78 ]
    
    Recently, ld.lld moved from '--undefined-version' to
    '--no-undefined-version' as the default, which breaks the compat vDSO
    build:
    
      ld.lld: error: version script assignment of 'LINUX_4.15' to symbol '__vdso_gettimeofday' failed: symbol not defined
      ld.lld: error: version script assignment of 'LINUX_4.15' to symbol '__vdso_clock_gettime' failed: symbol not defined
      ld.lld: error: version script assignment of 'LINUX_4.15' to symbol '__vdso_clock_getres' failed: symbol not defined
    
    These symbols are not present in the compat vDSO or the regular vDSO for
    32-bit but they are unconditionally included in the version section of
    the linker script, which is prohibited with '--no-undefined-version'.
    
    Fix this issue by only including the symbols that are actually exported
    in the version section of the linker script.
    
    Link: https://github.com/ClangBuiltLinux/linux/issues/1756
    Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
    Tested-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20221108171324.3377226-1-nathan@xxxxxxxxxx/
    Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index 84ac0fe612e7..db6548509bb3 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -28,6 +28,9 @@ obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
 
 obj-y += vdso.o
 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
+ifneq ($(filter vgettimeofday, $(vdso-syms)),)
+CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY
+endif
 
 # Disable -pg to prevent insert call site
 CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
diff --git a/arch/riscv/kernel/vdso/vdso.lds.S b/arch/riscv/kernel/vdso/vdso.lds.S
index e9111f700af0..3729cb28aac8 100644
--- a/arch/riscv/kernel/vdso/vdso.lds.S
+++ b/arch/riscv/kernel/vdso/vdso.lds.S
@@ -65,9 +65,11 @@ VERSION
 	LINUX_4.15 {
 	global:
 		__vdso_rt_sigreturn;
+#ifdef HAS_VGETTIMEOFDAY
 		__vdso_gettimeofday;
 		__vdso_clock_gettime;
 		__vdso_clock_getres;
+#endif
 		__vdso_getcpu;
 		__vdso_flush_icache;
 	local: *;