[tip: x86/core] x86: clean up symbol aliasing

From: tip-bot2 for Mark Rutland
Date: Wed Mar 09 2022 - 02:58:02 EST


The following commit has been merged into the x86/core branch of tip:

Commit-ID: 7be2e319640c8926bbba4e004a1bee9cf6ed67b0
Gitweb: https://git.kernel.org/tip/7be2e319640c8926bbba4e004a1bee9cf6ed67b0
Author: Mark Rutland <mark.rutland@xxxxxxx>
AuthorDate: Wed, 16 Feb 2022 16:22:28
Committer: Will Deacon <will@xxxxxxxxxx>
CommitterDate: Tue, 22 Feb 2022 16:21:34

x86: clean up symbol aliasing

Now that we have SYM_FUNC_ALIAS() and SYM_FUNC_ALIAS_WEAK(), use those
to simplify the definition of function aliases across arch/x86.

For clarity, where there are multiple annotations such as
EXPORT_SYMBOL(), I've tried to keep annotations grouped by symbol. For
example, where a function has a name and an alias which are both
exported, this is organised as:

SYM_FUNC_START(func)
... asm insns ...
SYM_FUNC_END(func)
EXPORT_SYMBOL(func)

SYM_FUNC_ALIAS(alias, func)
EXPORT_SYMBOL(alias)

Where there are only aliases and no exports or other annotations, I have
not bothered with line spacing, e.g.

SYM_FUNC_START(func)
... asm insns ...
SYM_FUNC_END(func)
SYM_FUNC_ALIAS(alias, func)

The tools/perf/ copies of memset_64.S and memset_64.S are updated
likewise to avoid the build system complaining these are mismatched:

| Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
| diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S
| Warning: Kernel ABI header at 'tools/arch/x86/lib/memset_64.S' differs from latest version at 'arch/x86/lib/memset_64.S'
| diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Acked-by: Mark Brown <broonie@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Slaby <jslaby@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220216162229.1076788-4-mark.rutland@xxxxxxx
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
---
arch/x86/boot/compressed/head_32.S | 3 +--
arch/x86/boot/compressed/head_64.S | 3 +--
arch/x86/crypto/aesni-intel_asm.S | 4 +---
arch/x86/lib/memcpy_64.S | 10 +++++-----
arch/x86/lib/memmove_64.S | 4 ++--
arch/x86/lib/memset_64.S | 6 +++---
tools/arch/x86/lib/memcpy_64.S | 10 +++++-----
tools/arch/x86/lib/memset_64.S | 6 +++---
8 files changed, 21 insertions(+), 25 deletions(-)

diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S
index 659fad5..3b354eb 100644
--- a/arch/x86/boot/compressed/head_32.S
+++ b/arch/x86/boot/compressed/head_32.S
@@ -152,14 +152,13 @@ SYM_FUNC_END(startup_32)

#ifdef CONFIG_EFI_STUB
SYM_FUNC_START(efi32_stub_entry)
-SYM_FUNC_START_ALIAS(efi_stub_entry)
add $0x4, %esp
movl 8(%esp), %esi /* save boot_params pointer */
call efi_main
/* efi_main returns the possibly relocated address of startup_32 */
jmp *%eax
SYM_FUNC_END(efi32_stub_entry)
-SYM_FUNC_END_ALIAS(efi_stub_entry)
+SYM_FUNC_ALIAS(efi_stub_entry, efi32_stub_entry)
#endif

.text
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index fd9441f..dea9530 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -535,7 +535,6 @@ SYM_CODE_END(startup_64)
#ifdef CONFIG_EFI_STUB
.org 0x390
SYM_FUNC_START(efi64_stub_entry)
-SYM_FUNC_START_ALIAS(efi_stub_entry)
and $~0xf, %rsp /* realign the stack */
movq %rdx, %rbx /* save boot_params pointer */
call efi_main
@@ -543,7 +542,7 @@ SYM_FUNC_START_ALIAS(efi_stub_entry)
leaq rva(startup_64)(%rax), %rax
jmp *%rax
SYM_FUNC_END(efi64_stub_entry)
-SYM_FUNC_END_ALIAS(efi_stub_entry)
+SYM_FUNC_ALIAS(efi_stub_entry, efi64_stub_entry)
#endif

.text
diff --git a/arch/x86/crypto/aesni-intel_asm.S b/arch/x86/crypto/aesni-intel_asm.S
index 363699d..837c1e0 100644
--- a/arch/x86/crypto/aesni-intel_asm.S
+++ b/arch/x86/crypto/aesni-intel_asm.S
@@ -1751,8 +1751,6 @@ SYM_FUNC_END(aesni_gcm_finalize)

#endif

-
-SYM_FUNC_START_LOCAL_ALIAS(_key_expansion_128)
SYM_FUNC_START_LOCAL(_key_expansion_256a)
pshufd $0b11111111, %xmm1, %xmm1
shufps $0b00010000, %xmm0, %xmm4
@@ -1764,7 +1762,7 @@ SYM_FUNC_START_LOCAL(_key_expansion_256a)
add $0x10, TKEYP
RET
SYM_FUNC_END(_key_expansion_256a)
-SYM_FUNC_END_ALIAS(_key_expansion_128)
+SYM_FUNC_ALIAS_LOCAL(_key_expansion_128, _key_expansion_256a)

SYM_FUNC_START_LOCAL(_key_expansion_192a)
pshufd $0b01010101, %xmm1, %xmm1
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S
index 59cf234..d0d7b9b 100644
--- a/arch/x86/lib/memcpy_64.S
+++ b/arch/x86/lib/memcpy_64.S
@@ -27,8 +27,7 @@
* Output:
* rax original destination
*/
-SYM_FUNC_START_ALIAS(__memcpy)
-SYM_FUNC_START_WEAK(memcpy)
+SYM_FUNC_START(__memcpy)
ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \
"jmp memcpy_erms", X86_FEATURE_ERMS

@@ -40,11 +39,12 @@ SYM_FUNC_START_WEAK(memcpy)
movl %edx, %ecx
rep movsb
RET
-SYM_FUNC_END(memcpy)
-SYM_FUNC_END_ALIAS(__memcpy)
-EXPORT_SYMBOL(memcpy)
+SYM_FUNC_END(__memcpy)
EXPORT_SYMBOL(__memcpy)

+SYM_FUNC_ALIAS_WEAK(memcpy, __memcpy)
+EXPORT_SYMBOL(memcpy)
+
/*
* memcpy_erms() - enhanced fast string memcpy. This is faster and
* simpler than memcpy. Use memcpy_erms when possible.
diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S
index 50ea390..d83cba3 100644
--- a/arch/x86/lib/memmove_64.S
+++ b/arch/x86/lib/memmove_64.S
@@ -24,7 +24,6 @@
* Output:
* rax: dest
*/
-SYM_FUNC_START_WEAK(memmove)
SYM_FUNC_START(__memmove)

mov %rdi, %rax
@@ -207,6 +206,7 @@ SYM_FUNC_START(__memmove)
13:
RET
SYM_FUNC_END(__memmove)
-SYM_FUNC_END_ALIAS(memmove)
EXPORT_SYMBOL(__memmove)
+
+SYM_FUNC_ALIAS_WEAK(memmove, __memmove)
EXPORT_SYMBOL(memmove)
diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S
index d624f2b..fc9ffd3 100644
--- a/arch/x86/lib/memset_64.S
+++ b/arch/x86/lib/memset_64.S
@@ -17,7 +17,6 @@
*
* rax original destination
*/
-SYM_FUNC_START_WEAK(memset)
SYM_FUNC_START(__memset)
/*
* Some CPUs support enhanced REP MOVSB/STOSB feature. It is recommended
@@ -42,10 +41,11 @@ SYM_FUNC_START(__memset)
movq %r9,%rax
RET
SYM_FUNC_END(__memset)
-SYM_FUNC_END_ALIAS(memset)
-EXPORT_SYMBOL(memset)
EXPORT_SYMBOL(__memset)

+SYM_FUNC_ALIAS_WEAK(memset, __memset)
+EXPORT_SYMBOL(memset)
+
/*
* ISO C memset - set a memory block to a byte value. This function uses
* enhanced rep stosb to override the fast string function.
diff --git a/tools/arch/x86/lib/memcpy_64.S b/tools/arch/x86/lib/memcpy_64.S
index 59cf234..d0d7b9b 100644
--- a/tools/arch/x86/lib/memcpy_64.S
+++ b/tools/arch/x86/lib/memcpy_64.S
@@ -27,8 +27,7 @@
* Output:
* rax original destination
*/
-SYM_FUNC_START_ALIAS(__memcpy)
-SYM_FUNC_START_WEAK(memcpy)
+SYM_FUNC_START(__memcpy)
ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \
"jmp memcpy_erms", X86_FEATURE_ERMS

@@ -40,11 +39,12 @@ SYM_FUNC_START_WEAK(memcpy)
movl %edx, %ecx
rep movsb
RET
-SYM_FUNC_END(memcpy)
-SYM_FUNC_END_ALIAS(__memcpy)
-EXPORT_SYMBOL(memcpy)
+SYM_FUNC_END(__memcpy)
EXPORT_SYMBOL(__memcpy)

+SYM_FUNC_ALIAS_WEAK(memcpy, __memcpy)
+EXPORT_SYMBOL(memcpy)
+
/*
* memcpy_erms() - enhanced fast string memcpy. This is faster and
* simpler than memcpy. Use memcpy_erms when possible.
diff --git a/tools/arch/x86/lib/memset_64.S b/tools/arch/x86/lib/memset_64.S
index d624f2b..fc9ffd3 100644
--- a/tools/arch/x86/lib/memset_64.S
+++ b/tools/arch/x86/lib/memset_64.S
@@ -17,7 +17,6 @@
*
* rax original destination
*/
-SYM_FUNC_START_WEAK(memset)
SYM_FUNC_START(__memset)
/*
* Some CPUs support enhanced REP MOVSB/STOSB feature. It is recommended
@@ -42,10 +41,11 @@ SYM_FUNC_START(__memset)
movq %r9,%rax
RET
SYM_FUNC_END(__memset)
-SYM_FUNC_END_ALIAS(memset)
-EXPORT_SYMBOL(memset)
EXPORT_SYMBOL(__memset)

+SYM_FUNC_ALIAS_WEAK(memset, __memset)
+EXPORT_SYMBOL(memset)
+
/*
* ISO C memset - set a memory block to a byte value. This function uses
* enhanced rep stosb to override the fast string function.