[PATCH 4/7] x86/syscalls: stop filling syscall arrays with *_sys_ni_syscall

Masahiro Yamada masahiroy at kernel.org
Mon Mar 1 08:15:29 EST 2021


This is a follow-up cleanup after switching to the generic
syscalltbl.sh.

The old arch/x86/entry/syscalls/syscalltbl.sh skipped non-existing
syscalls. So, the generated syscalls_64.h, for example, had a big
hole in the syscall numbers 335-423 range. That is why there exists
[0 ... __NR_*_syscall_max] = &__*_sys_ni_cyscall.

The new script, scripts/syscalltbl.sh automatically fills holes
with __SYSCALL(<nr>, sys_ni_syscall), hence such ugly code can
go away. The designated initializers, '[nr] =' are also unneeded.

Also, there is no need to give __NR_*_syscall_max+1 because the array
size is implied by the number of syscalls in the generated headers.
Hence, there is no need to include <asm/unistd.h>, either.

Signed-off-by: Masahiro Yamada <masahiroy at kernel.org>
---

 arch/x86/entry/syscall_32.c     | 10 ++--------
 arch/x86/entry/syscall_64.c     | 10 ++--------
 arch/x86/entry/syscall_x32.c    | 10 ++--------
 arch/x86/um/sys_call_table_32.c |  6 ------
 arch/x86/um/sys_call_table_64.c |  6 ------
 5 files changed, 6 insertions(+), 36 deletions(-)

diff --git a/arch/x86/entry/syscall_32.c b/arch/x86/entry/syscall_32.c
index 70bf46e73b1c..8cfc9bc73e7f 100644
--- a/arch/x86/entry/syscall_32.c
+++ b/arch/x86/entry/syscall_32.c
@@ -5,7 +5,6 @@
 #include <linux/sys.h>
 #include <linux/cache.h>
 #include <linux/syscalls.h>
-#include <asm/unistd.h>
 #include <asm/syscall.h>
 
 #ifdef CONFIG_IA32_EMULATION
@@ -19,13 +18,8 @@
 #include <asm/syscalls_32.h>
 #undef __SYSCALL
 
-#define __SYSCALL(nr, sym) [nr] = __ia32_##sym,
+#define __SYSCALL(nr, sym) __ia32_##sym,
 
-__visible const sys_call_ptr_t ia32_sys_call_table[__NR_ia32_syscall_max+1] = {
-	/*
-	 * Smells like a compiler bug -- it doesn't work
-	 * when the & below is removed.
-	 */
-	[0 ... __NR_ia32_syscall_max] = &__ia32_sys_ni_syscall,
+__visible const sys_call_ptr_t ia32_sys_call_table[] = {
 #include <asm/syscalls_32.h>
 };
diff --git a/arch/x86/entry/syscall_64.c b/arch/x86/entry/syscall_64.c
index 82670bb10931..be120eec1fc9 100644
--- a/arch/x86/entry/syscall_64.c
+++ b/arch/x86/entry/syscall_64.c
@@ -5,20 +5,14 @@
 #include <linux/sys.h>
 #include <linux/cache.h>
 #include <linux/syscalls.h>
-#include <asm/unistd.h>
 #include <asm/syscall.h>
 
 #define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *);
 #include <asm/syscalls_64.h>
 #undef __SYSCALL
 
-#define __SYSCALL(nr, sym) [nr] = __x64_##sym,
+#define __SYSCALL(nr, sym) __x64_##sym,
 
-asmlinkage const sys_call_ptr_t sys_call_table[__NR_syscall_max+1] = {
-	/*
-	 * Smells like a compiler bug -- it doesn't work
-	 * when the & below is removed.
-	 */
-	[0 ... __NR_syscall_max] = &__x64_sys_ni_syscall,
+asmlinkage const sys_call_ptr_t sys_call_table[] = {
 #include <asm/syscalls_64.h>
 };
diff --git a/arch/x86/entry/syscall_x32.c b/arch/x86/entry/syscall_x32.c
index 6d2ef887d7b6..bdd0e03a1265 100644
--- a/arch/x86/entry/syscall_x32.c
+++ b/arch/x86/entry/syscall_x32.c
@@ -5,20 +5,14 @@
 #include <linux/sys.h>
 #include <linux/cache.h>
 #include <linux/syscalls.h>
-#include <asm/unistd.h>
 #include <asm/syscall.h>
 
 #define __SYSCALL(nr, sym) extern long __x64_##sym(const struct pt_regs *);
 #include <asm/syscalls_x32.h>
 #undef __SYSCALL
 
-#define __SYSCALL(nr, sym) [nr] = __x64_##sym,
+#define __SYSCALL(nr, sym) __x64_##sym,
 
-asmlinkage const sys_call_ptr_t x32_sys_call_table[__NR_x32_syscall_max+1] = {
-	/*
-	 * Smells like a compiler bug -- it doesn't work
-	 * when the & below is removed.
-	 */
-	[0 ... __NR_x32_syscall_max] = &__x64_sys_ni_syscall,
+asmlinkage const sys_call_ptr_t x32_sys_call_table[] = {
 #include <asm/syscalls_x32.h>
 };
diff --git a/arch/x86/um/sys_call_table_32.c b/arch/x86/um/sys_call_table_32.c
index e83619c365dc..f8323104e353 100644
--- a/arch/x86/um/sys_call_table_32.c
+++ b/arch/x86/um/sys_call_table_32.c
@@ -7,7 +7,6 @@
 #include <linux/linkage.h>
 #include <linux/sys.h>
 #include <linux/cache.h>
-#include <asm/unistd.h>
 #include <asm/syscall.h>
 
 #define __NO_STUBS
@@ -37,11 +36,6 @@
 extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
 
 const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = {
-	/*
-	 * Smells like a compiler bug -- it doesn't work
-	 * when the & below is removed.
-	 */
-	[0 ... __NR_syscall_max] = &sys_ni_syscall,
 #include <asm/syscalls_32.h>
 };
 
diff --git a/arch/x86/um/sys_call_table_64.c b/arch/x86/um/sys_call_table_64.c
index 6fb75af7cf54..5ed665dc785f 100644
--- a/arch/x86/um/sys_call_table_64.c
+++ b/arch/x86/um/sys_call_table_64.c
@@ -7,7 +7,6 @@
 #include <linux/linkage.h>
 #include <linux/sys.h>
 #include <linux/cache.h>
-#include <asm/unistd.h>
 #include <asm/syscall.h>
 
 #define __NO_STUBS
@@ -45,11 +44,6 @@
 extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
 
 const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = {
-	/*
-	 * Smells like a compiler bug -- it doesn't work
-	 * when the & below is removed.
-	 */
-	[0 ... __NR_syscall_max] = &sys_ni_syscall,
 #include <asm/syscalls_64.h>
 };
 
-- 
2.27.0




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