arm64: drop alignment from syscall tables (80d63bc3) · Commits · 戴 / test

Our syscall tables are aligned to 4096 bytes, which allowed their addresses to be generated with a single adrp in entry.S. This has the unfortunate property of wasting space in .rodata for the necessary padding. Now that the address is generated by C code, we can rely on the compiler to do the right thing, and drop the alignemnt. Signed-off-by:

Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by:

Will Deacon <will.deacon@arm.com>

arch/arm64/kernel/sys.c

+1 −5

Original line number	Diff line number	Diff line
		@@ -56,11 +56,7 @@ asmlinkage long sys_rt_sigreturn(void);
		#undef __SYSCALL
		#define __SYSCALL(nr, sym) [nr] = (syscall_fn_t)sym,

		/*
		* The sys_call_table array must be 4K aligned to be accessible from
		* kernel/entry.S.
		*/
		const syscall_fn_t sys_call_table[__NR_syscalls] __aligned(4096) = {
		const syscall_fn_t sys_call_table[__NR_syscalls] = {
		[0 ... __NR_syscalls - 1] = (syscall_fn_t)sys_ni_syscall,
		#include <asm/unistd.h>
		};

arch/arm64/kernel/sys32.c

+1 −5

Original line number	Diff line number	Diff line
		@@ -44,11 +44,7 @@ asmlinkage long compat_sys_mmap2_wrapper(void);
		#undef __SYSCALL
		#define __SYSCALL(nr, sym) [nr] = (syscall_fn_t)sym,

		/*
		* The sys_call_table array must be 4K aligned to be accessible from
		* kernel/entry.S.
		*/
		const syscall_fn_t compat_sys_call_table[__NR_compat_syscalls] __aligned(4096) = {
		const syscall_fn_t compat_sys_call_table[__NR_compat_syscalls] = {
		[0 ... __NR_compat_syscalls - 1] = (syscall_fn_t)sys_ni_syscall,
		#include <asm/unistd32.h>
		};

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