From 3085e1645e23888125224f66a710077cdb03106a Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Wed, 11 Jul 2018 14:56:41 +0100 Subject: arm64: remove sigreturn wrappers The arm64 sigreturn* syscall handlers are non-standard. Rather than taking a number of user parameters in registers as per the AAPCS, they expect the pt_regs as their sole argument. To make this work, we override the syscall definitions to invoke wrappers written in assembly, which mov the SP into x0, and branch to their respective C functions. On other architectures (such as x86), the sigreturn* functions take no argument and instead use current_pt_regs() to acquire the user registers. This requires less boilerplate code, and allows for other features such as interposing C code in this path. This patch takes the same approach for arm64. Signed-off-by: Mark Rutland Tentatively-reviewed-by: Dave Martin Reviewed-by: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon --- arch/arm64/kernel/sys.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/arm64/kernel/sys.c') diff --git a/arch/arm64/kernel/sys.c b/arch/arm64/kernel/sys.c index 72981bae10eb..31045f3fed92 100644 --- a/arch/arm64/kernel/sys.c +++ b/arch/arm64/kernel/sys.c @@ -48,8 +48,7 @@ SYSCALL_DEFINE1(arm64_personality, unsigned int, personality) /* * Wrappers to pass the pt_regs argument. */ -asmlinkage long sys_rt_sigreturn_wrapper(void); -#define sys_rt_sigreturn sys_rt_sigreturn_wrapper +asmlinkage long sys_rt_sigreturn(void); #define sys_personality sys_arm64_personality #undef __SYSCALL -- cgit v1.2.3