diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2018-07-11 14:56:41 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2018-07-12 14:40:39 +0100 |
| commit | 3085e1645e23888125224f66a710077cdb03106a (patch) | |
| tree | a0aa48b29c26aa10c8d7e07fb0a5da7edac7b28b /arch/arm64/kernel/sys.c | |
| parent | f9209e26293300db80a57a6bf2f71ccb26ad45db (diff) | |
| download | linux-3085e1645e23888125224f66a710077cdb03106a.tar.bz2 | |
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 <mark.rutland@arm.com>
Tentatively-reviewed-by: Dave Martin <dave.martin@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/kernel/sys.c')
| -rw-r--r-- | arch/arm64/kernel/sys.c | 3 |
1 files changed, 1 insertions, 2 deletions
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 |