diff options
Diffstat (limited to 'arch/arm64/kernel/syscall.c')
| -rw-r--r-- | arch/arm64/kernel/syscall.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c index 82098e6f6aa3..7ff2d7b9f517 100644 --- a/arch/arm64/kernel/syscall.c +++ b/arch/arm64/kernel/syscall.c @@ -8,8 +8,10 @@ #include <linux/syscalls.h> #include <asm/daifflags.h> +#include <asm/fpsimd.h> #include <asm/syscall.h> #include <asm/thread_info.h> +#include <asm/unistd.h> long compat_arm_syscall(struct pt_regs *regs); @@ -58,8 +60,8 @@ static inline bool has_syscall_work(unsigned long flags) int syscall_trace_enter(struct pt_regs *regs); void syscall_trace_exit(struct pt_regs *regs); -asmlinkage void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, - const syscall_fn_t syscall_table[]) +static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, + const syscall_fn_t syscall_table[]) { unsigned long flags = current_thread_info()->flags; @@ -96,3 +98,34 @@ asmlinkage void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, trace_exit: syscall_trace_exit(regs); } + +static inline void sve_user_discard(void) +{ + if (!system_supports_sve()) + return; + + clear_thread_flag(TIF_SVE); + + /* + * task_fpsimd_load() won't be called to update CPACR_EL1 in + * ret_to_user unless TIF_FOREIGN_FPSTATE is still set, which only + * happens if a context switch or kernel_neon_begin() or context + * modification (sigreturn, ptrace) intervenes. + * So, ensure that CPACR_EL1 is already correct for the fast-path case. + */ + sve_user_disable(); +} + +asmlinkage void el0_svc_handler(struct pt_regs *regs) +{ + sve_user_discard(); + el0_svc_common(regs, regs->regs[8], __NR_syscalls, sys_call_table); +} + +#ifdef CONFIG_COMPAT +asmlinkage void el0_svc_compat_handler(struct pt_regs *regs) +{ + el0_svc_common(regs, regs->regs[7], __NR_compat_syscalls, + compat_sys_call_table); +} +#endif |