diff options
| -rw-r--r-- | arch/arm64/include/asm/syscall.h | 4 | ||||
| -rw-r--r-- | arch/arm64/kernel/entry.S | 42 | ||||
| -rw-r--r-- | arch/arm64/kernel/syscall.c | 37 |
3 files changed, 43 insertions, 40 deletions
diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h index 50841cb1bfa9..b83d0e6980a3 100644 --- a/arch/arm64/include/asm/syscall.h +++ b/arch/arm64/include/asm/syscall.h @@ -26,6 +26,10 @@ typedef long (*syscall_fn_t)(unsigned long, unsigned long, extern const syscall_fn_t sys_call_table[]; +#ifdef CONFIG_COMPAT +extern const syscall_fn_t compat_sys_call_table[]; +#endif + static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) { diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 05b9f03f3e00..156c4e3fd1a4 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -720,14 +720,9 @@ el0_sync_compat: b.ge el0_dbg b el0_inv el0_svc_compat: - /* - * AArch32 syscall handling - */ - ldr x16, [tsk, #TSK_TI_FLAGS] // load thread flags - adrp stbl, compat_sys_call_table // load compat syscall table pointer - mov wscno, w7 // syscall number in w7 (r7) - mov wsc_nr, #__NR_compat_syscalls - b el0_svc_naked + mov x0, sp + bl el0_svc_compat_handler + b ret_to_user .align 6 el0_irq_compat: @@ -925,37 +920,8 @@ ENDPROC(ret_to_user) */ .align 6 el0_svc: - ldr x16, [tsk, #TSK_TI_FLAGS] // load thread flags - adrp stbl, sys_call_table // load syscall table pointer - mov wscno, w8 // syscall number in w8 - mov wsc_nr, #__NR_syscalls - -#ifdef CONFIG_ARM64_SVE -alternative_if_not ARM64_SVE - b el0_svc_naked -alternative_else_nop_endif - tbz x16, #TIF_SVE, el0_svc_naked // Skip unless TIF_SVE set: - bic x16, x16, #_TIF_SVE // discard SVE state - str x16, [tsk, #TSK_TI_FLAGS] - - /* - * 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: - */ - mrs x9, cpacr_el1 - bic x9, x9, #CPACR_EL1_ZEN_EL0EN // disable SVE for el0 - msr cpacr_el1, x9 // synchronised by eret to el0 -#endif - -el0_svc_naked: // compat entry point mov x0, sp - mov w1, wscno - mov w2, wsc_nr - mov x3, stbl - bl el0_svc_common + bl el0_svc_handler b ret_to_user ENDPROC(el0_svc) 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 |