diff options
Diffstat (limited to 'arch/arm64/kernel/entry-common.c')
| -rw-r--r-- | arch/arm64/kernel/entry-common.c | 85 |
1 files changed, 72 insertions, 13 deletions
diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c index b77a15955f28..7c1970b341b8 100644 --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -103,7 +103,7 @@ static void noinstr exit_to_kernel_mode(struct pt_regs *regs) static __always_inline void __enter_from_user_mode(void) { lockdep_hardirqs_off(CALLER_ADDR0); - CT_WARN_ON(ct_state() != CONTEXT_USER); + CT_WARN_ON(ct_state() != CT_STATE_USER); user_exit_irqoff(); trace_hardirqs_off_finish(); mte_disable_tco_entry(current); @@ -132,7 +132,7 @@ static void do_notify_resume(struct pt_regs *regs, unsigned long thread_flags) do { local_irq_enable(); - if (thread_flags & _TIF_NEED_RESCHED) + if (thread_flags & (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)) schedule(); if (thread_flags & _TIF_UPROBE) @@ -393,20 +393,16 @@ static bool cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs) * As per the ABI exit SME streaming mode and clear the SVE state not * shared with FPSIMD on syscall entry. */ -static inline void fp_user_discard(void) +static inline void fpsimd_syscall_enter(void) { - /* - * If SME is active then exit streaming mode. If ZA is active - * then flush the SVE registers but leave userspace access to - * both SVE and SME enabled, otherwise disable SME for the - * task and fall through to disabling SVE too. This means - * that after a syscall we never have any streaming mode - * register state to track, if this changes the KVM code will - * need updating. - */ + /* Ensure PSTATE.SM is clear, but leave PSTATE.ZA as-is. */ if (system_supports_sme()) sme_smstop_sm(); + /* + * The CPU is not in streaming mode. If non-streaming SVE is not + * supported, there is no SVE state that needs to be discarded. + */ if (!system_supports_sve()) return; @@ -416,6 +412,33 @@ static inline void fp_user_discard(void) sve_vq_minus_one = sve_vq_from_vl(task_get_sve_vl(current)) - 1; sve_flush_live(true, sve_vq_minus_one); } + + /* + * Any live non-FPSIMD SVE state has been zeroed. Allow + * fpsimd_save_user_state() to lazily discard SVE state until either + * the live state is unbound or fpsimd_syscall_exit() is called. + */ + __this_cpu_write(fpsimd_last_state.to_save, FP_STATE_FPSIMD); +} + +static __always_inline void fpsimd_syscall_exit(void) +{ + if (!system_supports_sve()) + return; + + /* + * The current task's user FPSIMD/SVE/SME state is now bound to this + * CPU. The fpsimd_last_state.to_save value is either: + * + * - FP_STATE_FPSIMD, if the state has not been reloaded on this CPU + * since fpsimd_syscall_enter(). + * + * - FP_STATE_CURRENT, if the state has been reloaded on this CPU at + * any point. + * + * Reset this to FP_STATE_CURRENT to stop lazy discarding. + */ + __this_cpu_write(fpsimd_last_state.to_save, FP_STATE_CURRENT); } UNHANDLED(el1t, 64, sync) @@ -463,6 +486,24 @@ static void noinstr el1_bti(struct pt_regs *regs, unsigned long esr) exit_to_kernel_mode(regs); } +static void noinstr el1_gcs(struct pt_regs *regs, unsigned long esr) +{ + enter_from_kernel_mode(regs); + local_daif_inherit(regs); + do_el1_gcs(regs, esr); + local_daif_mask(); + exit_to_kernel_mode(regs); +} + +static void noinstr el1_mops(struct pt_regs *regs, unsigned long esr) +{ + enter_from_kernel_mode(regs); + local_daif_inherit(regs); + do_el1_mops(regs, esr); + local_daif_mask(); + exit_to_kernel_mode(regs); +} + static void noinstr el1_dbg(struct pt_regs *regs, unsigned long esr) { unsigned long far = read_sysreg(far_el1); @@ -505,6 +546,12 @@ asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs) case ESR_ELx_EC_BTI: el1_bti(regs, esr); break; + case ESR_ELx_EC_GCS: + el1_gcs(regs, esr); + break; + case ESR_ELx_EC_MOPS: + el1_mops(regs, esr); + break; case ESR_ELx_EC_BREAKPT_CUR: case ESR_ELx_EC_SOFTSTP_CUR: case ESR_ELx_EC_WATCHPT_CUR: @@ -684,6 +731,14 @@ static void noinstr el0_mops(struct pt_regs *regs, unsigned long esr) exit_to_user_mode(regs); } +static void noinstr el0_gcs(struct pt_regs *regs, unsigned long esr) +{ + enter_from_user_mode(regs); + local_daif_restore(DAIF_PROCCTX); + do_el0_gcs(regs, esr); + exit_to_user_mode(regs); +} + static void noinstr el0_inv(struct pt_regs *regs, unsigned long esr) { enter_from_user_mode(regs); @@ -707,10 +762,11 @@ static void noinstr el0_svc(struct pt_regs *regs) { enter_from_user_mode(regs); cortex_a76_erratum_1463225_svc_handler(); - fp_user_discard(); + fpsimd_syscall_enter(); local_daif_restore(DAIF_PROCCTX); do_el0_svc(regs); exit_to_user_mode(regs); + fpsimd_syscall_exit(); } static void noinstr el0_fpac(struct pt_regs *regs, unsigned long esr) @@ -766,6 +822,9 @@ asmlinkage void noinstr el0t_64_sync_handler(struct pt_regs *regs) case ESR_ELx_EC_MOPS: el0_mops(regs, esr); break; + case ESR_ELx_EC_GCS: + el0_gcs(regs, esr); + break; case ESR_ELx_EC_BREAKPT_LOW: case ESR_ELx_EC_SOFTSTP_LOW: case ESR_ELx_EC_WATCHPT_LOW: |