diff options
Diffstat (limited to 'arch/arm64/kernel/suspend.c')
| -rw-r--r-- | arch/arm64/kernel/suspend.c | 53 |
1 files changed, 47 insertions, 6 deletions
diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c index c1dee9066ff9..eaaff94329cd 100644 --- a/arch/arm64/kernel/suspend.c +++ b/arch/arm64/kernel/suspend.c @@ -4,12 +4,16 @@ #include <linux/slab.h> #include <linux/uaccess.h> #include <linux/pgtable.h> +#include <linux/cpuidle.h> #include <asm/alternative.h> #include <asm/cacheflush.h> #include <asm/cpufeature.h> +#include <asm/cpuidle.h> #include <asm/daifflags.h> #include <asm/debug-monitors.h> #include <asm/exec.h> +#include <asm/fpsimd.h> +#include <asm/mte.h> #include <asm/memory.h> #include <asm/mmu_context.h> #include <asm/smp_plat.h> @@ -41,6 +45,8 @@ void notrace __cpu_suspend_exit(void) { unsigned int cpu = smp_processor_id(); + mte_suspend_exit(); + /* * We are resuming from reset with the idmap active in TTBR0_EL1. * We must uninstall the idmap and restore the expected MMU @@ -50,14 +56,15 @@ void notrace __cpu_suspend_exit(void) /* Restore CnP bit in TTBR1_EL1 */ if (system_supports_cnp()) - cpu_replace_ttbr1(lm_alias(swapper_pg_dir)); + cpu_enable_swapper_cnp(); /* * PSTATE was not saved over suspend/resume, re-enable any detected * features that might not have been set correctly. */ + if (alternative_has_cap_unlikely(ARM64_HAS_DIT)) + set_pstate_dit(1); __uaccess_enable_hw_pan(); - uao_thread_switch(current); /* * Restore HW breakpoint registers to sane values @@ -72,8 +79,12 @@ void notrace __cpu_suspend_exit(void) * have turned the mitigation on. If the user has forcefully * disabled it, make sure their wishes are obeyed. */ - if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) - arm64_set_ssbd_mitigation(false); + spectre_v4_enable_mitigation(NULL); + + sme_suspend_exit(); + + /* Restore additional feature-specific configuration */ + ptrauth_suspend_exit(); } /* @@ -88,21 +99,46 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) int ret = 0; unsigned long flags; struct sleep_stack_data state; + struct arm_cpuidle_irq_context context; + + /* + * Some portions of CPU state (e.g. PSTATE.{PAN,DIT}) are initialized + * before alternatives are patched, but are only restored by + * __cpu_suspend_exit() after alternatives are patched. To avoid + * accidentally losing these bits we must not attempt to suspend until + * after alternatives have been patched. + */ + WARN_ON(!system_capabilities_finalized()); + + /* Report any MTE async fault before going to suspend */ + mte_suspend_enter(); /* * From this point debug exceptions are disabled to prevent * updates to mdscr register (saved and restored along with * general purpose registers) from kernel debuggers. + * + * Strictly speaking the trace_hardirqs_off() here is superfluous, + * hardirqs should be firmly off by now. This really ought to use + * something like raw_local_daif_save(). */ flags = local_daif_save(); /* - * Function graph tracer state gets incosistent when the kernel + * Function graph tracer state gets inconsistent when the kernel * calls functions that never return (aka suspend finishers) hence * disable graph tracing during their execution. */ pause_graph_tracing(); + /* + * Switch to using DAIF.IF instead of PMR in order to reliably + * resume if we're using pseudo-NMIs. + */ + arm_cpuidle_save_irq_context(&context); + + ct_cpuidle_enter(); + if (__cpu_suspend_enter(&state)) { /* Call the suspend finisher */ ret = fn(arg); @@ -116,16 +152,21 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) */ if (!ret) ret = -EOPNOTSUPP; + + ct_cpuidle_exit(); } else { + ct_cpuidle_exit(); __cpu_suspend_exit(); } + arm_cpuidle_restore_irq_context(&context); + unpause_graph_tracing(); /* * Restore pstate flags. OS lock and mdscr have been already * restored, so from this point onwards, debugging is fully - * renabled if it was enabled when core started shutdown. + * reenabled if it was enabled when core started shutdown. */ local_daif_restore(flags); |