1131 		 * There is no need for RSB filling: entry_ibpb() ensures  in retbleed_select_mitigation()
1132 		 * all predictions, including the RSB, are invalidated,  in retbleed_select_mitigation()
1563 /* Disable in-kernel use of non-RSB RET predictors */
1585 	 * Similar to context switches, there are two types of RSB attacks  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1588 	 * 1) RSB underflow  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1590 	 * 2) Poisoned RSB entry  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1593 	 * the RSB.  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1596 	 * prediction isolation protections, RSB still needs to be cleared  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1598 	 * user-space-poisoned RSB entries.  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1600 	 * eIBRS should protect against RSB poisoning, but if the EIBRS_PBRSB  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1601 	 * bug is present then a LITE version of RSB protection is required,  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1621 		pr_info("Spectre v2 / SpectreRSB : Filling RSB on VMEXIT\n");  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1625 	pr_warn_once("Unknown Spectre v2 mode, disabling RSB mitigation at VM exit");  in spectre_v2_determine_rsb_fill_type_at_vmexit()
1805 	 * Disable alternate RSB predictions in kernel when indirect CALLs and  in spectre_v2_select_mitigation()
1807 	 * prediction from a non-RSB predictor is still a risk.  in spectre_v2_select_mitigation()
1821 	 * If Spectre v2 protection has been enabled, fill the RSB during a  in spectre_v2_select_mitigation()
1822 	 * context switch.  In general there are two types of RSB attacks  in spectre_v2_select_mitigation()
1825 	 * 1) RSB underflow  in spectre_v2_select_mitigation()
1827 	 *    Some Intel parts have "bottomless RSB".  When the RSB is empty,  in spectre_v2_select_mitigation()
1832 	 *    regardless of the state of the RSB.  in spectre_v2_select_mitigation()
1836 	 *    properties, so the RSB buffer filling wouldn't be necessary to  in spectre_v2_select_mitigation()
1839 	 *    The "user -> user" attack scenario is mitigated by RSB filling.  in spectre_v2_select_mitigation()
1841 	 * 2) Poisoned RSB entry  in spectre_v2_select_mitigation()
1844 	 *    'next' could be tricked into speculating with a user-poisoned RSB  in spectre_v2_select_mitigation()
1851 	 *    RSB clearing.  in spectre_v2_select_mitigation()
1853 	 * So to mitigate all cases, unconditionally fill RSB on context  in spectre_v2_select_mitigation()
1859 	pr_info("Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch\n");  in spectre_v2_select_mitigation()
2668 				 * There is no need for RSB filling: entry_ibpb() ensures  in srso_select_mitigation()
2669 				 * all predictions, including the RSB, are invalidated,  in srso_select_mitigation()
2879 			  boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? "; RSB filling" : "",  in spectre_v2_show_state()