1140 		 * There is no need for RSB filling: entry_ibpb() ensures  in retbleed_select_mitigation()
1141 		 * all predictions, including the RSB, are invalidated,  in retbleed_select_mitigation()
1208 	[ITS_MITIGATION_RETPOLINE_STUFF]	= "Mitigation: Retpolines, Stuffing RSB",
1289 		pr_err("RSB stuff mitigation not supported, using default\n");  in its_select_mitigation()
1712 /* Disable in-kernel use of non-RSB RET predictors */
1734 	 * Similar to context switches, there are two types of RSB attacks  in spectre_v2_select_rsb_mitigation()
1737 	 * 1) RSB underflow  in spectre_v2_select_rsb_mitigation()
1739 	 * 2) Poisoned RSB entry  in spectre_v2_select_rsb_mitigation()
1742 	 * the RSB.  in spectre_v2_select_rsb_mitigation()
1745 	 * prediction isolation protections, RSB still needs to be cleared  in spectre_v2_select_rsb_mitigation()
1747 	 * user-space-poisoned RSB entries.  in spectre_v2_select_rsb_mitigation()
1749 	 * eIBRS should protect against RSB poisoning, but if the EIBRS_PBRSB  in spectre_v2_select_rsb_mitigation()
1750 	 * bug is present then a LITE version of RSB protection is required,  in spectre_v2_select_rsb_mitigation()
1769 		pr_info("Spectre v2 / SpectreRSB: Filling RSB on context switch and VMEXIT\n");  in spectre_v2_select_rsb_mitigation()
1775 		pr_warn_once("Unknown Spectre v2 mode, disabling RSB mitigation\n");  in spectre_v2_select_rsb_mitigation()
1952 	 * Disable alternate RSB predictions in kernel when indirect CALLs and  in spectre_v2_select_mitigation()
1954 	 * prediction from a non-RSB predictor is still a risk.  in spectre_v2_select_mitigation()
1968 	 * If Spectre v2 protection has been enabled, fill the RSB during a  in spectre_v2_select_mitigation()
1969 	 * context switch.  In general there are two types of RSB attacks  in spectre_v2_select_mitigation()
1972 	 * 1) RSB underflow  in spectre_v2_select_mitigation()
1974 	 *    Some Intel parts have "bottomless RSB".  When the RSB is empty,  in spectre_v2_select_mitigation()
1979 	 *    regardless of the state of the RSB.  in spectre_v2_select_mitigation()
1983 	 *    properties, so the RSB buffer filling wouldn't be necessary to  in spectre_v2_select_mitigation()
1986 	 *    The "user -> user" attack scenario is mitigated by RSB filling.  in spectre_v2_select_mitigation()
1988 	 * 2) Poisoned RSB entry  in spectre_v2_select_mitigation()
1991 	 *    'next' could be tricked into speculating with a user-poisoned RSB  in spectre_v2_select_mitigation()
1998 	 *    RSB clearing.  in spectre_v2_select_mitigation()
2000 	 * So to mitigate all cases, unconditionally fill RSB on context  in spectre_v2_select_mitigation()
2901 				 * There is no need for RSB filling: entry_ibpb() ensures  in srso_select_mitigation()
2902 				 * all predictions, including the RSB, are invalidated,  in srso_select_mitigation()
2920 				 * There is no need for RSB filling: entry_ibpb() ensures  in srso_select_mitigation()
2921 				 * all predictions, including the RSB, are invalidated,  in srso_select_mitigation()
3143 			  boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? "; RSB filling" : "",  in spectre_v2_show_state()