3  * Handle detection, reporting and mitigation of Spectre v1, v2, v3a and v4, as
36  * We try to ensure that the mitigation state can never change as the result of
64 	return sprintf(buf, "Mitigation: __user pointer sanitization\n");  in cpu_show_spectre_v1()
97 		pr_info_once("spectre-v2 mitigation disabled by command line option\n");  in spectre_v2_mitigations_off()
146 		return sprintf(buf, "Mitigation: %s%s\n", v2_str, bhb_str);  in cpu_show_spectre_v2()
298 	 * still rely on firmware for the mitigation at EL2.  in spectre_v2_enable_fw_mitigation()
357  * A major source of headaches is that the software mitigation is enabled both
364  * all of the currently onlined CPUs are safelisted, as the mitigation tends to
367  * The only good part is that if the firmware mitigation is present, then it is
369  * vulnerable CPU if one of the boot CPUs is using the firmware mitigation.
418  * Wrap these up in some helpers, which prefer disabling the mitigation if faced
419  * with contradictory parameters. The mitigation is always either "off",
428 		pr_info_once("spectre-v4 mitigation disabled by command-line option\n");  in spectre_v4_mitigations_off()
433 /* Do we need to toggle the mitigation state on entry to/exit from the kernel? */
453 		return sprintf(buf, "Mitigation: Speculative Store Bypass disabled via prctl\n");  in cpu_show_spec_store_bypass()
577  * Patch a branch over the Spectre-v4 mitigation code with a NOP so that
597  * Patch a NOP in the Spectre-v4 mitigation code with an SMC/HVC instruction
598  * to call into firmware to adjust the mitigation state.
680  * The Spectre-v4 mitigation can be controlled via a prctl() from userspace.
704 		/* Enable speculation: disable mitigation */  in ssbd_prctl_set()
713 		 * If the mitigation is forced on, then speculation is forced  in ssbd_prctl_set()
722 		/* Force disable speculation: force enable mitigation */  in ssbd_prctl_set()
724 		 * If the mitigation is forced off, then speculation is forced  in ssbd_prctl_set()
733 		/* Disable speculation: enable mitigation */  in ssbd_prctl_set()
741 		/* Disable speculation until execve(): enable mitigation */  in ssbd_prctl_set()
743 		 * If the mitigation state is forced one way or the other, then  in ssbd_prctl_set()
794 	/* Check the mitigation state for this task */  in ssbd_prctl_get()
824  * - Has the ClearBHB instruction to perform the mitigation.
826  *   software mitigation in the vectors is needed.
1014 		pr_info_once("spectre-bhb mitigation disabled by compile time option\n");  in spectre_bhb_enable_mitigation()
1016 		pr_info_once("spectre-bhb mitigation disabled by command line option\n");  in spectre_bhb_enable_mitigation()