zenbleed/000775 000177 000177 00000000000 14457611706 012303 5ustar00mrgmrg000000 000000 zenbleed/Makefile000644 000177 000177 00000000143 14457620613 013734 0ustar00mrgmrg000000 000000 # $NetBSD$ .include "../Makefile.inc" KMOD= zenbleed SRCS= zenbleed.c .include zenbleed/zenbleed.c000644 000177 000177 00000006123 14460154156 014232 0ustar00mrgmrg000000 000000 /* * Copyright (c) 2023 Matthew R. Green * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * stupid module that will set bit 9 in the DE_CFG register when loaded, and * unset if it wasn't set upon unload. skips cpus that report being non-SMT * ID 0. */ #include #include #include #include #include #include MODULE(MODULE_CLASS_MISC, zenbleed, NULL); #define DE_CFG_ERRATA_ZENBLEED __BIT(9) static bool orig[MAXCPUS]; static void zenbleed_checkset(void *v1, void *v2) { uint64_t val; unsigned num = cpu_number(); if (curcpu()->ci_data.cpu_smt_id != 0) return; val = rdmsr_locked(MSR_DE_CFG); if ((val & DE_CFG_ERRATA_ZENBLEED) == 0) { wrmsr_locked(MSR_DE_CFG, val | DE_CFG_ERRATA_ZENBLEED); printf("%s: cpu%d set DE_CFG_ERRATA_ZENBLEED bit\n", __func__, num); } else { printf("%s: cpu%d DE_CFG_ERRATA_ZENBLEED bit already set\n", __func__, num); orig[num] = true; } } static void zenbleed_checkunset(void *v1, void *v2) { uint64_t val; unsigned num = cpu_number(); if (curcpu()->ci_data.cpu_smt_id != 0) return; val = rdmsr_locked(MSR_DE_CFG); if ((val & DE_CFG_ERRATA_ZENBLEED) != 0) { if (orig[num]) { printf("%s: cpu%d left DE_CFG_ERRATA_ZENBLEED bit enabled (as at modload)\n", __func__, num); } else { val &= ~DE_CFG_ERRATA_ZENBLEED; wrmsr_locked(MSR_DE_CFG, val); printf("%s: cpu%d unset DE_CFG_ERRATA_ZENBLEED bit\n", __func__, num); } } else { printf("%s: cpu%d DE_CFG_ERRATA_ZENBLEED bit already not set\n", __func__, num); } } static int zenbleed_modcmd(modcmd_t cmd, void *arg) { uint64_t w; switch (cmd) { case MODULE_CMD_INIT: w = xc_broadcast(0, zenbleed_checkset, 0, 0); xc_wait(w); return 0; case MODULE_CMD_FINI: w = xc_broadcast(0, zenbleed_checkunset, 0, 0); xc_wait(w); return 0; default: return ENOTTY; } }