From: Hans-Jörg Höxer Subject: Re: AMD SEV: confidential autoconf whitelist To: Date: Tue, 9 Sep 2025 11:42:38 +0200 Hi, this is an updated diff that works well on vmd/vmm and linux/kvm hosts with SEV-ES enabled guests. The previous discussion raised some questions, thanks for your input! All in all we came to the conclusion to proceed with this approach. ok? Take care, HJ. ------------------------------------------------------------------------- commit 576036aa72fef155f1584690fab5bdfe018672b8 Author: Hans-Joerg Hoexer Date: Sat Aug 2 12:58:50 2025 +0200 Whitelist devices in cfdrive for use when SEV is enabled Skip devices, that are not flagged for use with SEV. Hook into config_search() and isascan(). diff --git a/sys/arch/amd64/amd64/bios.c b/sys/arch/amd64/amd64/bios.c index 3a264d09d5b..15dec870ba6 100644 --- a/sys/arch/amd64/amd64/bios.c +++ b/sys/arch/amd64/amd64/bios.c @@ -50,7 +50,7 @@ const struct cfattach bios_ca = { }; struct cfdriver bios_cd = { - NULL, "bios", DV_DULL + NULL, "bios", DV_DULL, CD_COCOVM }; struct smbios_entry smbios_entry; diff --git a/sys/arch/amd64/amd64/cpu.c b/sys/arch/amd64/amd64/cpu.c index 1287c610344..b8ad479cefa 100644 --- a/sys/arch/amd64/amd64/cpu.c +++ b/sys/arch/amd64/amd64/cpu.c @@ -445,7 +445,7 @@ const struct cfattach cpu_ca = { }; struct cfdriver cpu_cd = { - NULL, "cpu", DV_DULL + NULL, "cpu", DV_DULL, CD_COCOVM }; /* diff --git a/sys/arch/amd64/amd64/ioapic.c b/sys/arch/amd64/amd64/ioapic.c index 9989fdfeb29..40af6c4154d 100644 --- a/sys/arch/amd64/amd64/ioapic.c +++ b/sys/arch/amd64/amd64/ioapic.c @@ -231,7 +231,7 @@ const struct cfattach ioapic_ca = { }; struct cfdriver ioapic_cd = { - NULL, "ioapic", DV_DULL + NULL, "ioapic", DV_DULL, CD_COCOVM }; int diff --git a/sys/arch/amd64/amd64/machdep.c b/sys/arch/amd64/amd64/machdep.c index 3462ac54559..7c540328d98 100644 --- a/sys/arch/amd64/amd64/machdep.c +++ b/sys/arch/amd64/amd64/machdep.c @@ -1474,6 +1474,8 @@ init_x86_64(paddr_t first_avail) cpu_init_early_vctrap(first_avail); first_avail += 2 * NBPG; } + if (ISSET(cpu_sev_guestmode, SEV_STAT_ENABLED)) + boothowto |= RB_COCOVM; /* * locore0 mapped 3 pages for use before the pmap is initialized diff --git a/sys/arch/amd64/amd64/mainbus.c b/sys/arch/amd64/amd64/mainbus.c index 030f0b1212f..f77a67f5517 100644 --- a/sys/arch/amd64/amd64/mainbus.c +++ b/sys/arch/amd64/amd64/mainbus.c @@ -83,7 +83,7 @@ const struct cfattach mainbus_ca = { }; struct cfdriver mainbus_cd = { - NULL, "mainbus", DV_DULL + NULL, "mainbus", DV_DULL, CD_COCOVM }; int mainbus_print(void *, const char *); diff --git a/sys/arch/amd64/pci/acpipci.c b/sys/arch/amd64/pci/acpipci.c index 5b07e2d3aba..81d8ad3ced0 100644 --- a/sys/arch/amd64/pci/acpipci.c +++ b/sys/arch/amd64/pci/acpipci.c @@ -76,7 +76,7 @@ const struct cfattach acpipci_ca = { }; struct cfdriver acpipci_cd = { - NULL, "acpipci", DV_DULL + NULL, "acpipci", DV_DULL, CD_COCOVM }; const char *acpipci_hids[] = { diff --git a/sys/arch/amd64/pci/pchb.c b/sys/arch/amd64/pci/pchb.c index 9b10011e2db..eb06df06b19 100644 --- a/sys/arch/amd64/pci/pchb.c +++ b/sys/arch/amd64/pci/pchb.c @@ -122,7 +122,7 @@ const struct cfattach pchb_ca = { }; struct cfdriver pchb_cd = { - NULL, "pchb", DV_DULL + NULL, "pchb", DV_DULL, CD_COCOVM }; int pchb_print(void *, const char *); diff --git a/sys/dev/acpi/acpi.c b/sys/dev/acpi/acpi.c index 7bcf56cab49..bb3645528c9 100644 --- a/sys/dev/acpi/acpi.c +++ b/sys/dev/acpi/acpi.c @@ -184,7 +184,7 @@ struct acpi_softc *acpi_softc; extern struct aml_node aml_root; struct cfdriver acpi_cd = { - NULL, "acpi", DV_DULL + NULL, "acpi", DV_DULL, CD_COCOVM }; uint8_t diff --git a/sys/dev/acpi/acpicmos.c b/sys/dev/acpi/acpicmos.c index 6e424e26530..068787c1922 100644 --- a/sys/dev/acpi/acpicmos.c +++ b/sys/dev/acpi/acpicmos.c @@ -37,7 +37,7 @@ const struct cfattach acpicmos_ca = { }; struct cfdriver acpicmos_cd = { - NULL, "acpicmos", DV_DULL + NULL, "acpicmos", DV_DULL, CD_COCOVM }; const char *acpicmos_hids[] = { diff --git a/sys/dev/acpi/acpicpu_x86.c b/sys/dev/acpi/acpicpu_x86.c index 15f0ceeaeae..a5ddc55b1b3 100644 --- a/sys/dev/acpi/acpicpu_x86.c +++ b/sys/dev/acpi/acpicpu_x86.c @@ -183,7 +183,7 @@ const struct cfattach acpicpu_ca = { }; struct cfdriver acpicpu_cd = { - NULL, "acpicpu", DV_DULL + NULL, "acpicpu", DV_DULL, CD_COCOVM }; const char *acpicpu_hids[] = { diff --git a/sys/dev/acpi/acpihpet.c b/sys/dev/acpi/acpihpet.c index dd992132678..dd25309c1c5 100644 --- a/sys/dev/acpi/acpihpet.c +++ b/sys/dev/acpi/acpihpet.c @@ -79,7 +79,7 @@ const struct cfattach acpihpet_ca = { }; struct cfdriver acpihpet_cd = { - NULL, "acpihpet", DV_DULL + NULL, "acpihpet", DV_DULL, CD_COCOVM }; uint64_t diff --git a/sys/dev/acpi/acpimadt.c b/sys/dev/acpi/acpimadt.c index 3faed32b355..6359ffd925b 100644 --- a/sys/dev/acpi/acpimadt.c +++ b/sys/dev/acpi/acpimadt.c @@ -48,7 +48,7 @@ const struct cfattach acpimadt_ca = { }; struct cfdriver acpimadt_cd = { - NULL, "acpimadt", DV_DULL + NULL, "acpimadt", DV_DULL, CD_COCOVM }; int acpimadt_validate(struct acpi_madt *); diff --git a/sys/dev/acpi/acpimcfg.c b/sys/dev/acpi/acpimcfg.c index f3e520882aa..b7df8a297a0 100644 --- a/sys/dev/acpi/acpimcfg.c +++ b/sys/dev/acpi/acpimcfg.c @@ -31,7 +31,7 @@ const struct cfattach acpimcfg_ca = { }; struct cfdriver acpimcfg_cd = { - NULL, "acpimcfg", DV_DULL + NULL, "acpimcfg", DV_DULL, CD_COCOVM }; int diff --git a/sys/dev/acpi/acpiprt.c b/sys/dev/acpi/acpiprt.c index 39de79dcfca..1011ec68600 100644 --- a/sys/dev/acpi/acpiprt.c +++ b/sys/dev/acpi/acpiprt.c @@ -77,7 +77,7 @@ const struct cfattach acpiprt_ca = { }; struct cfdriver acpiprt_cd = { - NULL, "acpiprt", DV_DULL + NULL, "acpiprt", DV_DULL, CD_COCOVM }; void acpiprt_prt_add(struct acpiprt_softc *, struct aml_value *); diff --git a/sys/dev/acpi/acpitimer.c b/sys/dev/acpi/acpitimer.c index 11a8b9eccf3..498146a592e 100644 --- a/sys/dev/acpi/acpitimer.c +++ b/sys/dev/acpi/acpitimer.c @@ -55,7 +55,7 @@ const struct cfattach acpitimer_ca = { }; struct cfdriver acpitimer_cd = { - NULL, "acpitimer", DV_DULL + NULL, "acpitimer", DV_DULL, CD_COCOVM }; int diff --git a/sys/dev/efi/efi.c b/sys/dev/efi/efi.c index 43a774253fa..e600a3b1e47 100644 --- a/sys/dev/efi/efi.c +++ b/sys/dev/efi/efi.c @@ -24,7 +24,7 @@ #include struct cfdriver efi_cd = { - NULL, "efi", DV_DULL + NULL, "efi", DV_DULL, CD_COCOVM }; int efiioc_get_table(struct efi_softc *sc, void *); diff --git a/sys/dev/ic/com.c b/sys/dev/ic/com.c index dd45e3c901c..da29f82243b 100644 --- a/sys/dev/ic/com.c +++ b/sys/dev/ic/com.c @@ -96,7 +96,7 @@ void compwroff(struct com_softc *); void cominit(bus_space_tag_t, bus_space_handle_t, int, int); struct cfdriver com_cd = { - NULL, "com", DV_TTY + NULL, "com", DV_TTY, CD_COCOVM }; int comdefaultrate = TTYDEF_SPEED; diff --git a/sys/dev/isa/isa.c b/sys/dev/isa/isa.c index 2d11dc33a84..2a799f8a82a 100644 --- a/sys/dev/isa/isa.c +++ b/sys/dev/isa/isa.c @@ -62,6 +62,7 @@ #include #include #include +#include #include #include @@ -84,7 +85,7 @@ const struct cfattach isa_ca = { }; struct cfdriver isa_cd = { - NULL, "isa", DV_DULL, CD_INDIRECT + NULL, "isa", DV_DULL, CD_INDIRECT | CD_COCOVM }; int @@ -218,6 +219,10 @@ isascan(struct device *parent, void *match) ia.ipa_ndrq = 2; ia.ia_delaybah = sc->sc_delaybah; + if (ISSET(boothowto, RB_COCOVM) && + !ISSET(cf->cf_driver->cd_mode, CD_COCOVM)) + return; + if (cf->cf_fstate == FSTATE_STAR) { struct isa_attach_args ia2 = ia; diff --git a/sys/dev/pci/pci.c b/sys/dev/pci/pci.c index c0376842914..d7601dd976e 100644 --- a/sys/dev/pci/pci.c +++ b/sys/dev/pci/pci.c @@ -90,7 +90,7 @@ const struct cfattach pci_ca = { }; struct cfdriver pci_cd = { - NULL, "pci", DV_DULL + NULL, "pci", DV_DULL, CD_COCOVM }; int pci_ndomains; diff --git a/sys/dev/pci/ppb.c b/sys/dev/pci/ppb.c index cf7cb120cc1..f6ab05f9168 100644 --- a/sys/dev/pci/ppb.c +++ b/sys/dev/pci/ppb.c @@ -113,7 +113,7 @@ const struct cfattach ppb_ca = { }; struct cfdriver ppb_cd = { - NULL, "ppb", DV_DULL + NULL, "ppb", DV_DULL, CD_COCOVM }; void ppb_alloc_busrange(struct ppb_softc *, struct pci_attach_args *, diff --git a/sys/dev/pv/if_vio.c b/sys/dev/pv/if_vio.c index a94945a8ea0..458f98c6a7a 100644 --- a/sys/dev/pv/if_vio.c +++ b/sys/dev/pv/if_vio.c @@ -382,7 +382,7 @@ const struct cfattach vio_ca = { }; struct cfdriver vio_cd = { - NULL, "vio", DV_IFNET + NULL, "vio", DV_IFNET, CD_COCOVM }; int diff --git a/sys/dev/pv/pvbus.c b/sys/dev/pv/pvbus.c index 165fcc9fbff..a482072de4b 100644 --- a/sys/dev/pv/pvbus.c +++ b/sys/dev/pv/pvbus.c @@ -68,7 +68,8 @@ const struct cfattach pvbus_ca = { struct cfdriver pvbus_cd = { NULL, "pvbus", - DV_DULL + DV_DULL, + CD_COCOVM }; struct pvbus_type { diff --git a/sys/dev/pv/pvclock.c b/sys/dev/pv/pvclock.c index 89eff0ce248..fd69960ddda 100644 --- a/sys/dev/pv/pvclock.c +++ b/sys/dev/pv/pvclock.c @@ -125,7 +125,8 @@ const struct cfattach pvclock_ca = { struct cfdriver pvclock_cd = { NULL, "pvclock", - DV_DULL + DV_DULL, + CD_COCOVM }; struct timecounter pvclock_timecounter = { diff --git a/sys/dev/pv/vioblk.c b/sys/dev/pv/vioblk.c index 7f7a518332f..761ce73a847 100644 --- a/sys/dev/pv/vioblk.c +++ b/sys/dev/pv/vioblk.c @@ -146,7 +146,7 @@ const struct cfattach vioblk_ca = { }; struct cfdriver vioblk_cd = { - NULL, "vioblk", DV_DULL + NULL, "vioblk", DV_DULL, CD_COCOVM }; const struct scsi_adapter vioblk_switch = { diff --git a/sys/dev/pv/viocon.c b/sys/dev/pv/viocon.c index 95a1e875579..1d24074c54d 100644 --- a/sys/dev/pv/viocon.c +++ b/sys/dev/pv/viocon.c @@ -144,7 +144,7 @@ const struct cfattach viocon_ca = { }; struct cfdriver viocon_cd = { - NULL, "viocon", DV_TTY + NULL, "viocon", DV_TTY, CD_COCOVM }; static inline struct viocon_softc * diff --git a/sys/dev/pv/viornd.c b/sys/dev/pv/viornd.c index 484f7ce1be0..9eeb6115f3e 100644 --- a/sys/dev/pv/viornd.c +++ b/sys/dev/pv/viornd.c @@ -66,7 +66,7 @@ const struct cfattach viornd_ca = { }; struct cfdriver viornd_cd = { - NULL, "viornd", DV_DULL + NULL, "viornd", DV_DULL, CD_COCOVM }; int diff --git a/sys/dev/pv/virtio.c b/sys/dev/pv/virtio.c index ac0432dc9f9..4a8d140f797 100644 --- a/sys/dev/pv/virtio.c +++ b/sys/dev/pv/virtio.c @@ -48,7 +48,7 @@ void vq_free_entry(struct virtqueue *, struct vq_entry *); struct vq_entry *vq_alloc_entry(struct virtqueue *); struct cfdriver virtio_cd = { - NULL, "virtio", DV_DULL + NULL, "virtio", DV_DULL, CD_COCOVM }; static const char * const virtio_device_name[] = { diff --git a/sys/dev/pv/vmmci.c b/sys/dev/pv/vmmci.c index 984626393cd..18930c62766 100644 --- a/sys/dev/pv/vmmci.c +++ b/sys/dev/pv/vmmci.c @@ -72,7 +72,7 @@ const struct cfattach vmmci_ca = { #define VMMCI_F_SYNCRTC (1ULL<<2) struct cfdriver vmmci_cd = { - NULL, "vmmci", DV_DULL + NULL, "vmmci", DV_DULL, CD_COCOVM }; int diff --git a/sys/dev/softraid.c b/sys/dev/softraid.c index c10ebeaaa93..41929692397 100644 --- a/sys/dev/softraid.c +++ b/sys/dev/softraid.c @@ -88,7 +88,7 @@ const struct cfattach softraid_ca = { }; struct cfdriver softraid_cd = { - NULL, "softraid", DV_DULL + NULL, "softraid", DV_DULL, CD_COCOVM }; /* scsi & discipline */ diff --git a/sys/dev/vscsi.c b/sys/dev/vscsi.c index 31885a6b9c9..2e2deb25b1f 100644 --- a/sys/dev/vscsi.c +++ b/sys/dev/vscsi.c @@ -89,7 +89,8 @@ const struct cfattach vscsi_ca = { struct cfdriver vscsi_cd = { NULL, "vscsi", - DV_DULL + DV_DULL, + CD_COCOVM }; void vscsi_cmd(struct scsi_xfer *); diff --git a/sys/kern/subr_autoconf.c b/sys/kern/subr_autoconf.c index 41633140dc6..eec9eef15ce 100644 --- a/sys/kern/subr_autoconf.c +++ b/sys/kern/subr_autoconf.c @@ -216,6 +216,9 @@ config_search(cfmatch_t fn, struct device *parent, void *aux) if (cf->cf_driver->cd_class == DV_TAPE) continue; } + if (ISSET(boothowto, RB_COCOVM) && + !ISSET(cf->cf_driver->cd_mode, CD_COCOVM)) + continue; for (p = cf->cf_parents; *p >= 0; p++) if (parent->dv_cfdata == &cfdata[*p]) mapply(&m, cf); diff --git a/sys/scsi/mpath.c b/sys/scsi/mpath.c index c94a4ff5cf7..090c78c35f1 100644 --- a/sys/scsi/mpath.c +++ b/sys/scsi/mpath.c @@ -79,7 +79,8 @@ const struct cfattach mpath_ca = { struct cfdriver mpath_cd = { NULL, "mpath", - DV_DULL + DV_DULL, + CD_COCOVM }; void mpath_cmd(struct scsi_xfer *); diff --git a/sys/scsi/scsiconf.c b/sys/scsi/scsiconf.c index 495020a23a3..2f9ab1b15d0 100644 --- a/sys/scsi/scsiconf.c +++ b/sys/scsi/scsiconf.c @@ -102,7 +102,7 @@ const struct cfattach scsibus_ca = { }; struct cfdriver scsibus_cd = { - NULL, "scsibus", DV_DULL + NULL, "scsibus", DV_DULL, CD_COCOVM }; struct scsi_quirk_inquiry_pattern { diff --git a/sys/scsi/sd.c b/sys/scsi/sd.c index 9b02314c679..085ad01cd78 100644 --- a/sys/scsi/sd.c +++ b/sys/scsi/sd.c @@ -116,7 +116,7 @@ const struct cfattach sd_ca = { }; struct cfdriver sd_cd = { - NULL, "sd", DV_DISK + NULL, "sd", DV_DISK, CD_COCOVM }; const struct scsi_inquiry_pattern sd_patterns[] = { diff --git a/sys/sys/device.h b/sys/sys/device.h index 5dccec16cf8..2c4171017ec 100644 --- a/sys/sys/device.h +++ b/sys/sys/device.h @@ -139,6 +139,7 @@ struct cfattach { /* For cd_mode, below */ #define CD_INDIRECT 1 #define CD_SKIPHIBERNATE 2 +#define CD_COCOVM 4 struct cfdriver { void **cd_devs; /* devices found */ diff --git a/sys/sys/reboot.h b/sys/sys/reboot.h index bf3e7f82680..1998f21691b 100644 --- a/sys/sys/reboot.h +++ b/sys/sys/reboot.h @@ -59,6 +59,7 @@ #define RB_RESET 0x08000 /* just reset, no cleanup */ #define RB_GOODRANDOM 0x10000 /* excellent random seed loaded */ #define RB_UNHIBERNATE 0x20000 /* unhibernate */ +#define RB_COCOVM 0x40000 /* VM booting with SEV enabled */ /* * Constants for converting boot-style device number to type,