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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 21:00:37 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 21:00:37 +0000 |
commit | 94ac2ab3fff96814d7460a27a0e9d004abbd4128 (patch) | |
tree | 9a4eb8cc234b540b0f4b93363109cdd37a20540b /drivers/hv/hv_common.c | |
parent | Adding debian version 6.8.12-1. (diff) | |
download | linux-94ac2ab3fff96814d7460a27a0e9d004abbd4128.tar.xz linux-94ac2ab3fff96814d7460a27a0e9d004abbd4128.zip |
Merging upstream version 6.9.2.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hv/hv_common.c')
-rw-r--r-- | drivers/hv/hv_common.c | 99 |
1 files changed, 88 insertions, 11 deletions
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index 0285a74363..dde3f9b687 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -20,8 +20,11 @@ #include <linux/sched/task_stack.h> #include <linux/panic_notifier.h> #include <linux/ptrace.h> +#include <linux/random.h> +#include <linux/efi.h> #include <linux/kdebug.h> #include <linux/kmsg_dump.h> +#include <linux/sizes.h> #include <linux/slab.h> #include <linux/dma-map-ops.h> #include <linux/set_memory.h> @@ -227,19 +230,19 @@ static void hv_kmsg_dump(struct kmsg_dumper *dumper, * contain the size of the panic data in that page. Rest of the * registers are no-op when the NOTIFY_MSG flag is set. */ - hv_set_register(HV_REGISTER_CRASH_P0, 0); - hv_set_register(HV_REGISTER_CRASH_P1, 0); - hv_set_register(HV_REGISTER_CRASH_P2, 0); - hv_set_register(HV_REGISTER_CRASH_P3, virt_to_phys(hv_panic_page)); - hv_set_register(HV_REGISTER_CRASH_P4, bytes_written); + hv_set_msr(HV_MSR_CRASH_P0, 0); + hv_set_msr(HV_MSR_CRASH_P1, 0); + hv_set_msr(HV_MSR_CRASH_P2, 0); + hv_set_msr(HV_MSR_CRASH_P3, virt_to_phys(hv_panic_page)); + hv_set_msr(HV_MSR_CRASH_P4, bytes_written); /* * Let Hyper-V know there is crash data available along with * the panic message. */ - hv_set_register(HV_REGISTER_CRASH_CTL, - (HV_CRASH_CTL_CRASH_NOTIFY | - HV_CRASH_CTL_CRASH_NOTIFY_MSG)); + hv_set_msr(HV_MSR_CRASH_CTL, + (HV_CRASH_CTL_CRASH_NOTIFY | + HV_CRASH_CTL_CRASH_NOTIFY_MSG)); } static struct kmsg_dumper hv_kmsg_dumper = { @@ -278,6 +281,14 @@ static void hv_kmsg_dump_register(void) int __init hv_common_init(void) { int i; + union hv_hypervisor_version_info version; + + /* Get information about the Hyper-V host version */ + if (!hv_get_hypervisor_version(&version)) + pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n", + version.major_version, version.minor_version, + version.build_number, version.service_number, + version.service_pack, version.service_branch); if (hv_is_isolation_supported()) sysctl_record_panic_msg = 0; @@ -310,7 +321,7 @@ int __init hv_common_init(void) * Register for panic kmsg callback only if the right * capability is supported by the hypervisor. */ - hyperv_crash_ctl = hv_get_register(HV_REGISTER_CRASH_CTL); + hyperv_crash_ctl = hv_get_msr(HV_MSR_CRASH_CTL); if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) hv_kmsg_dump_register(); @@ -347,6 +358,72 @@ int __init hv_common_init(void) return 0; } +void __init ms_hyperv_late_init(void) +{ + struct acpi_table_header *header; + acpi_status status; + u8 *randomdata; + u32 length, i; + + /* + * Seed the Linux random number generator with entropy provided by + * the Hyper-V host in ACPI table OEM0. + */ + if (!IS_ENABLED(CONFIG_ACPI)) + return; + + status = acpi_get_table("OEM0", 0, &header); + if (ACPI_FAILURE(status) || !header) + return; + + /* + * Since the "OEM0" table name is for OEM specific usage, verify + * that what we're seeing purports to be from Microsoft. + */ + if (strncmp(header->oem_table_id, "MICROSFT", 8)) + goto error; + + /* + * Ensure the length is reasonable. Requiring at least 8 bytes and + * no more than 4K bytes is somewhat arbitrary and just protects + * against a malformed table. Hyper-V currently provides 64 bytes, + * but allow for a change in a later version. + */ + if (header->length < sizeof(*header) + 8 || + header->length > sizeof(*header) + SZ_4K) + goto error; + + length = header->length - sizeof(*header); + randomdata = (u8 *)(header + 1); + + pr_debug("Hyper-V: Seeding rng with %d random bytes from ACPI table OEM0\n", + length); + + add_bootloader_randomness(randomdata, length); + + /* + * To prevent the seed data from being visible in /sys/firmware/acpi, + * zero out the random data in the ACPI table and fixup the checksum. + * The zero'ing is done out of an abundance of caution in avoiding + * potential security risks to the rng. Similarly, reset the table + * length to just the header size so that a subsequent kexec doesn't + * try to use the zero'ed out random data. + */ + for (i = 0; i < length; i++) { + header->checksum += randomdata[i]; + randomdata[i] = 0; + } + + for (i = 0; i < sizeof(header->length); i++) + header->checksum += ((u8 *)&header->length)[i]; + header->length = sizeof(*header); + for (i = 0; i < sizeof(header->length); i++) + header->checksum -= ((u8 *)&header->length)[i]; + +error: + acpi_put_table(header); +} + /* * Hyper-V specific initialization and die code for * individual CPUs that is common across all architectures. @@ -409,7 +486,7 @@ int hv_common_cpu_init(unsigned int cpu) *inputarg = mem; } - msr_vp_index = hv_get_register(HV_REGISTER_VP_INDEX); + msr_vp_index = hv_get_msr(HV_MSR_VP_INDEX); hv_vp_index[cpu] = msr_vp_index; @@ -506,7 +583,7 @@ EXPORT_SYMBOL_GPL(hv_is_hibernation_supported); */ static u64 __hv_read_ref_counter(void) { - return hv_get_register(HV_REGISTER_TIME_REF_COUNT); + return hv_get_msr(HV_MSR_TIME_REF_COUNT); } u64 (*hv_read_reference_counter)(void) = __hv_read_ref_counter; |