From: Nuno Das Neves <[email protected]> Move hv_current_partition_id and hv_get_partition_id() to hv_common.c. These aren't specific to x86_64 and will be needed by common code.
Set hv_current_partition_id to HV_PARTITION_ID_SELF by default. Use a stack variable for the output of the hypercall. This allows moving the call of hv_get_partition_id() to hv_common_init() before the percpu pages are initialized. Remove the BUG()s. Failing to get the id need not crash the machine. Signed-off-by: Nuno Das Neves <[email protected]> --- arch/x86/hyperv/hv_init.c | 26 -------------------------- arch/x86/include/asm/mshyperv.h | 2 -- drivers/hv/hv_common.c | 23 +++++++++++++++++++++++ include/asm-generic/mshyperv.h | 1 + 4 files changed, 24 insertions(+), 28 deletions(-) diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 173005e6a95d..6b9f6f9f704d 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -34,9 +34,6 @@ #include <clocksource/hyperv_timer.h> #include <linux/highmem.h> -u64 hv_current_partition_id = ~0ull; -EXPORT_SYMBOL_GPL(hv_current_partition_id); - void *hv_hypercall_pg; EXPORT_SYMBOL_GPL(hv_hypercall_pg); @@ -393,24 +390,6 @@ static void __init hv_stimer_setup_percpu_clockev(void) old_setup_percpu_clockev(); } -static void __init hv_get_partition_id(void) -{ - struct hv_get_partition_id *output_page; - u64 status; - unsigned long flags; - - local_irq_save(flags); - output_page = *this_cpu_ptr(hyperv_pcpu_output_arg); - status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page); - if (!hv_result_success(status)) { - /* No point in proceeding if this failed */ - pr_err("Failed to get partition ID: %lld\n", status); - BUG(); - } - hv_current_partition_id = output_page->partition_id; - local_irq_restore(flags); -} - #if IS_ENABLED(CONFIG_HYPERV_VTL_MODE) static u8 __init get_vtl(void) { @@ -605,11 +584,6 @@ void __init hyperv_init(void) register_syscore_ops(&hv_syscore_ops); - if (cpuid_ebx(HYPERV_CPUID_FEATURES) & HV_ACCESS_PARTITION_ID) - hv_get_partition_id(); - - BUG_ON(hv_root_partition && hv_current_partition_id == ~0ull); - #ifdef CONFIG_PCI_MSI /* * If we're running as root, we want to create our own PCI MSI domain. diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index f91ab1e75f9f..8d3ada3e8d0d 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -43,8 +43,6 @@ extern bool hyperv_paravisor_present; extern void *hv_hypercall_pg; -extern u64 hv_current_partition_id; - extern union hv_ghcb * __percpu *hv_ghcb_pg; bool hv_isolation_type_snp(void); diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index af5d1dc451f6..1da19b64ef16 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -31,6 +31,9 @@ #include <hyperv/hvhdk.h> #include <asm/mshyperv.h> +u64 hv_current_partition_id = HV_PARTITION_ID_SELF; +EXPORT_SYMBOL_GPL(hv_current_partition_id); + /* * hv_root_partition, ms_hyperv and hv_nested are defined here with other * Hyper-V specific globals so they are shared across all architectures and are @@ -283,6 +286,23 @@ static inline bool hv_output_page_exists(void) return hv_root_partition || IS_ENABLED(CONFIG_HYPERV_VTL_MODE); } +static void __init hv_get_partition_id(void) +{ + /* + * Note in this case the output can be on the stack because it is just + * a single u64 and hence won't cross a page boundary. + */ + struct hv_get_partition_id output; + u64 status; + + status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, &output); + if (!hv_result_success(status)) { + pr_err("Hyper-V: failed to get partition ID: %#lx\n", status); + return; + } + hv_current_partition_id = output.partition_id; +} + int __init hv_common_init(void) { int i; @@ -298,6 +318,9 @@ int __init hv_common_init(void) if (hv_is_isolation_supported()) sysctl_record_panic_msg = 0; + if (ms_hyperv.priv_high & HV_ACCESS_PARTITION_ID) + hv_get_partition_id(); + /* * Hyper-V expects to get crash register data or kmsg when * crash enlightment is available and system crashes. Set diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index a7bbe504e4f3..98100466e0b2 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -58,6 +58,7 @@ struct ms_hyperv_info { }; extern struct ms_hyperv_info ms_hyperv; extern bool hv_nested; +extern u64 hv_current_partition_id; extern void * __percpu *hyperv_pcpu_input_arg; extern void * __percpu *hyperv_pcpu_output_arg; -- 2.34.1
