From 236502c1102ac95532683c83ef4defff6c5bda4e Mon Sep 17 00:00:00 2001 From: Roy Franz Date: Thu, 25 Sep 2014 14:27:55 +0200 Subject: [PATCH] EFI: add architecture functions for pre/post ExitBootServices The UEFI ExitBootServices function is invoked to transition the system to the 'runtime' mode of operation, and is done right before transitioning from the EFI loader code into Xen proper. x86 does some arch specific memory management (trampoline) before exit boot services, and the code that transitions from the EFI application state to Xen is architecture specific. This patch adds two functions, one pre and one post ExitBootServices to allow each architecture to to handle these cases in a customized manner. Signed-off-by: Roy Franz Acked-by: Jan Beulich --- xen/arch/x86/efi/efi-boot.h | 50 +++++++++++++++++++++++++++++++++++++ xen/common/efi/boot.c | 42 ++----------------------------- 2 files changed, 52 insertions(+), 40 deletions(-) diff --git a/xen/arch/x86/efi/efi-boot.h b/xen/arch/x86/efi/efi-boot.h index 80b8dfe58a..254783fd8d 100644 --- a/xen/arch/x86/efi/efi-boot.h +++ b/xen/arch/x86/efi/efi-boot.h @@ -198,3 +198,53 @@ static void *__init efi_arch_allocate_mmap_buffer(UINTN map_size) return NULL; return (void *)(long)mbi.mem_upper; } + +static void __init efi_arch_pre_exit_boot(void) +{ + if ( !trampoline_phys ) + { + if ( !cfg.addr ) + blexit(L"No memory for trampoline"); + relocate_trampoline(cfg.addr); + } +} + +static void __init noreturn efi_arch_post_exit_boot(void) +{ + u64 efer; + + efi_arch_relocate_image(__XEN_VIRT_START - xen_phys_start); + memcpy((void *)trampoline_phys, trampoline_start, cfg.size); + + /* Set system registers and transfer control. */ + asm volatile("pushq $0\n\tpopfq"); + rdmsrl(MSR_EFER, efer); + efer |= EFER_SCE; + if ( cpuid_ext_features & (1 << (X86_FEATURE_NX & 0x1f)) ) + efer |= EFER_NX; + wrmsrl(MSR_EFER, efer); + write_cr0(X86_CR0_PE | X86_CR0_MP | X86_CR0_ET | X86_CR0_NE | X86_CR0_WP | + X86_CR0_AM | X86_CR0_PG); + asm volatile ( "mov %[cr4], %%cr4\n\t" + "mov %[cr3], %%cr3\n\t" + "movabs $__start_xen, %[rip]\n\t" + "lgdt gdt_descr(%%rip)\n\t" + "mov stack_start(%%rip), %%rsp\n\t" + "mov %[ds], %%ss\n\t" + "mov %[ds], %%ds\n\t" + "mov %[ds], %%es\n\t" + "mov %[ds], %%fs\n\t" + "mov %[ds], %%gs\n\t" + "movl %[cs], 8(%%rsp)\n\t" + "mov %[rip], (%%rsp)\n\t" + "lretq %[stkoff]-16" + : [rip] "=&r" (efer/* any dead 64-bit variable */) + : [cr3] "r" (idle_pg_table), + [cr4] "r" (mmu_cr4_features), + [cs] "ir" (__HYPERVISOR_CS), + [ds] "r" (__HYPERVISOR_DS), + [stkoff] "i" (STACK_SIZE - sizeof(struct cpu_info)), + "D" (&mbi) + : "memory" ); + for( ; ; ); /* not reached */ +} diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c index f5ea6a5585..11f749ede5 100644 --- a/xen/common/efi/boot.c +++ b/xen/common/efi/boot.c @@ -668,7 +668,6 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable) EFI_GRAPHICS_OUTPUT_MODE_INFORMATION *mode_info; EFI_FILE_HANDLE dir_handle; union string section = { NULL }, name; - u64 efer; bool_t base_video = 0; efi_ih = ImageHandle; @@ -1277,12 +1276,7 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable) efi_arch_process_memory_map(SystemTable, efi_memmap, efi_memmap_size, efi_mdesc_size, mdesc_ver); - if ( !trampoline_phys ) - { - if ( !cfg.addr ) - blexit(L"No memory for trampoline"); - relocate_trampoline(cfg.addr); - } + efi_arch_pre_exit_boot(); status = efi_bs->ExitBootServices(ImageHandle, map_key); if ( EFI_ERROR(status) ) @@ -1296,39 +1290,7 @@ efi_start(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable) efi_memmap = (void *)efi_memmap + DIRECTMAP_VIRT_START; efi_fw_vendor = (void *)efi_fw_vendor + DIRECTMAP_VIRT_START; - efi_arch_relocate_image(__XEN_VIRT_START - xen_phys_start); - memcpy((void *)trampoline_phys, trampoline_start, cfg.size); - - /* Set system registers and transfer control. */ - asm volatile("pushq $0\n\tpopfq"); - rdmsrl(MSR_EFER, efer); - efer |= EFER_SCE; - if ( cpuid_ext_features & (1 << (X86_FEATURE_NX & 0x1f)) ) - efer |= EFER_NX; - wrmsrl(MSR_EFER, efer); - write_cr0(X86_CR0_PE | X86_CR0_MP | X86_CR0_ET | X86_CR0_NE | X86_CR0_WP | - X86_CR0_AM | X86_CR0_PG); - asm volatile ( "mov %[cr4], %%cr4\n\t" - "mov %[cr3], %%cr3\n\t" - "movabs $__start_xen, %[rip]\n\t" - "lgdt gdt_descr(%%rip)\n\t" - "mov stack_start(%%rip), %%rsp\n\t" - "mov %[ds], %%ss\n\t" - "mov %[ds], %%ds\n\t" - "mov %[ds], %%es\n\t" - "mov %[ds], %%fs\n\t" - "mov %[ds], %%gs\n\t" - "movl %[cs], 8(%%rsp)\n\t" - "mov %[rip], (%%rsp)\n\t" - "lretq %[stkoff]-16" - : [rip] "=&r" (efer/* any dead 64-bit variable */) - : [cr3] "r" (idle_pg_table), - [cr4] "r" (mmu_cr4_features), - [cs] "ir" (__HYPERVISOR_CS), - [ds] "r" (__HYPERVISOR_DS), - [stkoff] "i" (STACK_SIZE - sizeof(struct cpu_info)), - "D" (&mbi) - : "memory" ); + efi_arch_post_exit_boot(); for( ; ; ); /* not reached */ } -- 2.30.2