[PATCH v9 08/19] x86: Secure Launch kernel early boot stub
ross.philipson at oracle.com
ross.philipson at oracle.com
Tue Jun 4 10:14:15 PDT 2024
On 5/31/24 4:00 AM, Ard Biesheuvel wrote:
> Hello Ross,
Hi Ard,
>
> On Fri, 31 May 2024 at 03:32, Ross Philipson <ross.philipson at oracle.com> wrote:
>>
>> The Secure Launch (SL) stub provides the entry point for Intel TXT (and
>> later AMD SKINIT) to vector to during the late launch. The symbol
>> sl_stub_entry is that entry point and its offset into the kernel is
>> conveyed to the launching code using the MLE (Measured Launch
>> Environment) header in the structure named mle_header. The offset of the
>> MLE header is set in the kernel_info. The routine sl_stub contains the
>> very early late launch setup code responsible for setting up the basic
>> environment to allow the normal kernel startup_32 code to proceed. It is
>> also responsible for properly waking and handling the APs on Intel
>> platforms. The routine sl_main which runs after entering 64b mode is
>> responsible for measuring configuration and module information before
>> it is used like the boot params, the kernel command line, the TXT heap,
>> an external initramfs, etc.
>>
>> Signed-off-by: Ross Philipson <ross.philipson at oracle.com>
>> ---
>> Documentation/arch/x86/boot.rst | 21 +
>> arch/x86/boot/compressed/Makefile | 3 +-
>> arch/x86/boot/compressed/head_64.S | 30 +
>> arch/x86/boot/compressed/kernel_info.S | 34 ++
>> arch/x86/boot/compressed/sl_main.c | 577 ++++++++++++++++++++
>> arch/x86/boot/compressed/sl_stub.S | 725 +++++++++++++++++++++++++
>> arch/x86/include/asm/msr-index.h | 5 +
>> arch/x86/include/uapi/asm/bootparam.h | 1 +
>> arch/x86/kernel/asm-offsets.c | 20 +
>> 9 files changed, 1415 insertions(+), 1 deletion(-)
>> create mode 100644 arch/x86/boot/compressed/sl_main.c
>> create mode 100644 arch/x86/boot/compressed/sl_stub.S
>>
>> diff --git a/Documentation/arch/x86/boot.rst b/Documentation/arch/x86/boot.rst
>> index 4fd492cb4970..295cdf9bcbdb 100644
>> --- a/Documentation/arch/x86/boot.rst
>> +++ b/Documentation/arch/x86/boot.rst
>> @@ -482,6 +482,14 @@ Protocol: 2.00+
>> - If 1, KASLR enabled.
>> - If 0, KASLR disabled.
>>
>> + Bit 2 (kernel internal): SLAUNCH_FLAG
>> +
>> + - Used internally by the setup kernel to communicate
>> + Secure Launch status to kernel proper.
>> +
>> + - If 1, Secure Launch enabled.
>> + - If 0, Secure Launch disabled.
>> +
>> Bit 5 (write): QUIET_FLAG
>>
>> - If 0, print early messages.
>> @@ -1028,6 +1036,19 @@ Offset/size: 0x000c/4
>>
>> This field contains maximal allowed type for setup_data and setup_indirect structs.
>>
>> +============ =================
>> +Field name: mle_header_offset
>> +Offset/size: 0x0010/4
>> +============ =================
>> +
>> + This field contains the offset to the Secure Launch Measured Launch Environment
>> + (MLE) header. This offset is used to locate information needed during a secure
>> + late launch using Intel TXT. If the offset is zero, the kernel does not have
>> + Secure Launch capabilities. The MLE entry point is called from TXT on the BSP
>> + following a success measured launch. The specific state of the processors is
>> + outlined in the TXT Software Development Guide, the latest can be found here:
>> + https://urldefense.com/v3/__https://www.intel.com/content/dam/www/public/us/en/documents/guides/intel-txt-software-development-guide.pdf__;!!ACWV5N9M2RV99hQ!MdqTLUxfB5YUUOB1qyhkN8TF9HAoGW7yy_2qwZGWz8eb73CYkDXY-h1SeyaZjwzsSWz408D3LgDD8Zmw$
>> +
>>
>
> Could we just repaint this field as the offset relative to the start
> of kernel_info rather than relative to the start of the image? That
> way, there is no need for patch #1, and given that the consumer of
> this field accesses it via kernel_info, I wouldn't expect any issues
> in applying this offset to obtain the actual address.
What you suggest here may be possible with respect to the location of
the MLE header itself, we need to give that more thought. The real issue
though is covered in my response below concerning the fields in the MLE
header.
>
>
>> The Image Checksum
>> ==================
>> diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
>> index 9189a0e28686..9076a248d4b4 100644
>> --- a/arch/x86/boot/compressed/Makefile
>> +++ b/arch/x86/boot/compressed/Makefile
>> @@ -118,7 +118,8 @@ vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o
>> vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_mixed.o
>> vmlinux-objs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
>>
>> -vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o
>> +vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o \
>> + $(obj)/sl_main.o $(obj)/sl_stub.o
>>
>> $(obj)/vmlinux: $(vmlinux-objs-y) FORCE
>> $(call if_changed,ld)
>> diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
>> index 1dcb794c5479..803c9e2e6d85 100644
>> --- a/arch/x86/boot/compressed/head_64.S
>> +++ b/arch/x86/boot/compressed/head_64.S
>> @@ -420,6 +420,13 @@ SYM_CODE_START(startup_64)
>> pushq $0
>> popfq
>>
>> +#ifdef CONFIG_SECURE_LAUNCH
>> + /* Ensure the relocation region is coverd by a PMR */
>
> covered
Ack
>
>> + movq %rbx, %rdi
>> + movl $(_bss - startup_32), %esi
>> + callq sl_check_region
>> +#endif
>> +
>> /*
>> * Copy the compressed kernel to the end of our buffer
>> * where decompression in place becomes safe.
>> @@ -462,6 +469,29 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
>> shrq $3, %rcx
>> rep stosq
>>
>> +#ifdef CONFIG_SECURE_LAUNCH
>> + /*
>> + * Have to do the final early sl stub work in 64b area.
>> + *
>> + * *********** NOTE ***********
>> + *
>> + * Several boot params get used before we get a chance to measure
>> + * them in this call. This is a known issue and we currently don't
>> + * have a solution. The scratch field doesn't matter. There is no
>> + * obvious way to do anything about the use of kernel_alignment or
>> + * init_size though these seem low risk with all the PMR and overlap
>> + * checks in place.
>> + */
>> + movq %r15, %rdi
>> + callq sl_main
>> +
>> + /* Ensure the decompression location is covered by a PMR */
>> + movq %rbp, %rdi
>> + movq output_len(%rip), %rsi
>> + callq sl_check_region
>> +#endif
>> +
>> + pushq %rsi
>
> This looks like a rebase error.
I will need to look closely at this. I remember removing the push/pop we
added but this does seem wrong.
>
>> call load_stage2_idt
>>
>> /* Pass boot_params to initialize_identity_maps() */
>> diff --git a/arch/x86/boot/compressed/kernel_info.S b/arch/x86/boot/compressed/kernel_info.S
>> index c18f07181dd5..e199b87764e9 100644
>> --- a/arch/x86/boot/compressed/kernel_info.S
>> +++ b/arch/x86/boot/compressed/kernel_info.S
>> @@ -28,6 +28,40 @@ SYM_DATA_START(kernel_info)
>> /* Maximal allowed type for setup_data and setup_indirect structs. */
>> .long SETUP_TYPE_MAX
>>
>> + /* Offset to the MLE header structure */
>> +#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
>> + .long rva(mle_header)
>
> ... so this could just be mle_header - kernel_info, and the consumer
> can do the math instead.
While we might be able to do this...
>
>> +#else
>> + .long 0
>> +#endif
>> +
>> kernel_info_var_len_data:
>> /* Empty for time being... */
>> SYM_DATA_END_LABEL(kernel_info, SYM_L_LOCAL, kernel_info_end)
>> +
>> +#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
>> + /*
>> + * The MLE Header per the TXT Specification, section 2.1
>> + * MLE capabilities, see table 4. Capabilities set:
>> + * bit 0: Support for GETSEC[WAKEUP] for RLP wakeup
>> + * bit 1: Support for RLP wakeup using MONITOR address
>> + * bit 2: The ECX register will contain the pointer to the MLE page table
>> + * bit 5: TPM 1.2 family: Details/authorities PCR usage support
>> + * bit 9: Supported format of TPM 2.0 event log - TCG compliant
>> + */
>> +SYM_DATA_START(mle_header)
>> + .long 0x9082ac5a /* UUID0 */
>> + .long 0x74a7476f /* UUID1 */
>> + .long 0xa2555c0f /* UUID2 */
>> + .long 0x42b651cb /* UUID3 */
>> + .long 0x00000034 /* MLE header size */
>> + .long 0x00020002 /* MLE version 2.2 */
>> + .long rva(sl_stub_entry) /* Linear entry point of MLE (virt. address) */
>
> and these should perhaps be relative to mle_header?
... this would be much more problematic. For TXT, the SINIT ACM is the
consumer of this field and it expects it to be relative to the beginning
of the MLE image (i.e. the setup kernl and piggy in this case) and we
have no control over that. We used to fix this value up in the prologue
code for the launch but this was not a clean approach. The same issue
applies to the next comment too. We will have to see what other options
we may be able to adopt here.
>
>> + .long 0x00000000 /* First valid page of MLE */
>> + .long 0x00000000 /* Offset within binary of first byte of MLE */
>> + .long rva(_edata) /* Offset within binary of last byte + 1 of MLE */
>
> and here
See last comment.
>
>> + .long 0x00000227 /* Bit vector of MLE-supported capabilities */
>> + .long 0x00000000 /* Starting linear address of command line (unused) */
>> + .long 0x00000000 /* Ending linear address of command line (unused) */
>> +SYM_DATA_END(mle_header)
>> +#endif
>> diff --git a/arch/x86/boot/compressed/sl_main.c b/arch/x86/boot/compressed/sl_main.c
>> new file mode 100644
>> index 000000000000..61e9baf410fd
>> --- /dev/null
>> +++ b/arch/x86/boot/compressed/sl_main.c
>> @@ -0,0 +1,577 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Secure Launch early measurement and validation routines.
>> + *
>> + * Copyright (c) 2024, Oracle and/or its affiliates.
>> + */
>> +
>> +#include <linux/init.h>
>> +#include <linux/string.h>
>> +#include <linux/linkage.h>
>> +#include <asm/segment.h>
>> +#include <asm/boot.h>
>> +#include <asm/msr.h>
>> +#include <asm/mtrr.h>
>> +#include <asm/processor-flags.h>
>> +#include <asm/asm-offsets.h>
>> +#include <asm/bootparam.h>
>> +#include <asm/bootparam_utils.h>
>> +#include <linux/slr_table.h>
>> +#include <linux/slaunch.h>
>> +#include <crypto/sha1.h>
>> +#include <crypto/sha2.h>
>> +
>> +#define CAPS_VARIABLE_MTRR_COUNT_MASK 0xff
>> +
>> +#define SL_TPM12_LOG 1
>> +#define SL_TPM20_LOG 2
>> +
>> +#define SL_TPM20_MAX_ALGS 2
>> +
>> +#define SL_MAX_EVENT_DATA 64
>> +#define SL_TPM12_LOG_SIZE (sizeof(struct tcg_pcr_event) + \
>> + SL_MAX_EVENT_DATA)
>> +#define SL_TPM20_LOG_SIZE (sizeof(struct tcg_pcr_event2_head) + \
>> + SHA1_DIGEST_SIZE + SHA256_DIGEST_SIZE + \
>> + sizeof(struct tcg_event_field) + \
>> + SL_MAX_EVENT_DATA)
>> +
>> +static void *evtlog_base;
>> +static u32 evtlog_size;
>> +static struct txt_heap_event_log_pointer2_1_element *log20_elem;
>> +static u32 tpm_log_ver = SL_TPM12_LOG;
>> +static struct tcg_efi_specid_event_algs tpm_algs[SL_TPM20_MAX_ALGS] = {0};
>> +
>> +extern u32 sl_cpu_type;
>> +extern u32 sl_mle_start;
>> +
>> +static u64 sl_txt_read(u32 reg)
>> +{
>> + return readq((void *)(u64)(TXT_PRIV_CONFIG_REGS_BASE + reg));
>> +}
>> +
>> +static void sl_txt_write(u32 reg, u64 val)
>> +{
>> + writeq(val, (void *)(u64)(TXT_PRIV_CONFIG_REGS_BASE + reg));
>> +}
>> +
>> +static void __noreturn sl_txt_reset(u64 error)
>> +{
>> + /* Reading the E2STS register acts as a barrier for TXT registers */
>> + sl_txt_write(TXT_CR_ERRORCODE, error);
>> + sl_txt_read(TXT_CR_E2STS);
>> + sl_txt_write(TXT_CR_CMD_UNLOCK_MEM_CONFIG, 1);
>> + sl_txt_read(TXT_CR_E2STS);
>> + sl_txt_write(TXT_CR_CMD_RESET, 1);
>> +
>> + for ( ; ; )
>> + asm volatile ("hlt");
>> +
>> + unreachable();
>> +}
>> +
>> +static u64 sl_rdmsr(u32 reg)
>> +{
>> + u64 lo, hi;
>> +
>> + asm volatile ("rdmsr" : "=a" (lo), "=d" (hi) : "c" (reg));
>> +
>> + return (hi << 32) | lo;
>> +}
>> +
>> +static struct slr_table *sl_locate_and_validate_slrt(void)
>> +{
>> + struct txt_os_mle_data *os_mle_data;
>> + struct slr_table *slrt;
>> + void *txt_heap;
>> +
>> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
>> + os_mle_data = txt_os_mle_data_start(txt_heap);
>> +
>> + if (!os_mle_data->slrt)
>> + sl_txt_reset(SL_ERROR_INVALID_SLRT);
>> +
>> + slrt = (struct slr_table *)os_mle_data->slrt;
>> +
>> + if (slrt->magic != SLR_TABLE_MAGIC)
>> + sl_txt_reset(SL_ERROR_INVALID_SLRT);
>> +
>> + if (slrt->architecture != SLR_INTEL_TXT)
>> + sl_txt_reset(SL_ERROR_INVALID_SLRT);
>> +
>> + return slrt;
>> +}
>> +
>> +static void sl_check_pmr_coverage(void *base, u32 size, bool allow_hi)
>> +{
>> + struct txt_os_sinit_data *os_sinit_data;
>> + void *end = base + size;
>> + void *txt_heap;
>> +
>> + if (!(sl_cpu_type & SL_CPU_INTEL))
>> + return;
>> +
>> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
>> + os_sinit_data = txt_os_sinit_data_start(txt_heap);
>> +
>> + if ((end >= (void *)0x100000000ULL) && (base < (void *)0x100000000ULL))
>> + sl_txt_reset(SL_ERROR_REGION_STRADDLE_4GB);
>> +
>> + /*
>> + * Note that the late stub code validates that the hi PMR covers
>> + * all memory above 4G. At this point the code can only check that
>> + * regions are within the hi PMR but that is sufficient.
>> + */
>> + if ((end > (void *)0x100000000ULL) && (base >= (void *)0x100000000ULL)) {
>
> Better to put the cast on the pointers, given that we are doing
> arithmetic, and use SZ_4G instead of open coding this constant 4
> times.
Good idea, we will do that.
>
>
>
>> + if (allow_hi) {
>> + if (end >= (void *)(os_sinit_data->vtd_pmr_hi_base +
>> + os_sinit_data->vtd_pmr_hi_size))
>> + sl_txt_reset(SL_ERROR_BUFFER_BEYOND_PMR);
>> + } else {
>> + sl_txt_reset(SL_ERROR_REGION_ABOVE_4GB);
>> + }
>> + }
>> +
>> + if (end >= (void *)os_sinit_data->vtd_pmr_lo_size)
>> + sl_txt_reset(SL_ERROR_BUFFER_BEYOND_PMR);
>> +}
>> +
>> +/*
>> + * Some MSRs are modified by the pre-launch code including the MTRRs.
>> + * The early MLE code has to restore these values. This code validates
>> + * the values after they are measured.
>> + */
>> +static void sl_txt_validate_msrs(struct txt_os_mle_data *os_mle_data)
>> +{
>> + struct slr_txt_mtrr_state *saved_bsp_mtrrs;
>> + u64 mtrr_caps, mtrr_def_type, mtrr_var;
>> + struct slr_entry_intel_info *txt_info;
>> + u64 misc_en_msr;
>> + u32 vcnt, i;
>> +
>> + txt_info = (struct slr_entry_intel_info *)os_mle_data->txt_info;
>> + saved_bsp_mtrrs = &txt_info->saved_bsp_mtrrs;
>> +
>> + mtrr_caps = sl_rdmsr(MSR_MTRRcap);
>> + vcnt = (u32)(mtrr_caps & CAPS_VARIABLE_MTRR_COUNT_MASK);
>> +
>> + if (saved_bsp_mtrrs->mtrr_vcnt > vcnt)
>> + sl_txt_reset(SL_ERROR_MTRR_INV_VCNT);
>> + if (saved_bsp_mtrrs->mtrr_vcnt > TXT_OS_MLE_MAX_VARIABLE_MTRRS)
>> + sl_txt_reset(SL_ERROR_MTRR_INV_VCNT);
>> +
>> + mtrr_def_type = sl_rdmsr(MSR_MTRRdefType);
>> + if (saved_bsp_mtrrs->default_mem_type != mtrr_def_type)
>> + sl_txt_reset(SL_ERROR_MTRR_INV_DEF_TYPE);
>> +
>> + for (i = 0; i < saved_bsp_mtrrs->mtrr_vcnt; i++) {
>> + mtrr_var = sl_rdmsr(MTRRphysBase_MSR(i));
>> + if (saved_bsp_mtrrs->mtrr_pair[i].mtrr_physbase != mtrr_var)
>> + sl_txt_reset(SL_ERROR_MTRR_INV_BASE);
>> + mtrr_var = sl_rdmsr(MTRRphysMask_MSR(i));
>> + if (saved_bsp_mtrrs->mtrr_pair[i].mtrr_physmask != mtrr_var)
>> + sl_txt_reset(SL_ERROR_MTRR_INV_MASK);
>> + }
>> +
>> + misc_en_msr = sl_rdmsr(MSR_IA32_MISC_ENABLE);
>> + if (txt_info->saved_misc_enable_msr != misc_en_msr)
>> + sl_txt_reset(SL_ERROR_MSR_INV_MISC_EN);
>> +}
>> +
>> +static void sl_find_drtm_event_log(struct slr_table *slrt)
>> +{
>> + struct txt_os_sinit_data *os_sinit_data;
>> + struct slr_entry_log_info *log_info;
>> + void *txt_heap;
>> +
>> + log_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_LOG_INFO);
>> + if (!log_info)
>> + sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
>> +
>> + evtlog_base = (void *)log_info->addr;
>> + evtlog_size = log_info->size;
>> +
>> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
>> +
>> + /*
>> + * For TPM 2.0, the event log 2.1 extended data structure has to also
>> + * be located and fixed up.
>> + */
>> + os_sinit_data = txt_os_sinit_data_start(txt_heap);
>> +
>> + /*
>> + * Only support version 6 and later that properly handle the
>> + * list of ExtDataElements in the OS-SINIT structure.
>> + */
>> + if (os_sinit_data->version < 6)
>> + sl_txt_reset(SL_ERROR_OS_SINIT_BAD_VERSION);
>> +
>> + /* Find the TPM2.0 logging extended heap element */
>> + log20_elem = tpm20_find_log2_1_element(os_sinit_data);
>> +
>> + /* If found, this implies TPM20 log and family */
>> + if (log20_elem)
>> + tpm_log_ver = SL_TPM20_LOG;
>> +}
>> +
>> +static void sl_validate_event_log_buffer(void)
>> +{
>> + struct txt_os_sinit_data *os_sinit_data;
>> + void *txt_heap, *txt_end;
>> + void *mle_base, *mle_end;
>> + void *evtlog_end;
>> +
>> + if ((u64)evtlog_size > (LLONG_MAX - (u64)evtlog_base))
>> + sl_txt_reset(SL_ERROR_INTEGER_OVERFLOW);
>> + evtlog_end = evtlog_base + evtlog_size;
>> +
>> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
>> + txt_end = txt_heap + sl_txt_read(TXT_CR_HEAP_SIZE);
>> + os_sinit_data = txt_os_sinit_data_start(txt_heap);
>> +
>> + mle_base = (void *)(u64)sl_mle_start;
>> + mle_end = mle_base + os_sinit_data->mle_size;
>> +
>> + /*
>> + * This check is to ensure the event log buffer does not overlap with
>> + * the MLE image.
>> + */
>> + if (evtlog_base >= mle_end && evtlog_end > mle_end)
>> + goto pmr_check; /* above */
>> +
>> + if (evtlog_end <= mle_base && evtlog_base < mle_base)
>> + goto pmr_check; /* below */
>> +
>> + sl_txt_reset(SL_ERROR_MLE_BUFFER_OVERLAP);
>> +
>> +pmr_check:
>> + /*
>> + * The TXT heap is protected by the DPR. If the TPM event log is
>> + * inside the TXT heap, there is no need for a PMR check.
>> + */
>> + if (evtlog_base > txt_heap && evtlog_end < txt_end)
>> + return;
>> +
>> + sl_check_pmr_coverage(evtlog_base, evtlog_size, true);
>> +}
>> +
>> +static void sl_find_event_log_algorithms(void)
>> +{
>> + struct tcg_efi_specid_event_head *efi_head =
>> + (struct tcg_efi_specid_event_head *)(evtlog_base +
>> + log20_elem->first_record_offset +
>> + sizeof(struct tcg_pcr_event));
>> +
>> + if (efi_head->num_algs == 0 || efi_head->num_algs > 2)
>> + sl_txt_reset(SL_ERROR_TPM_NUMBER_ALGS);
>> +
>> + memcpy(&tpm_algs[0], &efi_head->digest_sizes[0],
>> + sizeof(struct tcg_efi_specid_event_algs) * efi_head->num_algs);
>> +}
>> +
>> +static void sl_tpm12_log_event(u32 pcr, u32 event_type,
>> + const u8 *data, u32 length,
>> + const u8 *event_data, u32 event_size)
>> +{
>> + u8 sha1_hash[SHA1_DIGEST_SIZE] = {0};
>> + u8 log_buf[SL_TPM12_LOG_SIZE] = {0};
>> + struct tcg_pcr_event *pcr_event;
>> + u32 total_size;
>> +
>> + pcr_event = (struct tcg_pcr_event *)log_buf;
>> + pcr_event->pcr_idx = pcr;
>> + pcr_event->event_type = event_type;
>> + if (length > 0) {
>> + sha1(data, length, &sha1_hash[0]);
>> + memcpy(&pcr_event->digest[0], &sha1_hash[0], SHA1_DIGEST_SIZE);
>> + }
>> + pcr_event->event_size = event_size;
>> + if (event_size > 0)
>> + memcpy((u8 *)pcr_event + sizeof(struct tcg_pcr_event),
>> + event_data, event_size);
>> +
>> + total_size = sizeof(struct tcg_pcr_event) + event_size;
>> +
>> + if (tpm12_log_event(evtlog_base, evtlog_size, total_size, pcr_event))
>> + sl_txt_reset(SL_ERROR_TPM_LOGGING_FAILED);
>> +}
>> +
>> +static void sl_tpm20_log_event(u32 pcr, u32 event_type,
>> + const u8 *data, u32 length,
>> + const u8 *event_data, u32 event_size)
>> +{
>> + u8 sha256_hash[SHA256_DIGEST_SIZE] = {0};
>> + u8 sha1_hash[SHA1_DIGEST_SIZE] = {0};
>> + u8 log_buf[SL_TPM20_LOG_SIZE] = {0};
>> + struct sha256_state sctx256 = {0};
>> + struct tcg_pcr_event2_head *head;
>> + struct tcg_event_field *event;
>> + u32 total_size;
>> + u16 *alg_ptr;
>> + u8 *dgst_ptr;
>> +
>> + head = (struct tcg_pcr_event2_head *)log_buf;
>> + head->pcr_idx = pcr;
>> + head->event_type = event_type;
>> + total_size = sizeof(struct tcg_pcr_event2_head);
>> + alg_ptr = (u16 *)(log_buf + sizeof(struct tcg_pcr_event2_head));
>> +
>> + for ( ; head->count < 2; head->count++) {
>> + if (!tpm_algs[head->count].alg_id)
>> + break;
>> +
>> + *alg_ptr = tpm_algs[head->count].alg_id;
>> + dgst_ptr = (u8 *)alg_ptr + sizeof(u16);
>> +
>> + if (tpm_algs[head->count].alg_id == TPM_ALG_SHA256 &&
>> + length) {
>> + sha256_init(&sctx256);
>> + sha256_update(&sctx256, data, length);
>> + sha256_final(&sctx256, &sha256_hash[0]);
>> + } else if (tpm_algs[head->count].alg_id == TPM_ALG_SHA1 &&
>> + length) {
>> + sha1(data, length, &sha1_hash[0]);
>> + }
>> +
>> + if (tpm_algs[head->count].alg_id == TPM_ALG_SHA256) {
>> + memcpy(dgst_ptr, &sha256_hash[0], SHA256_DIGEST_SIZE);
>> + total_size += SHA256_DIGEST_SIZE + sizeof(u16);
>> + alg_ptr = (u16 *)((u8 *)alg_ptr + SHA256_DIGEST_SIZE + sizeof(u16));
>> + } else if (tpm_algs[head->count].alg_id == TPM_ALG_SHA1) {
>> + memcpy(dgst_ptr, &sha1_hash[0], SHA1_DIGEST_SIZE);
>> + total_size += SHA1_DIGEST_SIZE + sizeof(u16);
>> + alg_ptr = (u16 *)((u8 *)alg_ptr + SHA1_DIGEST_SIZE + sizeof(u16));
>> + } else {
>> + sl_txt_reset(SL_ERROR_TPM_UNKNOWN_DIGEST);
>> + }
>> + }
>> +
>> + event = (struct tcg_event_field *)(log_buf + total_size);
>> + event->event_size = event_size;
>> + if (event_size > 0)
>> + memcpy((u8 *)event + sizeof(struct tcg_event_field), event_data, event_size);
>> + total_size += sizeof(struct tcg_event_field) + event_size;
>> +
>> + if (tpm20_log_event(log20_elem, evtlog_base, evtlog_size, total_size, &log_buf[0]))
>> + sl_txt_reset(SL_ERROR_TPM_LOGGING_FAILED);
>> +}
>> +
>> +static void sl_tpm_extend_evtlog(u32 pcr, u32 type,
>> + const u8 *data, u32 length, const char *desc)
>> +{
>> + if (tpm_log_ver == SL_TPM20_LOG)
>> + sl_tpm20_log_event(pcr, type, data, length,
>> + (const u8 *)desc, strlen(desc));
>> + else
>> + sl_tpm12_log_event(pcr, type, data, length,
>> + (const u8 *)desc, strlen(desc));
>> +}
>> +
>> +static struct setup_data *sl_handle_setup_data(struct setup_data *curr,
>> + struct slr_policy_entry *entry)
>> +{
>> + struct setup_indirect *ind;
>> + struct setup_data *next;
>> +
>> + if (!curr)
>> + return NULL;
>> +
>> + next = (struct setup_data *)(unsigned long)curr->next;
>> +
>> + /* SETUP_INDIRECT instances have to be handled differently */
>> + if (curr->type == SETUP_INDIRECT) {
>> + ind = (struct setup_indirect *)((u8 *)curr + offsetof(struct setup_data, data));
>> +
>> + sl_check_pmr_coverage((void *)ind->addr, ind->len, true);
>> +
>> + sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
>> + (void *)ind->addr, ind->len,
>> + entry->evt_info);
>> +
>> + return next;
>> + }
>> +
>> + sl_check_pmr_coverage(((u8 *)curr) + sizeof(struct setup_data),
>> + curr->len, true);
>> +
>> + sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
>> + ((u8 *)curr) + sizeof(struct setup_data),
>> + curr->len,
>> + entry->evt_info);
>> +
>> + return next;
>> +}
>> +
>> +static void sl_extend_setup_data(struct slr_policy_entry *entry)
>> +{
>> + struct setup_data *data;
>> +
>> + /*
>> + * Measuring the boot params measured the fixed e820 memory map.
>> + * Measure any setup_data entries including e820 extended entries.
>> + */
>> + data = (struct setup_data *)(unsigned long)entry->entity;
>> + while (data)
>> + data = sl_handle_setup_data(data, entry);
>> +}
>> +
>> +static void sl_extend_slrt(struct slr_policy_entry *entry)
>> +{
>> + struct slr_table *slrt = (struct slr_table *)entry->entity;
>> + struct slr_entry_intel_info *intel_info;
>> +
>> + /*
>> + * In revision one of the SLRT, the only table that needs to be
>> + * measured is the Intel info table. Everything else is meta-data,
>> + * addresses and sizes. Note the size of what to measure is not set.
>> + * The flag SLR_POLICY_IMPLICIT_SIZE leaves it to the measuring code
>> + * to sort out.
>> + */
>> + if (slrt->revision == 1) {
>> + intel_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_INTEL_INFO);
>> + if (!intel_info)
>> + sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
>> +
>> + sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
>> + (void *)entry->entity, sizeof(struct slr_entry_intel_info),
>> + entry->evt_info);
>> + }
>> +}
>> +
>> +static void sl_extend_txt_os2mle(struct slr_policy_entry *entry)
>> +{
>> + struct txt_os_mle_data *os_mle_data;
>> + void *txt_heap;
>> +
>> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
>> + os_mle_data = txt_os_mle_data_start(txt_heap);
>> +
>> + /*
>> + * Version 1 of the OS-MLE heap structure has no fields to measure. It just
>> + * has addresses and sizes and a scratch buffer.
>> + */
>> + if (os_mle_data->version == 1)
>> + return;
>> +}
>> +
>> +static void sl_process_extend_policy(struct slr_table *slrt)
>> +{
>> + struct slr_entry_policy *policy;
>> + u16 i;
>> +
>> + policy = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_ENTRY_POLICY);
>> + if (!policy)
>> + sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
>> +
>> + for (i = 0; i < policy->nr_entries; i++) {
>> + switch (policy->policy_entries[i].entity_type) {
>> + case SLR_ET_SETUP_DATA:
>> + sl_extend_setup_data(&policy->policy_entries[i]);
>> + break;
>> + case SLR_ET_SLRT:
>> + sl_extend_slrt(&policy->policy_entries[i]);
>> + break;
>> + case SLR_ET_TXT_OS2MLE:
>> + sl_extend_txt_os2mle(&policy->policy_entries[i]);
>> + break;
>> + case SLR_ET_UNUSED:
>> + continue;
>> + default:
>> + sl_tpm_extend_evtlog(policy->policy_entries[i].pcr, TXT_EVTYPE_SLAUNCH,
>> + (void *)policy->policy_entries[i].entity,
>> + policy->policy_entries[i].size,
>> + policy->policy_entries[i].evt_info);
>> + }
>> + }
>> +}
>> +
>> +static void sl_process_extend_uefi_config(struct slr_table *slrt)
>> +{
>> + struct slr_entry_uefi_config *uefi_config;
>> + u16 i;
>> +
>> + uefi_config = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_UEFI_CONFIG);
>> +
>> + /* Optionally here depending on how SL kernel was booted */
>> + if (!uefi_config)
>> + return;
>> +
>> + for (i = 0; i < uefi_config->nr_entries; i++) {
>> + sl_tpm_extend_evtlog(uefi_config->uefi_cfg_entries[i].pcr, TXT_EVTYPE_SLAUNCH,
>> + (void *)uefi_config->uefi_cfg_entries[i].cfg,
>> + uefi_config->uefi_cfg_entries[i].size,
>> + uefi_config->uefi_cfg_entries[i].evt_info);
>> + }
>> +}
>> +
>> +asmlinkage __visible void sl_check_region(void *base, u32 size)
>> +{
>> + sl_check_pmr_coverage(base, size, false);
>> +}
>> +
>> +asmlinkage __visible void sl_main(void *bootparams)
>> +{
>> + struct boot_params *bp = (struct boot_params *)bootparams;
>> + struct txt_os_mle_data *os_mle_data;
>> + struct slr_table *slrt;
>> + void *txt_heap;
>> +
>> + /*
>> + * Ensure loadflags do not indicate a secure launch was done
>> + * unless it really was.
>> + */
>> + bp->hdr.loadflags &= ~SLAUNCH_FLAG;
>> +
>> + /*
>> + * Currently only Intel TXT is supported for Secure Launch. Testing
>> + * this value also indicates that the kernel was booted successfully
>> + * through the Secure Launch entry point and is in SMX mode.
>> + */
>> + if (!(sl_cpu_type & SL_CPU_INTEL))
>> + return;
>> +
>> + slrt = sl_locate_and_validate_slrt();
>> +
>> + /* Locate the TPM event log. */
>> + sl_find_drtm_event_log(slrt);
>> +
>> + /* Validate the location of the event log buffer before using it */
>> + sl_validate_event_log_buffer();
>> +
>> + /*
>> + * Find the TPM hash algorithms used by the ACM and recorded in the
>> + * event log.
>> + */
>> + if (tpm_log_ver == SL_TPM20_LOG)
>> + sl_find_event_log_algorithms();
>> +
>> + /*
>> + * Sanitize them before measuring. Set the SLAUNCH_FLAG early since if
>> + * anything fails, the system will reset anyway.
>> + */
>> + sanitize_boot_params(bp);
>> + bp->hdr.loadflags |= SLAUNCH_FLAG;
>> +
>> + sl_check_pmr_coverage(bootparams, PAGE_SIZE, false);
>> +
>> + /* Place event log SL specific tags before and after measurements */
>> + sl_tpm_extend_evtlog(17, TXT_EVTYPE_SLAUNCH_START, NULL, 0, "");
>> +
>> + /* Process all policy entries and extend the measurements to the evtlog */
>> + sl_process_extend_policy(slrt);
>> +
>> + /* Process all EFI config entries and extend the measurements to the evtlog */
>> + sl_process_extend_uefi_config(slrt);
>> +
>> + sl_tpm_extend_evtlog(17, TXT_EVTYPE_SLAUNCH_END, NULL, 0, "");
>> +
>> + /* No PMR check is needed, the TXT heap is covered by the DPR */
>> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
>> + os_mle_data = txt_os_mle_data_start(txt_heap);
>> +
>> + /*
>> + * Now that the OS-MLE data is measured, ensure the MTRR and
>> + * misc enable MSRs are what we expect.
>> + */
>> + sl_txt_validate_msrs(os_mle_data);
>> +}
>> diff --git a/arch/x86/boot/compressed/sl_stub.S b/arch/x86/boot/compressed/sl_stub.S
>> new file mode 100644
>> index 000000000000..24b8f23d5dcc
>> --- /dev/null
>> +++ b/arch/x86/boot/compressed/sl_stub.S
>> @@ -0,0 +1,725 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +
>> +/*
>> + * Secure Launch protected mode entry point.
>> + *
>> + * Copyright (c) 2024, Oracle and/or its affiliates.
>> + */
>> + .code32
>> + .text
>> +#include <linux/linkage.h>
>> +#include <asm/segment.h>
>> +#include <asm/msr.h>
>> +#include <asm/apicdef.h>
>> +#include <asm/trapnr.h>
>> +#include <asm/processor-flags.h>
>> +#include <asm/asm-offsets.h>
>> +#include <asm/bootparam.h>
>> +#include <asm/page_types.h>
>> +#include <asm/irq_vectors.h>
>> +#include <linux/slr_table.h>
>> +#include <linux/slaunch.h>
>> +
>> +/* CPUID: leaf 1, ECX, SMX feature bit */
>> +#define X86_FEATURE_BIT_SMX (1 << 6)
>> +
>> +#define IDT_VECTOR_LO_BITS 0
>> +#define IDT_VECTOR_HI_BITS 6
>> +
>> +/*
>> + * See the comment in head_64.S for detailed information on what this macro
>> + * and others like it are used for. The comment appears right at the top of
>> + * the file.
>> + */
>> +#define rva(X) ((X) - sl_stub_entry)
>> +
>> +/*
>> + * The GETSEC op code is open coded because older versions of
>> + * GCC do not support the getsec mnemonic.
>> + */
>> +.macro GETSEC leaf
>> + pushl %ebx
>> + xorl %ebx, %ebx /* Must be zero for SMCTRL */
>> + movl \leaf, %eax /* Leaf function */
>> + .byte 0x0f, 0x37 /* GETSEC opcode */
>> + popl %ebx
>> +.endm
>> +
>> +.macro TXT_RESET error
>> + /*
>> + * Set a sticky error value and reset. Note the movs to %eax act as
>> + * TXT register barriers.
>> + */
>> + movl \error, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ERRORCODE)
>> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
>> + movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_NO_SECRETS)
>> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
>> + movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_UNLOCK_MEM_CONFIG)
>> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
>> + movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_RESET)
>> +1:
>> + hlt
>> + jmp 1b
>> +.endm
>> +
>> + .code32
>> +SYM_FUNC_START(sl_stub_entry)
>> + cli
>> + cld
>> +
>> + /*
>> + * On entry, %ebx has the entry abs offset to sl_stub_entry. This
>> + * will be correctly scaled using the rva macro and avoid causing
>> + * relocations. Only %cs and %ds segments are known good.
>
> Could you please clarify this? 'scaling' is unidiomatic in this
> context, and actually means something different in my book. AIUI, %ebx
> is guaranteed to carry the actual address of sl_stub_entry(), and
> rva() is used to generate relative references using %ebx as a base, as
> to avoid /absolute/ relocations, which would require fixups at
> runtime.
Yes, we will reword this to be clearer.
>
>
>> + */
>> +
>> + /* Load GDT, set segment regs and lret to __SL32_CS */
>> + leal rva(sl_gdt_desc)(%ebx), %eax
>> + addl %eax, 2(%eax)
>> + lgdt (%eax)
>> +
>> + movl $(__SL32_DS), %eax
>> + movw %ax, %ds
>> + movw %ax, %es
>> + movw %ax, %fs
>> + movw %ax, %gs
>> + movw %ax, %ss
>> +
>> + /*
>> + * Now that %ss is known good, take the first stack for the BSP. The
>> + * AP stacks are only used on Intel.
>> + */
>> + leal rva(sl_stacks_end)(%ebx), %esp
>> +
>> + leal rva(.Lsl_cs)(%ebx), %eax
>> + pushl $(__SL32_CS)
>> + pushl %eax
>> + lret
>> +
>> +.Lsl_cs:
>> + /* Save our base pointer reg and page table for MLE */
>> + pushl %ebx
>> + pushl %ecx
>> +
>> + /* See if SMX feature is supported. */
>> + movl $1, %eax
>> + cpuid
>> + testl $(X86_FEATURE_BIT_SMX), %ecx
>> + jz .Ldo_unknown_cpu
>> +
>> + popl %ecx
>> + popl %ebx
>> +
>> + /* Know it is Intel */
>> + movl $(SL_CPU_INTEL), rva(sl_cpu_type)(%ebx)
>> +
>> + /* Locate the base of the MLE using the page tables in %ecx */
>> + call sl_find_mle_base
>> +
>> + /* Increment CPU count for BSP */
>> + incl rva(sl_txt_cpu_count)(%ebx)
>> +
>> + /*
>> + * Enable SMI with GETSEC[SMCTRL] which were disabled by SENTER.
>> + * NMIs were also disabled by SENTER. Since there is no IDT for the BSP,
>> + * allow the mainline kernel re-enable them in the normal course of
>> + * booting.
>> + */
>> + GETSEC $(SMX_X86_GETSEC_SMCTRL)
>> +
>> + /* Clear the TXT error registers for a clean start of day */
>> + movl $0, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ERRORCODE)
>> + movl $0xffffffff, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ESTS)
>> +
>> + /* On Intel, the zero page address is passed in the TXT heap */
>> + /* Read physical base of heap into EAX */
>> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
>> + /* Read the size of the BIOS data into ECX (first 8 bytes) */
>> + movl (%eax), %ecx
>> + /* Skip over BIOS data and size of OS to MLE data section */
>> + leal 8(%eax, %ecx), %eax
>> +
>> + /* Need to verify the values in the OS-MLE struct passed in */
>> + call sl_txt_verify_os_mle_struct
>> +
>> + /*
>> + * Get the boot params address from the heap. Note %esi and %ebx MUST
>> + * be preserved across calls and operations.
>> + */
>> + movl SL_boot_params_addr(%eax), %esi
>> +
>> + /* Save %ebx so the APs can find their way home */
>> + movl %ebx, (SL_mle_scratch + SL_SCRATCH_AP_EBX)(%eax)
>> +
>> + /* Fetch the AP wake code block address from the heap */
>> + movl SL_ap_wake_block(%eax), %edi
>> + movl %edi, rva(sl_txt_ap_wake_block)(%ebx)
>> +
>> + /* Store the offset in the AP wake block to the jmp address */
>> + movl $(sl_ap_jmp_offset - sl_txt_ap_wake_begin), \
>> + (SL_mle_scratch + SL_SCRATCH_AP_JMP_OFFSET)(%eax)
>> +
>> + /* Store the offset in the AP wake block to the AP stacks block */
>> + movl $(sl_stacks - sl_txt_ap_wake_begin), \
>> + (SL_mle_scratch + SL_SCRATCH_AP_STACKS_OFFSET)(%eax)
>> +
>> + /* %eax still is the base of the OS-MLE block, save it */
>> + pushl %eax
>> +
>> + /* Relocate the AP wake code to the safe block */
>> + call sl_txt_reloc_ap_wake
>> +
>> + /*
>> + * Wake up all APs that are blocked in the ACM and wait for them to
>> + * halt. This should be done before restoring the MTRRs so the ACM is
>> + * still properly in WB memory.
>> + */
>> + call sl_txt_wake_aps
>> +
>> + /* Restore OS-MLE in %eax */
>> + popl %eax
>> +
>> + /*
>> + * %edi is used by this routine to find the MTRRs which are in the SLRT
>> + * in the Intel info.
>> + */
>> + movl SL_txt_info(%eax), %edi
>> + call sl_txt_load_regs
>> +
>> + jmp .Lcpu_setup_done
>> +
>> +.Ldo_unknown_cpu:
>> + /* Non-Intel CPUs are not yet supported */
>> + ud2
>> +
>> +.Lcpu_setup_done:
>> + /*
>> + * Don't enable MCE at this point. The kernel will enable
>> + * it on the BSP later when it is ready.
>> + */
>> +
>> + /* Done, jump to normal 32b pm entry */
>> + jmp startup_32
>> +SYM_FUNC_END(sl_stub_entry)
>> +
>> +SYM_FUNC_START(sl_find_mle_base)
>> + /* %ecx has PDPT, get first PD */
>> + movl (%ecx), %eax
>> + andl $(PAGE_MASK), %eax
>> + /* Get first PT from first PDE */
>> + movl (%eax), %eax
>> + andl $(PAGE_MASK), %eax
>> + /* Get MLE base from first PTE */
>> + movl (%eax), %eax
>> + andl $(PAGE_MASK), %eax
>> +
>> + movl %eax, rva(sl_mle_start)(%ebx)
>> + ret
>> +SYM_FUNC_END(sl_find_mle_base)
>> +
>> +SYM_FUNC_START(sl_check_buffer_mle_overlap)
>> + /* %ecx: buffer begin %edx: buffer end */
>> + /* %ebx: MLE begin %edi: MLE end */
>> + /* %eax: region may be inside MLE */
>> +
>> + cmpl %edi, %ecx
>> + jb .Lnext_check
>> + cmpl %edi, %edx
>> + jbe .Lnext_check
>> + jmp .Lvalid /* Buffer above MLE */
>> +
>> +.Lnext_check:
>> + cmpl %ebx, %edx
>> + ja .Linside_check
>> + cmpl %ebx, %ecx
>> + jae .Linside_check
>> + jmp .Lvalid /* Buffer below MLE */
>> +
>> +.Linside_check:
>> + cmpl $0, %eax
>> + jz .Linvalid
>> + cmpl %ebx, %ecx
>> + jb .Linvalid
>> + cmpl %edi, %edx
>> + ja .Linvalid
>> + jmp .Lvalid /* Buffer in MLE */
>> +
>> +.Linvalid:
>> + TXT_RESET $(SL_ERROR_MLE_BUFFER_OVERLAP)
>> +
>> +.Lvalid:
>> + ret
>> +SYM_FUNC_END(sl_check_buffer_mle_overlap)
>> +
>> +SYM_FUNC_START(sl_txt_verify_os_mle_struct)
>> + pushl %ebx
>> + /*
>> + * %eax points to the base of the OS-MLE struct. Need to also
>> + * read some values from the OS-SINIT struct too.
>> + */
>> + movl -8(%eax), %ecx
>> + /* Skip over OS to MLE data section and size of OS-SINIT structure */
>> + leal (%eax, %ecx), %edx
>> +
>> + /* Load MLE image base absolute offset */
>> + movl rva(sl_mle_start)(%ebx), %ebx
>> +
>> + /* Verify the value of the low PMR base. It should always be 0. */
>> + movl SL_vtd_pmr_lo_base(%edx), %esi
>> + cmpl $0, %esi
>> + jz .Lvalid_pmr_base
>> + TXT_RESET $(SL_ERROR_LO_PMR_BASE)
>> +
>> +.Lvalid_pmr_base:
>> + /* Grab some values from OS-SINIT structure */
>> + movl SL_mle_size(%edx), %edi
>> + addl %ebx, %edi
>> + jc .Loverflow_detected
>> + movl SL_vtd_pmr_lo_size(%edx), %esi
>> +
>> + /* Check the AP wake block */
>> + movl SL_ap_wake_block(%eax), %ecx
>> + movl SL_ap_wake_block_size(%eax), %edx
>> + addl %ecx, %edx
>> + jc .Loverflow_detected
>> + pushl %eax
>> + xorl %eax, %eax
>> + call sl_check_buffer_mle_overlap
>> + popl %eax
>> + cmpl %esi, %edx
>> + ja .Lbuffer_beyond_pmr
>> +
>> + /*
>> + * Check the boot params. Note during a UEFI boot, the boot
>> + * params will be inside the MLE image. Test for this case
>> + * in the overlap case.
>> + */
>> + movl SL_boot_params_addr(%eax), %ecx
>> + movl $(PAGE_SIZE), %edx
>> + addl %ecx, %edx
>> + jc .Loverflow_detected
>> + pushl %eax
>> + movl $1, %eax
>> + call sl_check_buffer_mle_overlap
>> + popl %eax
>> + cmpl %esi, %edx
>> + ja .Lbuffer_beyond_pmr
>> +
>> + /* Check that the AP wake block is big enough */
>> + cmpl $(sl_txt_ap_wake_end - sl_txt_ap_wake_begin), \
>> + SL_ap_wake_block_size(%eax)
>> + jae .Lwake_block_ok
>> + TXT_RESET $(SL_ERROR_WAKE_BLOCK_TOO_SMALL)
>> +
>> +.Lwake_block_ok:
>> + popl %ebx
>> + ret
>> +
>> +.Loverflow_detected:
>> + TXT_RESET $(SL_ERROR_INTEGER_OVERFLOW)
>> +
>> +.Lbuffer_beyond_pmr:
>> + TXT_RESET $(SL_ERROR_BUFFER_BEYOND_PMR)
>> +SYM_FUNC_END(sl_txt_verify_os_mle_struct)
>> +
>> +SYM_FUNC_START(sl_txt_ap_entry)
>> + cli
>> + cld
>> + /*
>> + * The %cs and %ds segments are known good after waking the AP.
>> + * First order of business is to find where we are and
>> + * save it in %ebx.
>> + */
>> +
>> + /* Read physical base of heap into EAX */
>> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
>> + /* Read the size of the BIOS data into ECX (first 8 bytes) */
>> + movl (%eax), %ecx
>> + /* Skip over BIOS data and size of OS to MLE data section */
>> + leal 8(%eax, %ecx), %eax
>> +
>> + /* Saved %ebx from the BSP and stash OS-MLE pointer */
>> + movl (SL_mle_scratch + SL_SCRATCH_AP_EBX)(%eax), %ebx
>> +
>> + /* Save TXT info ptr in %edi for call to sl_txt_load_regs */
>> + movl SL_txt_info(%eax), %edi
>> +
>> + /* Lock and get our stack index */
>> + movl $1, %ecx
>> +.Lspin:
>> + xorl %eax, %eax
>> + lock cmpxchgl %ecx, rva(sl_txt_spin_lock)(%ebx)
>> + pause
>> + jnz .Lspin
>> +
>> + /* Increment the stack index and use the next value inside lock */
>> + incl rva(sl_txt_stack_index)(%ebx)
>> + movl rva(sl_txt_stack_index)(%ebx), %eax
>> +
>> + /* Unlock */
>> + movl $0, rva(sl_txt_spin_lock)(%ebx)
>> +
>> + /* Location of the relocated AP wake block */
>> + movl rva(sl_txt_ap_wake_block)(%ebx), %ecx
>> +
>> + /* Load reloc GDT, set segment regs and lret to __SL32_CS */
>> + lgdt (sl_ap_gdt_desc - sl_txt_ap_wake_begin)(%ecx)
>> +
>> + movl $(__SL32_DS), %edx
>> + movw %dx, %ds
>> + movw %dx, %es
>> + movw %dx, %fs
>> + movw %dx, %gs
>> + movw %dx, %ss
>> +
>> + /* Load our reloc AP stack */
>> + movl $(TXT_BOOT_STACK_SIZE), %edx
>> + mull %edx
>> + leal (sl_stacks_end - sl_txt_ap_wake_begin)(%ecx), %esp
>> + subl %eax, %esp
>> +
>> + /* Switch to AP code segment */
>> + leal rva(.Lsl_ap_cs)(%ebx), %eax
>> + pushl $(__SL32_CS)
>> + pushl %eax
>> + lret
>> +
>> +.Lsl_ap_cs:
>> + /* Load the relocated AP IDT */
>> + lidt (sl_ap_idt_desc - sl_txt_ap_wake_begin)(%ecx)
>> +
>> + /* Fixup MTRRs and misc enable MSR on APs too */
>> + call sl_txt_load_regs
>> +
>> + /* Enable SMI with GETSEC[SMCTRL] */
>> + GETSEC $(SMX_X86_GETSEC_SMCTRL)
>> +
>> + /* IRET-to-self can be used to enable NMIs which SENTER disabled */
>> + leal rva(.Lnmi_enabled_ap)(%ebx), %eax
>> + pushfl
>> + pushl $(__SL32_CS)
>> + pushl %eax
>> + iret
>> +
>> +.Lnmi_enabled_ap:
>> + /* Put APs in X2APIC mode like the BSP */
>> + movl $(MSR_IA32_APICBASE), %ecx
>> + rdmsr
>> + orl $(XAPIC_ENABLE | X2APIC_ENABLE), %eax
>> + wrmsr
>> +
>> + /*
>> + * Basically done, increment the CPU count and jump off to the AP
>> + * wake block to wait.
>> + */
>> + lock incl rva(sl_txt_cpu_count)(%ebx)
>> +
>> + movl rva(sl_txt_ap_wake_block)(%ebx), %eax
>> + jmp *%eax
>> +SYM_FUNC_END(sl_txt_ap_entry)
>> +
>> +SYM_FUNC_START(sl_txt_reloc_ap_wake)
>> + /* Save boot params register */
>> + pushl %esi
>> +
>> + movl rva(sl_txt_ap_wake_block)(%ebx), %edi
>> +
>> + /* Fixup AP IDT and GDT descriptor before relocating */
>> + leal rva(sl_ap_idt_desc)(%ebx), %eax
>> + addl %edi, 2(%eax)
>> + leal rva(sl_ap_gdt_desc)(%ebx), %eax
>> + addl %edi, 2(%eax)
>> +
>> + /*
>> + * Copy the AP wake code and AP GDT/IDT to the protected wake block
>> + * provided by the loader. Destination already in %edi.
>> + */
>> + movl $(sl_txt_ap_wake_end - sl_txt_ap_wake_begin), %ecx
>> + leal rva(sl_txt_ap_wake_begin)(%ebx), %esi
>> + rep movsb
>> +
>> + /* Setup the IDT for the APs to use in the relocation block */
>> + movl rva(sl_txt_ap_wake_block)(%ebx), %ecx
>> + addl $(sl_ap_idt - sl_txt_ap_wake_begin), %ecx
>> + xorl %edx, %edx
>> +
>> + /* Form the default reset vector relocation address */
>> + movl rva(sl_txt_ap_wake_block)(%ebx), %esi
>> + addl $(sl_txt_int_reset - sl_txt_ap_wake_begin), %esi
>> +
>> +1:
>> + cmpw $(NR_VECTORS), %dx
>> + jz .Lap_idt_done
>> +
>> + cmpw $(X86_TRAP_NMI), %dx
>> + jz 2f
>> +
>> + /* Load all other fixed vectors with reset handler */
>> + movl %esi, %eax
>> + movw %ax, (IDT_VECTOR_LO_BITS)(%ecx)
>> + shrl $16, %eax
>> + movw %ax, (IDT_VECTOR_HI_BITS)(%ecx)
>> + jmp 3f
>> +
>> +2:
>> + /* Load single wake NMI IPI vector at the relocation address */
>> + movl rva(sl_txt_ap_wake_block)(%ebx), %eax
>> + addl $(sl_txt_int_nmi - sl_txt_ap_wake_begin), %eax
>> + movw %ax, (IDT_VECTOR_LO_BITS)(%ecx)
>> + shrl $16, %eax
>> + movw %ax, (IDT_VECTOR_HI_BITS)(%ecx)
>> +
>> +3:
>> + incw %dx
>> + addl $8, %ecx
>> + jmp 1b
>> +
>> +.Lap_idt_done:
>> + popl %esi
>> + ret
>> +SYM_FUNC_END(sl_txt_reloc_ap_wake)
>> +
>> +SYM_FUNC_START(sl_txt_load_regs)
>> + /* Save base pointer register */
>> + pushl %ebx
>> +
>> + /*
>> + * On Intel, the original variable MTRRs and Misc Enable MSR are
>> + * restored on the BSP at early boot. Each AP will also restore
>> + * its MTRRs and Misc Enable MSR.
>> + */
>> + pushl %edi
>> + addl $(SL_saved_bsp_mtrrs), %edi
>> + movl (%edi), %ebx
>> + pushl %ebx /* default_mem_type lo */
>> + addl $4, %edi
>> + movl (%edi), %ebx
>> + pushl %ebx /* default_mem_type hi */
>> + addl $4, %edi
>> + movl (%edi), %ebx /* mtrr_vcnt lo, don't care about hi part */
>> + addl $8, %edi /* now at MTRR pair array */
>> + /* Write the variable MTRRs */
>> + movl $(MSR_MTRRphysBase0), %ecx
>> +1:
>> + cmpl $0, %ebx
>> + jz 2f
>> +
>> + movl (%edi), %eax /* MTRRphysBaseX lo */
>> + addl $4, %edi
>> + movl (%edi), %edx /* MTRRphysBaseX hi */
>> + wrmsr
>> + addl $4, %edi
>> + incl %ecx
>> + movl (%edi), %eax /* MTRRphysMaskX lo */
>> + addl $4, %edi
>> + movl (%edi), %edx /* MTRRphysMaskX hi */
>> + wrmsr
>> + addl $4, %edi
>> + incl %ecx
>> +
>> + decl %ebx
>> + jmp 1b
>> +2:
>> + /* Write the default MTRR register */
>> + popl %edx
>> + popl %eax
>> + movl $(MSR_MTRRdefType), %ecx
>> + wrmsr
>> +
>> + /* Return to beginning and write the misc enable msr */
>> + popl %edi
>> + addl $(SL_saved_misc_enable_msr), %edi
>> + movl (%edi), %eax /* saved_misc_enable_msr lo */
>> + addl $4, %edi
>> + movl (%edi), %edx /* saved_misc_enable_msr hi */
>> + movl $(MSR_IA32_MISC_ENABLE), %ecx
>> + wrmsr
>> +
>> + popl %ebx
>> + ret
>> +SYM_FUNC_END(sl_txt_load_regs)
>> +
>> +SYM_FUNC_START(sl_txt_wake_aps)
>> + /* Save boot params register */
>> + pushl %esi
>> +
>> + /* First setup the MLE join structure and load it into TXT reg */
>> + leal rva(sl_gdt)(%ebx), %eax
>> + leal rva(sl_txt_ap_entry)(%ebx), %ecx
>> + leal rva(sl_smx_rlp_mle_join)(%ebx), %edx
>> + movl %eax, SL_rlp_gdt_base(%edx)
>> + movl %ecx, SL_rlp_entry_point(%edx)
>> + movl %edx, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_MLE_JOIN)
>> +
>> + /* Another TXT heap walk to find various values needed to wake APs */
>> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
>> + /* At BIOS data size, find the number of logical processors */
>> + movl (SL_num_logical_procs + 8)(%eax), %edx
>> + /* Skip over BIOS data */
>> + movl (%eax), %ecx
>> + addl %ecx, %eax
>> + /* Skip over OS to MLE */
>> + movl (%eax), %ecx
>> + addl %ecx, %eax
>> + /* At OS-SNIT size, get capabilities to know how to wake up the APs */
>> + movl (SL_capabilities + 8)(%eax), %esi
>> + /* Skip over OS to SNIT */
>> + movl (%eax), %ecx
>> + addl %ecx, %eax
>> + /* At SINIT-MLE size, get the AP wake MONITOR address */
>> + movl (SL_rlp_wakeup_addr + 8)(%eax), %edi
>> +
>> + /* Determine how to wake up the APs */
>> + testl $(1 << TXT_SINIT_MLE_CAP_WAKE_MONITOR), %esi
>> + jz .Lwake_getsec
>> +
>> + /* Wake using MWAIT MONITOR */
>> + movl $1, (%edi)
>> + jmp .Laps_awake
>> +
>> +.Lwake_getsec:
>> + /* Wake using GETSEC(WAKEUP) */
>> + GETSEC $(SMX_X86_GETSEC_WAKEUP)
>> +
>> +.Laps_awake:
>> + /*
>> + * All of the APs are woken up and rendesvous in the relocated wake
>> + * block starting at sl_txt_ap_wake_begin. Wait for all of them to
>> + * halt.
>> + */
>> + pause
>> + cmpl rva(sl_txt_cpu_count)(%ebx), %edx
>> + jne .Laps_awake
>> +
>> + popl %esi
>> + ret
>> +SYM_FUNC_END(sl_txt_wake_aps)
>> +
>> +/* This is the beginning of the relocated AP wake code block */
>> + .global sl_txt_ap_wake_begin
>> +sl_txt_ap_wake_begin:
>> +
>> + /* Get the LAPIC ID for each AP and stash it on the stack */
>> + movl $(MSR_IA32_X2APIC_APICID), %ecx
>> + rdmsr
>> + pushl %eax
>> +
>> + /*
>> + * Get a pointer to the monitor location on this APs stack to test below
>> + * after mwait returns. Currently %esp points to just past the pushed APIC
>> + * ID value.
>> + */
>> + movl %esp, %eax
>> + subl $(TXT_BOOT_STACK_SIZE - 4), %eax
>> + movl $0, (%eax)
>> +
>> + /* Clear ecx/edx so no invalid extensions or hints are passed to monitor */
>> + xorl %ecx, %ecx
>> + xorl %edx, %edx
>> +
>> + /*
>> + * Arm the monitor and wait for it to be poked by he SMP bringup code. The mwait
>> + * instruction can return for a number of reasons. Test to see if it returned
>> + * because the monitor was written to.
>> + */
>> + monitor
>> +
>> +1:
>> + mfence
>> + mwait
>> + movl (%eax), %edx
>> + testl %edx, %edx
>> + jz 1b
>> +
>> + /*
>> + * This is the long absolute jump to the 32b Secure Launch protected mode stub
>> + * code in sl_trampoline_start32() in the rmpiggy. The jump address will be
>> + * fixed in the SMP boot code when the first AP is brought up. This whole area
>> + * is provided and protected in the memory map by the prelaunch code.
>> + */
>> + .byte 0xea
>> +sl_ap_jmp_offset:
>> + .long 0x00000000
>> + .word __SL32_CS
>> +
>> +SYM_FUNC_START(sl_txt_int_nmi)
>> + /* NMI context, just IRET */
>> + iret
>> +SYM_FUNC_END(sl_txt_int_nmi)
>> +
>> +SYM_FUNC_START(sl_txt_int_reset)
>> + TXT_RESET $(SL_ERROR_INV_AP_INTERRUPT)
>> +SYM_FUNC_END(sl_txt_int_reset)
>> +
>> + .balign 8
>> +SYM_DATA_START_LOCAL(sl_ap_idt_desc)
>> + .word sl_ap_idt_end - sl_ap_idt - 1 /* Limit */
>> + .long sl_ap_idt - sl_txt_ap_wake_begin /* Base */
>> +SYM_DATA_END_LABEL(sl_ap_idt_desc, SYM_L_LOCAL, sl_ap_idt_desc_end)
>> +
>> + .balign 8
>> +SYM_DATA_START_LOCAL(sl_ap_idt)
>> + .rept NR_VECTORS
>> + .word 0x0000 /* Offset 15 to 0 */
>> + .word __SL32_CS /* Segment selector */
>> + .word 0x8e00 /* Present, DPL=0, 32b Vector, Interrupt */
>> + .word 0x0000 /* Offset 31 to 16 */
>> + .endr
>> +SYM_DATA_END_LABEL(sl_ap_idt, SYM_L_LOCAL, sl_ap_idt_end)
>> +
>> + .balign 8
>> +SYM_DATA_START_LOCAL(sl_ap_gdt_desc)
>> + .word sl_ap_gdt_end - sl_ap_gdt - 1
>> + .long sl_ap_gdt - sl_txt_ap_wake_begin
>> +SYM_DATA_END_LABEL(sl_ap_gdt_desc, SYM_L_LOCAL, sl_ap_gdt_desc_end)
>> +
>> + .balign 8
>> +SYM_DATA_START_LOCAL(sl_ap_gdt)
>> + .quad 0x0000000000000000 /* NULL */
>> + .quad 0x00cf9a000000ffff /* __SL32_CS */
>> + .quad 0x00cf92000000ffff /* __SL32_DS */
>> +SYM_DATA_END_LABEL(sl_ap_gdt, SYM_L_LOCAL, sl_ap_gdt_end)
>> +
>> + /* Small stacks for BSP and APs to work with */
>> + .balign 64
>> +SYM_DATA_START_LOCAL(sl_stacks)
>> + .fill (TXT_MAX_CPUS * TXT_BOOT_STACK_SIZE), 1, 0
>> +SYM_DATA_END_LABEL(sl_stacks, SYM_L_LOCAL, sl_stacks_end)
>> +
>> +/* This is the end of the relocated AP wake code block */
>> + .global sl_txt_ap_wake_end
>> +sl_txt_ap_wake_end:
>> +
>> + .data
>> + .balign 8
>> +SYM_DATA_START_LOCAL(sl_gdt_desc)
>> + .word sl_gdt_end - sl_gdt - 1
>> + .long sl_gdt - sl_gdt_desc
>> +SYM_DATA_END_LABEL(sl_gdt_desc, SYM_L_LOCAL, sl_gdt_desc_end)
>> +
>> + .balign 8
>> +SYM_DATA_START_LOCAL(sl_gdt)
>> + .quad 0x0000000000000000 /* NULL */
>> + .quad 0x00cf9a000000ffff /* __SL32_CS */
>> + .quad 0x00cf92000000ffff /* __SL32_DS */
>> +SYM_DATA_END_LABEL(sl_gdt, SYM_L_LOCAL, sl_gdt_end)
>> +
>> + .balign 8
>> +SYM_DATA_START_LOCAL(sl_smx_rlp_mle_join)
>> + .long sl_gdt_end - sl_gdt - 1 /* GDT limit */
>> + .long 0x00000000 /* GDT base */
>> + .long __SL32_CS /* Seg Sel - CS (DS, ES, SS = seg_sel+8) */
>> + .long 0x00000000 /* Entry point physical address */
>> +SYM_DATA_END(sl_smx_rlp_mle_join)
>> +
>> +SYM_DATA(sl_cpu_type, .long 0x00000000)
>> +
>> +SYM_DATA(sl_mle_start, .long 0x00000000)
>> +
>> +SYM_DATA_LOCAL(sl_txt_spin_lock, .long 0x00000000)
>> +
>> +SYM_DATA_LOCAL(sl_txt_stack_index, .long 0x00000000)
>> +
>> +SYM_DATA_LOCAL(sl_txt_cpu_count, .long 0x00000000)
>> +
>> +SYM_DATA_LOCAL(sl_txt_ap_wake_block, .long 0x00000000)
>> diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
>> index e022e6eb766c..37f6167f28ba 100644
>> --- a/arch/x86/include/asm/msr-index.h
>> +++ b/arch/x86/include/asm/msr-index.h
>> @@ -348,6 +348,9 @@
>> #define MSR_IA32_RTIT_OUTPUT_BASE 0x00000560
>> #define MSR_IA32_RTIT_OUTPUT_MASK 0x00000561
>>
>> +#define MSR_MTRRphysBase0 0x00000200
>> +#define MSR_MTRRphysMask0 0x00000201
>> +
>> #define MSR_MTRRfix64K_00000 0x00000250
>> #define MSR_MTRRfix16K_80000 0x00000258
>> #define MSR_MTRRfix16K_A0000 0x00000259
>> @@ -849,6 +852,8 @@
>> #define MSR_IA32_APICBASE_ENABLE (1<<11)
>> #define MSR_IA32_APICBASE_BASE (0xfffff<<12)
>>
>> +#define MSR_IA32_X2APIC_APICID 0x00000802
>> +
>> #define MSR_IA32_UCODE_WRITE 0x00000079
>> #define MSR_IA32_UCODE_REV 0x0000008b
>>
>> diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
>> index 9b82eebd7add..7ce283a22d6b 100644
>> --- a/arch/x86/include/uapi/asm/bootparam.h
>> +++ b/arch/x86/include/uapi/asm/bootparam.h
>> @@ -12,6 +12,7 @@
>> /* loadflags */
>> #define LOADED_HIGH (1<<0)
>> #define KASLR_FLAG (1<<1)
>> +#define SLAUNCH_FLAG (1<<2)
>> #define QUIET_FLAG (1<<5)
>> #define KEEP_SEGMENTS (1<<6)
>> #define CAN_USE_HEAP (1<<7)
>> diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
>> index a98020bf31bb..925adce6e2c7 100644
>> --- a/arch/x86/kernel/asm-offsets.c
>> +++ b/arch/x86/kernel/asm-offsets.c
>> @@ -13,6 +13,8 @@
>> #include <linux/hardirq.h>
>> #include <linux/suspend.h>
>> #include <linux/kbuild.h>
>> +#include <linux/slr_table.h>
>> +#include <linux/slaunch.h>
>> #include <asm/processor.h>
>> #include <asm/thread_info.h>
>> #include <asm/sigframe.h>
>> @@ -120,4 +122,22 @@ static void __used common(void)
>> OFFSET(ARIA_CTX_rounds, aria_ctx, rounds);
>> #endif
>>
>> +#ifdef CONFIG_SECURE_LAUNCH
>> + BLANK();
>> + OFFSET(SL_txt_info, txt_os_mle_data, txt_info);
>> + OFFSET(SL_mle_scratch, txt_os_mle_data, mle_scratch);
>> + OFFSET(SL_boot_params_addr, txt_os_mle_data, boot_params_addr);
>> + OFFSET(SL_ap_wake_block, txt_os_mle_data, ap_wake_block);
>> + OFFSET(SL_ap_wake_block_size, txt_os_mle_data, ap_wake_block_size);
>> + OFFSET(SL_saved_misc_enable_msr, slr_entry_intel_info, saved_misc_enable_msr);
>> + OFFSET(SL_saved_bsp_mtrrs, slr_entry_intel_info, saved_bsp_mtrrs);
>> + OFFSET(SL_num_logical_procs, txt_bios_data, num_logical_procs);
>> + OFFSET(SL_capabilities, txt_os_sinit_data, capabilities);
>> + OFFSET(SL_mle_size, txt_os_sinit_data, mle_size);
>> + OFFSET(SL_vtd_pmr_lo_base, txt_os_sinit_data, vtd_pmr_lo_base);
>> + OFFSET(SL_vtd_pmr_lo_size, txt_os_sinit_data, vtd_pmr_lo_size);
>> + OFFSET(SL_rlp_wakeup_addr, txt_sinit_mle_data, rlp_wakeup_addr);
>> + OFFSET(SL_rlp_gdt_base, smx_rlp_mle_join, rlp_gdt_base);
>> + OFFSET(SL_rlp_entry_point, smx_rlp_mle_join, rlp_entry_point);
>> +#endif
>> }
>> --
>> 2.39.3
>>
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