[PATCH v3 2/7] drm/i915/huc: Parse the GSC-enabled HuC binary
Ceraolo Spurio, Daniele
daniele.ceraolospurio at intel.com
Wed May 31 00:06:17 UTC 2023
On 5/30/2023 4:30 PM, John Harrison wrote:
> On 5/26/2023 17:52, Daniele Ceraolo Spurio wrote:
>> The new binaries that support the 2-step authentication contain the
>> legacy-style binary, which we can use for loading the HuC via DMA. To
>> find out where this is located in the image, we need to parse the
>> manifest of the GSC-enabled HuC binary. The manifest consist of a
>> partition header followed by entries, one of which contains the offset
>> we're looking for.
>> Note that the DG2 GSC binary contains entries with the same names, but
>> it doesn't contain a full legacy binary, so we need to skip assigning
>> the dma offset in that case (which we can do by checking the ccs).
>> Also, since we're now parsing the entries, we can extract the HuC
>> version that way instead of using hardcoded offsets.
>>
>> Note that the GSC binary uses the same structures in its binary header,
>> so they've been added in their own header file.
>>
>> v2: fix structure names to match meu defines (s/CPT/CPD/), update commit
>> message, check ccs validity, drop old version location defines.
>>
>> v3: drop references to the MEU tool to reduce confusion, fix log (John)
>>
>> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
>> Cc: Alan Previn <alan.previn.teres.alexis at intel.com>
>> Cc: John Harrison <John.C.Harrison at Intel.com>
>> Reviewed-by: Alan Previn <alan.previn.teres.alexis at intel.com> #v2
>> ---
>> .../drm/i915/gt/uc/intel_gsc_binary_headers.h | 74 ++++++++++
>> drivers/gpu/drm/i915/gt/uc/intel_huc.c | 11 +-
>> drivers/gpu/drm/i915/gt/uc/intel_huc_fw.c | 135 ++++++++++++++++++
>> drivers/gpu/drm/i915/gt/uc/intel_huc_fw.h | 5 +-
>> drivers/gpu/drm/i915/gt/uc/intel_huc_print.h | 21 +++
>> drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 71 +++++----
>> drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h | 2 +
>> drivers/gpu/drm/i915/gt/uc/intel_uc_fw_abi.h | 6 -
>> 8 files changed, 272 insertions(+), 53 deletions(-)
>> create mode 100644
>> drivers/gpu/drm/i915/gt/uc/intel_gsc_binary_headers.h
>> create mode 100644 drivers/gpu/drm/i915/gt/uc/intel_huc_print.h
>>
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_gsc_binary_headers.h
>> b/drivers/gpu/drm/i915/gt/uc/intel_gsc_binary_headers.h
>> new file mode 100644
>> index 000000000000..714f0c256118
>> --- /dev/null
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_gsc_binary_headers.h
>> @@ -0,0 +1,74 @@
>> +/* SPDX-License-Identifier: MIT */
>> +/*
>> + * Copyright © 2023 Intel Corporation
>> + */
>> +
>> +#ifndef _INTEL_GSC_BINARY_HEADERS_H_
>> +#define _INTEL_GSC_BINARY_HEADERS_H_
>> +
>> +#include <linux/types.h>
>> +
>> +/* Code partition directory (CPD) structures */
>> +struct intel_gsc_cpd_header_v2 {
>> + u32 header_marker;
>> +#define INTEL_GSC_CPD_HEADER_MARKER 0x44504324
>> +
>> + u32 num_of_entries;
>> + u8 header_version;
>> + u8 entry_version;
>> + u8 header_length; /* in bytes */
>> + u8 flags;
>> + u32 partition_name;
>> + u32 crc32;
>> +} __packed;
>> +
>> +struct intel_gsc_cpd_entry {
>> + u8 name[12];
>> +
>> + /*
>> + * Bits 0-24: offset from the beginning of the code partition
>> + * Bit 25: huffman compressed
>> + * Bits 26-31: reserved
>> + */
>> + u32 offset;
>> +#define INTEL_GSC_CPD_ENTRY_OFFSET_MASK GENMASK(24, 0)
>> +#define INTEL_GSC_CPD_ENTRY_HUFFMAN_COMP BIT(25)
>> +
>> + /*
>> + * Module/Item length, in bytes. For Huffman-compressed modules,
>> this
>> + * refers to the uncompressed size. For software-compressed
>> modules,
>> + * this refers to the compressed size.
>> + */
>> + u32 length;
>> +
>> + u8 reserved[4];
>> +} __packed;
>> +
>> +struct intel_gsc_version {
>> + u16 major;
>> + u16 minor;
>> + u16 hotfix;
>> + u16 build;
>> +} __packed;
>> +
>> +struct intel_gsc_manifest_header {
>> + u32 header_type; /* 0x4 for manifest type */
>> + u32 header_length; /* in dwords */
>> + u32 header_version;
>> + u32 flags;
>> + u32 vendor;
>> + u32 date;
>> + u32 size; /* In dwords, size of entire manifest (header +
>> extensions) */
>> + u32 header_id;
>> + u32 internal_data;
>> + struct intel_gsc_version fw_version;
>> + u32 security_version;
>> + struct intel_gsc_version meu_kit_version;
>> + u32 meu_manifest_version;
>> + u8 general_data[4];
>> + u8 reserved3[56];
>> + u32 modulus_size; /* in dwords */
>> + u32 exponent_size; /* in dwords */
>> +} __packed;
>> +
>> +#endif
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_huc.c
>> b/drivers/gpu/drm/i915/gt/uc/intel_huc.c
>> index 268e036f8f28..6d795438b3e4 100644
>> --- a/drivers/gpu/drm/i915/gt/uc/intel_huc.c
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_huc.c
>> @@ -6,23 +6,14 @@
>> #include <linux/types.h>
>> #include "gt/intel_gt.h"
>> -#include "gt/intel_gt_print.h"
>> #include "intel_guc_reg.h"
>> #include "intel_huc.h"
>> +#include "intel_huc_print.h"
>> #include "i915_drv.h"
>> #include <linux/device/bus.h>
>> #include <linux/mei_aux.h>
>> -#define huc_printk(_huc, _level, _fmt, ...) \
>> - gt_##_level(huc_to_gt(_huc), "HuC: " _fmt, ##__VA_ARGS__)
>> -#define huc_err(_huc, _fmt, ...) huc_printk((_huc), err, _fmt,
>> ##__VA_ARGS__)
>> -#define huc_warn(_huc, _fmt, ...) huc_printk((_huc), warn, _fmt,
>> ##__VA_ARGS__)
>> -#define huc_notice(_huc, _fmt, ...) huc_printk((_huc), notice,
>> _fmt, ##__VA_ARGS__)
>> -#define huc_info(_huc, _fmt, ...) huc_printk((_huc), info, _fmt,
>> ##__VA_ARGS__)
>> -#define huc_dbg(_huc, _fmt, ...) huc_printk((_huc), dbg, _fmt,
>> ##__VA_ARGS__)
>> -#define huc_probe_error(_huc, _fmt, ...) huc_printk((_huc),
>> probe_error, _fmt, ##__VA_ARGS__)
>> -
>> /**
>> * DOC: HuC
>> *
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.c
>> b/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.c
>> index 534b0aa43316..037d2ad4879d 100644
>> --- a/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.c
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.c
>> @@ -5,11 +5,146 @@
>> #include "gt/intel_gsc.h"
>> #include "gt/intel_gt.h"
>> +#include "intel_gsc_binary_headers.h"
>> #include "intel_huc.h"
>> #include "intel_huc_fw.h"
>> +#include "intel_huc_print.h"
>> #include "i915_drv.h"
>> #include "pxp/intel_pxp_huc.h"
>> +static void get_version_from_gsc_manifest(struct intel_uc_fw_ver
>> *ver, const void *data)
>> +{
>> + const struct intel_gsc_manifest_header *manifest = data;
>> +
>> + ver->major = manifest->fw_version.major;
>> + ver->minor = manifest->fw_version.minor;
>> + ver->patch = manifest->fw_version.hotfix;
>> +}
>> +
>> +static bool css_valid(const void *data, size_t size)
>> +{
>> + const struct uc_css_header *css = data;
>> +
>> + if (unlikely(size < sizeof(struct uc_css_header)))
>> + return false;
>> +
>> + if (css->module_type != 0x6)
>> + return false;
>> +
>> + if (css->module_vendor != PCI_VENDOR_ID_INTEL)
>> + return false;
>> +
>> + return true;
>> +}
>> +
>> +static inline u32 entry_offset(const struct intel_gsc_cpd_entry *entry)
>> +{
>> + return entry->offset & INTEL_GSC_CPD_ENTRY_OFFSET_MASK;
>> +}
>> +
>> +int intel_huc_fw_get_binary_info(struct intel_uc_fw *huc_fw, const
>> void *data, size_t size)
>> +{
>> + struct intel_huc *huc = container_of(huc_fw, struct intel_huc, fw);
>> + const struct intel_gsc_cpd_header_v2 *header = data;
>> + const struct intel_gsc_cpd_entry *entry;
>> + size_t min_size = sizeof(*header);
>> + int i;
>> +
>> + if (!huc_fw->loaded_via_gsc) {
>> + huc_err(huc, "Invalid FW type GSC header parsing!\n");
> I'm still not understanding what this error means. Is it meant to say
> 'Invalid FW type *for* GSC header parsing'?
yes, sorry that was the idea. I'll add the "for"
>
> 'fw->loaded_via_gsc' is set from the blob table, yes? And
> intel_huc_fw_get_binary_info() is only called from
> check_gsc_manifest() which is called from check_fw_header() iff
> fw->loaded_via_gsc is set. So it should be impossible for this test to
> ever fail, yes?
Yes, this should never fail, but with GSC FW the code changes again so I
wanted to make sure I had a check in there in case I got things wrong.
There would be other failures anyway (because the parsing wouldn't work,
so I can drop this check if you think it is redundant.
Daniele
>
> John.
>
>> + return -EINVAL;
>> + }
>> +
>> + if (size < sizeof(*header)) {
>> + huc_err(huc, "FW too small! %zu < %zu\n", size, min_size);
>> + return -ENODATA;
>> + }
>> +
>> + /*
>> + * The GSC-enabled HuC binary starts with a directory header,
>> followed
>> + * by a series of entries. Each entry is identified by a name and
>> + * points to a specific section of the binary containing the
>> relevant
>> + * data. The entries we're interested in are:
>> + * - "HUCP.man": points to the GSC manifest header for the HuC,
>> which
>> + * contains the version info.
>> + * - "huc_fw": points to the legacy-style binary that can be
>> used for
>> + * load via the DMA. This entry only contains a
>> valid CSS
>> + * on binaries for platforms that support 2-step HuC
>> load
>> + * via dma and auth via GSC (like MTL).
>> + *
>> + * --------------------------------------------------
>> + * [ intel_gsc_cpd_header_v2 ]
>> + * --------------------------------------------------
>> + * [ intel_gsc_cpd_entry[] ]
>> + * [ entry1 ]
>> + * [ ... ]
>> + * [ entryX ]
>> + * [ "HUCP.man" ]
>> + * [ ... ]
>> + * [ offset >----------------------------]------o
>> + * [ ... ] |
>> + * [ entryY ] |
>> + * [ "huc_fw" ] |
>> + * [ ... ] |
>> + * [ offset >----------------------------]----------o
>> + * -------------------------------------------------- | |
>> + * | |
>> + * -------------------------------------------------- | |
>> + * [ intel_gsc_manifest_header ]<-----o |
>> + * [ ... ] |
>> + * [ intel_gsc_version fw_version ] |
>> + * [ ... ] |
>> + * -------------------------------------------------- |
>> + * |
>> + * -------------------------------------------------- |
>> + * [ data[] ]<---------o
>> + * [ ... ]
>> + * [ ... ]
>> + * --------------------------------------------------
>> + */
>> +
>> + if (header->header_marker != INTEL_GSC_CPD_HEADER_MARKER) {
>> + huc_err(huc, "invalid marker for CPD header: 0x%08x!\n",
>> + header->header_marker);
>> + return -EINVAL;
>> + }
>> +
>> + /* we only have binaries with header v2 and entry v1 for now */
>> + if (header->header_version != 2 || header->entry_version != 1) {
>> + huc_err(huc, "invalid CPD header/entry version %u:%u!\n",
>> + header->header_version, header->entry_version);
>> + return -EINVAL;
>> + }
>> +
>> + if (header->header_length < sizeof(struct
>> intel_gsc_cpd_header_v2)) {
>> + huc_err(huc, "invalid CPD header length %u!\n",
>> + header->header_length);
>> + return -EINVAL;
>> + }
>> +
>> + min_size = header->header_length + sizeof(*entry) *
>> header->num_of_entries;
>> + if (size < min_size) {
>> + huc_err(huc, "FW too small! %zu < %zu\n", size, min_size);
>> + return -ENODATA;
>> + }
>> +
>> + entry = data + header->header_length;
>> +
>> + for (i = 0; i < header->num_of_entries; i++, entry++) {
>> + if (strcmp(entry->name, "HUCP.man") == 0)
>> + get_version_from_gsc_manifest(&huc_fw->file_selected.ver,
>> + data + entry_offset(entry));
>> +
>> + if (strcmp(entry->name, "huc_fw") == 0) {
>> + u32 offset = entry_offset(entry);
>> + if (offset < size && css_valid(data + offset, size -
>> offset))
>> + huc_fw->dma_start_offset = offset;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> int intel_huc_fw_load_and_auth_via_gsc(struct intel_huc *huc)
>> {
>> int ret;
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.h
>> b/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.h
>> index db42e238b45f..0999ffe6f962 100644
>> --- a/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.h
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_huc_fw.h
>> @@ -7,8 +7,11 @@
>> #define _INTEL_HUC_FW_H_
>> struct intel_huc;
>> +struct intel_uc_fw;
>> +
>> +#include <linux/types.h>
>> int intel_huc_fw_load_and_auth_via_gsc(struct intel_huc *huc);
>> int intel_huc_fw_upload(struct intel_huc *huc);
>> -
>> +int intel_huc_fw_get_binary_info(struct intel_uc_fw *huc_fw, const
>> void *data, size_t size);
>> #endif
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_huc_print.h
>> b/drivers/gpu/drm/i915/gt/uc/intel_huc_print.h
>> new file mode 100644
>> index 000000000000..915d310ee1df
>> --- /dev/null
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_huc_print.h
>> @@ -0,0 +1,21 @@
>> +/* SPDX-License-Identifier: MIT */
>> +/*
>> + * Copyright © 2023 Intel Corporation
>> + */
>> +
>> +#ifndef __INTEL_HUC_PRINT__
>> +#define __INTEL_HUC_PRINT__
>> +
>> +#include "gt/intel_gt.h"
>> +#include "gt/intel_gt_print.h"
>> +
>> +#define huc_printk(_huc, _level, _fmt, ...) \
>> + gt_##_level(huc_to_gt(_huc), "HuC: " _fmt, ##__VA_ARGS__)
>> +#define huc_err(_huc, _fmt, ...) huc_printk((_huc), err, _fmt,
>> ##__VA_ARGS__)
>> +#define huc_warn(_huc, _fmt, ...) huc_printk((_huc), warn, _fmt,
>> ##__VA_ARGS__)
>> +#define huc_notice(_huc, _fmt, ...) huc_printk((_huc), notice,
>> _fmt, ##__VA_ARGS__)
>> +#define huc_info(_huc, _fmt, ...) huc_printk((_huc), info, _fmt,
>> ##__VA_ARGS__)
>> +#define huc_dbg(_huc, _fmt, ...) huc_printk((_huc), dbg, _fmt,
>> ##__VA_ARGS__)
>> +#define huc_probe_error(_huc, _fmt, ...) huc_printk((_huc),
>> probe_error, _fmt, ##__VA_ARGS__)
>> +
>> +#endif /* __INTEL_HUC_PRINT__ */
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
>> b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
>> index 31776c279f32..9ced8dbf1253 100644
>> --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
>> @@ -548,33 +548,6 @@ static void __force_fw_fetch_failures(struct
>> intel_uc_fw *uc_fw, int e)
>> }
>> }
>> -static int check_gsc_manifest(struct intel_gt *gt,
>> - const struct firmware *fw,
>> - struct intel_uc_fw *uc_fw)
>> -{
>> - u32 *dw = (u32 *)fw->data;
>> - u32 version_hi, version_lo;
>> - size_t min_size;
>> -
>> - /* Check the size of the blob before examining buffer contents */
>> - min_size = sizeof(u32) * (HUC_GSC_VERSION_LO_DW + 1);
>> - if (unlikely(fw->size < min_size)) {
>> - gt_warn(gt, "%s firmware %s: invalid size: %zu < %zu\n",
>> - intel_uc_fw_type_repr(uc_fw->type),
>> uc_fw->file_selected.path,
>> - fw->size, min_size);
>> - return -ENODATA;
>> - }
>> -
>> - version_hi = dw[HUC_GSC_VERSION_HI_DW];
>> - version_lo = dw[HUC_GSC_VERSION_LO_DW];
>> -
>> - uc_fw->file_selected.ver.major =
>> FIELD_GET(HUC_GSC_MAJOR_VER_HI_MASK, version_hi);
>> - uc_fw->file_selected.ver.minor =
>> FIELD_GET(HUC_GSC_MINOR_VER_HI_MASK, version_hi);
>> - uc_fw->file_selected.ver.patch =
>> FIELD_GET(HUC_GSC_PATCH_VER_LO_MASK, version_lo);
>> -
>> - return 0;
>> -}
>> -
>> static void uc_unpack_css_version(struct intel_uc_fw_ver *ver, u32
>> css_value)
>> {
>> /* Get version numbers from the CSS header */
>> @@ -631,22 +604,22 @@ static void guc_read_css_info(struct
>> intel_uc_fw *uc_fw, struct uc_css_header *c
>> uc_fw->private_data_size = css->private_data_size;
>> }
>> -static int check_ccs_header(struct intel_gt *gt,
>> - const struct firmware *fw,
>> - struct intel_uc_fw *uc_fw)
>> +static int __check_ccs_header(struct intel_gt *gt,
>> + const void *fw_data, size_t fw_size,
>> + struct intel_uc_fw *uc_fw)
>> {
>> struct uc_css_header *css;
>> size_t size;
>> /* Check the size of the blob before examining buffer
>> contents */
>> - if (unlikely(fw->size < sizeof(struct uc_css_header))) {
>> + if (unlikely(fw_size < sizeof(struct uc_css_header))) {
>> gt_warn(gt, "%s firmware %s: invalid size: %zu < %zu\n",
>> intel_uc_fw_type_repr(uc_fw->type),
>> uc_fw->file_selected.path,
>> - fw->size, sizeof(struct uc_css_header));
>> + fw_size, sizeof(struct uc_css_header));
>> return -ENODATA;
>> }
>> - css = (struct uc_css_header *)fw->data;
>> + css = (struct uc_css_header *)fw_data;
>> /* Check integrity of size values inside CSS header */
>> size = (css->header_size_dw - css->key_size_dw -
>> css->modulus_size_dw -
>> @@ -654,7 +627,7 @@ static int check_ccs_header(struct intel_gt *gt,
>> if (unlikely(size != sizeof(struct uc_css_header))) {
>> gt_warn(gt, "%s firmware %s: unexpected header size: %zu !=
>> %zu\n",
>> intel_uc_fw_type_repr(uc_fw->type),
>> uc_fw->file_selected.path,
>> - fw->size, sizeof(struct uc_css_header));
>> + fw_size, sizeof(struct uc_css_header));
>> return -EPROTO;
>> }
>> @@ -666,10 +639,10 @@ static int check_ccs_header(struct intel_gt *gt,
>> /* At least, it should have header, uCode and RSA. Size of
>> all three. */
>> size = sizeof(struct uc_css_header) + uc_fw->ucode_size +
>> uc_fw->rsa_size;
>> - if (unlikely(fw->size < size)) {
>> + if (unlikely(fw_size < size)) {
>> gt_warn(gt, "%s firmware %s: invalid size: %zu < %zu\n",
>> intel_uc_fw_type_repr(uc_fw->type),
>> uc_fw->file_selected.path,
>> - fw->size, size);
>> + fw_size, size);
>> return -ENOEXEC;
>> }
>> @@ -690,6 +663,32 @@ static int check_ccs_header(struct intel_gt *gt,
>> return 0;
>> }
>> +static int check_gsc_manifest(struct intel_gt *gt,
>> + const struct firmware *fw,
>> + struct intel_uc_fw *uc_fw)
>> +{
>> + if (uc_fw->type != INTEL_UC_FW_TYPE_HUC) {
>> + gt_err(gt, "trying to GSC-parse a non-HuC binary");
>> + return -EINVAL;
>> + }
>> +
>> + intel_huc_fw_get_binary_info(uc_fw, fw->data, fw->size);
>> +
>> + if (uc_fw->dma_start_offset) {
>> + u32 delta = uc_fw->dma_start_offset;
>> + __check_ccs_header(gt, fw->data + delta, fw->size - delta,
>> uc_fw);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int check_ccs_header(struct intel_gt *gt,
>> + const struct firmware *fw,
>> + struct intel_uc_fw *uc_fw)
>> +{
>> + return __check_ccs_header(gt, fw->data, fw->size, uc_fw);
>> +}
>> +
>> static bool is_ver_8bit(struct intel_uc_fw_ver *ver)
>> {
>> return ver->major < 0xFF && ver->minor < 0xFF && ver->patch <
>> 0xFF;
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h
>> b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h
>> index 2be9470eb712..b3daba9526eb 100644
>> --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h
>> @@ -118,6 +118,8 @@ struct intel_uc_fw {
>> u32 ucode_size;
>> u32 private_data_size;
>> + u32 dma_start_offset;
>> +
>> bool loaded_via_gsc;
>> };
>> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw_abi.h
>> b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw_abi.h
>> index 646fa8aa6cf1..7fe405126249 100644
>> --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw_abi.h
>> +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw_abi.h
>> @@ -84,10 +84,4 @@ struct uc_css_header {
>> } __packed;
>> static_assert(sizeof(struct uc_css_header) == 128);
>> -#define HUC_GSC_VERSION_HI_DW 44
>> -#define HUC_GSC_MAJOR_VER_HI_MASK (0xFF << 0)
>> -#define HUC_GSC_MINOR_VER_HI_MASK (0xFF << 16)
>> -#define HUC_GSC_VERSION_LO_DW 45
>> -#define HUC_GSC_PATCH_VER_LO_MASK (0xFF << 0)
>> -
>> #endif /* _INTEL_UC_FW_ABI_H */
>
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