| 1 | /* |
| 2 | * SPDX-License-Identifier: GPL-2.0-or-later |
| 3 | * |
| 4 | * print ovmf debug log |
| 5 | * |
| 6 | * see OvmfPkg/Library/MemDebugLogLib/ in edk2 |
| 7 | */ |
| 8 | |
| 9 | #include "qemu/osdep.h" |
| 10 | #include "qemu/units.h" |
| 11 | #include "qemu/target-info-qapi.h" |
| 12 | #include "hw/core/boards.h" |
| 13 | #include "hw/i386/x86.h" |
| 14 | #include "hw/arm/virt.h" |
| 15 | #include "system/dma.h" |
| 16 | #include "monitor/hmp.h" |
| 17 | #include "monitor/monitor.h" |
| 18 | #include "qapi/error.h" |
| 19 | #include "qapi/type-helpers.h" |
| 20 | #include "qapi/qapi-commands-machine.h" |
| 21 | #include "qobject/qdict.h" |
| 22 | |
| 23 | |
| 24 | /* ----------------------------------------------------------------------- */ |
| 25 | /* copy from edk2 */ |
| 26 | |
| 27 | #define MEM_DEBUG_LOG_MAGIC1 0x3167646d666d766f /* "ovmfmdg1" */ |
| 28 | #define MEM_DEBUG_LOG_MAGIC2 0x3267646d666d766f /* "ovmfmdg2" */ |
| 29 | |
| 30 | /* |
| 31 | * Mem Debug Log buffer header. |
| 32 | * The Log buffer is circular. Only the most |
| 33 | * recent messages are retained. Older messages |
| 34 | * will be discarded if the buffer overflows. |
| 35 | * The Debug Log starts just after the header. |
| 36 | */ |
| 37 | typedef struct { |
| 38 | /* |
| 39 | * Magic values |
| 40 | * These fields are used by tools to locate the buffer in |
| 41 | * memory. These MUST be the first two fields of the structure. |
| 42 | * Use a 128 bit Magic to vastly reduce the possibility of |
| 43 | * a collision with random data in memory. |
| 44 | */ |
| 45 | uint64_t Magic1; |
| 46 | uint64_t Magic2; |
| 47 | /* |
| 48 | * Header Size |
| 49 | * This MUST be the third field of the structure |
| 50 | */ |
| 51 | uint64_t HeaderSize; |
| 52 | /* |
| 53 | * Debug log size (minus header) |
| 54 | */ |
| 55 | uint64_t DebugLogSize; |
| 56 | /* |
| 57 | * edk2 uses this for locking access. |
| 58 | */ |
| 59 | uint64_t MemDebugLogLock; |
| 60 | /* |
| 61 | * Debug log head offset |
| 62 | */ |
| 63 | uint64_t DebugLogHeadOffset; |
| 64 | /* |
| 65 | * Debug log tail offset |
| 66 | */ |
| 67 | uint64_t DebugLogTailOffset; |
| 68 | /* |
| 69 | * Flag to indicate if the buffer wrapped and was thus truncated. |
| 70 | */ |
| 71 | uint64_t Truncated; |
| 72 | /* |
| 73 | * Firmware Build Version (PcdFirmwareVersionString) |
| 74 | */ |
| 75 | char FirmwareVersion[128]; |
| 76 | } MEM_DEBUG_LOG_HDR; |
| 77 | |
| 78 | |
| 79 | /* ----------------------------------------------------------------------- */ |
| 80 | /* qemu monitor command */ |
| 81 | |
| 82 | typedef struct { |
| 83 | uint64_t magic1; |
| 84 | uint64_t magic2; |
| 85 | } MemDebugLogMagic; |
| 86 | |
| 87 | /* find log buffer in guest memory by searching for the magic cookie */ |
| 88 | static dma_addr_t find_ovmf_log_range(dma_addr_t start, dma_addr_t end) |
| 89 | { |
| 90 | static const MemDebugLogMagic magic = { |
| 91 | .magic1 = MEM_DEBUG_LOG_MAGIC1, |
| 92 | .magic2 = MEM_DEBUG_LOG_MAGIC2, |
| 93 | }; |
| 94 | MemDebugLogMagic check; |
| 95 | dma_addr_t step = 4 * KiB; |
| 96 | dma_addr_t offset; |
| 97 | |
| 98 | for (offset = start; offset < end; offset += step) { |
| 99 | if (dma_memory_read(&address_space_memory, offset, |
| 100 | &check, sizeof(check), |
| 101 | MEMTXATTRS_UNSPECIFIED)) { |
| 102 | /* dma error -> stop searching */ |
| 103 | break; |
| 104 | } |
| 105 | if (memcmp(&magic, &check, sizeof(check)) == 0) { |
| 106 | return offset; |
| 107 | } |
| 108 | } |
| 109 | return (dma_addr_t)-1; |
| 110 | } |
| 111 | |
| 112 | static dma_addr_t find_ovmf_log(void) |
| 113 | { |
| 114 | MachineState *ms = MACHINE(qdev_get_machine()); |
| 115 | dma_addr_t start, end, offset; |
| 116 | |
| 117 | if (target_arch() == SYS_EMU_TARGET_X86_64 && |
| 118 | object_dynamic_cast(OBJECT(ms), TYPE_X86_MACHINE)) { |
| 119 | X86MachineState *x86ms = X86_MACHINE(ms); |
| 120 | |
| 121 | /* early log buffer, static allocation in memfd, sec + early pei */ |
| 122 | offset = find_ovmf_log_range(0x800000, 0x900000); |
| 123 | if (offset != -1) { |
| 124 | return offset; |
| 125 | } |
| 126 | |
| 127 | /* |
| 128 | * normal log buffer, dynamically allocated close to end of low memory, |
| 129 | * late pei + dxe phase |
| 130 | */ |
| 131 | end = x86ms->below_4g_mem_size; |
| 132 | start = end - MIN(end, 128 * MiB); |
| 133 | return find_ovmf_log_range(start, end); |
| 134 | } |
| 135 | |
| 136 | if (target_arch() == SYS_EMU_TARGET_AARCH64 && |
| 137 | object_dynamic_cast(OBJECT(ms), TYPE_VIRT_MACHINE)) { |
| 138 | VirtMachineState *vms = VIRT_MACHINE(ms); |
| 139 | |
| 140 | /* edk2 ArmVirt firmware allocations are in the first 128 MB */ |
| 141 | start = vms->memmap[VIRT_MEM].base; |
| 142 | end = start + 128 * MiB; |
| 143 | return find_ovmf_log_range(start, end); |
| 144 | } |
| 145 | |
| 146 | return (dma_addr_t)-1; |
| 147 | } |
| 148 | |
| 149 | static void handle_ovmf_log_range(GString *out, |
| 150 | dma_addr_t start, |
| 151 | dma_addr_t end, |
| 152 | Error **errp) |
| 153 | { |
| 154 | if (start > end) { |
| 155 | return; |
| 156 | } |
| 157 | |
| 158 | size_t len = end - start; |
| 159 | g_string_set_size(out, out->len + len); |
| 160 | if (dma_memory_read(&address_space_memory, start, |
| 161 | out->str + (out->len - len), |
| 162 | len, MEMTXATTRS_UNSPECIFIED)) { |
| 163 | error_setg(errp, "can not read firmware log buffer contents"); |
| 164 | return; |
| 165 | } |
| 166 | } |
| 167 | |
| 168 | FirmwareLog *qmp_query_firmware_log(bool have_max_size, uint64_t max_size, |
| 169 | Error **errp) |
| 170 | { |
| 171 | MEM_DEBUG_LOG_HDR header; |
| 172 | dma_addr_t offset, base; |
| 173 | FirmwareLog *ret; |
| 174 | g_autoptr(GString) log = g_string_new(""); |
| 175 | |
| 176 | offset = find_ovmf_log(); |
| 177 | if (offset == -1) { |
| 178 | error_setg(errp, "firmware log buffer not found"); |
| 179 | return NULL; |
| 180 | } |
| 181 | |
| 182 | if (dma_memory_read(&address_space_memory, offset, |
| 183 | &header, sizeof(header), |
| 184 | MEMTXATTRS_UNSPECIFIED)) { |
| 185 | error_setg(errp, "can not read firmware log buffer header"); |
| 186 | return NULL; |
| 187 | } |
| 188 | |
| 189 | if (header.DebugLogHeadOffset > header.DebugLogSize || |
| 190 | header.DebugLogTailOffset > header.DebugLogSize) { |
| 191 | error_setg(errp, "firmware log buffer header is invalid"); |
| 192 | return NULL; |
| 193 | } |
| 194 | |
| 195 | if (have_max_size) { |
| 196 | if (max_size > MiB) { |
| 197 | error_setg(errp, "parameter 'max-size' exceeds 1MiB"); |
| 198 | return NULL; |
| 199 | } |
| 200 | } else { |
| 201 | max_size = MiB; |
| 202 | } |
| 203 | |
| 204 | /* adjust header.DebugLogHeadOffset so we return at most maxsize bytes */ |
| 205 | if (header.DebugLogHeadOffset > header.DebugLogTailOffset) { |
| 206 | /* wrap around */ |
| 207 | if (header.DebugLogTailOffset > max_size) { |
| 208 | header.DebugLogHeadOffset = header.DebugLogTailOffset - max_size; |
| 209 | } else { |
| 210 | uint64_t max_chunk = max_size - header.DebugLogTailOffset; |
| 211 | if (header.DebugLogSize > max_chunk && |
| 212 | header.DebugLogHeadOffset < header.DebugLogSize - max_chunk) { |
| 213 | header.DebugLogHeadOffset = header.DebugLogSize - max_chunk; |
| 214 | } |
| 215 | } |
| 216 | } else { |
| 217 | if (header.DebugLogTailOffset > max_size && |
| 218 | header.DebugLogHeadOffset < header.DebugLogTailOffset - max_size) { |
| 219 | header.DebugLogHeadOffset = header.DebugLogTailOffset - max_size; |
| 220 | } |
| 221 | } |
| 222 | |
| 223 | base = offset + header.HeaderSize; |
| 224 | if (header.DebugLogHeadOffset > header.DebugLogTailOffset) { |
| 225 | /* wrap around */ |
| 226 | handle_ovmf_log_range(log, |
| 227 | base + header.DebugLogHeadOffset, |
| 228 | base + header.DebugLogSize, |
| 229 | errp); |
| 230 | if (*errp) { |
| 231 | return NULL; |
| 232 | } |
| 233 | handle_ovmf_log_range(log, |
| 234 | base + 0, |
| 235 | base + header.DebugLogTailOffset, |
| 236 | errp); |
| 237 | if (*errp) { |
| 238 | return NULL; |
| 239 | } |
| 240 | } else { |
| 241 | handle_ovmf_log_range(log, |
| 242 | base + header.DebugLogHeadOffset, |
| 243 | base + header.DebugLogTailOffset, |
| 244 | errp); |
| 245 | if (*errp) { |
| 246 | return NULL; |
| 247 | } |
| 248 | } |
| 249 | |
| 250 | ret = g_new0(FirmwareLog, 1); |
| 251 | if (header.FirmwareVersion[0] != '\0') { |
| 252 | ret->version = g_strndup(header.FirmwareVersion, |
| 253 | sizeof(header.FirmwareVersion)); |
| 254 | } |
| 255 | ret->log = g_base64_encode((const guchar *)log->str, log->len); |
| 256 | return ret; |
| 257 | } |
| 258 | |
| 259 | #ifdef CONFIG_HMP |
| 260 | void hmp_info_firmware_log(MonitorHMP *hmp, const QDict *qdict) |
| 261 | { |
| 262 | g_autofree gchar *log_esc = NULL; |
| 263 | g_autofree guchar *log_out = NULL; |
| 264 | Error *err = NULL; |
| 265 | g_autoptr(FirmwareLog) log = NULL; |
| 266 | gsize log_len; |
| 267 | int64_t maxsize; |
| 268 | |
| 269 | maxsize = qdict_get_try_int(qdict, "max-size", -1); |
| 270 | log = qmp_query_firmware_log(maxsize != -1, (uint64_t)maxsize, &err); |
| 271 | if (err) { |
| 272 | hmp_handle_error(hmp, err); |
| 273 | return; |
| 274 | } |
| 275 | |
| 276 | g_assert(log != NULL); |
| 277 | g_assert(log->log != NULL); |
| 278 | |
| 279 | if (log->version) { |
| 280 | g_autofree gchar *esc = g_strescape(log->version, NULL); |
| 281 | monitor_hmp_printf(hmp, "[ firmware version: %s ]\n", esc); |
| 282 | } |
| 283 | |
| 284 | log_out = g_base64_decode(log->log, &log_len); |
| 285 | log_esc = g_strescape((gchar *)log_out, "\r\n"); |
| 286 | monitor_hmp_printf(hmp, "%s\n", log_esc); |
| 287 | } |
| 288 | #endif |