Thanks for the info Dave.
Unfortunately, I cannot run crash live on the machine because the VM is in hung state right now. After resetting the VM(by tomorrow), will check for KASLR and phys_base and try the suggested option.

The complete output of crash is below:

[root@gt-Server2-gmt user]# crash -d8 /home/mfusion/vmem_vmss_jan26/usr/lib/debug/usr/lib/modules/4.14.11-coreos/vmlinux /home/mfusion/vmem_vmss_jan26/usr/lib/modules/4.14.11-coreos/build/System.map /home/mfusion/vmem_vmss_jan26/gt-Server2-gmt-612746ca.vmss

crash 7.1.9-3.fc27 
Copyright (C) 2002-2016 Red Hat, Inc. 
Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation 
Copyright (C) 1999-2006 Hewlett-Packard Co 
Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited 
Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. 
Copyright (C) 2005, 2011 NEC Corporation 
Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. 
Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. 
This program is free software, covered by the GNU General Public License, 
and you are welcome to change it and/or distribute copies of it under 
certain conditions. Enter "help copying" to see the conditions. 
This program has absolutely no warranty. Enter "help warranty" for details. 

crash: diskdump / compressed kdump: dump does not have panic dump header 
crash: sadump: read dump device as media format 
crash: sadump: does not have partition header 
vmw: Header: id=bed2bed2 version=8 numgroups=95 
vmw: Checkpoint is 64-bit 
vmw: Group: Checkpoint offset=0x1dbc size=0x0x3ab. 
vmw: Group: GuestVars offset=0x2167 size=0x0xa3. 
vmw: Group: cpuid offset=0x220a size=0x0x5e0e. 
vmw: Group: cpu offset=0x8018 size=0x0x615bb. 
vmw: Group: BusMemSample offset=0x695d3 size=0x0x1c. 
vmw: Group: UUIDVMX offset=0x695ef size=0x0x2e. 
vmw: Group: StateLogger offset=0x6961d size=0x0x2. 
vmw: Group: memory offset=0x6961f size=0x0xa8. 
vmw: Item align_mask[0][0] => position=0x69633 size=0x4: 0000FFFF 
vmw: Item regionsCount => position=0x69645 size=0x4: 00000002 
vmw: Item regionPageNum[0] => position=0x6965c size=0x4: 00000000 
vmw: Item regionPPN[0] => position=0x6966f size=0x4: 00000000 
vmw: Item regionSize[0] => position=0x69683 size=0x4: 000C0000 
vmw: Item regionPageNum[1] => position=0x6969a size=0x4: 000C0000 
vmw: Item regionPPN[1] => position=0x696ad size=0x4: 00100000 
vmw: Item regionSize[1] => position=0x696c1 size=0x4: 00E40000 
vmw: Group: MStats offset=0x696c7 size=0x0x1936. 
vmw: Group: Snapshot offset=0x6affd size=0x0x4b9c. 
vmw: Group: pic offset=0x6fb99 size=0x0x511. 
vmw: Group: FTCpt offset=0x700aa size=0x0x2. 
vmw: Group: ide1:0 offset=0x700ac size=0x0x16e. 
vmw: Group: scsi0:0 offset=0x7021a size=0x0x46. 
vmw: Group: Migrate offset=0x70260 size=0x0x2. 
vmw: Group: TimeTracker offset=0x70262 size=0x0x99. 
vmw: Group: Backdoor offset=0x702fb size=0x0x2e. 
vmw: Group: PCI offset=0x70329 size=0x0x13. 
vmw: Group: Cs440bx offset=0x7033c size=0x0x40539. 
vmw: Group: ExtCfgDevice offset=0xb0875 size=0x0x30. 
vmw: Group: Floppy offset=0xb08a5 size=0x0x918c. 
vmw: Group: AcpiNotify offset=0xb9a31 size=0x0x1b. 
vmw: Group: vcpuHotPlug offset=0xb9a4c size=0x0xf5. 
vmw: Group: devHP offset=0xb9b41 size=0x0x86. 
vmw: Group: ACPIWake offset=0xb9bc7 size=0x0x1b. 
vmw: Group: DevicesPowerOn offset=0xb9be2 size=0x0x2. 
vmw: Group: PCIBridge0 offset=0xb9be4 size=0x0x272. 
vmw: Group: PCIBridge4 offset=0xb9e56 size=0x0x48e. 
vmw: Group: pciBridge4:1 offset=0xba2e4 size=0x0x48e. 
vmw: Group: pciBridge4:2 offset=0xba772 size=0x0x48e. 
vmw: Group: pciBridge4:3 offset=0xbac00 size=0x0x48e. 
vmw: Group: pciBridge4:4 offset=0xbb08e size=0x0x48e. 
vmw: Group: pciBridge4:5 offset=0xbb51c size=0x0x48e. 
vmw: Group: pciBridge4:6 offset=0xbb9aa size=0x0x48e. 
vmw: Group: pciBridge4:7 offset=0xbbe38 size=0x0x48e. 
vmw: Group: PCIBridge5 offset=0xbc2c6 size=0x0x48e. 
vmw: Group: pciBridge5:1 offset=0xbc754 size=0x0x48e. 
vmw: Group: pciBridge5:2 offset=0xbcbe2 size=0x0x48e. 
vmw: Group: pciBridge5:3 offset=0xbd070 size=0x0x48e. 
vmw: Group: pciBridge5:4 offset=0xbd4fe size=0x0x48e. 
vmw: Group: pciBridge5:5 offset=0xbd98c size=0x0x48e. 
vmw: Group: pciBridge5:6 offset=0xbde1a size=0x0x48e. 
vmw: Group: pciBridge5:7 offset=0xbe2a8 size=0x0x48e. 
vmw: Group: PCIBridge6 offset=0xbe736 size=0x0x48e. 
vmw: Group: pciBridge6:1 offset=0xbebc4 size=0x0x48e. 
vmw: Group: pciBridge6:2 offset=0xbf052 size=0x0x48e. 
vmw: Group: pciBridge6:3 offset=0xbf4e0 size=0x0x48e. 
vmw: Group: pciBridge6:4 offset=0xbf96e size=0x0x48e. 
vmw: Group: pciBridge6:5 offset=0xbfdfc size=0x0x48e. 
vmw: Group: pciBridge6:6 offset=0xc028a size=0x0x48e. 
vmw: Group: pciBridge6:7 offset=0xc0718 size=0x0x48e. 
vmw: Group: PCIBridge7 offset=0xc0ba6 size=0x0x48e. 
vmw: Group: pciBridge7:1 offset=0xc1034 size=0x0x48e. 
vmw: Group: pciBridge7:2 offset=0xc14c2 size=0x0x48e. 
vmw: Group: pciBridge7:3 offset=0xc1950 size=0x0x48e. 
vmw: Group: pciBridge7:4 offset=0xc1dde size=0x0x48e. 
vmw: Group: pciBridge7:5 offset=0xc226c size=0x0x48e. 
vmw: Group: pciBridge7:6 offset=0xc26fa size=0x0x48e. 
vmw: Group: pciBridge7:7 offset=0xc2b88 size=0x0x48e. 
vmw: Group: vide offset=0xc3016 size=0x0x10bb7. 
vmw: Group: SCSI0 offset=0xd3bcd size=0x0x1200f. 
vmw: Group: VGA offset=0xe5bdc size=0x0x404aa. 
vmw: Group: SVGA offset=0x126086 size=0x0xa6e6. 
vmw: Group: Ethernet0 offset=0x13076c size=0x0x15312. 
vmw: Group: hpet0 offset=0x145a7e size=0x0xb4a. 
vmw: Group: ich7m.hpet offset=0x1465c8 size=0x0xb4a. 
vmw: Group: vmci0 offset=0x147112 size=0x0x11b0. 
vmw: Group: OEMDevice offset=0x1482c2 size=0x0x17. 
vmw: Group: HotButton offset=0x1482d9 size=0x0x36. 
vmw: Group: vsock offset=0x14830f size=0x0x33a. 
vmw: Group: GuestMsg offset=0x148649 size=0x0xcf. 
vmw: Group: GuestRpc offset=0x148718 size=0x0x3d2. 
vmw: Group: Timer offset=0x148aea size=0x0x308. 
vmw: Group: ACPI offset=0x148df2 size=0x0x3a. 
vmw: Group: XPMode offset=0x148e2c size=0x0xb. 
vmw: Group: Tools offset=0x148e37 size=0x0x2e. 
vmw: Group: Tools Install offset=0x148e65 size=0x0x19. 
vmw: Group: GuestAppMonitor offset=0x148e7e size=0x0xc3. 
vmw: Group: MKSVMX offset=0x148f41 size=0x0x4cc. 
vmw: Group: ToolsDeployPkg offset=0x14940d size=0x0x2. 
vmw: Group: DMA offset=0x14940f size=0x0x3a4. 
vmw: Group: BackdoorAPM offset=0x1497b3 size=0x0xd. 
vmw: Group: CMOS offset=0x1497c0 size=0x0x27c. 
vmw: Group: FlashRam offset=0x149a3c size=0x0x42058. 
vmw: Group: smram offset=0x18ba94 size=0x0x2801b. 
vmw: Group: A20 offset=0x1b3aaf size=0x0x10. 
vmw: Group: backdoorAbsMouse offset=0x1b3abf size=0x0x13. 
vmw: Group: Keyboard offset=0x1b3ad2 size=0x0x5ef. 
vmw: Group: SIO offset=0x1b40c1 size=0x0x86. 
vmw: Group: monitorLate offset=0x1b4147 size=0x0x2. 
vmw: Group: MemoryHotplug offset=0x1b4149 size=0x0x9fd4. 
vmw: Group: devices offset=0x1be11d size=0x0x3f. 
vmw: Group: configdbFT offset=0x1be15c size=0x0x2. 
vmw: Group: FeatureCompat offset=0x1be15e size=0x0xde3. 
vmw: Group: NamespaceMgr offset=0x1bef41 size=0x0x2. 
vmw: Memory dump is not part of this vmss file. 
vmw: Try to locate the companion vmem file ... 
vmw: vmem file: /home/mfusion/vmem_vmss_jan26/gt-mfusion2-gmt-612746ca.vmem

readmem: read_vmware_vmss() 
crash: /dev/tty: No such device or address 
NOTE: stdin: not a tty

crash: pv_init_ops exists: ARCH_PVOPS 
gdb /home/mfusion/vmem_vmss_jan26/usr/lib/debug/usr/lib/modules/4.14.11-coreos/vmlinux 
GNU gdb (GDB) 7.6 
Copyright (C) 2013 Free Software Foundation, Inc. 
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> 
This is free software: you are free to change and redistribute it. 
There is NO WARRANTY, to the extent permitted by law. Type "show copying" 
and "show warranty" for details. 
This GDB was configured as "x86_64-unknown-linux-gnu"... 
GETBUF(280 -> 0) 
GETBUF(1500 -> 1) 
FREEBUF(1) 
FREEBUF(0) 
<readmem: ffffffff82042858, KVADDR, "page_offset_base", 8, (FOE), d24568> 
<read_vmware_vmss: addr: ffffffff82042858 paddr: 2042858 cnt: 8> 
<readmem: ffffffff81c18500, KVADDR, "kernel_config_data", 32768, (ROE), 25df690> 
<read_vmware_vmss: addr: ffffffff81c18500 paddr: 1c18500 cnt: 2816> 
<read_vmware_vmss: addr: ffffffff81c19000 paddr: 1c19000 cnt: 4096> 
<read_vmware_vmss: addr: ffffffff81c1a000 paddr: 1c1a000 cnt: 4096> 
<read_vmware_vmss: addr: ffffffff81c1b000 paddr: 1c1b000 cnt: 4096> 
<read_vmware_vmss: addr: ffffffff81c1c000 paddr: 1c1c000 cnt: 4096> 
<read_vmware_vmss: addr: ffffffff81c1d000 paddr: 1c1d000 cnt: 4096> 
<read_vmware_vmss: addr: ffffffff81c1e000 paddr: 1c1e000 cnt: 4096> 
<read_vmware_vmss: addr: ffffffff81c1f000 paddr: 1c1f000 cnt: 4096> 
<read_vmware_vmss: addr: ffffffff81c20000 paddr: 1c20000 cnt: 1280> 
WARNING: could not find MAGIC_START! 
GETBUF(280 -> 0) 
FREEBUF(0) 
GETBUF(64 -> 0) 
<readmem: ffffffff82126300, KVADDR, "possible", 64, (ROE), f64640> 
<read_vmware_vmss: addr: ffffffff82126300 paddr: 2126300 cnt: 64> 
cpu_possible_mask: cpus: 4 6 8 9 12 13 14 15 18 20 21 23 27 28 29 31 32 33 36 37 39 44 45 47 48 49 50 51 54 55 57 58 62 64 65 67 68 69 71 72 73 74 77 80 81 83 84 85 88 89 92 101 102 105 107 108 109 111 112 120 122 124 125 126 128 133 137 138 139 140 141 144 146 148 149 150 151 152 153 154 155 156 157 159 161 163 165 166 167 170 175 176 177 178 179 180 183 184 185 186 187 191 192 194 195 196 198 201 205 207 208 209 212 217 219 221 225 227 228 230 232 233 238 240 242 244 246 251 252 253 255 256 257 258 262 266 267 269 271 274 278 280 281 283 286 287 290 293 294 295 296 297 298 299 300 301 302 310 312 313 314 315 316 317 318 319 320 321 322 325 327 328 329 330 331 335 336 338 339 340 342 345 351 353 354 355 356 357 358 359 360 361 362 364 365 366 367 368 370 372 373 375 377 378 380 381 383 384 389 391 392 393 394 395 396 397 398 404 405 406 409 410 413 414 416 417 418 425 427 428 429 430 431 432 433 437 440 444 445 446 447 448 449 451 453 454 457 459 460 461 464 467 468 473 474 475 476 477 478 480 482 483 486 488 489 490 491 492 493 495 496 500 501 502 503 509 510 511 
<readmem: ffffffff82126280, KVADDR, "present", 64, (ROE), f64640> 
<read_vmware_vmss: addr: ffffffff82126280 paddr: 2126280 cnt: 64> 
cpu_present_mask: cpus: 1 3 5 10 11 12 15 16 17 18 19 20 21 23 24 26 29 30 32 33 34 35 36 41 43 44 50 56 58 60 63 67 68 69 71 72 73 76 77 78 79 80 81 86 90 91 93 96 97 99 104 105 106 108 111 114 117 118 119 121 123 124 127 129 131 133 135 137 138 140 143 144 145 149 152 155 156 158 162 164 165 166 167 169 172 173 174 175 178 180 183 189 191 192 193 194 196 197 199 201 203 206 210 211 212 213 215 216 218 219 222 224 225 226 227 228 230 231 232 235 238 240 244 245 246 250 251 253 255 256 258 259 263 264 267 268 271 272 274 275 276 278 280 282 284 285 287 289 293 294 295 297 299 300 301 303 305 308 310 312 316 317 318 320 322 323 324 326 328 329 331 332 334 335 340 342 343 344 345 346 349 350 351 356 358 364 366 368 369 370 371 372 377 379 381 385 386 387 394 397 400 401 404 406 407 409 412 413 414 415 416 417 419 420 421 422 423 425 427 429 430 431 433 439 440 444 447 449 452 454 455 456 459 460 462 463 465 467 468 469 470 472 476 478 480 482 483 484 485 486 488 489 490 491 492 494 495 496 501 504 506 508 509 510 511 
<readmem: ffffffff821262c0, KVADDR, "online", 64, (ROE), f64640> 
<read_vmware_vmss: addr: ffffffff821262c0 paddr: 21262c0 cnt: 64> 
cpu_online_mask: cpus: 0 3 4 8 10 11 12 13 15 17 21 22 27 28 29 32 33 35 44 45 46 48 49 51 52 53 54 57 58 59 62 63 65 66 67 69 72 74 75 86 87 89 90 91 96 97 99 100 101 106 107 110 111 113 115 116 117 122 123 125 128 129 130 134 135 136 142 143 145 147 149 150 153 156 157 160 161 163 164 166 167 168 173 176 179 180 184 187 189 191 192 193 198 199 201 204 205 207 208 209 212 214 215 216 217 218 221 222 224 227 228 234 235 236 239 241 242 244 245 248 250 252 253 255 256 257 262 263 265 266 267 268 271 273 275 276 277 278 279 280 288 289 291 293 295 296 297 300 304 305 306 308 310 312 313 317 318 320 325 326 327 328 329 330 331 332 333 337 338 339 342 344 346 348 349 350 352 355 356 361 368 369 375 380 381 382 383 385 387 389 390 391 394 395 397 398 399 400 401 403 405 406 408 409 410 412 415 416 417 418 422 424 427 429 430 432 434 436 438 441 443 444 451 452 456 460 462 464 466 469 473 474 476 479 480 484 487 488 489 494 498 499 500 503 504 506 509 510 
<readmem: ffffffff82126240, KVADDR, "active", 64, (ROE), f64640> 
<read_vmware_vmss: addr: ffffffff82126240 paddr: 2126240 cnt: 64> 
cpu_active_mask: cpus: 0 1 3 4 5 8 12 13 14 15 16 19 21 23 25 27 29 37 43 45 48 51 54 55 56 57 58 59 60 61 62 63 66 67 68 70 73 75 76 78 80 81 84 86 92 94 95 96 98 99 100 103 104 105 109 110 111 114 115 122 124 126 127 128 130 134 136 137 141 142 144 146 150 152 154 158 159 161 164 168 169 170 172 174 177 178 180 181 183 189 192 195 198 202 204 207 208 212 213 214 215 216 217 222 225 227 228 229 230 233 234 235 238 239 240 242 244 247 248 250 253 255 256 258 260 267 268 270 273 274 275 276 279 280 282 286 287 294 296 300 302 303 305 308 310 311 312 313 314 315 316 317 319 320 323 325 328 330 331 333 336 337 340 341 342 344 348 349 350 351 352 353 354 355 359 363 364 366 368 370 373 374 375 379 380 382 383 385 387 388 391 397 398 400 401 402 403 408 409 410 412 414 416 417 418 420 423 430 431 439 445 446 448 449 450 451 458 459 461 463 468 469 470 471 472 474 475 477 481 483 484 486 488 490 495 496 497 500 501 503 504 505 509 
FREEBUF(0) 
<readmem: ffffffff82031aa0, KVADDR, "pv_init_ops", 8, (ROE), 7fffa1149090> 
<read_vmware_vmss: addr: ffffffff82031aa0 paddr: 2031aa0 cnt: 8> 
GETBUF(280 -> 0) 
FREEBUF(0) 
GETBUF(280 -> 0) 
FREEBUF(0) 
<readmem: ffffffff84710860, KVADDR, "shadow_timekeeper xtime_sec", 8, (ROE), 7fffa1149030> 
<read_vmware_vmss: addr: ffffffff84710860 paddr: 4710860 cnt: 8> 
xtime timespec.tv_sec: 54d151d0619456fc: (null) 
<readmem: ffffffff82012304, KVADDR, "init_uts_ns", 390, (ROE), d0a7fc> 
<read_vmware_vmss: addr: ffffffff82012304 paddr: 2012304 cnt: 390> 
utsname: 
sysname: (not printable) 
nodename: (not printable) 
release: (not printable) 
version: (not printable) 
machine: (not printable) 
domainname: (not printable) 
crash: cannot determine base kernel version 
<readmem: ffffffff81c00100, KVADDR, "accessible check", 8, (ROE|Q), 7fffa1146390> 
<read_vmware_vmss: addr: ffffffff81c00100 paddr: 1c00100 cnt: 8> 
<readmem: ffffffff81c00100, KVADDR, "read_string characters", 1499, (ROE|Q), 7fffa11466f0> 
<read_vmware_vmss: addr: ffffffff81c00100 paddr: 1c00100 cnt: 1499> 
linux_banner: 
-ش????kB??C???Ã͞}&k?Xb?8/?ν?fF??&v;?Š???? ?? 
crash: /home/user/vmem_vmss_jan26/usr/lib/modules/4.14.11-coreos/build/System.map and /home/mfusion/vmem_vmss_jan26/gt-Server2-gmt-612746ca.vmss do not match!

Usage:

crash [OPTION]... NAMELIST MEMORY-IMAGE[@ADDRESS] (dumpfile form) 
crash [OPTION]... [NAMELIST] (live system form)

Enter "crash -h" for details. 
[root@gt-Server2-gmt user]# 

Please let me know if you need any further information.
Will get back to you after checking KASLR and phys_base.

Thank you,
Eshak

On Tue, Feb 6, 2018 at 7:26 AM, Dave Anderson <anderson@redhat.com> wrote:


----- Original Message -----
>
>
> ----- Original Message -----
> > Hello,
> >
> > We have a CoreOS VM(46 vCPU, 60GB RAM) freeze issue and hoping to find out
> > what is going on in it at the time of freeze. When the VM froze, we have no
> > access to it via ssh and ping works sometimes but not always. So, we
> > suspended the VM which created vmem and vmss files.
> >
> > Since this is a CoreOS VM, I have used toolbox to install and run crash.
> > When trying to read these files using crash utility, I'm getting the below
> > message:
> >
> >
> >
> > <read_vmware_vmss: addr: ffffffff81c00100 paddr: 1c00100 cnt: 8>
> >
> > <readmem: ffffffff81c00100, KVADDR, "read_string characters", 1499,
> > (ROE|Q),
> > 7ffcf595cd70>
> >
> > <read_vmware_vmss: addr: ffffffff81c00100 paddr: 1c00100 cnt: 1499>
> >
> > linux_banner:
> >
> > -ش????kB??C???Ã͞}&k?Xb?8/?ν?fF??&v;?Š???? ??
>
> It would have been helpful to see the full crash -d# log, but I'm presuming
> that the utsname data and the cpus_[possible/present/online/active]_mask
> output
> that gets displayed just before the linux_banner output are also nonsensical?
>
> Typically this kind of problem is because phys_base cannot be determined,
> or if KASLR is enabled, the KASLR offset cannot be determined.  Those two
> items are encoded into the dumpfile header for kdump dumpfiles, but there
> is no such information in a vmms dumpfile header.
>
> Can you run crash live on the machine?  You can see whether the phys_base
> and KASLR offset are non-zero on the live system by entering:
>
>   crash> help -m | grep phys_base
>                   phys_base: 129800000
>   crash> help -k | grep relocate
>         relocate: ffffffffcf400000  (KASLR offset: 30c00000 / 780MB)
>   crash>
>
> If relocate is 0 (KASLR not enabled), then the phys_base value can
> be applied to your vmcore by entering, for example, "--machdep
> phys_base=780m"
> on the crash command line (using your phys_base).

Sorry, my mistake -- it would be "--machdep phys_base=129800000".