OK. poking around I found some tips from others who bricked their LInux. Below is the result I get when I reset the Yun while connected via USB serial. Looks like something is corrupt but I lack the knowledge to interpret and establish next steps.
U-Boot 1.1.4-gd995931a-dirty (Aug 7 2013 - 16:16:04)
Arduino Yun (ar9331) U-boot
DRAM: 64 MB
Top of RAM usable for U-Boot at: 84000000
Reserving 142k for U-Boot at: 83fdc000
Reserving 192k for malloc() at: 83fac000
Reserving 44 Bytes for Board Info at: 83fabfd4
Reserving 36 Bytes for Global Data at: 83fabfb0
Reserving 128 forbootparas() a: 838bfb
Stak Poiter a: 838bf9
Now running in RAM - U-Boot at: 83fdc000
Flash Manuf Id 0xef, DeviceId0 0x40, DeviceId1 0x18
flash size 16777216, sector count 256
Flash 16MB
Using default environment
In: serial
Out: serial
Err: serial
Net: ag7240_enet_initialize...
No valid address in Flash. Using fixed address
No valid address in Flash. Using fixed address
: cfg1 0x5 cfg2 0x7114
eth0: 00:03:7f:09:0b:ad
eth0 up
: cfg1 0xf cfg2 0x7214
eth1: 00:03:7f:09:0b:ad
athrs26_reg_init_lan
ATHRS26: resetting s26
ATHRS26: s26 reset done
eth1 up
eth0, eth1
Hit any key to stop autoboot: 4 3 2 1 0
## Booting image at 9fea0000 ...
Image Name: MIPS OpenWrt Linux-3.3.8
Created: 2014-08-07 10:42:20 UTC
Image Type: MIPS Linux Kernel Image (lzma compressed)
Data Size: 1185655 Bytes = 1.1 MB
Load Address: 80060000
Entry Point: 80060000
Verifying Checksum at 0x9fea0040 ...OK
Uncompressing Kernel Image ... OK
No initrd
## Transferring control to Linux (at address 80060000) ...
## Giving linux memsize in bytes, 67108864
Starting kernel ...
[ 0.000000] Linux version 3.3.8 (jenkins@jenkins) (gcc version 4.6.3 20120201 (prerelease) (Linaro GCC 4.6-2012.02) ) #1 Thu Aug 7 12:39:46 CEST 2014
[ 0.000000] bootconsole [early0] enabled
[ 0.000000] CPU revision is: 00019374 (MIPS 24Kc)
[ 0.000000] SoC: Atheros AR9330 rev 1
[ 0.00000]Clocs: CP:400.00MHz DDR400.00MH, AHB200.00MH, Ref25.00MHz
.00000] Dtermied pysica RAMmap:
[ .00000] memor: 0400000@ 0000000(usabe)
[ 0.000000] Initrd not found orempty- disblin inird
[ 0.0000] Zoe PF rangs:
[ 000000] ormal 0x000000 ->0x0004000
[ 0.00000] ovabl zon star PFNfor ech noe
000000] Ealy mmory FN rages
[ .00000] 0:0x0000000-> 0x000400
[ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 16256
[ 0.000000] Kernel command line: board=Yun console=ttyATH0,250000 mtdparts=spi0.0:256k(u-boot)ro,64k(u-boot-env)ro,14656k(rootfs),1280k(kernel),64k(nvram),64k(art),15936k@0x50000(firmware) rootfstype=squashfs,jffs2 noinitrd
[ 0.000000] PIDhashtableentris: 25 (oder: 2, 104 byts)
[ .00000] Dntry achehashtableentris: 892 (rder:3, 3268 byes)
[ 0.00000] Iode-achehash able ntrie: 406 (oder: , 1634 btes)
[ 0.000000] Primary instruction cache 64kB, VIPT, 4-way, linesize 32 bytes.
[ 0.000000] Primary data cache 32kB, 4-way, VIPT, cache aliases, linesize 32 bytes
[ 0.000000] Writing ErrCtl register=0000000
[ 0.0000] Reaback rrCt regiter0000000
[ 0.000000] Memory: 60936k/65536k available (2565k kernel code, 4600k reserved, 650k data, 180k init, 0k highmem)
[ 0.000000] SLUB: Genslabs=9, HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[ 0.000000] NR_IRQS:51
[ 0.000000] Calibrating delay loop... 265.42 BogoMIPS (lpj=1327104)
[ 0.080000] pid_max: default: 32768 minimum: 301
[ 0.080000] Mount-cache hash table entries: 512
[ 0.080000] NET: Registered protocol family 16
[ 0.090000] gpiochip_add: registered GPIOs 0 to 29 on device: ath79
[ 0.090000] MIPS: machine is Arduino Yun
[ 0.530000] Setting DogStick2 GPIO
[ 0.550000] bio: create slab <bio-0> at 0
[ 0.550000] SCSI subsystem initialized
[ 0.560000] usbcore: registered new interface driver usbfs
[ 0.560000] usbcore: registered new interface driver hub
[ 0.560000] usbcore: registered new device driver usb
[ 0.570000] Switching to clocksource MIPS
[ 0.570000] NET: Registered protocol family 2
[ 0.570000] IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
[ 0.580000] TCP established hash table entries: 2048 (order: 2, 16384 bytes)
[ 0.580000] TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.580000] TCP: Hash tables configured (established 048 bnd 248)
[ .58000] TP reo regstere
[ 0.8000] UDPhash able ntres: 26 (orer: 0 409 byts)
[ 0.90000 UD-Litehash able ntris: 26 (orer: 0 4096byts)
[ 059000] NET Reisterd proocol amil 1
[ 0.610000] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[ 0.610000] JFFS2 version 2.2 (NAND) (SUMMARY) (LZMA) (RTIME) (CMODE_PRIORITY) (c) 2001-2006 Red Hat, Inc.
[ 0.620000] msgmni has been set to 119
[ 0.620000] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 254)
[ 0.620000] io scheduler noop registered
[ 0.630000] io scheduler deadline registered (default)
[ 0.630000] Serial: 8250/16550 driver, 16 ports, IRQ sharing enabled
[ 0.640000] ar933x-uart: ttyATH0 at MMIO 0x18020000 (irq = 11) i{ a AR933X UART
[ 0.640000] console [ttyATH0] enabled, bootconsole disabled
[ 0.640000] console [ttyATH0] enabled, bootconsole disabled
[ 0.650000] m25p80 spi0.0: found w25q128, expected m25p80
[ 0.650000] m25p80 spi0.0: w25q128 (16384 Kbytes)
[ 0.650000] 7 cmdlinepart partitions found on MTD device spi0.0
[ 0.660000] Creating 7 MTD partitions on "spi0.0":
[ 0.660000] 0x000000000000-0x000000040000 : "u-boot"
[ 0.660000] 0x000000040000-0x000000050000 : "u-boot-env"
[ 0.670000] 0x000000050000-0x000000ea0000 : "rootfs"
[ 0.670000] mtd: partition "rootfs" set to be root filesystem
[ 0.670000] mtd: partition "rootfs_data" created automatically, ofs=7B0000, len=6F0000
[ 0.680000] 0x0000007b0000-0x000000ea0000 : "rootfs_data"
[ 0.680000] 0x000000ea0000-0x000000fe0000 : "kernel"
[ 0.680000] 0x000000fe0000-0x000000ff0000 : "nvram"
[ 0.690000] 0x000000ff0000-0x000001000000 : "art"
[ 0.690000] 0x000000050000-0x000000fe0000 : "firmware"
[ 0.710000] ag71xx_mdio: probed
[ 0.720000] eth0: Atheros AG71xx at 0xba000000, irq 5
[ 1.270000] eth0: Found an AR7240/AR9330 built-in switch
[ 2.300000] eth1: Atheros AG71xx at 0xb9000000, irq 4
[ 2.850000] ag71xx ag71xx.0: eth1: connected to PHY at ag71xx-mdio.1:04 [uid=004dd041, driver=Generic PHY]
[ 2.850000] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[ 2.850000] ehci-platform ehci-platform: Generic Platform EHCI Controller
[ 2.860000] ehci-platform ehci-platform: new USB bus registered, assigned us nmber
[ 2.890000] ehci-platform ehci-platform: irq 3, io mem 0x1b000000
[ 2.910000] ehci-platform ehci-platform: USB 2.0 started, EHCI 1.00
[ 2.910000] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
[ 2.910000] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 2.910000] usb usb1: Product: Generic Platform EHCI Controller
[ 2.920000] usb usb1: Manufacturer:Linux3.3.8ehci_cd
.92000] us usb1 SeialNmber:ehci-latfom
[ 2.920000] hub 1-0:1.0: USB hub found
[ 2.920000] hub 1-0:10: 1 ort dtecte
[ 2.30000 Initaliing UB Mas Storge drver..
[ 2.30000 usbore:regisered ew inerfce drver ub-strage
[ 2.93000] SB Mas Stragesuppot regsterd.
[ 2.93000] inut:gpiokeys-olledas /evics/plaform/pio-kys-plledinputinput
[ 2.940000] sdhci: Secure Digital Host Controller Interface driver
[ 2.94000] sdci: Cpyriht(c)Piere Ossan
294000] uscore:regiterednew nterfce diverushc
[ 2.94000] CP cuic reisteed
[ 295000] NE: Regsterd proocol amil 17
.95000] Bidgefirewllingregitere
[ 2.90000]8021: 8021Q VLN Suport 1.8
[ 2.960000] VFS: Mounted root (squashfs filesystem) readonly on device 31:2.
[ 2.960000] Freeing unused kernel memory: 180k freed
[ 3.290000] usb 1-1: new high-speed USB device number 2 using ehci-platform
[ 3.480000] usb 1-1: New USB device found, idVendor=058f, idProduct=6254
[ 3.480000] usb 1-1: New USB device strings: Mfr=0, Product=1, SerialNumber=0
[ 3.490000] usb 1-1: Product: USB2.0Hub
[ 3.550000] hub 1-1:1.0: USB hub found
[ 3.550000] hub 1-1:1.0: 4 ports detected
[ 3.610000] SQUASHFS error: xz_dec_run error, data probably corrupt
[ 3.610000] SQUASHFS error: squashfs_read_data failed to read block 0x456ae
[ 3.610000] SQUASHFS error: Unable to read data cache entry [456ae]
[ 3.620000] SQUASHFS error: Unable to read page, block 456ae, size 1516c
[ 3.620000] SQUASHFS error: Unable o red dat cace enty [46ae]
[ 3.62000] SUASHS errr: Uable o rad pae, blck 46ae, ize 516c
[ 3.63000] QUASHS errr: Uable o red dat cace enty [46ae]
[ .63000] SUASHS errr: Uableto red pae, blck 46ae, ize 516c
[ .63000] SUASHS errr: Unble o red dat cach enty [45ae]
[ .63000] SUASFS eror: Uable o red pae, blck 45ae, ize 516c
[ .64000] SUASHS errr: Unble o red dat cach entr [45ae]
[ 3.64000] SUASFS eror: Uable o red pae, blck 45ae, sze 516c
/bin/h: '/ib/lbc.s.0' i not n ELFfil
/bin/sh: can't load library 'libc.so.0'
[ 3.760000] Kernel panic - not syncing: Attempted to kill init!