Root Access

Michael Frank

05:39

@bob I accidentally click "Start new session"... Help?

Bob

06:16

@MichaelFrank ??

Michael Frank

06:58

@Bob In Firefox.

I did not click "Restore Session", now all my tabs are gone.

I know you are TabMaster, so please sensei, you're my only hope.

Bob

07:16

@MichaelFrank Open your profile folder via about:profiles and go to sessionstore-backups

copy everything there to another folder

and then look for the most recent biggest file

close firefox, rename file to previous.jsonlz4, and open firefox again

(and pull from backup folder if it fails, cause it'll clobber)

what you can get back depends on whether you (a) killed firefox [via task manager] asap (recovery might not be clobbered if within 30s), (b) didn't close firefox yet (previous might not be clobbered; iirc it writes on save though it might clear when you click start new?), or (c) you can only recover from the upgrade backup from the last (minor) release upgrade

also if you want a faster resp poke me on matrix next time, I actually get phone notifications there :P

djsmiley2k

guess who'[s back

back again

wow that's le suck

both the sudo thing, and firefox handling of restoring tabs after accidently not restoring them

in chrome i go 'history -> recently closed and they're all there (if all in one window it'd show "14 tabs"

Biswapriyo

07:46

What are those tools called which measure latency b/w a keypress and monitor? I saw some YouTube videos where people put the device on the display and measure the latency.

Bob

07:56

@Biswapriyo I like to call them cameras

(seriously though, you can emulate them with a phone camera. bonus points if you have a slow mo mode)

Burgi

morning

Bob

08:43

@djsmiley2k Actually, now that you mention it, I haven't been asked to restore/not-restore in quite a while.

djsmiley2k

o_O

Bob

I have mine set to always restore but if that's disabled the old session seems to still be accessible via the history menu *shrug*

djsmiley2k

as in it auto restores?

yeah

Does it only ask, if it's on auto, when it's crashed out?

because it maybe due to a tab causing the crash?

Bob

@djsmiley2k good point, that's the only place it still asks

Michael Frank

10:02

@Bob Yea... It seemed to be clobbered.

Oh well!

Ave

10:17

bleh, kernelcare.

that was 2 months ago

Ave

10:43

Blog bot

11:15

stackoverflow.blog/2019/10/15/…

bwDraco

tomshardware.com/news/… wat

NAND endurance is a problem, and here we have an industrial application managing to wear out flash.

djsmiley2k

11:47

@Blogbot "we got the chance to sit down with Prashanth Chandrasekar, Stack Overflow’s new CEO, to hear about how he got into computer science and his vision for this community and company." lul

@bwDraco lol

Why on earth are they logging to the firmware storage location

bwDraco

12:18

Yeah. Stuff that's expected to write lots of data over the life of the system should be on a separate, readily-replaceable board.

Also, use the correct type of storage! Choose high-endurance MLC flash if you need to write dozens of gigabytes to it every day for a decade or more.

This is a freaking automotive system. There is no reason to skimp on the storage.

If MLC isn't an option, at least properly size and overprovision the storage.

People just don't get that NAND endurance is not unlimited. I would expect folks working on automotive systems to know better.

And if it's nearly full, beware of write amplification (that's probably the thing they missed).

insideevs.com/news/376037/tesla-mcu-emmc-memory-issue

> 8 GB eMMC

What the fuck.

Why would anyone seriously believe that such a small flash memory chip could handle dozens of gigabytes of writes each day for a decade?

Also, that chip is almost full. Write amplification will kill it.

Totally idiotic.

djsmiley2k

12:41

@bwDraco developers are stupid in everything other than development. I'm not even joking here.

I have developers who don't understand networking, sysadmin, ops, or anything else. They just know code.

bwDraco

13:05

IMO the best way to cope with the limited endurance of flash memory in a complex industrial system is to treat it as a consumable. All storage will eventually fail, but flash memory has write endurance limits that must be accounted for.

Bob

@djsmiley2k :<

@bwDraco Meh.

Rotating logs are the poster child for flash-optimised filesystems that deal primarily with append writes.

Just configure the right buffer size and you have exactly zero write amp.

djsmiley2k

@Bob not all devs obv.

bwDraco

@Bob The infotainment software shares space with the logs. The system needs to do at least some wear-leveling so there will be a nonzero amount of write amplification.

That, too, is an idiotic decision.

You can't expect all logging to happen within a mere few hundred megabytes of space, repeatedly overwrite that limited area without any amount of wear leveling, and expect the flash to last long enough for an industrial application where it needs to operate at least a decade.

Bob

Ahem.

See: "flash-optimised filesystems".

bwDraco

True but I'm inclined to think they just used ext4 rather than something like F2FS. It's unlikely that the problem of NAND endurance even crossed the developers' minds.

Biswapriyo

17:03

Does there something happen in SU? I got rep. down with "user was removed". I also see this in other >10K rep. users' activity.

djsmiley2k

17:43

not just in SU.

djsmiley2k

19:27

mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm

bwDraco

nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn

djsmiley2k

lol

bertieb

20:01

o

salbeira

22:37

Anyone here that can tell me how I can delete a system file as Administrator in Windows10? It seems something with my pending.xml in my WinSxS file is wrong and even DISM can not fix it anymore so deleting is my final option before I wipe my C:\ and reinstall the shit

Burgi

have you tried from the cmd prompt?

salbeira

Yes even running the cmd or powershell as administrator gives me an "Access Denied" error

How dare Windows give root an access denied error ...

Burgi

tried stopping the services as well?

salbeira

That would require me to know what service is accessing it

Burgi

717

Q: Find out which process is locking a file or folder in Windows

How can I find out which process is locking a file or folder in Windows? For instance, when trying to delete a folder, Windows reports this: The action can't be completed because the folder is open in another program Happens the same with a file, but how do I find out what program or appli...

salbeira

22:40

stopping wuaserv did not work

+ Remove-Item .\pending.xml
+ ~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : PermissionDenied: (C:\WINDOWS\WinSxS\pending.xml:FileInfo) [Remove-Item], UnauthorizedAc
cessException
+ FullyQualifiedErrorId : RemoveFileSystemItemUnAuthorizedAccess,Microsoft.PowerShell.Commands.RemoveItemCommand

Burgi

and did you check resource monitor?

salbeira

What can I find there?

It seems the file is not locked by any process

Is there a difference in ownership from SYSTEM and an Administrator account?

Burgi

perhaps you should ask this question on the main site now?

salbeira

Well I rather have some interactive conversation while doing this rather than desperatly waiting for an answer on the main site

Especially as I want to go to bed soon and tell my mate to get over his installation medium again if I need to do a complete reinstall of my system

Michael Frank

22:56

psexec -s -i cmd.exe

can't be denied by SYSTEM if you are SYSTEM

salbeira

psexec could not be found

Michael Frank

Yea, it doesn't come with Windows by default: docs.microsoft.com/en-us/sysinternals/downloads/psexec

salbeira

Downloaded the PSTools, running it as above with -s -i sadly only opens a cmd as "Administrator" again and I still get a "access denied"

Michael Frank

run cmd as admin, then run psexec -s -i cmd.exe

then whoami

salbeira

nt-autorität\system

Michael Frank

23:08

Still no luck removing the file?

salbeira

Seems right but I still get an access denied

C:\Windows\WinSxS>del pending.xml
C:\Windows\WinSxS\pending.xml
Zugriff verweigert

C:\Windows\WinSxS>

(German here but whatever)

How hard can it be to freakin delete a file o.O

Michael Frank

You're not really supposed to be touching anything in WinSxS anyway.... that's why SYSTEM owns it.

salbeira

Well my problem is that Windows Update fails to upgrade my system to 1903 for a long time now and I want to get it done

It seems that something in the wusa.exe fails - getting logs or any information about WHAT fails was hard enough

Most guides recommend fixing the system with sfc /scannow

That fails because it says there are still system changes queued that should be resolved after a restart

problem is that nothing happens after a restart - ever

Using DISM to repair and remove all pending changes causes THAT command to also fail

THAT lead me to a solution to manually DELETE the pending.xml file

AND SOMEHOW I CANT DO IT tableflip

Michael Frank

Since you downloaded PSTools, try the Handle application to see if it will tell you what has pending.xml locked

salbeira

What name is it?

PsService?

Michael Frank

23:18

Should be in the PSTools zip, called Handle I think?

salbeira

Nope

Michael Frank

Oh sorry, it's here: docs.microsoft.com/en-us/sysinternals/downloads/handle

You could also use ProcessExplorer which you did get though.

ahh wait... maybe not.

It's all there on that site anyway.

salbeira

Is it .\handle.exe FilePath?

Michael Frank

I think so.

salbeira

Ah it is just a string to match output against

But no, handle pending.xml says No matching Handles found

the File is not opened by ANYTHING

It just refuses to be deletad

Upgrading to 1903 via the mediaCreationTool also does not work "directly"

Creating a separate USB installation on an USB drive will allow me to do a complete reinstall of windows does it?

Journeyman Geek

23:35

@salbeira yup

Actually I think I have the same issue

Been putting off doing a rebuild

salbeira

"Everything went to shit when I got my first Bluescreen in years while playing Sekiro" ...

in lieau of "Everything changed when the fire nation attacked"

Michael Frank

Did you try takeown /f pending.xml ?

salbeira

PS C:\Windows\WinSxS> takeown.exe /f pending.xml

ERFOLGREICH: Die Datei (oder der Ordner) "C:\Windows\WinSxS\pending.xml" gehört jetzt dem Benutzer "DESKTOP-F0N7VR7\Hauer".
PS C:\Windows\WinSxS> del .\pending.xml
del : Das Element C:\Windows\WinSxS\pending.xml kann nicht entfernt werden: Der Zugriff auf den Pfad "C:\Windows\WinSxS\pending.xml" wurde verweigert.
In Zeile:1 Zeichen:1
+ del .\pending.xml
+ ~~~~~~~~~~~~~~~~~
+ CategoryInfo : PermissionDenied: (C:\Windows\WinSxS\pending.xml:FileInfo) [Remove-Item], UnauthorizedAccessException

Michael Frank

as admin?

salbeira

I AM the Admin

Running powershell as administrator gives me that user

It is the only user on the system - me - and I am the administrator

well next to SYSTEM and some other default crap

Michael Frank

23:40

Yes, but you still have to tell Windows you want to act as the Admin.

salbeira

I did

I am running the powershell as administrator (right-click etc.)

Michael Frank

okay, now

cacls pending.xml /G :F

salbeira

What does that program do?

Michael Frank

modifies the ACL on a file

/G :F applies Full Control

salbeira

Command successfull, del still returns error

Do I need to change access rights on the directory or something?

Michael Frank

23:45

I'd say no, but either way it seems you might be heading towards a reinstall of Windows. :|

salbeira

OK just so I am prepared because ... well ... working with Arch Linux is WAY easier ...

When I finish creating the Windows 10 1903 installation medium on my USB flash drive and reboot my PC and make it boot from the USB drive

I will need that tool to reinstall Windows on my C:/ drive - that installation will propably wipe everything on C:/, correct? (I have the feeling under Linux simply replacing the C:\Windows directory with something that is fresh would WORK BETTER but hell if I know)

Right now I am running Windows 10 1803

All applications like video games I still have on C:/ should be moved to my different drives as they should (tm) be unharmed by a reinstall, correct?

Also backing up my home directory and simply copying all APPDATA from the old one to the new one should restore most settings of games and appliactions I use?

(Imagine it being 2010 and someone says "Installing and Administrating Arch Linux is easier than Windows")

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