[Galaxy Y GT-S5360 and Duos 6102 Q&A, Help & Troubl] catwank:
I was wondering whenever I should post this in the "bricks" thread, I'm still not sure what the term "brick" means entirely but what I'm gathering is that it's usually when people try to flash sommat and mess it up, this isn't exactly the case for me, either way I believe this case to be special enough to deserve a separate thread, this is not your usual "guys help I installed custom rom x and am bootloop".

Context: A couple days ago I was in a call with someone and right after hanging up my phone froze completely, I had to reboot but then I was stuck at boot (bootloop), decided to try and wipe data (didn't really have anything important there) but I got an error when I tried to mount /data. After a while I decided to flash stock with odin, I was confident that would fix it, but it didn't, I was stuck at boot again, I went into recovery and tried to check if I could mount /data, but nope, none of that.

This is the error I get when I try to mount /data:

In stock recovery

-- Wiping data...
E:format_volume: rfs format failed on /dev/stl11

In CWM

-- Wiping data...
formatting /data...
Error mounting /data!
Skipping format...

Sometimes it'll just freeze at "Formatting /data...". By the way, the errors were the same before and after flashing stock.

Apparently something is wrong with my data partition, here is a list of things I have and have not tried so I eliminate the potentially not-useful replies, oh yes I can see them coming already:

I have tried:

-flashing stock with odin, it all works fine and I get PASS, only error I get is when my phone is installing CSC during recovery, but that's only because /data is unusable

-including PIT and bootloader

-yes, it's the correct PIT.

-yes, I checked re-partition.

-flashing PDA, MODEM, CSC, BL and PIT in every possible order

-trying mount /data (duh, that's the very issue)

-trying mount /data after flashing stock

-googling a lot

I have not tried:

-Any odin option other than the default ones and re-partition

I'm not really sure why this keeps happening after flashing PIT, as far as I know that's supposed to re-partition my phone, doesn't that mean it should wipe out anything in the partitions, thus getting a completely new /data partition?. I'm not an expert when it comes to android phones, I'm just comparing it to linux.

Is there a way to just REMOVE my /data partition and make a new one?, I believe that would fix the issue.

Some extra background, I have been using Hyperion 9 (not sure if it was 9?, I know it was the latest OFFICIAL hyperion rom though), I have bricked my phone in the past many times when I was a teenager (yes, this very same phone, I've had it for years), and also fixed it many times by flashing stock, at the end I got bored of it and stayed at stock, then about a year or two ago (I think?) I decided to find a custom rom + a kernel to save up on battery, I don't really remember what I did but I got Hyperion 9 and some kernel, haven't messed with my phone since.

Also, yes, I know this is a very old model, but if I can fix this phone I definitely will, I have my reasons.

EDIT: added more info

EDIT: I think one part sounded a bit rude, edited