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Hi, in my nvme driver, while creating the first i/o completion queue, it is failing with the status code 2 (Invalid Field in Command). I have double checked my commands and still can't figure out which cmd is invalid.

Here are my commands: https://pastebin.com/PYiL0WJA . I'm testing my driver on my real machine.

osdev199 wrote: ↑Mon Aug 05, 2024 6:55 amit is failing with the status code 2

What's the status code type?

status code type is 1 (Command Specific Status).

When the status code type is 1, status code 2 means "Maximum Queue Size Exceeded". Use CAP.MQES to choose a valid queue size.

Thank you. Before creating the i/o completion queue, I was reading the CAP register value. Accidentally I was doing `*addr = value` instead of `value = *addr`. I fixed this and I checked that the queue size i.e. 64 commands is valid. Still I'm getting the same error status.

What is the value of the CAP register?

Have you tried your driver in a virtual machine like QEMU?

CAP register value = 0x300a0103ff

I have tried running it on qemu too but launching qemu fails with "gtk initialization failed". I haven't been able to solve this issue yet!

How are you launching QEMU? How did you install QEMU?

I don't remember how did I install it. But as far as I know, when I added a password to my user account recently, this error began to appear. I'm already using `export DISPLAY=:0` in my .bashrc.

After asking on #qemu irc channel, I changed the DISPLAY value to 1 and it worked. Now in qemu, while resetting the controller during initialization, on clearing the CC.EN (bit #0) to 0, and writing it back, the new CC register value becomes 0 don't know why. However, the driver halts a bit later on the fatal error: CSTS.CFS is not 0!

I'm pasting the screenshot: https://drive.google.com/file/d/1Ay_8w7 ... sp=sharing

You need to choose reasonable values for CC.IOSQES and CC.IOCQES.

Please take a look at my code on this matter: https://github.com/MaciekLeks/bebok/blo ... e.zig#L905 . I have resolved the issue with sc=0x02 for sct=0x01. Now I'm struggling with sc=0x08. Good luck!

I don't like the virtual machine.

The others drivers I have checked have the same commands as mine and they are working fine.

If so, then why am I getting the error?

You can also resume the discussion in the issue that I have opened in the project:

https://github.com/robstat7/Raam/issues/4

mleks wrote: ↑Thu Aug 08, 2024 5:27 amsc=0x08

Invalid Interrupt Vector. You're using pin-based interrutps, so the interrupt vector needs to be 0. If you switch to MSI or MSI-X, the interrupt vector is the index in the list of MSI(-X) interrupts you've configured on the NVMe controller. The interrupt vector you need to use here is not the same as a CPU interrupt vector.

osdev199 wrote: ↑Thu Aug 08, 2024 7:00 amI don't like the virtual machine.

Does your code work in the virtual machine?