Re: [PATCH] PCI: vgaarb: Remove stale "not implemented" notes from docs

[Christian Melendez Nuñez]

> [Severity: Medium]
> Is the "unlock all" command fully implemented and working as expected?
>
> If the user holds only one type of lock, wouldn't this fail with -EINVAL
> instead of unlocking the resources? Should the TODO disclaimer remain
> until this logic is fixed?

This is correct.  "unlock all" sets both VGA_RSRC_LEGACY_IO and
VGA_RSRC_LEGACY_MEM unconditionally:

    if (strncmp(curr_pos, "all", 3) == 0)
        io_state = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;

but "lock" allows acquiring them independently via vga_str_to_iostate(),
so a caller holding only one of them hits

    if (io_state & VGA_RSRC_LEGACY_MEM && uc->mem_cnt == 0) {
        ret_val = -EINVAL;
        goto done;
    }

and returns -EINVAL without releasing the lock it does hold. So "release
all locks on target held by this user" is not accurate unless both are
held, and the caveat should stay.

I'll wait for further review before sending a v2.

Thanks,
Christian