Re: [Patch]: write_kmem above high_memory

[Tigran Aivazian]

On Tue, 4 Jan 2000, Manfred Spraul wrote:
> set_fs(KERNEL_DS) + get_user()/__get_user()?
> 
> BUT: that's dangerous, because we might read from the mmap'ed io space
> of a hardware device.

Also, vwrite() could be used from within a system call emulation for some
other personality where the passed addresses would be kernel ones (i.e.
emulator would have done set_fs(get_ds()) before the call).

> The current show_registers() [arch/i386/kernel/traps.c] code has the
> same problem: on SMP, it causes a hard lock-up if the EIP value got
> corrupted.
> Linus rejected my first patch [walks the page tables], and I'm waiting
> for an answer on my new patch [__get_user()].

Your patch to show_registers() or your patch to read_kmem/vread()?

Regards,
Tigran.