Re: [PATCH?] Crash in 2.4.17/ptrace
Manfred Spraul (manfred@colorfullife.com)
Mon, 28 Jan 2002 23:07:30 +0100
From: "Alan Cox" <alan@lxorguk.ukuu.org.uk>
> > For framebuffers addresses, there is no page structure, and then the
> > page reference count updates read/write to random memory.
>
> If it is a physical pci bus object why do we need to refcount it,
> surely "no page" is ok. Its just up to the driver not to do anything
> stupid and the core code to honour the pci/pci transfer quirks (or
> when faced with a hard one just say "no")
>
With multi-threaded apps, munmap() during O_DIRECT is possible. vma
structures don't contain a reference count.
For ptrace, taking the physical address from the PTE and ioremapping it
temporarily would work, but ...
--
Manfred
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/