Re: crash in entry.S restore_all, 2.6.12-rc2, x86, PAGEALLOC

Stas Sergeev
2005-04-05T19:48:11Z

Hi Linus,

Linus Torvalds wrote:
> This one can pass through vm86 mode stuff without the high-16-bit fixup,
> as far as I can tell.
Yes, but according to Petr, vm86 is not
affected by the bug at all. I did some
rough tests in the past that seem to
confirm that. Also, in any case, the
dependance of vm86 code on the higher word
of %esp would be very, very obscure.

> So I'd actually prefer to get that mystery explained..
IIRC if the interrupt doesn't do the CPL
switch, the interrupt gate doesn't save
the stack, and so there may not be the
full "struct pt_regs" when the kernel
thread is interrupted.
Does this sound any realistic?

So while it would be excellent to hear
that my patch was not guilty at all, I
think it is not the case.