Re: [GIT PULL] x86: unify sys_iopl

From: Ingo Molnar
Date: Tue Oct 13 2009 - 06:32:27 EST



* Jeremy Fitzhardinge <jeremy@xxxxxxxx> wrote:

> Hi Ingo,
>
> The x86-64 implementation of iopl was buggy because it never ended up
> calling set_iopl_mask(). This had no effect on native sys_iopl
> (because set_iopl_mask is normally no-op on 64-bit), but it ended up
> never calling the pvop, which caused iopl to have no effect on 64-bit
> Xen guests.
>
> The two functions are needlessly different anyway. This patch just
> unifies them into a single function which is mostly derived from the
> 32-bit version.
>
> Thanks,
> J
>
> The following changes since commit c44c9ec0f38b939b3200436e3aa95c1aa83c41c7:
> Jeremy Fitzhardinge (1):
> x86: split NX setup into separate file to limit unstack-protected code
>
> are available in the git repository at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git bugfix
>
> Jeremy Fitzhardinge (1):
> x86: unify sys_iopl
>
> arch/x86/include/asm/syscalls.h | 8 +++-----
> arch/x86/kernel/ioport.c | 11 ++---------
> 2 files changed, 5 insertions(+), 14 deletions(-)

Pulled, thanks a lot Jeremy!

It's in tip:x86/paravirt right now. I'm uneasy about pushing this into
.32 - we had this status quo forever. Peter, Thomas, what do you think?

Ingo
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