On Fri, Jul 31, 2015 at 9:50 AM, Ingo Molnar <mi...@kernel.org> wrote: > > * Brian Gerst <brge...@gmail.com> wrote: > >> On Fri, Jul 31, 2015 at 4:57 AM, Ingo Molnar <mi...@kernel.org> wrote: >> > >> > * Brian Gerst <brge...@gmail.com> wrote: >> > >> >> Allow disabling hardware interrupt support for vm86. >> >> >> >> Signed-off-by: Brian Gerst <brge...@gmail.com> >> >> --- >> >> arch/x86/Kconfig | 8 ++++++++ >> >> arch/x86/include/asm/irq_vectors.h | 10 ---------- >> >> arch/x86/include/asm/vm86.h | 20 ++++++++++++++++++-- >> >> arch/x86/kernel/vm86_32.c | 12 ++++++++++-- >> >> 4 files changed, 36 insertions(+), 14 deletions(-) >> >> >> >> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig >> >> index cbd2d62..7c7ec31 100644 >> >> --- a/arch/x86/Kconfig >> >> +++ b/arch/x86/Kconfig >> >> @@ -1067,6 +1067,14 @@ config VM86 >> >> bool >> >> default X86_LEGACY_VM86 >> >> >> >> +config VM86_INTERRUPTS >> >> + bool "Enable VM86 interrupt support" >> >> + default y >> >> + depends on VM86 >> >> + ---help--- >> >> + This option allows VM86 programs to request interrupts for >> >> + real mode hardware drivers. >> > >> > So I'm wondering what the justification for this is. People can disable >> > vm86 >> > already via CONFIG_X86_LEGACY_VM86. The extra config just uglifies the code >> > unnecessarily. >> > >> > Thanks, >> > >> > Ingo >> >> Disabling even less-used code that could have system stability impact. We've >> discouraged user-mode drivers for a very long time. Ironically, other than >> being configured through the vm86 syscall, there isn't really anything >> vm86-specific about it. All it does is register an IRQ handler that sends a >> signal to the task. > > So is this actually used by anything? Could we get away with disabling it, > just to > see whether anything cares?
My best guess would be some very old X11 drivers that needed interrupts to run the Video BIOS code. -- Brian Gerst -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
