devices: IOAPIC: ignore interrupt polarity

Interrupt polarity is ignored by kvm since 3.15, and the irqfd interface
does not support polarity. We should not consider polarity either.

BUG=chromium:908689
TEST=Unit tests in file. Integration testing is blocked on rest of
split-irqchip being implemented.

Change-Id: Ibae23b81274f867bbf56009854611628dbb4c154
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/1945793
Commit-Queue: Zhuocheng Ding <zhuocheng.ding@intel.corp-partner.google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Reviewed-by: Stephen Barber <smbarber@chromium.org>

1 files changed, 2 insertions, 7 deletions

diff --git a/devices/src/ioapic.rs b/devices/src/ioapic.rs
index 5f8270c..6f8e358 100644
--- a/devices/src/ioapic.rs
+++ b/devices/src/ioapic.rs
@@ -186,14 +186,9 @@ impl Ioapic {
 
     pub fn service_irq(&mut self, irq: usize, level: bool) -> bool {
         let entry = &mut self.redirect_table[irq];
-        let line_status = if entry.get_polarity() == 1 {
-            !level
-        } else {
-            level
-        };
 
         // De-assert the interrupt.
-        if !line_status {
+        if !level {
             self.current_interrupt_level_bitmap &= !(1 << irq);
             return true;
         }
@@ -226,7 +221,7 @@ impl Ioapic {
         // TODO(mutexlox): Pulse (assert and deassert) interrupt
         let injected = true;
 
-        if entry.get_trigger_mode() == TriggerMode::Level && line_status && injected {
+        if entry.get_trigger_mode() == TriggerMode::Level && level && injected {
             entry.set_remote_irr(true);
         } else if irq == RTC_IRQ && injected {
             self.rtc_remote_irr = true;