x86, ioapic: Fix non atomic allocation with interrupts disabled
Impact: fix possible race
save_mask_IO_APIC_setup() was using non atomic memory allocation while getting
called with interrupts disabled. Fix this by splitting this into two different
function. Allocation part save_IO_APIC_setup() now happens before
disabling interrupts.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 699f8cf..85eb8e1 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1334,15 +1334,16 @@
return;
}
- local_irq_save(flags);
- mask_8259A();
-
- ret = save_mask_IO_APIC_setup();
+ ret = save_IO_APIC_setup();
if (ret) {
pr_info("Saving IO-APIC state failed: %d\n", ret);
goto end;
}
+ local_irq_save(flags);
+ mask_IO_APIC_setup();
+ mask_8259A();
+
ret = enable_intr_remapping(1);
if (ret && x2apic_preenabled) {
@@ -1367,10 +1368,10 @@
else
reinit_intr_remapped_IO_APIC(x2apic_preenabled);
-end:
unmask_8259A();
local_irq_restore(flags);
+end:
if (!ret) {
if (!x2apic_preenabled)
pr_info("Enabled x2apic and interrupt-remapping\n");