ACPI: avoid irqrouter_resume might_sleep oops on resume from S4
__might_sleep+0x8e/0x93
acpi_os_wait_semaphore+0x50/0xa3
acpi_ut_acquire_mutex+0x28/0x6a
acpi_ns_get_node+0x46/0x88
acpi_ns_evaluate+0x2d/0xfc
acpi_rs_set_srs_method_data+0xc5/0xe1
acpi_set_current_resources+0x31/0x3f
acpi_pci_link_set+0xfc/0x1a5
irqrouter_resume+0x48/0x5f
and
__might_sleep+0x8e/0x93
kmem_cache_alloc+0x2a/0x8f
acpi_evaluate_integer+0x32/0x96
acpi_bus_get_status+0x30/0x84
acpi_pci_link_set+0x12a/0x1a5
irqrouter_resume+0x48/0x5f
http://bugzilla.kernel.org/show_bug.cgi?id=6810
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index b7d1514..507f051 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -746,6 +746,16 @@
ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n",
handle, units, timeout));
+ /*
+ * This can be called during resume with interrupts off.
+ * Like boot-time, we should be single threaded and will
+ * always get the lock if we try -- timeout or not.
+ * If this doesn't succeed, then we will oops courtesy of
+ * might_sleep() in down().
+ */
+ if (!down_trylock(sem))
+ return AE_OK;
+
switch (timeout) {
/*
* No Wait:
diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index f48227f..d0d84c4 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -262,7 +262,7 @@
if (!data)
return AE_BAD_PARAMETER;
- element = kmalloc(sizeof(union acpi_object), GFP_KERNEL);
+ element = kmalloc(sizeof(union acpi_object), irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
if (!element)
return AE_NO_MEMORY;
