Hi,
acpi_pci_link_set() allocates with GFP_ATOMIC. On resume from suspend,
this is called with interrupts off, otherwise GFP_KERNEL is safe.
On the other hand, when resuming from suspend with interrupts off, the
following callchain allocates with GFP_KERNEL, which is wrong:
acpi_pci_link_resume -> acpi_pci_link_set -> acpi_set_current_resources ->
acpi_rs_set_srs_method_data -> acpi_ut_create_internal_object_dbg ->
acpi_ut_allocate_object_desc_dbg -> acpi_os_acquire_object ->
kmem_cache_alloc(GFP_KERNEL) flag.
Resending patch, which didn't make it into -rc4, to fix both issues. The
patch is intentionally using irqs_disabled() and does not check in_resume
flag, as this is marked for removal (which is for example how
acpi_os_allocate() checks whether it should perform GFP_KERNEL or
GFP_ATOMIC allocation).
Signed-off-by: Jiri Kosina <[email protected]>
--- drivers/acpi/osl.c.orig 2006-07-15 21:00:43.000000000 +0200
+++ drivers/acpi/osl.c 2006-07-23 16:03:08.000000000 +0200
@@ -1141,7 +1141,13 @@ acpi_status acpi_os_release_object(acpi_
void *acpi_os_acquire_object(acpi_cache_t * cache)
{
- void *object = kmem_cache_alloc(cache, GFP_KERNEL);
+ void *object;
+
+ /* irqs could be disabled when resuming from suspend */
+ if (irqs_disabled())
+ object = kmem_cache_alloc(cache, GFP_ATOMIC);
+ else
+ object = kmem_cache_alloc(cache, GFP_KERNEL);
WARN_ON(!object);
return object;
}
--- drivers/acpi/pci_link.c.orig 2006-07-15 21:00:43.000000000 +0200
+++ drivers/acpi/pci_link.c 2006-07-23 16:01:42.000000000 +0200
@@ -318,7 +318,12 @@ static int acpi_pci_link_set(struct acpi
if (!link || !irq)
return_VALUE(-EINVAL);
- resource = kmalloc(sizeof(*resource) + 1, GFP_ATOMIC);
+ /* irqs could be disabled when resuming from suspend */
+ if (irqs_disabled())
+ resource = kmalloc(sizeof(*resource) + 1, GFP_ATOMIC);
+ else
+ resource = kmalloc(sizeof(*resource) + 1, GFP_KERNEL);
+
if (!resource)
return_VALUE(-ENOMEM);
--
JiKos.
On Mon, 7 Aug 2006 16:30:43 +0200 (CEST)
Jiri Kosina <[email protected]> wrote:
> acpi_pci_link_set() allocates with GFP_ATOMIC. On resume from suspend,
> this is called with interrupts off, otherwise GFP_KERNEL is safe.
>
> On the other hand, when resuming from suspend with interrupts off, the
> following callchain allocates with GFP_KERNEL, which is wrong:
>
> acpi_pci_link_resume -> acpi_pci_link_set -> acpi_set_current_resources ->
> acpi_rs_set_srs_method_data -> acpi_ut_create_internal_object_dbg ->
> acpi_ut_allocate_object_desc_dbg -> acpi_os_acquire_object ->
> kmem_cache_alloc(GFP_KERNEL) flag.
>
> Resending patch, which didn't make it into -rc4, to fix both issues. The
> patch is intentionally using irqs_disabled() and does not check in_resume
> flag, as this is marked for removal (which is for example how
> acpi_os_allocate() checks whether it should perform GFP_KERNEL or
> GFP_ATOMIC allocation).
acpi_os_acquire_object() is fixed in -rc4. I queued the
acpi_pci_link_set() improvement for sending on to Len, thanks.
On Mon, 7 Aug 2006, Andrew Morton wrote:
> acpi_os_acquire_object() is fixed in -rc4. I queued the
> acpi_pci_link_set() improvement for sending on to Len, thanks.
Thanks. Unfortunately, looking at the refactorized ACPI code in
2.6.18-rc4, there are still issues with sleeping functions called with
disabled interrupts (during resume), in ACPI code.
Two random examples:
- when acpi_pci_link_set() is called during resume (local irqs off), the
following callchain happens, which is bad: acpi_pci_link_resume ->
acpi_pci_link_set -> acpi_set_current_resources ->
acpi_rs_set_srs_method_data -> acpi_ns_evaluate -> acpi_ns_get_node ..
here the mutex is acquired. Not good.
- device_power_up -> sysdev_resume -> __sysdev_resume -> cpufreq_resume ->
blocking_notifier_call_chain -> down on semaphore. Not good.
Is there any general idea for solution?
--
JiKos.