Re: 2.6.12-rc1-mm1: Kernel BUG at pci:389

Andrew Morton
2005-03-22T01:16:44Z

Pavel Machek <pavel@suse.cz> wrote:
>
> Hi!
>
> > > On Monday, 21 of March 2005 11:51, you wrote:
> > > >
> > > > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.12-rc1/2.6.12-rc1-mm1/
> > >
> > > I get the following BUG every time I try to suspend my box to disk.
> >
> > Pavel, that's the BUG() in pci_choose_state(). I did have some
> > reject-fixing to do on that wrt a change in Greg's tree, so maybe there was
> > some incompatible intent in there.
> >
> > I dunno why pci_choose_state() is saying that it received PCI_D1, when
> > prepare_devices() is passing down PMSG_FREEZE?
>
> Uf, I don't know what version that was.. I think I have
>
> VERSION = 2
> PATCHLEVEL = 6
> SUBLEVEL = 12
> EXTRAVERSION =-rc1-mm1

yes, the report was against 2.6.12-rc1-mm1.

> and that says:
>
> #define PMSG_FREEZE ((__force pm_message_t) 3)
>
> ... I certainly have _FREEZE defined as 1 in my local tree, but I do
> not see that change in -mm yet.

Both 2.6.12-rc1-mm1 and 2.6.12-rc1 have:

#define PMSG_FREEZE ((__force pm_message_t) 3)
#define PMSG_SUSPEND ((__force pm_message_t) 3)
#define PMSG_ON ((__force pm_message_t) 0)

which looks odd.

> Possibly pm.h changes went in faster than pci.c or something like
> that?

grep says that 2.6.12-rc1-mm1 has these patches from you:

fix-suspend-resume-on-via-velocity.patch
x86-fix-esp-corruption-cpu-bug-take-2.patch
swsusp-add-missing-refrigerator-calls.patch
suspend-to-ram-update-videotxt-with-more-systems.patch
pm-remove-obsolete-pm_-from-vtc.patch
swsusp-small-updates.patch
swsusp-1-1-kill-swsusp_restore.patch
pcmcia-id_table-for-orinoco_cs.patch
fix-pm_message_t-in-generic-code.patch
fix-u32-vs-pm_message_t-in-usb.patch
more-pm_message_t-fixes.patch
fix-u32-vs-pm_message_t-confusion-in-oss.patch
fix-u32-vs-pm_message_t-confusion-in-pcmcia.patch
fix-u32-vs-pm_message_t-confusion-in-framebuffers.patch
fix-u32-vs-pm_message_t-confusion-in-mmc.patch
fix-u32-vs-pm_message_t-confusion-in-serials.patch
fix-u32-vs-pm_message_t-in-macintosh.patch
fix-u32-vs-pm_message_t-confusion-in-agp.patch

> I reproduced it here.. I do not know who introduced
> platform_pci_choose_state, but it is *very* wrong. It returns
> it. Should it return pci_power_t? It probably should to match
> pci_choose_state, but that int is retyped to pm_message_t. Oops.

That change came from Len. I've appended the two relevant patches below.

So hm. We have incompatible changes in flight. That doesn't happen very
often.

Could I suggest that you prepare a fixup against 2.6.12-rc1-mm1 and send
that to Len and myself? If that fixup is not suitable for a 2.6.12-rc1
based tree then I can look after it until things get flushed out.

(Len, platform_pci_set_power_state shouldn't be initialised to NULL).

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
# 2005/03/19 00:15:48-05:00 len.brown@intel.com
# [ACPI] PCI can now get suspend state from firmware
#
# pci_choose_state() can now call
# platform_pci_choose_state()
# and ACPI can answer
#
# http://bugzilla.kernel.org/show_bug.cgi?id=4277
#
# Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
# Signed-off-by: Len Brown <len.brown@intel.com>
#
# drivers/pci/pci.h
# 2005/03/19 00:15:24-05:00 len.brown@intel.com +3 -0
# add platform_pci_choose_state()
#
# drivers/pci/pci.c
# 2005/03/19 00:15:24-05:00 len.brown@intel.com +7 -0
# add platform_pci_choose_state()
#
# drivers/pci/pci-acpi.c
# 2005/03/19 00:15:24-05:00 len.brown@intel.com +46 -1
# add platform_pci_choose_state()
#
diff -Nru a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
--- a/drivers/pci/pci-acpi.c 2005-03-21 17:01:44 -08:00
+++ b/drivers/pci/pci-acpi.c 2005-03-21 17:01:44 -08:00
@@ -1,6 +1,6 @@
/*
* File: pci-acpi.c
- * Purpose: Provide PCI support in ACPI
+ * Purpose: Provde PCI support in ACPI
*
* Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
* Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
@@ -17,6 +17,7 @@
#include <acpi/acpi_bus.h>

#include <linux/pci-acpi.h>
+#include "pci.h"

static u32 ctrlset_buf[3] = {0, 0, 0};
static u32 global_ctrlsets = 0;
@@ -209,6 +210,49 @@
}
EXPORT_SYMBOL(pci_osc_control_set);

+/*
+ * _SxD returns the D-state with the highest power
+ * (lowest D-state number) supported in the S-state "x".
+ *
+ * If the devices does not have a _PRW
+ * (Power Resources for Wake) supporting system wakeup from "x"
+ * then the OS is free to choose a lower power (higher number
+ * D-state) than the return value from _SxD.
+ *
+ * But if _PRW is enabled at S-state "x", the OS
+ * must not choose a power lower than _SxD --
+ * unless the device has an _SxW method specifying
+ * the lowest power (highest D-state number) the device
+ * may enter while still able to wake the system.
+ *
+ * ie. depending on global OS policy:
+ *
+ * if (_PRW at S-state x)
+ * choose from highest power _SxD to lowest power _SxW
+ * else // no _PRW at S-state x
+ * choose highest power _SxD or any lower power
+ *
+ * currently we simply return _SxD, if present.
+ */
+
+static int acpi_pci_choose_state(struct pci_dev *pdev, pm_message_t state)
+{
+ char dstate_str[] = "_S0D";
+ acpi_status status;
+ unsigned long val;
+ struct device *dev = &pdev->dev;
+
+ /* Fixme: the check is wrong after pm_message_t is a struct */
+ if ((state >= PM_SUSPEND_MAX) || !DEVICE_ACPI_HANDLE(dev))
+ return -EINVAL;
+ dstate_str[2] += state; /* _S1D, _S2D, _S3D, _S4D */
+ status = acpi_evaluate_integer(DEVICE_ACPI_HANDLE(dev), dstate_str,
+ NULL, &val);
+ if (ACPI_SUCCESS(status))
+ return val;
+ return -ENODEV;
+}
+
/* ACPI bus type */
static int pci_acpi_find_device(struct device *dev, acpi_handle *handle)
{
@@ -255,6 +299,7 @@
ret = register_acpi_bus_type(&pci_acpi_bus);
if (ret)
return 0;
+ platform_pci_choose_state = acpi_pci_choose_state;
return 0;
}
arch_initcall(pci_acpi_init);
diff -Nru a/drivers/pci/pci.c b/drivers/pci/pci.c
--- a/drivers/pci/pci.c 2005-03-21 17:01:44 -08:00
+++ b/drivers/pci/pci.c 2005-03-21 17:01:44 -08:00
@@ -317,12 +317,19 @@
* Returns PCI power state suitable for given device and given system
* message.
*/
+int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state) = NULL;

pci_power_t pci_choose_state(struct pci_dev *dev, u32 state)
{
+ int ret;
if (!pci_find_capability(dev, PCI_CAP_ID_PM))
return PCI_D0;

+ if (platform_pci_choose_state) {
+ ret = platform_pci_choose_state(dev, state);
+ if (ret >= 0)
+ state = ret;
+ }
switch (state) {
case 0: return PCI_D0;
case 2: return PCI_D2;
diff -Nru a/drivers/pci/pci.h b/drivers/pci/pci.h
--- a/drivers/pci/pci.h 2005-03-21 17:01:44 -08:00
+++ b/drivers/pci/pci.h 2005-03-21 17:01:44 -08:00
@@ -11,6 +11,9 @@
void (*alignf)(void *, struct resource *,
unsigned long, unsigned long),
void *alignf_data);
+/* Firmware callbacks */
+extern int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
+
/* PCI /proc functions */
#ifdef CONFIG_PROC_FS
extern int pci_proc_attach_device(struct pci_dev *dev);

# This is a BitKeeper generated diff -Nru style patch.
#
# ChangeSet
# 2005/03/19 00:16:18-05:00 len.brown@intel.com
# [ACPI] pci_set_power_state() now calls
# platform_pci_set_power_state()
# and ACPI can answer
#
# http://bugzilla.kernel.org/show_bug.cgi?id=4277
#
# Signed-off-by: David Shaohua Li <shaohua.li@intel.com>
# Signed-off-by: Len Brown <len.brown@intel.com>
#
# drivers/pci/pci.h
# 2005/03/03 04:20:56-05:00 len.brown@intel.com +1 -0
# pci_set_power_state() now calls platform_pci_set_power_state()
#
# drivers/pci/pci.c
# 2005/03/03 04:20:56-05:00 len.brown@intel.com +9 -2
# pci_set_power_state() now calls platform_pci_set_power_state()
#
# drivers/pci/pci-acpi.c
# 2005/03/03 04:28:23-05:00 len.brown@intel.com +19 -0
# pci_set_power_state() now calls platform_pci_set_power_state()
#
# drivers/acpi/bus.c
# 2005/03/03 04:20:56-05:00 len.brown@intel.com +7 -1
# pci_set_power_state() now calls platform_pci_set_power_state()
#
diff -Nru a/drivers/acpi/bus.c b/drivers/acpi/bus.c
--- a/drivers/acpi/bus.c 2005-03-21 17:02:38 -08:00
+++ b/drivers/acpi/bus.c 2005-03-21 17:02:38 -08:00
@@ -212,6 +212,12 @@
ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Device is not power manageable\n"));
return_VALUE(-ENODEV);
}
+ /*
+ * Get device's current power state if it's unknown
+ * This means device power state isn't initialized or previous setting failed
+ */
+ if (device->power.state == ACPI_STATE_UNKNOWN)
+ acpi_bus_get_power(device->handle, &device->power.state);
if (state == device->power.state) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n", state));
return_VALUE(0);
@@ -231,7 +237,7 @@
* On transitions to a high-powered state we first apply power (via
* power resources) then evalute _PSx. Conversly for transitions to
* a lower-powered state.
- */
+ */
if (state < device->power.state) {
if (device->power.flags.power_resources) {
result = acpi_power_transition(device, state);
diff -Nru a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
--- a/drivers/pci/pci-acpi.c 2005-03-21 17:02:38 -08:00
+++ b/drivers/pci/pci-acpi.c 2005-03-21 17:02:38 -08:00
@@ -253,6 +253,24 @@
return -ENODEV;
}

+static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
+{
+ acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
+ static int state_conv[] = {
+ [0] = 0,
+ [1] = 1,
+ [2] = 2,
+ [3] = 3,
+ [4] = 3
+ };
+ int acpi_state = state_conv[(int __force) state];
+
+ if (!handle)
+ return -ENODEV;
+ return acpi_bus_set_power(handle, acpi_state);
+}
+
+
/* ACPI bus type */
static int pci_acpi_find_device(struct device *dev, acpi_handle *handle)
{
@@ -300,6 +318,7 @@
if (ret)
return 0;
platform_pci_choose_state = acpi_pci_choose_state;
+ platform_pci_set_power_state = acpi_pci_set_power_state;
return 0;
}
arch_initcall(pci_acpi_init);
diff -Nru a/drivers/pci/pci.c b/drivers/pci/pci.c
--- a/drivers/pci/pci.c 2005-03-21 17:02:38 -08:00
+++ b/drivers/pci/pci.c 2005-03-21 17:02:38 -08:00
@@ -240,7 +240,7 @@
* -EIO if device does not support PCI PM.
* 0 if we can successfully change the power state.
*/
-
+int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t) = NULL;
int
pci_set_power_state(struct pci_dev *dev, pci_power_t state)
{
@@ -304,8 +304,15 @@
msleep(10);
else if (state == PCI_D2 || dev->current_state == PCI_D2)
udelay(200);
- dev->current_state = state;

+ /*
+ * Give firmware a chance to be called, such as ACPI _PRx, _PSx
+ * Firmware method after natice method ?
+ */
+ if (platform_pci_set_power_state)
+ platform_pci_set_power_state(dev, state);
+
+ dev->current_state = state;
return 0;
}

diff -Nru a/drivers/pci/pci.h b/drivers/pci/pci.h
--- a/drivers/pci/pci.h 2005-03-21 17:02:38 -08:00
+++ b/drivers/pci/pci.h 2005-03-21 17:02:38 -08:00
@@ -13,6 +13,7 @@
void *alignf_data);
/* Firmware callbacks */
extern int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
+extern int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t state);

/* PCI /proc functions */
#ifdef CONFIG_PROC_FS