| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <CAErSpo57jEuoKLnqVp6V-fkb8TBj+cUv3kgEbfpvFErE315pCA@mail.gmail.com>
Date: Mon, 30 Apr 2012 15:38:55 -0600
From: Bjorn Helgaas <bhelgaas@...gle.com>
To: "Rafael J. Wysocki" <rjw@...k.pl>
Cc: Len Brown <lenb@...nel.org>,
ACPI Devel Mailing List <linux-acpi@...r.kernel.org>,
Linux PM list <linux-pm@...r.kernel.org>,
linux-pci@...r.kernel.org, Alan Stern <stern@...land.harvard.edu>,
"Oleksij Rempel (fishor)" <bug-track@...her-privat.net>,
LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] ACPI / PCI: Make _SxD/_SxW check follow ACPI 4.0a spec
On Mon, Apr 30, 2012 at 3:41 PM, Rafael J. Wysocki <rjw@...k.pl> wrote:
> On Monday, April 30, 2012, Bjorn Helgaas wrote:
>> On Sun, Apr 29, 2012 at 2:44 PM, Rafael J. Wysocki <rjw@...k.pl> wrote:
>> > From: Oleksij Rempel <bug-track@...her-privat.net>
>> >
>> > This patch makes _SxD/_SxW check follow the ACPI 4.0a specification
>> > more closely and fixes suspend bug found on ASUS Zenbook UX31E.
>> >
>> > Some OEM use _SxD fileds do blacklist brocken Dx states.
>> > If _SxD/_SxW return values are check before suspend as appropriate,
>> > some nasty suspend/resume issues may be avoided.
>> >
>> > References: https://bugzilla.kernel.org/show_bug.cgi?id=42728
>> > Signed-off-by: Oleksij Rempel <bug-track@...her-privat.net>
>> > Signed-off-by: Rafael J. Wysocki <rjw@...k.pl>
>> > ---
>> >
>> > Bjorn, Len,
>> >
>> > This is -stable material and therefore v3.4 as well, IMO. Please let me
>> > know if one of you can take it or whether you want me to handle it all the
>> > way to Linus.
>>
>> I'm OK with this from a PCI perspective. Most of the change is in
>> ACPI, so I propose that either you or Len take care of it.
>>
>> The second paragraph of the changelog has several typos
>> (fileds/fields, do/to, brocken/broken, etc).
>
> Thanks for spotting that, the version below should be better.
>
> I'll wait for Len to respond till Friday and will take care of the patch myself
> if he doesn't say anything.
>
> May I assume an ACK from you?
Yep, sorry :)
Acked-by: Bjorn Helgaas <bhelgaas@...gle.com>
> ---
> From: Oleksij Rempel <bug-track@...her-privat.net>
> Subject: ACPI / PCI: Make _SxD/_SxW check follow ACPI 4.0a spec
>
> This patch makes _SxD/_SxW check follow the ACPI 4.0a specification
> more closely and fixes suspend bug found on ASUS Zenbook UX31E.
>
> Some OEM use _SxD fields to blacklist broken device Dx states, so
> if _SxD/_SxW return values are checked before suspend as appropriate,
> some nasty suspend/resume issues may be avoided.
>
> References: https://bugzilla.kernel.org/show_bug.cgi?id=42728
> Signed-off-by: Oleksij Rempel <bug-track@...her-privat.net>
> Signed-off-by: Rafael J. Wysocki <rjw@...k.pl>
> ---
> drivers/acpi/sleep.c | 22 +++++++++++++++++++++-
> drivers/pci/pci.c | 12 +++++++++++-
> 2 files changed, 32 insertions(+), 2 deletions(-)
>
> Index: linux/drivers/acpi/sleep.c
> ===================================================================
> --- linux.orig/drivers/acpi/sleep.c
> +++ linux/drivers/acpi/sleep.c
> @@ -720,10 +720,30 @@ int acpi_pm_device_sleep_state(struct de
> *
> * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
> * provided -- that's our fault recovery, we ignore retval.
> + *
> + * According to ACPI 4.0a (April 5, 2010), page 294,
> + * Table 7-7 S3 Action / Result Table, we need to evaluate _SxW in
> + * addition to _SxD if the device is configured for wakeup:
> + * Desired Action | _S3D | _PRW | _S3W | Resultant D-state
> + * Enter S3 | N/A | D/C | N/A | OSPM decides
> + * Enter S3, No Wake | 2 | D/C | D/C | Enter D2 or D3
> + * Enter S3, Wake | 2 | 3 | N/A | Enter D2
> + * Enter S3, Wake | 2 | 3 | 3 | Enter D2 or D3
> + * Enter S3, Wake | N/A | 3 | 2 | Enter D0, D1 or D2
> */
> - if (acpi_target_sleep_state > ACPI_STATE_S0)
> + if (acpi_target_sleep_state > ACPI_STATE_S0) {
> + acpi_status status;
> +
> acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
>
> + if (device_may_wakeup(dev)) {
> + acpi_method[3] = 'W';
> + status = acpi_evaluate_integer(handle, acpi_method,
> + NULL, &d_max);
> + if (ACPI_FAILURE(status))
> + d_max = d_min;
> + }
> + }
> /*
> * If _PRW says we can wake up the system from the target sleep state,
> * the D-state returned by _SxD is sufficient for that (we assume a
> Index: linux/drivers/pci/pci.c
> ===================================================================
> --- linux.orig/drivers/pci/pci.c
> +++ linux/drivers/pci/pci.c
> @@ -1691,10 +1691,20 @@ pci_power_t pci_target_state(struct pci_
> {
> pci_power_t target_state = PCI_D3hot;
>
> - if (platform_pci_power_manageable(dev)) {
> + /*
> + * According to ACPI 4.0a,7.2 Device Power Management Objects, device
> + * with wake capability should have _PRW or _PSW object and can have
> + * _SxD or _SxW object.
> + * It looks like some OEMs use this fields to avoid buggy Dx states
> + * of devices, so we need to check for _PRW or _PSW and see if _SxD or
> + * _SxW indicate to overwrite Dx.
> + */
> + if (platform_pci_power_manageable(dev)
> + || platform_pci_can_wakeup(dev)) {
> /*
> * Call the platform to choose the target state of the device
> * and enable wake-up from this state if supported.
> + * (Check _SxD and _SxW)
> */
> pci_power_t state = platform_pci_choose_state(dev);
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists