commit 08d0cc5f34265d1a1e3031f319f594bd1970976c upstream.
This change is desired because without it, it has been observed that re-applying aspm settings can cause the system to crash with certain pci devices (ie. Genesys GL9755).
Tested by issuing 100 suspend/resume cycles on a symptomatic system running 5.15.107.
L1 settings looked identical before and after: ``` localhost ~ # lspci -vvv -d 0x17a0: | grep L1Sub L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ ASPM_L1.1+ L1_PM_Substates+ L1SubCtl1: PCI-PM_L1.2- PCI-PM_L1.1+ ASPM_L1.2- ASPM_L1.1+ L1SubCtl2: T_PwrOn=3100us ```
Cc: stable@vger.kernel.org # 5.15.y
On Fri, Apr 21, 2023 at 12:42:30PM -0600, Mark Hasemeyer wrote:
commit 08d0cc5f34265d1a1e3031f319f594bd1970976c upstream.
This change is desired because without it, it has been observed that re-applying aspm settings can cause the system to crash with certain pci devices (ie. Genesys GL9755).
Tested by issuing 100 suspend/resume cycles on a symptomatic system running 5.15.107.
L1 settings looked identical before and after:
localhost ~ # lspci -vvv -d 0x17a0: | grep L1Sub L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ ASPM_L1.1+ L1_PM_Substates+ L1SubCtl1: PCI-PM_L1.2- PCI-PM_L1.1+ ASPM_L1.2- ASPM_L1.1+ L1SubCtl2: T_PwrOn=3100usCc: stable@vger.kernel.org # 5.15.y
Odd, it does not apply cleanly, so how was this tested? Can you please send the tested backport that you have so we know to get it correct?
thanks,
greg k-h
Odd, it does not apply cleanly, so how was this tested? Can you please send the tested backport that you have so we know to get it correct?
Sorry about that. I had to apply a trivial backport as `pci_set_low_power_state` does not exist in v5.15. It was tested by using an RTC wake in combination with using the sysfs to trigger a suspend: ``` echo +5 > /sys/class/rtc/rtc0/wakealarm && echo freeze > /sys/power/state ```
Patch below. ------------------------------------ From 5ca368f6918710bf491feee54e09a060de835d3f Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng kai.heng.feng@canonical.com Date: Mon, 11 Jul 2022 18:07:01 -0500 Subject: [PATCH] PCI/ASPM: Remove pcie_aspm_pm_state_change()
pcie_aspm_pm_state_change() was introduced at the inception of PCIe ASPM code, but it can cause some issues. For instance, when ASPM config is changed via sysfs, those changes won't persist across power state change because pcie_aspm_pm_state_change() overwrites them.
Also, if the driver restores L1SS [1] after system resume, the restored state will also be overwritten by pcie_aspm_pm_state_change().
Remove pcie_aspm_pm_state_change(). If there's any hardware that really needs it to function, a quirk can be used instead.
[1] https://lore.kernel.org/linux-pci/20220201123536.12962-1-vidyas@nvidia.com/ Link: https://lore.kernel.org/r/20220509073639.2048236-1-kai.heng.feng@canonical.c... [bhelgaas: remove additional pcie_aspm_pm_state_change() call in pci_set_low_power_state(), added by 10aa5377fc8a ("PCI/PM: Split pci_raw_set_power_state()") and moved by 7957d201456f ("PCI/PM: Relocate pci_set_low_power_state()")] Signed-off-by: Kai-Heng Feng kai.heng.feng@canonical.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Mark Hasemeyer markhas@chromium.org --- drivers/pci/pci.c | 3 --- drivers/pci/pci.h | 2 -- drivers/pci/pcie/aspm.c | 19 ------------------- 3 files changed, 24 deletions(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 649df298869c..4aa2e655398c 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1140,9 +1140,6 @@ static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state) if (need_restore) pci_restore_bars(dev);
- if (dev->bus->self) - pcie_aspm_pm_state_change(dev->bus->self); - return 0; }
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 72280e9b23b2..e6ea6e950428 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -595,12 +595,10 @@ bool pcie_wait_for_link(struct pci_dev *pdev, bool active); #ifdef CONFIG_PCIEASPM void pcie_aspm_init_link_state(struct pci_dev *pdev); void pcie_aspm_exit_link_state(struct pci_dev *pdev); -void pcie_aspm_pm_state_change(struct pci_dev *pdev); void pcie_aspm_powersave_config_link(struct pci_dev *pdev); #else static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { } static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { } -static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev) { } static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { } #endif
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 013a47f587ce..b3ad316418f1 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1020,25 +1020,6 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev) up_read(&pci_bus_sem); }
-/* @pdev: the root port or switch downstream port */ -void pcie_aspm_pm_state_change(struct pci_dev *pdev) -{ - struct pcie_link_state *link = pdev->link_state; - - if (aspm_disabled || !link) - return; - /* - * Devices changed PM state, we should recheck if latency - * meets all functions' requirement - */ - down_read(&pci_bus_sem); - mutex_lock(&aspm_lock); - pcie_update_aspm_capable(link->root); - pcie_config_aspm_path(link); - mutex_unlock(&aspm_lock); - up_read(&pci_bus_sem); -} - void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { struct pcie_link_state *link = pdev->link_state;
On Mon, Apr 24, 2023 at 12:35:36PM -0600, Mark Hasemeyer wrote:
Odd, it does not apply cleanly, so how was this tested? Can you please send the tested backport that you have so we know to get it correct?
Sorry about that. I had to apply a trivial backport as `pci_set_low_power_state` does not exist in v5.15. It was tested by using an RTC wake in combination with using the sysfs to trigger a suspend:
echo +5 > /sys/class/rtc/rtc0/wakealarm && echo freeze > /sys/power/statePatch below.
From 5ca368f6918710bf491feee54e09a060de835d3f Mon Sep 17 00:00:00 2001
From: Kai-Heng Feng kai.heng.feng@canonical.com Date: Mon, 11 Jul 2022 18:07:01 -0500 Subject: [PATCH] PCI/ASPM: Remove pcie_aspm_pm_state_change()
pcie_aspm_pm_state_change() was introduced at the inception of PCIe ASPM code, but it can cause some issues. For instance, when ASPM config is changed via sysfs, those changes won't persist across power state change because pcie_aspm_pm_state_change() overwrites them.
Also, if the driver restores L1SS [1] after system resume, the restored state will also be overwritten by pcie_aspm_pm_state_change().
Remove pcie_aspm_pm_state_change(). If there's any hardware that really needs it to function, a quirk can be used instead.
[1] https://lore.kernel.org/linux-pci/20220201123536.12962-1-vidyas@nvidia.com/ Link: https://lore.kernel.org/r/20220509073639.2048236-1-kai.heng.feng@canonical.c... [bhelgaas: remove additional pcie_aspm_pm_state_change() call in pci_set_low_power_state(), added by 10aa5377fc8a ("PCI/PM: Split pci_raw_set_power_state()") and moved by 7957d201456f ("PCI/PM: Relocate pci_set_low_power_state()")] Signed-off-by: Kai-Heng Feng kai.heng.feng@canonical.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Mark Hasemeyer markhas@chromium.org
drivers/pci/pci.c | 3 --- drivers/pci/pci.h | 2 -- drivers/pci/pcie/aspm.c | 19 ------------------- 3 files changed, 24 deletions(-)
What is the git commit id of this change in Linus's tree?
And can you send it as a stand-alone patch, not one that I have to hand-edit out of an email to use? Doing that does not scale at the rate of change we currently deal with at all.
thanks,
greg k-h
What is the git commit id of this change in Linus's tree?
08d0cc5f34265d1a1e3031f319f594bd1970976c
And can you send it as a stand-alone patch, not one that I have to hand-edit out of an email to use? Doing that does not scale at the rate of change we currently deal with at all.
Understood. I'll send a stand-alone patch.
linux-stable-mirror@lists.linaro.org
-
Greg KH -
Mark Hasemeyer