[+cc Matthew] [+cc e1000-de...@lists.sourceforge.net for suspected 82575/82598 regression]
On Thu, Mar 28, 2013 at 01:24:55PM -0700, Yinghai Lu wrote: > patch for Roman > > On Thu, Mar 28, 2013 at 1:24 PM, Yinghai Lu <ying...@kernel.org> wrote: > > resending with adding To Roman. > > > > On Thu, Mar 28, 2013 at 5:46 AM, Bjorn Helgaas <bhelg...@google.com> wrote: > >> This patch might be *safe*, but it (and the changelog) are completely > >> unintelligible. > >> > >> The problem with applying an unintelligible stop-gap patch is that it > >> becomes forever part of the changelog, and it's a huge waste of time > >> to everybody who tries to understand the history later. That's why I > >> think it's worth spending some time to make a good patch now. > > > > Please check if attached patch is doing what you want. Patch inlined below for convenience. > Subject: [PATCH] PCI: Remove not needed check in disable aspm link > > Roman reported ath5k does not work anymore on 3.8. > Bisected to > | commit 8c33f51df406e1a1f7fa4e9b244845b7ebd61fa6 > | Author: Taku Izumi <izumi.t...@jp.fujitsu.com> > | Date: Tue Oct 30 15:27:13 2012 +0900 > | > | PCI/ACPI: Request _OSC control before scanning PCI root bus > | > | This patch moves up the code block to request _OSC control in order to > | separate ACPI work and PCI work in acpi_pci_root_add(). > > It make pci_disable_link_state does not work anymore as acpi_disabled > is set before pci root bus scanning. > It will skip that in quirks and pcie_aspm_sanity_check. I think this regression has nothing to do with pci_disable_link_state(). When aspm_disabled is set, pci_disable_link_state() doesn't do anything. In both 3.7 and 3.8, aspm_disabled is set in acpi_pci_root_add() before any driver probe routines are run, so it looks like calling pci_disable_link_state() from a driver had no effect even in 3.7. This is a problem, of course, but not the one Roman is seeing, because ath5k calls pci_disable_link_state() from the driver probe routine. There are also PCI_FIXUP_FINAL quirks for 82575 and 82598 NICs that call pci_disable_link_state(). In 3.7, these quirks are run before aspm_disabled is set, but 8c33f51d moved the pcie_no_aspm() call up before we start scanning the bus, so in 3.8, aspm_disabled is set *before* we run them. I think that means 8c33f51d broke all these quirks. That's also a problem, of course, but this isn't the one Roman is seeing either. I think the problem Roman is seeing happens when pcie_aspm_init_link_state() calls pcie_aspm_sanity_check() during device enumeration. In 3.8, the fact that aspm_disabled is already set by the time we get here means we skip the check for pre-1.1 PCIe devices, and I think *this* is what Roman is seeing. I suspect the following hunk of your patch is enough to fix things for Roman: > --- linux-2.6.orig/drivers/pci/pcie/aspm.c > +++ linux-2.6/drivers/pci/pcie/aspm.c > @@ -493,15 +492,6 @@ static int pcie_aspm_sanity_check(struct > return -EINVAL; > > /* > - * If ASPM is disabled then we're not going to change > - * the BIOS state. It's safe to continue even if it's a > - * pre-1.1 device > - */ > - > - if (aspm_disabled) > - continue; > - > - /* > * Disable ASPM for pre-1.1 PCIe device, we follow MS to use > * RBER bit to determine if a function is 1.1 version device > */ However, this test was added by Matthew in c9651e70, and I can't remove it unless we have an explanation of why removing it will not reintroduce the bug he was fixing. This code is such a terrible mess that it's not surprising at all that we have all these issues. But there's too much to untangle in v3.9; all we can hope for is to fix the regressions in v3.9 and clean it up later. > We could revert to old logic, but that will make booting path and hotplug > path with different aspm_disabled again. > > Acctually we don't need to check aspm_disabled in disable link, as > we already have protection about link state following. > > https://bugzilla.kernel.org/show_bug.cgi?id=55211 > http://article.gmane.org/gmane.linux.kernel.pci/20640 > > Need it for 3.8 stable. > > -v2: more cleanup > 1. remove aspm_support_enabled, as if it compiled in, support is there > so even user pass aspm=off, link_state still get allocated, > then we will have chance to disable aspm on devices from > buggy setting of BIOS. > 2. move pcie_no_aspm() calling for fadt disabling before scanning > requested by Bjorn. > > Reported-by: Roman Yepishev <roman.yepis...@gmail.com> > Bisected-by: Roman Yepishev <roman.yepis...@gmail.com> > Signed-off-by: Yinghai Lu <ying...@kernel.org> > Cc: Taku Izumi <izumi.t...@jp.fujitsu.com> > Cc: Kenji Kaneshige <kaneshige.ke...@jp.fujitsu.com> > > --- > drivers/acpi/pci_root.c | 25 +++++++++--------------- > drivers/pci/pcie/aspm.c | 48 > ++--------------------------------------------- > include/linux/pci-aspm.h | 4 --- > include/linux/pci.h | 2 - > 4 files changed, 14 insertions(+), 65 deletions(-) > > Index: linux-2.6/drivers/acpi/pci_root.c > =================================================================== > --- linux-2.6.orig/drivers/acpi/pci_root.c > +++ linux-2.6/drivers/acpi/pci_root.c > @@ -415,7 +415,6 @@ static int acpi_pci_root_add(struct acpi > struct acpi_pci_root *root; > struct acpi_pci_driver *driver; > u32 flags, base_flags; > - bool is_osc_granted = false; > > root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL); > if (!root) > @@ -494,6 +493,11 @@ static int acpi_pci_root_add(struct acpi > flags = base_flags; > } > } > + > + /* ASPM setting */ > + if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) > + pcie_no_aspm(); > + > if (!pcie_ports_disabled > && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) { > flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL > @@ -513,16 +517,17 @@ static int acpi_pci_root_add(struct acpi > > status = acpi_pci_osc_control_set(device->handle, &flags, > OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL); > - if (ACPI_SUCCESS(status)) { > - is_osc_granted = true; > + if (ACPI_SUCCESS(status)) > dev_info(&device->dev, > "ACPI _OSC control (0x%02x) granted\n", flags); > - } else { > - is_osc_granted = false; > + else { > dev_info(&device->dev, > "ACPI _OSC request failed (%s), " > "returned control mask: 0x%02x\n", > acpi_format_exception(status), flags); > + pr_info("ACPI _OSC control for PCIe not granted, " > + "disabling ASPM\n"); > + pcie_no_aspm(); > } > } else { > dev_info(&device->dev, > @@ -554,16 +559,6 @@ static int acpi_pci_root_add(struct acpi > goto out_del_root; > } > > - /* ASPM setting */ > - if (is_osc_granted) { > - if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) > - pcie_clear_aspm(root->bus); > - } else { > - pr_info("ACPI _OSC control for PCIe not granted, " > - "disabling ASPM\n"); > - pcie_no_aspm(); > - } > - > pci_acpi_add_bus_pm_notifier(device, root->bus); > if (device->wakeup.flags.run_wake) > device_set_run_wake(root->bus->bridge, true); > Index: linux-2.6/drivers/pci/pcie/aspm.c > =================================================================== > --- linux-2.6.orig/drivers/pci/pcie/aspm.c > +++ linux-2.6/drivers/pci/pcie/aspm.c > @@ -69,7 +69,6 @@ struct pcie_link_state { > }; > > static int aspm_disabled, aspm_force; > -static bool aspm_support_enabled = true; > static DEFINE_MUTEX(aspm_lock); > static LIST_HEAD(link_list); > > @@ -493,15 +492,6 @@ static int pcie_aspm_sanity_check(struct > return -EINVAL; > > /* > - * If ASPM is disabled then we're not going to change > - * the BIOS state. It's safe to continue even if it's a > - * pre-1.1 device > - */ > - > - if (aspm_disabled) > - continue; > - > - /* > * Disable ASPM for pre-1.1 PCIe device, we follow MS to use > * RBER bit to determine if a function is 1.1 version device > */ > @@ -556,9 +546,6 @@ void pcie_aspm_init_link_state(struct pc > struct pcie_link_state *link; > int blacklist = !!pcie_aspm_sanity_check(pdev); > > - if (!aspm_support_enabled) > - return; > - > if (!pci_is_pcie(pdev) || pdev->link_state) > return; > if (pci_pcie_type(pdev) != PCI_EXP_TYPE_ROOT_PORT && > @@ -718,15 +705,11 @@ void pcie_aspm_powersave_config_link(str > * pci_disable_link_state - disable pci device's link state, so the link will > * never enter specific states > */ > -static void __pci_disable_link_state(struct pci_dev *pdev, int state, bool > sem, > - bool force) > +static void __pci_disable_link_state(struct pci_dev *pdev, int state, bool > sem) > { > struct pci_dev *parent = pdev->bus->self; > struct pcie_link_state *link; > > - if (aspm_disabled && !force) > - return; > - > if (!pci_is_pcie(pdev)) > return; > > @@ -757,34 +740,16 @@ static void __pci_disable_link_state(str > > void pci_disable_link_state_locked(struct pci_dev *pdev, int state) > { > - __pci_disable_link_state(pdev, state, false, false); > + __pci_disable_link_state(pdev, state, false); > } > EXPORT_SYMBOL(pci_disable_link_state_locked); > > void pci_disable_link_state(struct pci_dev *pdev, int state) > { > - __pci_disable_link_state(pdev, state, true, false); > + __pci_disable_link_state(pdev, state, true); > } > EXPORT_SYMBOL(pci_disable_link_state); > > -void pcie_clear_aspm(struct pci_bus *bus) > -{ > - struct pci_dev *child; > - > - if (aspm_force) > - return; > - > - /* > - * Clear any ASPM setup that the firmware has carried out on this bus > - */ > - list_for_each_entry(child, &bus->devices, bus_list) { > - __pci_disable_link_state(child, PCIE_LINK_STATE_L0S | > - PCIE_LINK_STATE_L1 | > - PCIE_LINK_STATE_CLKPM, > - false, true); > - } > -} > - > static int pcie_aspm_set_policy(const char *val, struct kernel_param *kp) > { > int i; > @@ -944,7 +909,6 @@ static int __init pcie_aspm_disable(char > if (!strcmp(str, "off")) { > aspm_policy = POLICY_DEFAULT; > aspm_disabled = 1; > - aspm_support_enabled = false; > printk(KERN_INFO "PCIe ASPM is disabled\n"); > } else if (!strcmp(str, "force")) { > aspm_force = 1; > @@ -980,9 +944,3 @@ int pcie_aspm_enabled(void) > return !aspm_disabled; > } > EXPORT_SYMBOL(pcie_aspm_enabled); > - > -bool pcie_aspm_support_enabled(void) > -{ > - return aspm_support_enabled; > -} > -EXPORT_SYMBOL(pcie_aspm_support_enabled); > Index: linux-2.6/include/linux/pci-aspm.h > =================================================================== > --- linux-2.6.orig/include/linux/pci-aspm.h > +++ linux-2.6/include/linux/pci-aspm.h > @@ -29,7 +29,6 @@ extern void pcie_aspm_pm_state_change(st > extern void pcie_aspm_powersave_config_link(struct pci_dev *pdev); > extern void pci_disable_link_state(struct pci_dev *pdev, int state); > extern void pci_disable_link_state_locked(struct pci_dev *pdev, int state); > -extern void pcie_clear_aspm(struct pci_bus *bus); > extern void pcie_no_aspm(void); > #else > static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) > @@ -47,9 +46,6 @@ static inline void pcie_aspm_powersave_c > static inline void pci_disable_link_state(struct pci_dev *pdev, int state) > { > } > -static inline void pcie_clear_aspm(struct pci_bus *bus) > -{ > -} > static inline void pcie_no_aspm(void) > { > } > Index: linux-2.6/include/linux/pci.h > =================================================================== > --- linux-2.6.orig/include/linux/pci.h > +++ linux-2.6/include/linux/pci.h > @@ -1168,7 +1168,7 @@ static inline int pcie_aspm_enabled(void > static inline bool pcie_aspm_support_enabled(void) { return false; } > #else > extern int pcie_aspm_enabled(void); > -extern bool pcie_aspm_support_enabled(void); > +static inline bool pcie_aspm_support_enabled(void) { return true; } > #endif > > #ifdef CONFIG_PCIEAER -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
