summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/eeh_pe.c
AgeCommit message (Collapse)Author
2014-08-05powerpc/eeh: Aux PE data for error logGavin Shan
The patch allows PE (struct eeh_pe) instance to have auxillary data, whose size is configurable on basis of platform. For PowerNV, the auxillary data will be used to cache PHB diag-data for that PE (frozen PE or fenced PHB). In turn, we can retrieve the diag-data at any later points. It's useful for the case of VFIO PCI devices where the error log should be cached, and then be retrieved by the guest at later point. Also, it can avoid PHB diag-data overwritting if another frozen PE reported and the previous diag-data isn't fetched by guest. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Replace pr_warning() with pr_warn()Gavin Shan
pr_warn() is equal to pr_warning(), but the former is a bit more formal according to commit fc62f2f ("kernel.h: add pr_warn for symmetry to dev_warn, netdev_warn"). The patch replaces pr_warning() with pr_warn(). Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: Wrong place to call pci_get_slot()Mike Qiu
pci_get_slot() is called with hold of PCI bus semaphore and it's not safe to be called in interrupt context. However, we possibly checks EEH error and calls the function in interrupt context. To avoid using pci_get_slot(), we turn into device tree for fetching location code. Otherwise, we might run into WARN_ON() as following messages indicate: WARNING: at drivers/pci/search.c:223 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.16.0-rc3+ #72 task: c000000001367af0 ti: c000000001444000 task.ti: c000000001444000 NIP: c000000000497b70 LR: c000000000037530 CTR: 000000003003d114 REGS: c000000001446fa0 TRAP: 0700 Not tainted (3.16.0-rc3+) MSR: 9000000000029032 <SF,HV,EE,ME,IR,DR,RI> CR: 48002422 XER: 20000000 CFAR: c00000000003752c SOFTE: 0 : NIP [c000000000497b70] .pci_get_slot+0x40/0x110 LR [c000000000037530] .eeh_pe_loc_get+0x150/0x190 Call Trace: .of_get_property+0x30/0x60 (unreliable) .eeh_pe_loc_get+0x150/0x190 .eeh_dev_check_failure+0x1b4/0x550 .eeh_check_failure+0x90/0xf0 .lpfc_sli_check_eratt+0x504/0x7c0 [lpfc] .lpfc_poll_eratt+0x64/0x100 [lpfc] .call_timer_fn+0x64/0x190 .run_timer_softirq+0x2cc/0x3e0 Cc: stable@vger.kernel.org Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com> Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05powerpc/eeh: sysfs entries lostMike Qiu
The sysfs entries are lost because of commit 2213fb1 ("powerpc/eeh: Skip eeh sysfs when eeh is disabled"). That commit added condition to create sysfs entries with EEH_ENABLED, which isn't populated when trying to create sysfs entries on PowerNV platform during system boot time. The patch fixes the issue by: * Reoder EEH initialization functions so that they're same on PowerNV/pSeries. * Cache PE's primary bus by PowerNV platform instead of EEH core to avoid kernel crash caused by the function reorder. Another benefit with this is to avoid one eeh_probe_mode_dev() in EEH core. Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com> Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11powerpc/eeh: Dump PE location codeGavin Shan
As Ben suggested, it's meaningful to dump PE's location code for site engineers when hitting EEH errors. The patch introduces function eeh_pe_loc_get() to retireve the location code from dev-tree so that we can output it when hitting EEH errors. If primary PE bus is root bus, the PHB's dev-node would be tried prior to root port's dev-node. Otherwise, the upstream bridge's dev-node of the primary PE bus will be check for the location code directly. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-28powerpc/eeh: No hotplug on permanently removed devGavin Shan
The issue was detected in a bit complicated test case where we have multiple hierarchical PEs shown as following figure: +-----------------+ | PE#3 p2p#0 | | p2p#1 | +-----------------+ | +-----------------+ | PE#4 pdev#0 | | pdev#1 | +-----------------+ PE#4 (have 2 PCI devices) is the child of PE#3, which has 2 p2p bridges. We accidentally had less-known scenario: PE#4 was removed permanently from the system because of permanent failure (e.g. exceeding the max allowd failure times in last hour), then we detects EEH errors on PE#3 and tried to recover it. However, eeh_dev instances for pdev#0/1 were not detached from PE#4, which was still connected to PE#3. All of that was because of the fact that we rely on count-based pcibios_release_device(), which isn't reliable enough. When doing recovery for PE#3, we still apply hotplug on PE#4 and pdev#0/1, which are not valid any more. Eventually, we run into kernel crash. The patch fixes above issue from two aspects. For unplug, we simply skip those permanently removed PE, whose state is (EEH_PE_STATE_ISOLATED && !EEH_PE_STATE_RECOVERING) and its frozen count should be greater than EEH_MAX_ALLOWED_FREEZES. For plug, we marked all permanently removed EEH devices with EEH_DEV_REMOVED and return 0xFF's on read its PCI config so that PCI core will omit them. Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-15powerpc/eeh: Add restore_config operationGavin Shan
After reset on the specific PE or PHB, we never configure AER correctly on PowerNV platform. We needn't care it on pSeries platform. The patch introduces additional EEH operation eeh_ops:: restore_config() so that we have chance to configure AER correctly for PowerNV platform. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-01-15powerpc: Delete non-required instances of include <linux/init.h>Paul Gortmaker
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. The one instance where we add an include for init.h covers off a case where that file was implicitly getting it from another header which itself didn't need it. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Don't use pci_dev during BAR restoreGavin Shan
While restoring BARs for one specific PCI device, the pci_dev instance should have been released. So it's not reliable to use the pci_dev instance on restoring BARs. However, we still need some information (e.g. PCIe capability position, header type) from the pci_dev instance. So we have to store those information to EEH device in advance. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Use partial hotplug for EEH unaware driversGavin Shan
When EEH error happens to one specific PE, some devices with drivers supporting EEH won't except hotplug on the device. However, there might have other deivces without driver, or with driver without EEH support. For the case, we need do partial hotplug in order to make sure that the PE becomes absolutely quite during reset. Otherise, the PE reset might fail and leads to failure of error recovery. The current code doesn't handle that 'mixed' case properly, it either uses the error callbacks to the drivers, or tries hotplug, but doesn't handle a PE (EEH domain) composed of a combination of the two. The patch intends to support so-called "partial" hotplug for EEH: Before we do reset, we stop and remove those PCI devices without EEH sensitive driver. The corresponding EEH devices are not detached from its PE, but with special flag. After the reset is done, those EEH devices with the special flag will be scanned one by one. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Use safe list traversal when walking EEH devicesGavin Shan
Currently, we're trasversing the EEH devices list using list_for_each_entry(). That's not safe enough because the EEH devices might be removed from its parent PE while doing iteration. The patch replaces that with list_for_each_entry_safe(). Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Keep PE during hotplugGavin Shan
When we do normal hotplug, the PE (shadow EEH structure) shouldn't be kept around. However, we need to keep it if the hotplug an artifial one caused by EEH errors recovery. Since we remove EEH device through the PCI hook pcibios_release_device(), the flag "purge_pe" passed to various functions is meaningless. So the patch removes the meaningless flag and introduce new flag "EEH_PE_KEEP" to save the PE while doing hotplug during EEH error recovery. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01powerpc/eeh: Check PCIe link after resetGavin Shan
After reset (e.g. complete reset) in order to bring the fenced PHB back, the PCIe link might not be ready yet. The patch intends to make sure the PCIe link is ready before accessing its subordinate PCI devices. The patch also fixes that wrong values restored to PCI_COMMAND register for PCI bridges. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-25powerpc/eeh: Remove eeh_mutexGavin Shan
Originally, eeh_mutex was introduced to protect the PE hierarchy tree and the attached EEH devices because EEH core was possiblly running with multiple threads to access the PE hierarchy tree. However, we now have only one kthread in EEH core. So we needn't the eeh_mutex and just remove it. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Trace time on first error for PEGavin Shan
We're not expecting that one specific PE got frozen for over 5 times in last hour. Otherwise, the PE will be removed from the system upon newly coming EEH errors. The patch introduces time stamp to trace the first error on specific PE in last hour and function to update that accordingly. Besides, the time stamp is recovered during PE hotplug path as we did for frozen count. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Trace PCI bus from PEGavin Shan
There're several types of PEs can be supported for now: PHB, Bus and Device dependent PE. For PCI bus dependent PE, tracing the corresponding PCI bus from PE (struct eeh_pe) would make the code more efficient. The patch also enables the retrieval of PCI bus based on the PCI bus dependent PE. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Make eeh_pe_get() publicGavin Shan
While processing EEH event interrupt from P7IOC, we need function to retrieve the PE according to the indicated EEH device. The patch makes function eeh_pe_get() public so that other source files can call it for that purpose. Also, the patch fixes referring to wrong BDF (Bus/Device/Function) address while searching PE in function __eeh_pe_get(). Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Make eeh_phb_pe_get() publicGavin Shan
One of the possible cases indicated by P7IOC interrupt is fenced PHB. For that case, we need fetch the PE corresponding to the PHB and disable the PHB and all subordinate PCI buses/devices, recover from the fenced state and eventually enable the whole PHB. We need one function to fetch the PHB PE outside eeh_pe.c and the patch is going to make eeh_phb_pe_get() public for that purpose. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Move common part to kernel directoryGavin Shan
The patch moves the common part of EEH core into arch/powerpc/kernel directory so that we needn't PPC_PSERIES while compiling POWERNV platform: * Move the EEH common part into arch/powerpc/kernel * Move the functions for PCI hotplug from pSeries platform to arch/powerpc/kernel/pci-hotplug.c * Move CONFIG_EEH from arch/powerpc/platforms/pseries/Kconfig to arch/powerpc/platforms/Kconfig * Adjust makefile accordingly Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>