kernel.git/arch/powerpc/kernel/eeh_event.c, branch linux-5.3.y

powerpc/eeh: Clean up EEH PEs after recovery finishes

2019-10-07T17:01:22Z

[ Upstream commit 799abe283e5103d48e079149579b4f167c95ea0e ] When the last device in an eeh_pe is removed the eeh_pe structure itself (and any empty parents) are freed since they are no longer needed. This results in a crash when a hotplug driver is involved since the following may occur: 1. Device is suprise removed. 2. Driver performs an MMIO, which fails and queues and eeh_event. 3. Hotplug driver receives a hotplug interrupt and removes any pci_devs that were under the slot. 4. pci_dev is torn down and the eeh_pe is freed. 5. The EEH event handler thread processes the eeh_event and crashes since the eeh_pe pointer in the eeh_event structure is no longer valid. Crashing is generally considered poor form. Instead of doing that use the fact PEs are marked as EEH_PE_INVALID to keep them around until the end of the recovery cycle, at which point we can safely prune any empty PEs. Signed-off-by: Oliver O'Halloran Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190903101605.2890-2-oohall@gmail.com Signed-off-by: Sasha Levin

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman

powerpc/eeh: Add eeh_force_recover to debugfs

2019-02-21T13:10:15Z

This patch adds a debugfs interface to force scheduling a recovery event. This can be used to recover a specific PE or schedule a "special" recovery even that checks for errors at the PHB level. To force a recovery of a normal PE, use: echo '<#pe>:<#phb>' > /sys/kernel/debug/powerpc/eeh_force_recover To force a scan for broken PHBs: echo 'hwcheck' > /sys/kernel/debug/powerpc/eeh_force_recover Signed-off-by: Oliver O'Halloran Signed-off-by: Michael Ellerman

powerpc/eeh: Allow disabling recovery

2019-02-21T13:10:14Z

Currently when we detect an error we automatically invoke the EEH recovery handler. This can be annoying when debugging EEH problems, or when working on EEH itself so this patch adds a debugfs knob that will prevent a recovery event from being queued up when an issue is detected. Signed-off-by: Oliver O'Halloran Signed-off-by: Michael Ellerman

powerpc: eeh_event: convert semaphore to completion

2018-12-20T11:21:20Z

For this use case, completions and semaphores are equivalent, but semaphores are an awkward interface that should generally be avoided, so use the completion instead. Signed-off-by: Arnd Bergmann Signed-off-by: Michael Ellerman

powerpc/eeh: Manage EEH_PE_RECOVERING inside eeh_handle_normal_event()

2018-03-27T12:44:58Z

Currently the EEH_PE_RECOVERING flag for a PE is managed by both the caller and callee of eeh_handle_normal_event() (among other places not considered here). This is complicated by the fact that the PE may or may not have been invalidated by the call. So move the callee's handling into eeh_handle_normal_event(), which clarifies it and allows the return type to be changed to void (because it no longer needs to indicate at the PE has been invalidated). This should not change behaviour except in eeh_event_handler() where it was previously possible to cause eeh_pe_state_clear() to be called on an invalid PE, which is now avoided. Signed-off-by: Sam Bobroff Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman

powerpc/eeh: Remove eeh_handle_event()

2018-03-27T12:44:57Z

The function eeh_handle_event(pe) does nothing other than switching between calling eeh_handle_normal_event(pe) and eeh_handle_special_event(). However it is only called in two places, one where pe can't be NULL and the other where it must be NULL (see eeh_event_handler()) so it does nothing but obscure the flow of control. So, remove it. Signed-off-by: Sam Bobroff Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman

powerpc/pci: Always print PHB and PE numbers as hexadecimal

2016-11-22T00:57:07Z

PHB, PE (and by association MVE) numbers are printed as a mix of decimal and hexadecimal throughout the kernel. This can be misleading, so make them all hexadecimal. Standardising on hex instead of dec because: - PHB numbers are presented in hex in sysfs/debugfs (and lspci, etc) - PE numbers are presented as hex in sysfs and parsed in hex in debugfs The only place I think this could cause confusing are the messages during boot, i.e. pci 000a:01 : [PE# 000] Secondary bus 1 associated with PE#0 which can be a quick way to check PE numbers. pe_level_printk() will only print two characters instead of three, so the above would be pci 000a:01 : [PE# 00] Secondary bus 1 associated with PE#0 which gives a hint it's in hex. Signed-off-by: Russell Currey Signed-off-by: Michael Ellerman

powerpc: sparse: static-ify some things

2016-04-12T11:05:18Z

As sparse suggests, these should be made static. Signed-off-by: Daniel Axtens Reviewed-by: Andrew Donnellan Reviewed-by: Stewart Smith Signed-off-by: Michael Ellerman

powerpc/powernv: Fix killed EEH event

2014-06-11T07:04:33Z

On PowerNV platform, EEH errors are reported by IO accessors or poller driven by interrupt. After the PE is isolated, we won't produce EEH event for the PE. The current implementation has possibility of EEH event lost in this way: The interrupt handler queues one "special" event, which drives the poller. EEH thread doesn't pick the special event yet. IO accessors kicks in, the frozen PE is marked as "isolated" and EEH event is queued to the list. EEH thread runs because of special event and purge all existing EEH events. However, we never produce an other EEH event for the frozen PE. Eventually, the PE is marked as "isolated" and we don't have EEH event to recover it. The patch fixes the issue to keep EEH events for PEs that have been marked as "isolated" with the help of additional "force" help to eeh_remove_event(). Reported-by: Rolf Brudeseth Signed-off-by: Gavin Shan Signed-off-by: Benjamin Herrenschmidt