kernel.git/arch/powerpc/kernel/eeh_pe.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The EEH event handler thread processes the eeh_event and crashes since the eeh_pe pointer in the eeh_event structure is no longer valid.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 include_passed to eeh_pe_state_clear()

2019-02-05T00:55:43Z

Add a parameter to eeh_pe_state_clear() that allows passed-through PEs to be excluded. Update callers to always pass true so that there is no change in behaviour. Also refactor to use direct traversal, to allow the removal of some boilerplate. This is to prepare for follow-up work for passed-through devices. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman

powerpc/eeh: Cleanup eeh_ops.wait_state()

2018-10-13T11:21:25Z

The wait_state member of eeh_ops does not need to be platform dependent; it's just logic around eeh_ops.get_state(). Therefore, merge the two (slightly different!) platform versions into a new function, eeh_wait_state() and remove the eeh_ops member. While doing this, also correct: * The wait logic, so that it never waits longer than max_wait. * The wait logic, so that it never waits less than EEH_STATE_MIN_WAIT_TIME. * One call site where the result is treated like a bit field before it's checked for negative error values. * In pseries_eeh_get_state(), rename the "state" parameter to "delay" because that's what it is. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman

powerpc/eeh: Cleanup eeh_pe_state_mark()

2018-10-13T11:21:25Z

Currently, eeh_pe_state_mark() marks a PE (and it's children) with a state and then performs additional processing if that state included EEH_PE_ISOLATED. The state parameter is always a constant at the call site, so rearrange eeh_pe_state_mark() into two functions and just call the appropriate one at each site. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman

powerpc/eeh: Cleanup unnecessary eeh_pe_state_mark_with_cfg()

2018-10-13T11:21:25Z

The function eeh_pe_state_mark_with_cfg() just performs the work of eeh_pe_state_mark() and then, conditionally, the work of eeh_pe_state_clear(). However it is only ever called with a constant state such that the condition is always true, so replace it by direct calls. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman

powerpc/eeh: Cleanup logic in eeh_rmv_from_parent_pe()

2018-10-13T11:21:25Z

Move the call to eeh_dev_to_pe() up, so that later it's clear that "pe" isn't NULL. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman

powerpc/eeh: Cleanup list_head field names

2018-10-13T11:21:25Z

Instances of struct eeh_pe are placed in a tree structure using the fields "child_list" and "child", so place these next to each other in the definition. The field "child" is a list entry, so remove the unnecessary and misleading use of the list initializer, LIST_HEAD(), on it. The eeh_dev struct contains two list entry fields, called "list" and "rmv_list". Rename them to "entry" and "rmv_entry" and, as above, stop initializing them with LIST_HEAD(). Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman

powerpc/eeh: Fix use of EEH_PE_KEEP on wrong field

2018-10-13T11:21:25Z

eeh_add_to_parent_pe() sometimes removes the EEH_PE_KEEP flag, but it incorrectly removes it from pe->type, instead of pe->state. However, rather than clearing it from the correct field, remove it. Inspection of the code shows that it can't ever have had any effect (even if it had been cleared from the correct field), because the field is never tested after it is cleared by the statement in question. The clear statement was added by commit 807a827d4e74 ("powerpc/eeh: Keep PE during hotplug"), but it didn't explain why it was necessary. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman

powerpc/eeh: Introduce eeh_for_each_pe()

2018-06-03T10:43:39Z

Add a for_each-style macro for iterating through PEs without the boilerplate required by a traversal function. eeh_pe_next() is now exported, as it is now used directly in place. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman