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Kuppuswamy Sathyanarayanan acb748fdc5 PCI/AER: Clear MULTI_ERR_COR/UNCOR_RCV bits
[ Upstream commit 203926da2b ]

When a Root Port or Root Complex Event Collector receives an error Message
e.g., ERR_COR, it sets PCI_ERR_ROOT_COR_RCV in the Root Error Status
register and logs the Requester ID in the Error Source Identification
register.  If it receives a second ERR_COR Message before software clears
PCI_ERR_ROOT_COR_RCV, hardware sets PCI_ERR_ROOT_MULTI_COR_RCV and the
Requester ID is lost.

In the following scenario, PCI_ERR_ROOT_MULTI_COR_RCV was never cleared:

  - hardware receives ERR_COR message
  - hardware sets PCI_ERR_ROOT_COR_RCV
  - aer_irq() entered
  - aer_irq(): status = pci_read_config_dword(PCI_ERR_ROOT_STATUS)
  - aer_irq(): now status == PCI_ERR_ROOT_COR_RCV
  - hardware receives second ERR_COR message
  - hardware sets PCI_ERR_ROOT_MULTI_COR_RCV
  - aer_irq(): pci_write_config_dword(PCI_ERR_ROOT_STATUS, status)
  - PCI_ERR_ROOT_COR_RCV is cleared; PCI_ERR_ROOT_MULTI_COR_RCV is set
  - aer_irq() entered again
  - aer_irq(): status = pci_read_config_dword(PCI_ERR_ROOT_STATUS)
  - aer_irq(): now status == PCI_ERR_ROOT_MULTI_COR_RCV
  - aer_irq() exits because PCI_ERR_ROOT_COR_RCV not set
  - PCI_ERR_ROOT_MULTI_COR_RCV is still set

The same problem occurred with ERR_NONFATAL/ERR_FATAL Messages and
PCI_ERR_ROOT_UNCOR_RCV and PCI_ERR_ROOT_MULTI_UNCOR_RCV.

Fix the problem by queueing an AER event and clearing the Root Error Status
bits when any of these bits are set:

  PCI_ERR_ROOT_COR_RCV
  PCI_ERR_ROOT_UNCOR_RCV
  PCI_ERR_ROOT_MULTI_COR_RCV
  PCI_ERR_ROOT_MULTI_UNCOR_RCV

See the bugzilla link for details from Eric about how to reproduce this
problem.

[bhelgaas: commit log, move repro details to bugzilla]
Fixes: e167bfcaa4 ("PCI: aerdrv: remove magical ROOT_ERR_STATUS_MASKS")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215992
Link: https://lore.kernel.org/r/20220418150237.1021519-1-sathyanarayanan.kuppuswamy@linux.intel.com
Reported-by: Eric Badger <ebadger@purestorage.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:23:11 +02:00
arch ARM: dts: at91: sama7g5: remove interrupt-parent from gic node 2022-06-09 10:23:11 +02:00
block bfq: Allow current waker to defend against a tentative one 2022-06-09 10:23:01 +02:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto crypto: cryptd - Protect per-CPU resource by disabling BH. 2022-06-09 10:23:11 +02:00
Documentation sched/psi: report zeroes for CPU full at the system level 2022-06-09 10:22:48 +02:00
drivers PCI/AER: Clear MULTI_ERR_COR/UNCOR_RCV bits 2022-06-09 10:23:11 +02:00
fs hugetlbfs: fix hugetlbfs_statfs() locking 2022-06-09 10:23:11 +02:00
include list: fix a data-race around ep->rdllist 2022-06-09 10:23:09 +02:00
init random: handle latent entropy and command line from random_init() 2022-05-30 09:29:16 +02:00
ipc ipc/mqueue: use get_tree_nodev() in mqueue_get_tree() 2022-06-09 10:23:10 +02:00
kernel dma-direct: don't over-decrypt memory 2022-06-09 10:23:03 +02:00
lib kunit: fix debugfs code to use enum kunit_status, not bool 2022-06-09 10:22:53 +02:00
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mm zsmalloc: fix races between asynchronous zspage free and page migration 2022-06-06 08:43:39 +02:00
net net/smc: postpone sk_refcnt increment in connect() 2022-06-09 10:23:03 +02:00
samples samples: bpf: Don't fail for a missing VMLINUX_BTF when VMLINUX_H is provided 2022-06-09 10:22:55 +02:00
scripts scripts/faddr2line: Fix overlapping text section failures 2022-06-09 10:22:57 +02:00
security lockdown: also lock down previous kgdb use 2022-05-25 09:57:37 +02:00
sound ASoC: atmel-classd: Remove endianness flag on class d component 2022-06-09 10:23:10 +02:00
tools selftests/bpf: Add missed ima_setup.sh in Makefile 2022-06-09 10:23:00 +02:00
usr usr/include/Makefile: add linux/nfc.h to the compile-test coverage 2022-02-01 17:27:15 +01:00
virt KVM: avoid NULL pointer dereference in kvm_dirty_ring_push 2022-04-13 20:59:26 +02:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
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.mailmap mailmap: add Andrej Shadura 2021-10-18 20:22:03 -10:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: add git tree for random.c 2022-05-30 09:28:59 +02:00
Makefile Linux 5.15.45 2022-06-06 08:43:42 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.