No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Suravee Suthikulpanit 071f42defa iommu/amd: Use cmpxchg_double() when updating 128-bit IRTE
commit e52d58d54a321d4fe9d0ecdabe4f8774449f0d6e upstream.

When using 128-bit interrupt-remapping table entry (IRTE) (a.k.a GA mode),
current driver disables interrupt remapping when it updates the IRTE
so that the upper and lower 64-bit values can be updated safely.

However, this creates a small window, where the interrupt could
arrive and result in IO_PAGE_FAULT (for interrupt) as shown below.

  IOMMU Driver            Device IRQ
  ============            ===========
  irte.RemapEn=0
       ...
   change IRTE            IRQ from device ==> IO_PAGE_FAULT !!
       ...
  irte.RemapEn=1

This scenario has been observed when changing irq affinity on a system
running I/O-intensive workload, in which the destination APIC ID
in the IRTE is updated.

Instead, use cmpxchg_double() to update the 128-bit IRTE at once without
disabling the interrupt remapping. However, this means several features,
which require GA (128-bit IRTE) support will also be affected if cmpxchg16b
is not supported (which is unprecedented for AMD processors w/ IOMMU).

Fixes: 880ac60e25 ("iommu/amd: Introduce interrupt remapping ops structure")
Reported-by: Sean Osborne <sean.m.osborne@oracle.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Erik Rockstrom <erik.rockstrom@oracle.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20200903093822.52012-3-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-26 18:03:15 +02:00
arch powerpc/dma: Fix dma_map_ops::get_required_mask 2020-09-23 12:40:46 +02:00
block block: only call sched requeue_request() for scheduled requests 2020-09-23 12:40:37 +02:00
certs
crypto crypto: af_alg - Work around empty control messages without MSG_MORE 2020-09-03 11:27:05 +02:00
Documentation affs: fix basic permission bits to actually work 2020-09-09 19:12:34 +02:00
drivers iommu/amd: Use cmpxchg_double() when updating 128-bit IRTE 2020-09-26 18:03:15 +02:00
fs f2fs: Return EOF on unaligned end of file DIO read 2020-09-23 12:40:38 +02:00
include net: add __must_check to skb_put_padto() 2020-09-26 18:03:15 +02:00
init
ipc
kernel kprobes: fix kill kprobe which has been marked as gone 2020-09-26 18:03:11 +02:00
lib kobject: Restore old behaviour of kobject_del(NULL) 2020-09-17 13:47:52 +02:00
LICENSES
mm mm: memcg: fix memcg reclaim soft lockup 2020-09-26 18:03:15 +02:00
net net: qrtr: check skb_put_padto() return value 2020-09-26 18:03:15 +02:00
samples bpf: Fix fds_example SIGSEGV error 2020-08-19 08:16:03 +02:00
scripts checkpatch: fix the usage of capture group ( ... ) 2020-09-09 19:12:37 +02:00
security Smack: prevent underflow in smk_set_cipso() 2020-08-19 08:16:16 +02:00
sound ALSA: hda/realtek - The Mic on a RedmiBook doesn't work 2020-09-23 12:40:45 +02:00
tools selftests/vm: fix display of page size in map_hugetlb 2020-09-23 12:40:46 +02:00
usr
virt KVM: fix memory leak in kvm_io_bus_unregister_dev() 2020-09-17 13:47:54 +02:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS Documentation/llvm: add documentation on building w/ Clang/LLVM 2020-08-26 10:40:46 +02:00
Makefile Linux 5.4.67 2020-09-23 12:40:47 +02:00
README

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.