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James Morse 204f38310f KVM: arm64: Defer guest entry when an asynchronous exception is pending
commit 5dcd0fdbb4 upstream.

SError that occur during world-switch's entry to the guest will be
accounted to the guest, as the exception is masked until we enter the
guest... but we want to attribute the SError as precisely as possible.

Reading DISR_EL1 before guest entry requires free registers, and using
ESB+DISR_EL1 to consume and read back the ESR would leave KVM holding
a host SError... We would rather leave the SError pending and let the
host take it once we exit world-switch. To do this, we need to defer
guest-entry if an SError is pending.

Read the ISR to see if SError (or an IRQ) is pending. If so fake an
exit. Place this check between __guest_enter()'s save of the host
registers, and restore of the guest's. SError that occur between
here and the eret into the guest must have affected the guest's
registers, which we can naturally attribute to the guest.

The dsb is needed to ensure any previous writes have been done before
we read ISR_EL1. On systems without the v8.2 RAS extensions this
doesn't give us anything as we can't contain errors, and the ESR bits
to describe the severity are all implementation-defined. Replace
this with a nop for these systems.

Cc: stable@vger.kernel.org # v4.19
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-09 19:04:31 +02:00
arch KVM: arm64: Defer guest entry when an asynchronous exception is pending 2020-09-09 19:04:31 +02:00
block blk-mq: order adding requests to hctx->dispatch and checking SCHED_RESTART 2020-09-03 11:24:26 +02:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: af_alg - fix use-after-free in af_alg_accept() due to bh_lock_sock() 2020-07-09 09:37:10 +02:00
Documentation affs: fix basic permission bits to actually work 2020-09-09 19:04:30 +02:00
drivers dm thin metadata: Avoid returning cmd->bm wild pointer on error 2020-09-09 19:04:31 +02:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs affs: fix basic permission bits to actually work 2020-09-09 19:04:30 +02:00
include libata: implement ATA_HORKAGE_MAX_TRIM_128M and apply to Sandisks 2020-09-09 19:04:31 +02:00
init printk: queue wake_up_klogd irq_work only if per-CPU areas are ready 2020-07-22 09:32:13 +02:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-20 08:18:40 +02:00
kernel genirq/matrix: Deal with the sillyness of for_each_cpu() on UP 2020-09-03 11:24:29 +02:00
lib test_kmod: avoid potential double free in trigger_config_run_type() 2020-08-21 11:05:38 +02:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm: slub: fix conversion of freelist_corrupted() 2020-09-09 19:04:31 +02:00
net netfilter: nfnetlink: nfnetlink_unicast() reports EAGAIN instead of ENOBUFS 2020-09-09 19:04:26 +02:00
samples samples: bpf: Fix build error 2020-06-03 08:19:31 +02:00
scripts kconfig: qconf: fix signal connection to invalid slots 2020-08-26 10:31:04 +02:00
security Smack: prevent underflow in smk_set_cipso() 2020-08-19 08:14:59 +02:00
sound ALSA: hda - Fix silent audio output and corrupted input on MSI X570-A PRO 2020-09-09 19:04:30 +02:00
tools perf jevents: Fix suspicious code in fixregex() 2020-09-09 19:04:27 +02:00
usr initramfs: restore default compression behavior 2020-04-13 10:44:59 +02:00
virt KVM: arm64: Only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is not set 2020-08-26 10:31:07 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Update drm/i915 bug filing URL 2020-02-28 16:38:49 +01:00
Makefile Linux 4.19.143 2020-09-03 11:24:31 +02:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.