Kernel Source and devicetree for NOTHING Phone(3a) and Phone(3a)Pro
Find a file
Haitao Shan 7545ddda9c KVM: x86: Fix lapic timer interrupt lost after loading a snapshot.
[ Upstream commit 9cfec6d097c607e36199cf0cfbb8cf5acbd8e9b2 ]

When running android emulator (which is based on QEMU 2.12) on
certain Intel hosts with kernel version 6.3-rc1 or above, guest
will freeze after loading a snapshot. This is almost 100%
reproducible. By default, the android emulator will use snapshot
to speed up the next launching of the same android guest. So
this breaks the android emulator badly.

I tested QEMU 8.0.4 from Debian 12 with an Ubuntu 22.04 guest by
running command "loadvm" after "savevm". The same issue is
observed. At the same time, none of our AMD platforms is impacted.
More experiments show that loading the KVM module with
"enable_apicv=false" can workaround it.

The issue started to show up after commit 8e6ed96cdd50 ("KVM: x86:
fire timer when it is migrated and expired, and in oneshot mode").
However, as is pointed out by Sean Christopherson, it is introduced
by commit 967235d320 ("KVM: vmx: clear pending interrupts on
KVM_SET_LAPIC"). commit 8e6ed96cdd50 ("KVM: x86: fire timer when
it is migrated and expired, and in oneshot mode") just makes it
easier to hit the issue.

Having both commits, the oneshot lapic timer gets fired immediately
inside the KVM_SET_LAPIC call when loading the snapshot. On Intel
platforms with APIC virtualization and posted interrupt processing,
this eventually leads to setting the corresponding PIR bit. However,
the whole PIR bits get cleared later in the same KVM_SET_LAPIC call
by apicv_post_state_restore. This leads to timer interrupt lost.

The fix is to move vmx_apicv_post_state_restore to the beginning of
the KVM_SET_LAPIC call and rename to vmx_apicv_pre_state_restore.
What vmx_apicv_post_state_restore does is actually clearing any
former apicv state and this behavior is more suitable to carry out
in the beginning.

Fixes: 967235d320 ("KVM: vmx: clear pending interrupts on KVM_SET_LAPIC")
Cc: stable@vger.kernel.org
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Haitao Shan <hshan@google.com>
Link: https://lore.kernel.org/r/20230913000215.478387-1-hshan@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-08 08:51:18 +01:00
arch KVM: x86: Fix lapic timer interrupt lost after loading a snapshot. 2023-12-08 08:51:18 +01:00
block blk-core: use pr_warn_ratelimited() in bio_check_ro() 2023-11-20 11:52:17 +01:00
certs certs: Fix build error when PKCS#11 URI contains semicolon 2023-02-09 11:28:11 +01:00
crypto crypto: pcrypt - Fix hungtask for PADATA_RESET 2023-11-28 17:06:58 +00:00
Documentation smp,csd: Throw an error if a CSD lock is stuck for too long 2023-11-28 17:06:55 +00:00
drivers net: ravb: Keep reverse order of operations in ravb_remove() 2023-12-08 08:51:18 +01:00
fs btrfs: fix 64bit compat send ioctl arguments not initializing version member 2023-12-08 08:51:16 +01:00
include uapi: propagate __struct_group() attributes to the container union 2023-12-08 08:51:17 +01:00
init proc: sysctl: prevent aliased sysctls from getting passed to init 2023-11-28 17:07:08 +00:00
io_uring io_uring: fix off-by one bvec index 2023-12-03 07:32:13 +01:00
ipc ipc: fix memory leak in init_mqueue_fs() 2022-12-31 13:32:01 +01:00
kernel lockdep: Fix block chain corruption 2023-12-03 07:32:09 +01:00
lib parisc: Drop the HP-UX ENOSYM and EREMOTERELEASE error codes 2023-12-08 08:51:15 +01:00
LICENSES
mm mm,kfence: decouple kfence from page granularity mapping judgement 2023-12-03 07:32:08 +01:00
net ipv4: igmp: fix refcnt uaf issue when receiving igmp query packet 2023-12-08 08:51:17 +01:00
rust rust: allocator: Prevent mis-aligned allocation 2023-08-11 12:08:18 +02:00
samples fprobe: Pass entry_data to handlers 2023-10-25 12:03:12 +02:00
scripts randstruct: Fix gcc-plugin performance mode to stay in group 2023-11-28 17:07:07 +00:00
security ima: detect changes to the backing overlay file 2023-11-28 17:07:12 +00:00
sound ALSA: hda/realtek: Add supported ALC257 for ChromeOS 2023-12-08 08:51:13 +01:00
tools selftests/net: mptcp: fix uninitialized variable warnings 2023-12-08 08:51:17 +01:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt kvm/vfio: ensure kvg instance stays around in kvm_vfio_group_add() 2023-09-13 09:42:46 +02:00
.clang-format inet: ping: use hlist_nulls rcu iterator during lookup 2022-12-01 12:42:46 +01:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes
.gitignore Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap 9 hotfixes. 6 for MM, 3 for other areas. Four of these patches address 2022-12-10 17:10:52 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig
MAINTAINERS devlink: move code to a dedicated directory 2023-08-30 16:11:00 +02:00
Makefile Linux 6.1.65 2023-12-03 07:32:13 +01:00
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.