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Kernel for Galaxy S24, rebased on CLO sources (WIP)
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Paolo Bonzini 493d556278 KVM: x86/pmu: fix masking logic for MSR_CORE_PERF_GLOBAL_CTRL 
commit 971079464001c6856186ca137778e534d983174a upstream.

When commit c59a1f106f ("KVM: x86/pmu: Add IA32_PEBS_ENABLE
MSR emulation for extended PEBS") switched the initialization of
cpuc->guest_switch_msrs to use compound literals, it screwed up
the boolean logic:

+	u64 pebs_mask = cpuc->pebs_enabled & x86_pmu.pebs_capable;
...
-	arr[0].guest = intel_ctrl & ~cpuc->intel_ctrl_host_mask;
-	arr[0].guest &= ~(cpuc->pebs_enabled & x86_pmu.pebs_capable);
+               .guest = intel_ctrl & (~cpuc->intel_ctrl_host_mask | ~pebs_mask),

Before the patch, the value of arr[0].guest would have been intel_ctrl &
~cpuc->intel_ctrl_host_mask & ~pebs_mask.  The intent is to always treat
PEBS events as host-only because, while the guest runs, there is no way
to tell the processor about the virtual address where to put PEBS records
intended for the host.

Unfortunately, the new expression can be expanded to

	(intel_ctrl & ~cpuc->intel_ctrl_host_mask) | (intel_ctrl & ~pebs_mask)

which makes no sense; it includes any bit that isn't *both* marked as
exclude_guest and using PEBS.  So, reinstate the old logic.  Another
way to write it could be "intel_ctrl & ~(cpuc->intel_ctrl_host_mask |
pebs_mask)", presumably the intention of the author of the faulty.
However, I personally find the repeated application of A AND NOT B to
be a bit more readable.

This shows up as guest failures when running concurrent long-running
perf workloads on the host, and was reported to happen with rcutorture.
All guests on a given host would die simultaneously with something like an
instruction fault or a segmentation violation.

Reported-by: Paul E. McKenney <paulmck@kernel.org>
Analyzed-by: Sean Christopherson <seanjc@google.com>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Fixes: c59a1f106f ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-10 17:10:21 +01:00
arch KVM: x86/pmu: fix masking logic for MSR_CORE_PERF_GLOBAL_CTRL 2024-01-10 17:10:21 +01:00
block block: Don't invalidate pagecache for invalid falloc modes 2024-01-10 17:10:20 +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 dt-bindings: nvmem: mxs-ocotp: Document fsl,ocotp 2024-01-01 12:39:04 +00:00
drivers drm/mgag200: Fix gamma lut not initialized for G200ER, G200EV, G200SE 2024-01-10 17:10:21 +01:00
fs cifs: do not depend on release_iface for maintaining iface_list 2024-01-10 17:10:21 +01:00
include kallsyms: Make module_kallsyms_on_each_symbol generally available 2024-01-05 15:18:40 +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 mutex_unlock with unreferenced ctx 2023-12-13 18:39:18 +01:00
ipc ipc: fix memory leak in init_mqueue_fs() 2022-12-31 13:32:01 +01:00
kernel tracing/kprobes: Fix symbol counting logic by looking at modules as well 2024-01-05 15:18:40 +01:00
lib lib/vsprintf: Fix %pfwf when current node refcount == 0 2024-01-01 12:39:07 +00:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm mm/memory-failure: check the mapcount of the precise page 2024-01-05 15:18:39 +01:00
net mptcp: prevent tcp diag from closing listener subflows 2024-01-10 17:10:20 +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 sign-file: Fix incorrect return values check 2023-12-20 17:00:19 +01:00
security keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry 2024-01-01 12:38:58 +00:00
sound ALSA: hda/realtek: Fix mute and mic-mute LEDs for HP ProBook 440 G6 2024-01-10 17:10:20 +01:00
tools selftests: mptcp: join: fix subflow_send_ack lookup 2024-01-01 12:39:06 +00:00
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 scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.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 COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
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 kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS devlink: move code to a dedicated directory 2023-08-30 16:11:00 +02:00
Makefile Linux 6.1.71 2024-01-05 15:18:41 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.