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Roger Pau Monne 0949c646d6 Partial revert "x86/xen: fix balloon target initialization for PVH dom0"
This partially reverts commit 87af633689 so
the current memory target for PV guests is still fetched from
start_info->nr_pages, which matches exactly what the toolstack sets the
initial memory target to.

Using get_num_physpages() is possible on PV also, but needs adjusting to
take into account the ISA hole and the PFN at 0 not considered usable
memory despite being populated, and hence would need extra adjustments.
Instead of carrying those extra adjustments switch back to the previous
code.  That leaves Linux with a difference in how current memory target is
obtained for HVM vs PV, but that's better than adding extra logic just for
PV.

However if switching to start_info->nr_pages for PV domains we need to
differentiate between released pages (freed back to the hypervisor) as
opposed to pages in the physmap which are not populated to start with.
Introduce a new xen_unpopulated_pages to account for papges that have
never been populated, and hence in the PV case don't need subtracting.

Fixes: 87af633689 ("x86/xen: fix balloon target initialization for PVH dom0")
Reported-by: James Dingwall <james@dingwall.me.uk>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260128110510.46425-2-roger.pau@citrix.com>
2026-02-02 07:31:22 +01:00
arch Partial revert "x86/xen: fix balloon target initialization for PVH dom0" 2026-02-02 07:31:22 +01:00
block block-6.19-20260109 2026-01-09 15:42:46 -10:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: seqiv - Do not use req->iv after crypto_aead_encrypt 2025-12-19 14:47:06 +08:00
Documentation xen: introduce xen_console_io option 2026-01-14 14:43:57 +01:00
drivers Partial revert "x86/xen: fix balloon target initialization for PVH dom0" 2026-02-02 07:31:22 +01:00
fs treewide: Update email address 2026-01-11 06:09:11 -10:00
include Partial revert "x86/xen: fix balloon target initialization for PVH dom0" 2026-02-02 07:31:22 +01:00
init Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
io_uring io_uring-6.19-20260109 2026-01-09 15:21:15 -10:00
ipc Significant patch series in this pull request: 2025-12-06 14:01:20 -08:00
kernel Fix a crash in sched_mm_cid_after_execve(). 2026-01-11 07:11:53 -10:00
lib Crypto library fixes for v6.19-rc5 2026-01-11 15:07:56 -10:00
LICENSES LICENSES: Add modern form of the LGPL-2.1 tags to the usage guide section 2025-10-22 07:58:19 +02:00
mm mm/ksm: fix pte_unmap_unlock of wrong address in break_ksm_pmd_entry 2025-12-23 11:23:17 -08:00
net A bunch of libceph fixes split evenly between memory safety and 2026-01-09 15:05:19 -10:00
rust Driver core fixes for 6.19-rc5 2026-01-10 15:04:04 -10:00
samples samples/ftrace: Adjust LoongArch register restore order in direct calls 2025-12-31 15:19:25 +08:00
scripts Crypto library fixes for v6.19-rc5 2026-01-11 15:07:56 -10:00
security kernel/kexec: change the prototype of kimage_map_segment() 2025-12-23 11:23:13 -08:00
sound ALSA: hda/realtek: add HP Laptop 15s-eq1xxx mute LED quirk 2026-01-02 14:34:23 +01:00
tools treewide: Update email address 2026-01-11 06:09:11 -10:00
usr initramfs: add gen_init_cpio to hostprogs unconditionally 2025-11-26 21:55:40 +01:00
virt KVM fixes for 6.19-rc1 2025-12-18 18:38:45 +01:00
.clang-format s390/pci: Fix cyclic dead-lock in zpci_zdev_put() and zpci_scan_devices() 2025-12-14 11:03:58 +01:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: kbuild: add proc macro library support 2025-11-24 17:15:36 +01:00
.mailmap treewide: Update email address 2026-01-11 06:09:11 -10:00
.pylintrc docs: Move the python libraries to tools/lib/python 2025-11-18 09:22:40 -07:00
.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 treewide: Update email address 2026-01-11 06:09:11 -10:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS Crypto library fixes for v6.19-rc5 2026-01-11 15:07:56 -10:00
Makefile Linux 6.19-rc5 2026-01-11 17:03:14 -10:00
README README: restructure with role-based documentation and guidelines 2025-11-29 08:40:33 -07:00

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

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst



Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst