linux.git/include/xen, branch v6.18.21

Partial revert "x86/xen: fix balloon target initialization for PVH dom0"

2026-02-26T22:59:01+00:00

[ Upstream commit 0949c646d64697428ff6257d52efa5093566868d ]

This partially reverts commit 87af633689ce16ddb166c80f32b120e50b1295de 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: 87af633689ce ("x86/xen: fix balloon target initialization for PVH dom0")
Reported-by: James Dingwall 
Signed-off-by: Roger Pau Monné 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Message-ID: <20260128110510.46425-2-roger.pau@citrix.com>
Signed-off-by: Sasha Levin

xen: replace XENFEAT_auto_translated_physmap with xen_pv_domain()

2025-09-08T15:01:36+00:00

Instead of testing the XENFEAT_auto_translated_physmap feature, just
use !xen_pv_domain() which is equivalent.

This has the advantage that a kernel not built with CONFIG_XEN_PV
will be smaller due to dead code elimination.

Reviewed-by: Jason Andryuk 
Signed-off-by: Juergen Gross 
Message-ID: <20250826145608.10352-3-jgross@suse.com>

xen: rework xen_pv_domain()

2025-09-08T15:01:36+00:00

Rework xen_pv_domain() to no longer use the xen_domain_type variable,
but the artificial X86_FEATURE_XENPV cpu feature.

On non-x86 architectures xen_pv_domain() can be defined as "0".

This has the advantage that a kernel not built with CONFIG_XEN_PV
will be smaller due to dead code elimination.

Set the X86_FEATURE_XENPV feature very early, as xen_pv_domain() is
used rather early, too.

Reviewed-by: Jason Andryuk 
Signed-off-by: Juergen Gross 
Message-ID: <20250826145608.10352-2-jgross@suse.com>

Merge tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-08-03T23:23:09+00:00

Pull non-MM updates from Andrew Morton:
 "Significant patch series in this pull request:

   - "squashfs: Remove page->mapping references" (Matthew Wilcox) gets
     us closer to being able to remove page->mapping

   - "relayfs: misc changes" (Jason Xing) does some maintenance and
     minor feature addition work in relayfs

   - "kdump: crashkernel reservation from CMA" (Jiri Bohac) switches
     us from static preallocation of the kdump crashkernel's working
     memory over to dynamic allocation. So the difficulty of a-priori
     estimation of the second kernel's needs is removed and the first
     kernel obtains extra memory

   - "generalize panic_print's dump function to be used by other
     kernel parts" (Feng Tang) implements some consolidation and
     rationalization of the various ways in which a failing kernel
     splats information at the operator

* tag 'mm-nonmm-stable-2025-08-03-12-47' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (80 commits)
  tools/getdelays: add backward compatibility for taskstats version
  kho: add test for kexec handover
  delaytop: enhance error logging and add PSI feature description
  samples: Kconfig: fix spelling mistake "instancess" -> "instances"
  fat: fix too many log in fat_chain_add()
  scripts/spelling.txt: add notifer||notifier to spelling.txt
  xen/xenbus: fix typo "notifer"
  net: mvneta: fix typo "notifer"
  drm/xe: fix typo "notifer"
  cxl: mce: fix typo "notifer"
  KVM: x86: fix typo "notifer"
  MAINTAINERS: add maintainers for delaytop
  ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below()
  ucount: fix atomic_long_inc_below() argument type
  kexec: enable CMA based contiguous allocation
  stackdepot: make max number of pools boot-time configurable
  lib/xxhash: remove unused functions
  init/Kconfig: restore CONFIG_BROKEN help text
  lib/raid6: update recov_rvv.c zero page usage
  docs: update docs after introducing delaytop
  ...

xen/xenbus: fix typo "notifer"

2025-08-02T19:01:40+00:00

There is a spelling mistake of 'notifer' in the comment which
should be 'notifier'.

Link: https://lkml.kernel.org/r/C6633C66376C709A+20250722073431.21983-7-wangyuli@uniontech.com
Signed-off-by: WangYuli 
Reviewed-by: Juergen Gross 
Signed-off-by: Andrew Morton

xen: Remove some deadcode (x)

2025-07-14T07:55:52+00:00

Remove three uncalled functions:

  xenbus_mkdir() was added in 2007 by
commit 4bac07c993d0 ("xen: add the Xenbus sysfs and virtual device hotplug
driver")
but has remained unused.

  xen_get_runstate_snapshot() last use was removed in 2016 by
commit 6ba286ad8457 ("xen: support runqueue steal time on xen")
which replaces the use by the _cpu version.

  xen_resume_notifier_unregister() last use was removed in 2017 by
commit 1914f0cd203c ("xen/acpi: upload PM state from init-domain to Xen")

Remove them.

Signed-off-by: "Dr. David Alan Gilbert" 
Reviewed-by: Juergen Gross 
Signed-off-by: Juergen Gross 
Message-ID: <20250713132625.164728-1-linux@treblig.org>

xen/mcelog: Add __nonstring annotations for unterminated strings

2025-03-14T10:15:16+00:00

When a character array without a terminating NUL character has a static
initializer, GCC 15's -Wunterminated-string-initialization will only
warn if the array lacks the "nonstring" attribute[1]. Mark the arrays
with __nonstring to and correctly identify the char array as "not a C
string" and thereby eliminate the warning.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178 [1]
Cc: Juergen Gross 
Cc: Stefano Stabellini 
Cc: Oleksandr Tyshchenko 
Cc: xen-devel@lists.xenproject.org
Signed-off-by: Kees Cook 
Acked-by: Juergen Gross 
Message-ID: <20250310222234.work.473-kees@kernel.org>
Signed-off-by: Juergen Gross

xen: Remove dependency between pciback and privcmd

2024-10-18T09:59:04+00:00

Commit 2fae6bb7be32 ("xen/privcmd: Add new syscall to get gsi from dev")
adds a weak reverse dependency to the config XEN_PRIVCMD definition, that
dependency causes xen-privcmd can't be loaded on domU, because dependent
xen-pciback isn't always be loaded successfully on domU.

To solve above problem, remove that dependency, and do not call
pcistub_get_gsi_from_sbdf() directly, instead add a hook in
drivers/xen/apci.c, xen-pciback register the real call function, then in
privcmd_ioctl_pcidev_get_gsi call that hook.

Fixes: 2fae6bb7be32 ("xen/privcmd: Add new syscall to get gsi from dev")
Reported-by: Marek Marczykowski-Górecki 
Signed-off-by: Jiqian Chen 
Reviewed-by: Juergen Gross 
Message-ID: <20241012084537.1543059-1-Jiqian.Chen@amd.com>
Signed-off-by: Juergen Gross

xen: sync elfnote.h from xen tree

2024-09-25T12:15:04+00:00

Sync Xen's elfnote.h header from xen.git to pull in the
XEN_ELFNOTE_PHYS32_RELOC define.

xen commit dfc9fab00378 ("x86/PVH: Support relocatable dom0 kernels")

This is a copy except for the removal of the emacs editor config at the
end of the file.

Signed-off-by: Jason Andryuk 
Reviewed-by: Juergen Gross 
Message-ID: <20240823193630.2583107-2-jason.andryuk@amd.com>
Signed-off-by: Juergen Gross

xen/privcmd: Add new syscall to get gsi from dev

2024-09-25T07:54:55+00:00

On PVH dom0, when passthrough a device to domU, QEMU and xl tools
want to use gsi number to do pirq mapping, see QEMU code
xen_pt_realize->xc_physdev_map_pirq, and xl code
pci_add_dm_done->xc_physdev_map_pirq, but in current codes, the gsi
number is got from file /sys/bus/pci/devices//irq, that is
wrong, because irq is not equal with gsi, they are in different
spaces, so pirq mapping fails.
And in current linux codes, there is no method to get gsi
for userspace.

For above purpose, record gsi of pcistub devices when init
pcistub and add a new syscall into privcmd to let userspace
can get gsi when they have a need.

Signed-off-by: Jiqian Chen 
Signed-off-by: Huang Rui 
Signed-off-by: Jiqian Chen 
Reviewed-by: Stefano Stabellini 
Message-ID: <20240924061437.2636766-4-Jiqian.Chen@amd.com>
Signed-off-by: Juergen Gross