1
Commit Graph

178 Commits

Author SHA1 Message Date
Juergen Gross
bf56c41016 x86/xen: mark boot CPU of PV guest in MSR_IA32_APICBASE
Recent topology checks of the x86 boot code uncovered the need for
PV guests to have the boot cpu marked in the APICBASE MSR.

Fixes: 9d22c96316 ("x86/topology: Handle bogus ACPI tables correctly")
Reported-by: Niels Dettenbach <nd@syndicat.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Juergen Gross <jgross@suse.com>
2024-10-08 16:18:57 +02:00
Juergen Gross
bcea31e2d1 x86/xen: eliminate some private header files
Under arch/x86/xen there is one large private header file xen-ops.h
containing most of the Xen-private x86 related declarations, and then
there are several small headers with a handful of declarations each.

Merge the small headers into xen-ops.h.

While doing that, move the declaration of xen_fifo_events from
xen-ops.h into include/xen/events.h where it should have been from the
beginning.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <20240710093718.14552-3-jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2024-07-11 16:33:48 +02:00
Juergen Gross
802600ebdf x86/xen: return a sane initial apic id when running as PV guest
With recent sanity checks for topology information added, there are now
warnings issued for APs when running as a Xen PV guest:

  [Firmware Bug]: CPU   1: APIC ID mismatch. CPUID: 0x0000 APIC: 0x0001

This is due to the initial APIC ID obtained via CPUID for PV guests is
always 0.

Avoid the warnings by synthesizing the CPUID data to contain the same
initial APIC ID as xen_pv_smp_config() is using for registering the
APIC IDs of all CPUs.

Fixes: 52128a7a21 ("86/cpu/topology: Make the APIC mismatch warnings complete")
Signed-off-by: Juergen Gross <jgross@suse.com>
2024-05-02 19:18:44 +02:00
Thomas Gleixner
c8f808231f x86/xen/smp_pv: Count number of vCPUs early
XEN/PV has a completely broken vCPU enumeration scheme, which just works by
chance and provides zero topology information. Each vCPU ends up being a
single core package.

Dom0 provides MADT which can be used for topology information, but that
table is the unmodified host table, which means that there can be more CPUs
registered than the number of vCPUs XEN provides for the dom0 guest.

DomU does not have ACPI and both rely on counting the possible vCPUs via an
hypercall.

To prepare for using CPUID topology information either via MADT or via fake
APIC IDs count the number of possible CPUs during early boot and adjust
nr_cpu_ids() accordingly.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kelley <mhklinux@outlook.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Link: https://lore.kernel.org/r/20240213210252.571795063@linutronix.de
2024-02-15 22:07:44 +01:00
Thomas Gleixner
be5341eb0d x86/entry: Convert INT 0x80 emulation to IDTENTRY
There is no real reason to have a separate ASM entry point implementation
for the legacy INT 0x80 syscall emulation on 64-bit.

IDTENTRY provides all the functionality needed with the only difference
that it does not:

  - save the syscall number (AX) into pt_regs::orig_ax
  - set pt_regs::ax to -ENOSYS

Both can be done safely in the C code of an IDTENTRY before invoking any of
the syscall related functions which depend on this convention.

Aside of ASM code reduction this prepares for detecting and handling a
local APIC injected vector 0x80.

[ kirill.shutemov: More verbose comments ]
Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@vger.kernel.org> # v6.0+
2023-12-07 09:51:29 -08:00
Juergen Gross
49147beb0c x86/xen: allow nesting of same lazy mode
When running as a paravirtualized guest under Xen, Linux is using
"lazy mode" for issuing hypercalls which don't need to take immediate
effect in order to improve performance (examples are e.g. multiple
PTE changes).

There are two different lazy modes defined: MMU and CPU lazy mode.
Today it is not possible to nest multiple lazy mode sections, even if
they are of the same kind. A recent change in memory management added
nesting of MMU lazy mode sections, resulting in a regression when
running as Xen PV guest.

Technically there is no reason why nesting of multiple sections of the
same kind of lazy mode shouldn't be allowed. So add support for that
for fixing the regression.

Fixes: bcc6cc8325 ("mm: add default definition of set_ptes()")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20230913113828.18421-4-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-09-19 07:04:49 +02:00
Juergen Gross
a4a7644c15 x86/xen: move paravirt lazy code
Only Xen is using the paravirt lazy mode code, so it can be moved to
Xen specific sources.

This allows to make some of the functions static or to merge them into
their only call sites.

While at it do a rename from "paravirt" to "xen" for all moved
specifiers.

No functional change.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20230913113828.18421-3-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-09-19 07:04:49 +02:00
Linus Torvalds
df57721f9a Add x86 shadow stack support
Convert IBT selftest to asm to fix objtool warning
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmTv1QQACgkQaDWVMHDJ
 krAUwhAAn6TOwHJK8BSkHeiQhON1nrlP3c5cv0AyZ2NP8RYDrZrSZvhpYBJ6wgKC
 Cx5CGq5nn9twYsYS3KsktLKDfR3lRdsQ7K9qtyFtYiaeaVKo+7gEKl/K+klwai8/
 gninQWHk0zmSCja8Vi77q52WOMkQKapT8+vaON9EVDO8dVEi+CvhAIfPwMafuiwO
 Rk4X86SzoZu9FP79LcCg9XyGC/XbM2OG9eNUTSCKT40qTTKm5y4gix687NvAlaHR
 ko5MTsdl0Wfp6Qk0ohT74LnoA2c1g/FluvZIM33ci/2rFpkf9Hw7ip3lUXqn6CPx
 rKiZ+pVRc0xikVWkraMfIGMJfUd2rhelp8OyoozD7DB7UZw40Q4RW4N5tgq9Fhe9
 MQs3p1v9N8xHdRKl365UcOczUxNAmv4u0nV5gY/4FMC6VjldCl2V9fmqYXyzFS4/
 Ogg4FSd7c2JyGFKPs+5uXyi+RY2qOX4+nzHOoKD7SY616IYqtgKoz5usxETLwZ6s
 VtJOmJL0h//z0A7tBliB0zd+SQ5UQQBDC2XouQH2fNX2isJMn0UDmWJGjaHgK6Hh
 8jVp6LNqf+CEQS387UxckOyj7fu438hDky1Ggaw4YqowEOhQeqLVO4++x+HITrbp
 AupXfbJw9h9cMN63Yc0gVxXQ9IMZ+M7UxLtZ3Cd8/PVztNy/clA=
 =3UUm
 -----END PGP SIGNATURE-----

Merge tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 shadow stack support from Dave Hansen:
 "This is the long awaited x86 shadow stack support, part of Intel's
  Control-flow Enforcement Technology (CET).

  CET consists of two related security features: shadow stacks and
  indirect branch tracking. This series implements just the shadow stack
  part of this feature, and just for userspace.

  The main use case for shadow stack is providing protection against
  return oriented programming attacks. It works by maintaining a
  secondary (shadow) stack using a special memory type that has
  protections against modification. When executing a CALL instruction,
  the processor pushes the return address to both the normal stack and
  to the special permission shadow stack. Upon RET, the processor pops
  the shadow stack copy and compares it to the normal stack copy.

  For more information, refer to the links below for the earlier
  versions of this patch set"

Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/
Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/

* tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
  x86/shstk: Change order of __user in type
  x86/ibt: Convert IBT selftest to asm
  x86/shstk: Don't retry vm_munmap() on -EINTR
  x86/kbuild: Fix Documentation/ reference
  x86/shstk: Move arch detail comment out of core mm
  x86/shstk: Add ARCH_SHSTK_STATUS
  x86/shstk: Add ARCH_SHSTK_UNLOCK
  x86: Add PTRACE interface for shadow stack
  selftests/x86: Add shadow stack test
  x86/cpufeatures: Enable CET CR4 bit for shadow stack
  x86/shstk: Wire in shadow stack interface
  x86: Expose thread features in /proc/$PID/status
  x86/shstk: Support WRSS for userspace
  x86/shstk: Introduce map_shadow_stack syscall
  x86/shstk: Check that signal frame is shadow stack mem
  x86/shstk: Check that SSP is aligned on sigreturn
  x86/shstk: Handle signals for shadow stack
  x86/shstk: Introduce routines modifying shstk
  x86/shstk: Handle thread shadow stack
  x86/shstk: Add user-mode shadow stack support
  ...
2023-08-31 12:20:12 -07:00
Linus Torvalds
1687d8aca5 * Rework apic callbacks, getting rid of unnecessary ones and
coalescing lots of silly duplicates.
  * Use static_calls() instead of indirect calls for apic->foo()
  * Tons of cleanups an crap removal along the way
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEV76QKkVc4xCGURexaDWVMHDJkrAFAmTvfO8ACgkQaDWVMHDJ
 krAP2A//ccii/LuvtTnNEIMMR5w2rwTdHv91ancgFkC8pOeNk37Z8sSLq8tKuLFA
 vgjBIysVIqunuRcNCJ+eqwIIxYfU+UGCWHppzLwO+DY3Q7o9EoTL0BgytdAqxpQQ
 ntEVarqWq25QYXKFoAqbUTJ1UXa42/8HfiXAX/jvP+ACXfilkGPZre6ASxlXeOhm
 XbgPuNQPmXi2WYQH9GCQEsz2Nh80hKap8upK2WbQzzJ3lXsm+xA//4klab0HCYwl
 Uc302uVZozyXRMKbAlwmgasTFOLiV8KKriJ0oHoktBpWgkpdR9uv/RDeSaFR3DAl
 aFmecD4k/Hqezg4yVl+4YpEn2KjxiwARCm4PMW5AV7lpWBPBHAOOai65yJlAi9U6
 bP8pM0+aIx9xg7oWfsTnQ7RkIJ+GZ0w+KZ9LXFM59iu3eV1pAJE3UVyUehe/J1q9
 n8OcH0UeHRlAb8HckqVm1AC7IPvfHw4OAPtUq7z3NFDwbq6i651Tu7f+i2bj31cX
 77Ames+fx6WjxUjyFbJwaK44E7Qez3waztdBfn91qw+m0b+gnKE3ieDNpJTqmm5b
 mKulV7KJwwS6cdqY3+Kr+pIlN+uuGAv7wGzVLcaEAXucDsVn/YAMJHY2+v97xv+n
 J9N+yeaYtmSXVlDsJ6dndMrTQMmcasK1CVXKxs+VYq5Lgf+A68w=
 =eoKm
 -----END PGP SIGNATURE-----

Merge tag 'x86_apic_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 apic updates from Dave Hansen:
 "This includes a very thorough rework of the 'struct apic' handlers.
  Quite a variety of them popped up over the years, especially in the
  32-bit days when odd apics were much more in vogue.

  The end result speaks for itself, which is a removal of a ton of code
  and static calls to replace indirect calls.

  If there's any breakage here, it's likely to be around the 32-bit
  museum pieces that get light to no testing these days.

  Summary:

   - Rework apic callbacks, getting rid of unnecessary ones and
     coalescing lots of silly duplicates.

   - Use static_calls() instead of indirect calls for apic->foo()

   - Tons of cleanups an crap removal along the way"

* tag 'x86_apic_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  x86/apic: Turn on static calls
  x86/apic: Provide static call infrastructure for APIC callbacks
  x86/apic: Wrap IPI calls into helper functions
  x86/apic: Mark all hotpath APIC callback wrappers __always_inline
  x86/xen/apic: Mark apic __ro_after_init
  x86/apic: Convert other overrides to apic_update_callback()
  x86/apic: Replace acpi_wake_cpu_handler_update() and apic_set_eoi_cb()
  x86/apic: Provide apic_update_callback()
  x86/xen/apic: Use standard apic driver mechanism for Xen PV
  x86/apic: Provide common init infrastructure
  x86/apic: Wrap apic->native_eoi() into a helper
  x86/apic: Nuke ack_APIC_irq()
  x86/apic: Remove pointless arguments from [native_]eoi_write()
  x86/apic/noop: Tidy up the code
  x86/apic: Remove pointless NULL initializations
  x86/apic: Sanitize APIC ID range validation
  x86/apic: Prepare x2APIC for using apic::max_apic_id
  x86/apic: Simplify X2APIC ID validation
  x86/apic: Add max_apic_id member
  x86/apic: Wrap APIC ID validation into an inline
  ...
2023-08-30 10:44:46 -07:00
Linus Torvalds
330235e874 ACPI updates for 6.6-rc1
- Update the ACPICA code in the kernel to upstream revision 20230628
    including the following changes:
    * Suppress a GCC 12 dangling-pointer warning (Philip Prindeville).
    * Reformat the ACPI_STATE_COMMON macro and its users (George Guo).
    * Replace the ternary operator with ACPI_MIN() (Jiangshan Yi).
    * Add support for _DSC as per ACPI 6.5 (Saket Dumbre).
    * Remove a duplicate macro from zephyr header (Najumon B.A).
    * Add data structures for GED and _EVT tracking (Jose Marinho).
    * Fix misspelled CDAT DSMAS define (Dave Jiang).
    * Simplify an error message in acpi_ds_result_push() (Christophe
      Jaillet).
    * Add a struct size macro related to SRAT (Dave Jiang).
    * Add AML_NO_OPERAND_RESOLVE flag to Timer (Abhishek Mainkar).
    * Add support for RISC-V external interrupt controllers in MADT (Sunil
      V L).
    * Add RHCT flags, CMO and MMU nodes (Sunil V L).
    * Change ACPICA version to 20230628 (Bob Moore).
 
  - Introduce new wrappers for ACPICA notify handler install/remove and
    convert multiple drivers to using their own Notify() handlers instead
    of the ACPI bus type .notify() slated for removal (Michal Wilczynski).
 
  - Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2 (Hans
    de Goede).
 
  - Put ACPI video and its child devices explicitly into D0 on boot to
    avoid platform firmware confusion (Kai-Heng Feng).
 
  - Add backlight=native DMI quirk for Lenovo Ideapad Z470 (Jiri Slaby).
 
  - Support obtaining physical CPU ID from MADT on LoongArch (Bibo Mao).
 
  - Convert ACPI CPU initialization to using _OSC instead of _PDC that
    has been depreceted since 2018 and dropped from the specification in
    ACPI 6.5 (Michal Wilczynski, Rafael Wysocki).
 
  - Drop non-functional nocrt parameter from ACPI thermal (Mario
    Limonciello).
 
  - Clean up the ACPI thermal driver, rework the handling of firmware
    notifications in it and make it provide a table of generic trip point
    structures to the core during initialization (Rafael Wysocki).
 
  - Defer enumeration of devices with _DEP pointing to IVSC (Wentong Wu).
 
  - Install SystemCMOS address space handler for ACPI000E (TAD) to meet
    platform firmware expectations on some platforms (Zhang Rui).
 
  - Fix finding the generic error data in the ACPi extlog driver for
    compatibility with old and new firmware interface versions (Xiaochun
    Lee).
 
  - Remove assorted unused declarations of functions (Yue Haibing).
 
  - Move AMBA bus scan handling into arm64 specific directory (Sudeep
    Holla).
 
  - Fix and clean up suspend-to-idle interface for AMD systems (Mario
    Limonciello, Andy Shevchenko).
 
  - Fix string truncation warning in pnpacpi_add_device() (Sunil V L).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAmTslAkSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxtvgQAIsYAHXgalMFCLTqxeRZ8IMMLh/oxVfp
 RDbZ7lsBNzhYKXNv0jczjDApvfOctplh+qVuRIyFPrVrD+xzPgI9eFaZx41B3UPy
 3UG/KphjtF+sAu8rSFM2qcL2P+NGWe1Okr2G8Mbvu6bkGjfHShX6HGR7YgIyrZVO
 VMVLWqLvjvvg/jkraozArTtlvMwTrpBFxgWQVPK9TLRwx+JfB7WV6Z1XkgbllpR5
 8Q+O9wyVWfAIrLk/HZJdYNkdwREi46d226ePs6tJkwzE8KCUna0U4WbVVPRjbSfI
 Mkpy7Bnn91EZdN43/3ZzPBNO6NJi7UsD46EwRMzf1v7KyfsttnKw/v/SMke6gKQW
 43gi0trdbVxEdnN33CmBb2k82YQ5tjVuNOwKNy4xvFZ4vTE+WTz2imXMdW28biLT
 sU1eYJXPzBUQ4Ja2x56a1DOp2C1uOcSHbTKNzmtFsmT2FIWOKN+9PrOjaFEn7cyU
 FwWSzcONLE/QC0cSr7cWYym06aY8INtAlCm0hrlpwBDyiVDACz/QZ3NQAmbXKr5z
 5JIDQ+8v6YvpIx48yDlTYaQPMEskkZ2udkmwZCh6Vs0fMGyo3DDWvAIltPmHuIoj
 KekfDK5pkJjftK67IlHioAkS3KGHy4VTybi4Sx8KjYy9Q4GPQ4TL2h18kInXGu4f
 tv7U9J6zx9mJ
 =aXc6
 -----END PGP SIGNATURE-----

Merge tag 'acpi-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:
 "These include new ACPICA material, a rework of the ACPI thermal
  driver, a switch-over of the ACPI processor driver to using _OSC
  instead of (long deprecated) _PDC for CPU initialization, a rework of
  firmware notifications handling in several drivers, fixes and cleanups
  for suspend-to-idle handling on AMD systems, ACPI backlight driver
  updates and more.

  Specifics:

   - Update the ACPICA code in the kernel to upstream revision 20230628
     including the following changes:
      - Suppress a GCC 12 dangling-pointer warning (Philip Prindeville)
      - Reformat the ACPI_STATE_COMMON macro and its users (George Guo)
      - Replace the ternary operator with ACPI_MIN() (Jiangshan Yi)
      - Add support for _DSC as per ACPI 6.5 (Saket Dumbre)
      - Remove a duplicate macro from zephyr header (Najumon B.A)
      - Add data structures for GED and _EVT tracking (Jose Marinho)
      - Fix misspelled CDAT DSMAS define (Dave Jiang)
      - Simplify an error message in acpi_ds_result_push() (Christophe
        Jaillet)
      - Add a struct size macro related to SRAT (Dave Jiang)
      - Add AML_NO_OPERAND_RESOLVE flag to Timer (Abhishek Mainkar)
      - Add support for RISC-V external interrupt controllers in MADT
        (Sunil V L)
      - Add RHCT flags, CMO and MMU nodes (Sunil V L)
      - Change ACPICA version to 20230628 (Bob Moore)

   - Introduce new wrappers for ACPICA notify handler install/remove and
     convert multiple drivers to using their own Notify() handlers
     instead of the ACPI bus type .notify() slated for removal (Michal
     Wilczynski)

   - Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2
     (Hans de Goede)

   - Put ACPI video and its child devices explicitly into D0 on boot to
     avoid platform firmware confusion (Kai-Heng Feng)

   - Add backlight=native DMI quirk for Lenovo Ideapad Z470 (Jiri Slaby)

   - Support obtaining physical CPU ID from MADT on LoongArch (Bibo Mao)

   - Convert ACPI CPU initialization to using _OSC instead of _PDC that
     has been depreceted since 2018 and dropped from the specification
     in ACPI 6.5 (Michal Wilczynski, Rafael Wysocki)

   - Drop non-functional nocrt parameter from ACPI thermal (Mario
     Limonciello)

   - Clean up the ACPI thermal driver, rework the handling of firmware
     notifications in it and make it provide a table of generic trip
     point structures to the core during initialization (Rafael Wysocki)

   - Defer enumeration of devices with _DEP pointing to IVSC (Wentong
     Wu)

   - Install SystemCMOS address space handler for ACPI000E (TAD) to meet
     platform firmware expectations on some platforms (Zhang Rui)

   - Fix finding the generic error data in the ACPi extlog driver for
     compatibility with old and new firmware interface versions
     (Xiaochun Lee)

   - Remove assorted unused declarations of functions (Yue Haibing)

   - Move AMBA bus scan handling into arm64 specific directory (Sudeep
     Holla)

   - Fix and clean up suspend-to-idle interface for AMD systems (Mario
     Limonciello, Andy Shevchenko)

   - Fix string truncation warning in pnpacpi_add_device() (Sunil V L)"

* tag 'acpi-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (66 commits)
  ACPI: x86: s2idle: Add a function to get LPS0 constraint for a device
  ACPI: x86: s2idle: Add for_each_lpi_constraint() helper
  ACPI: x86: s2idle: Add more debugging for AMD constraints parsing
  ACPI: x86: s2idle: Fix a logic error parsing AMD constraints table
  ACPI: x86: s2idle: Catch multiple ACPI_TYPE_PACKAGE objects
  ACPI: x86: s2idle: Post-increment variables when getting constraints
  ACPI: Adjust #ifdef for *_lps0_dev use
  ACPI: TAD: Install SystemCMOS address space handler for ACPI000E
  ACPI: Remove assorted unused declarations of functions
  ACPI: extlog: Fix finding the generic error data for v3 structure
  PNP: ACPI: Fix string truncation warning
  ACPI: Remove unused extern declaration acpi_paddr_to_node()
  ACPI: video: Add backlight=native DMI quirk for Apple iMac12,1 and iMac12,2
  ACPI: video: Put ACPI video and its child devices into D0 on boot
  ACPI: processor: LoongArch: Get physical ID from MADT
  ACPI: scan: Defer enumeration of devices with a _DEP pointing to IVSC device
  ACPI: thermal: Eliminate code duplication from acpi_thermal_notify()
  ACPI: thermal: Drop unnecessary thermal zone callbacks
  ACPI: thermal: Rework thermal_get_trend()
  ACPI: thermal: Use trip point table to register thermal zones
  ...
2023-08-28 17:58:39 -07:00
Linus Walleij
067e4f174f x86/xen: Make virt_to_pfn() a static inline
Making virt_to_pfn() a static inline taking a strongly typed
(const void *) makes the contract of a passing a pointer of that
type to the function explicit and exposes any misuse of the
macro virt_to_pfn() acting polymorphic and accepting many types
such as (void *), (unitptr_t) or (unsigned long) as arguments
without warnings.

Also fix all offending call sites to pass a (void *) rather
than an unsigned long. Since virt_to_mfn() is wrapping
virt_to_pfn() this function has become polymorphic as well
so the usage need to be fixed up.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20230810-virt-to-phys-x86-xen-v1-1-9e966d333e7a@linaro.org
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-08-21 09:52:29 +02:00
Juergen Gross
3b5244bef1 x86/xen/apic: Use standard apic driver mechanism for Xen PV
Instead of setting the Xen PV apic driver very early during boot, just use
the standard apic driver probing by setting an appropriate
x86_init.irqs.intr_mode_init callback.

At the same time eliminate xen_apic_check() which has never been used.

The #ifdef CONFIG_X86_LOCAL_APIC around the call of xen_init_apic()
can be removed, too, as CONFIG_XEN depends on CONFIG_X86_LOCAL_APIC.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)
Link: https://lore.kernel.org/lkml/aa086365-fd02-210f-67c6-5c9175c0dfee@suse.com
2023-08-09 12:00:41 -07:00
Rick Edgecombe
a5f6c2ace9 x86/shstk: Add user control-protection fault handler
A control-protection fault is triggered when a control-flow transfer
attempt violates Shadow Stack or Indirect Branch Tracking constraints.
For example, the return address for a RET instruction differs from the copy
on the shadow stack.

There already exists a control-protection fault handler for handling kernel
IBT faults. Refactor this fault handler into separate user and kernel
handlers, like the page fault handler. Add a control-protection handler
for usermode. To avoid ifdeffery, put them both in a new file cet.c, which
is compiled in the case of either of the two CET features supported in the
kernel: kernel IBT or user mode shadow stack. Move some static inline
functions from traps.c into a header so they can be used in cet.c.

Opportunistically fix a comment in the kernel IBT part of the fault
handler that is on the end of the line instead of preceding it.

Keep the same behavior for the kernel side of the fault handler, except for
converting a BUG to a WARN in the case of a #CP happening when the feature
is missing. This unifies the behavior with the new shadow stack code, and
also prevents the kernel from crashing under this situation which is
potentially recoverable.

The control-protection fault handler works in a similar way as the general
protection fault handler. It provides the si_code SEGV_CPERR to the signal
handler.

Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-28-rick.p.edgecombe%40intel.com
2023-08-02 15:01:50 -07:00
Michal Wilczynski
c9e6c5e64f ACPI: processor: Rename ACPI_PDC symbols
The prefix in the names of the ACPI_PDC symbols suggests that they are
only relevant for _PDC, but in fact they can also be used in the _OSC.

Change that prefix to a more generic ACPI_PROC_CAP that will better
reflect the purpose of those symbols as they represent bits in a general
processor capabilities buffer.

Rename pdc_intel.h to proc_cap_intel.h to follow the change of the
symbol name prefix.

No intentional functional impact.

Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-07-14 17:59:40 +02:00
Juergen Gross
30d65d1b19 x86/xen: Set default memory type for PV guests to WB
When running as an unprivileged PV guest under Xen (not dom0), the
default MTRR memory type should be write-back.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20230615123959.12298-1-jgross@suse.com
2023-06-16 11:22:33 +02:00
Juergen Gross
a153f254e5 x86/xen: Set MTRR state when running as Xen PV initial domain
When running as Xen PV initial domain (aka dom0), MTRRs are disabled
by the hypervisor, but the system should nevertheless use correct
cache memory types. This has always kind of worked, as disabled MTRRs
resulted in disabled PAT, too, so that the kernel avoided code paths
resulting in inconsistencies. This bypassed all of the sanity checks
the kernel is doing with enabled MTRRs in order to avoid memory
mappings with conflicting memory types.

This has been changed recently, leading to PAT being accepted to be
enabled, while MTRRs stayed disabled. The result is that
mtrr_type_lookup() no longer is accepting all memory type requests,
but started to return WB even if UC- was requested. This led to
driver failures during initialization of some devices.

In reality MTRRs are still in effect, but they are under complete
control of the Xen hypervisor. It is possible, however, to retrieve
the MTRR settings from the hypervisor.

In order to fix those problems, overwrite the MTRR state via
mtrr_overwrite_state() with the MTRR data from the hypervisor, if the
system is running as a Xen dom0.

Fixes: 72cbc8f04f ("x86/PAT: Have pat_enabled() properly reflect state when running on Xen")
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20230502120931.20719-6-jgross@suse.com
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2023-06-01 15:04:32 +02:00
Linus Torvalds
0eb392ec09 xen: branch for v6.3-rc3
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCZBQKJwAKCRCAXGG7T9hj
 vuVgAQDhvr5mBFNqFxIfTnE8+oEsnYb0OgmR+9U3h+ECDB0P0gEAmR1fAee441YE
 2DWOAlvjmqoI2K8DTTabizXvm7x3bQk=
 =jcYl
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-6.3-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - cleanup for xen time handling

 - enable the VGA console in a Xen PVH dom0

 - cleanup in the xenfs driver

* tag 'for-linus-6.3-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: remove unnecessary (void*) conversions
  x86/PVH: obtain VGA console info in Dom0
  x86/xen/time: cleanup xen_tsc_safe_clocksource
  xen: update arch/x86/include/asm/xen/cpuid.h
2023-03-17 10:45:49 -07:00
Jan Beulich
934ef33ee7 x86/PVH: obtain VGA console info in Dom0
A new platform-op was added to Xen to allow obtaining the same VGA
console information PV Dom0 is handed. Invoke the new function and have
the output data processed by xen_init_vga().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>

Link: https://lore.kernel.org/r/8f315e92-7bda-c124-71cc-478ab9c5e610@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2023-03-14 15:20:51 +01:00
Linus Torvalds
877934769e - Cache the AMD debug registers in per-CPU variables to avoid MSR writes
where possible, when supporting a debug registers swap feature for
   SEV-ES guests
 
 - Add support for AMD's version of eIBRS called Automatic IBRS which is
   a set-and-forget control of indirect branch restriction speculation
   resources on privilege change
 
 - Add support for a new x86 instruction - LKGS - Load kernel GS which is
   part of the FRED infrastructure
 
 - Reset SPEC_CTRL upon init to accomodate use cases like kexec which
   rediscover
 
 - Other smaller fixes and cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmP1RDIACgkQEsHwGGHe
 VUohBw//ZB9ZRqsrKdm6D9YaP2x4Zb+kqKqo6rjYeWaYqyPyCwDujPwh+pb3Oq1t
 aj62muDv1t/wEJc8mKNkfXkjEEtBVAOcpb5YIpKreoEvNKyevol83Ih0u5iJcTRE
 E5qf8HDS8b/JZrcazJJLl6WQmQNH5RiKSu5bbCpRhoeOcyo5pRYR5MztK9vNmAQk
 GMdwHsUSU+jN8uiE4HnpaOb/luhgFindRwZVTpdjJegQWLABS8cl3CKeTv4+PW45
 isvv37XnQP248wsptIEVRHeG6g3g/HtvwRx7DikUw06QwUyUK7H9hJssOoSP8TL9
 u4psRwfWnJ1OxU6klL+s0Ii+pjQ97wXmK/oqK7QkdUwhWqR/mQAW2e9kWHAngyDn
 A6mKbzSM6HFAeSXQpB9cMb6uvYRD44SngDFe3WXtEK8jiiQ70ikUm4E28I5KJOPg
 s+RyioHk0NFRHYSOOBqNG1NKz6ED7L3GbgbbzxkgMh21AAyI3X351t+PtGoLV5ew
 eqOsM7lbg9Scg1LvPk1JcoALS8USWqgar397rz9qGUs+OkPWBtEBCmTdMz/Eb+2t
 g/WHdLS5/ajSs5gNhT99W3DeqZMPDEkgBRSeyBBmY3CUD3gBL2wXEktRXv504zBR
 RC4oyUPX3c9E2ib6GATLE3kBLbcz9hTWbMxF+X3lLJvTVd/Qc2o=
 =v/ZC
 -----END PGP SIGNATURE-----

Merge tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpuid updates from Borislav Petkov:

 - Cache the AMD debug registers in per-CPU variables to avoid MSR
   writes where possible, when supporting a debug registers swap feature
   for SEV-ES guests

 - Add support for AMD's version of eIBRS called Automatic IBRS which is
   a set-and-forget control of indirect branch restriction speculation
   resources on privilege change

 - Add support for a new x86 instruction - LKGS - Load kernel GS which
   is part of the FRED infrastructure

 - Reset SPEC_CTRL upon init to accomodate use cases like kexec which
   rediscover

 - Other smaller fixes and cleanups

* tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/amd: Cache debug register values in percpu variables
  KVM: x86: Propagate the AMD Automatic IBRS feature to the guest
  x86/cpu: Support AMD Automatic IBRS
  x86/cpu, kvm: Add the SMM_CTL MSR not present feature
  x86/cpu, kvm: Add the Null Selector Clears Base feature
  x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf
  x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature
  KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code
  x86/cpu, kvm: Add support for CPUID_80000021_EAX
  x86/gsseg: Add the new <asm/gsseg.h> header to <asm/asm-prototypes.h>
  x86/gsseg: Use the LKGS instruction if available for load_gs_index()
  x86/gsseg: Move load_gs_index() to its own new header file
  x86/gsseg: Make asm_load_gs_index() take an u16
  x86/opcode: Add the LKGS instruction to x86-opcode-map
  x86/cpufeature: Add the CPU feature bit for LKGS
  x86/bugs: Reset speculation control settings on init
  x86/cpu: Remove redundant extern x86_read_arch_cap_msr()
2023-02-21 14:51:40 -08:00
Peter Zijlstra
10a099405f cpuidle, xenpv: Make more PARAVIRT_XXL noinstr clean
objtool found a few cases where this code called out into instrumented
code:

  vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section
  vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section
  vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section

Solve this by:

 - marking arch_safe_halt(), wbinvd(), native_wbinvd() and
   HYPERVISOR_sched_op() as __always_inline().

 - Explicitly uninlining xen_safe_halt() and pv_native_wbinvd() [they were
   already uninlined by the compiler on use as function pointers] and
   annotating them as 'noinstr'.

 - Annotating pv_native_safe_halt() as 'noinstr'.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195541.171918174@infradead.org
2023-01-13 11:48:16 +01:00
H. Peter Anvin (Intel)
92cbbadf73 x86/gsseg: Use the LKGS instruction if available for load_gs_index()
The LKGS instruction atomically loads a segment descriptor into the
%gs descriptor registers, *except* that %gs.base is unchanged, and the
base is instead loaded into MSR_IA32_KERNEL_GS_BASE, which is exactly
what we want this function to do.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230112072032.35626-6-xin3.li@intel.com
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
2023-01-13 10:07:27 +01:00
Linus Torvalds
94a855111e - Add the call depth tracking mitigation for Retbleed which has
been long in the making. It is a lighterweight software-only fix for
 Skylake-based cores where enabling IBRS is a big hammer and causes a
 significant performance impact.
 
 What it basically does is, it aligns all kernel functions to 16 bytes
 boundary and adds a 16-byte padding before the function, objtool
 collects all functions' locations and when the mitigation gets applied,
 it patches a call accounting thunk which is used to track the call depth
 of the stack at any time.
 
 When that call depth reaches a magical, microarchitecture-specific value
 for the Return Stack Buffer, the code stuffs that RSB and avoids its
 underflow which could otherwise lead to the Intel variant of Retbleed.
 
 This software-only solution brings a lot of the lost performance back,
 as benchmarks suggest:
 
   https://lore.kernel.org/all/20220915111039.092790446@infradead.org/
 
 That page above also contains a lot more detailed explanation of the
 whole mechanism
 
 - Implement a new control flow integrity scheme called FineIBT which is
 based on the software kCFI implementation and uses hardware IBT support
 where present to annotate and track indirect branches using a hash to
 validate them
 
 - Other misc fixes and cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmOZp5EACgkQEsHwGGHe
 VUrZFxAAvi/+8L0IYSK4mKJvixGbTFjxN/Swo2JVOfs34LqGUT6JaBc+VUMwZxdb
 VMTFIZ3ttkKEodjhxGI7oGev6V8UfhI37SmO2lYKXpQVjXXnMlv/M+Vw3teE38CN
 gopi+xtGnT1IeWQ3tc/Tv18pleJ0mh5HKWiW+9KoqgXj0wgF9x4eRYDz1TDCDA/A
 iaBzs56j8m/FSykZHnrWZ/MvjKNPdGlfJASUCPeTM2dcrXQGJ93+X2hJctzDte0y
 Nuiw6Y0htfFBE7xoJn+sqm5Okr+McoUM18/CCprbgSKYk18iMYm3ZtAi6FUQZS1A
 ua4wQCf49loGp15PO61AS5d3OBf5D3q/WihQRbCaJvTVgPp9sWYnWwtcVUuhMllh
 ZQtBU9REcVJ/22bH09Q9CjBW0VpKpXHveqQdqRDViLJ6v/iI6EFGmD24SW/VxyRd
 73k9MBGrL/dOf1SbEzdsnvcSB3LGzp0Om8o/KzJWOomrVKjBCJy16bwTEsCZEJmP
 i406m92GPXeaN1GhTko7vmF0GnkEdJs1GVCZPluCAxxbhHukyxHnrjlQjI4vC80n
 Ylc0B3Kvitw7LGJsPqu+/jfNHADC/zhx1qz/30wb5cFmFbN1aRdp3pm8JYUkn+l/
 zri2Y6+O89gvE/9/xUhMohzHsWUO7xITiBavewKeTP9GSWybWUs=
 =cRy1
 -----END PGP SIGNATURE-----

Merge tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 core updates from Borislav Petkov:

 - Add the call depth tracking mitigation for Retbleed which has been
   long in the making. It is a lighterweight software-only fix for
   Skylake-based cores where enabling IBRS is a big hammer and causes a
   significant performance impact.

   What it basically does is, it aligns all kernel functions to 16 bytes
   boundary and adds a 16-byte padding before the function, objtool
   collects all functions' locations and when the mitigation gets
   applied, it patches a call accounting thunk which is used to track
   the call depth of the stack at any time.

   When that call depth reaches a magical, microarchitecture-specific
   value for the Return Stack Buffer, the code stuffs that RSB and
   avoids its underflow which could otherwise lead to the Intel variant
   of Retbleed.

   This software-only solution brings a lot of the lost performance
   back, as benchmarks suggest:

       https://lore.kernel.org/all/20220915111039.092790446@infradead.org/

   That page above also contains a lot more detailed explanation of the
   whole mechanism

 - Implement a new control flow integrity scheme called FineIBT which is
   based on the software kCFI implementation and uses hardware IBT
   support where present to annotate and track indirect branches using a
   hash to validate them

 - Other misc fixes and cleanups

* tag 'x86_core_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (80 commits)
  x86/paravirt: Use common macro for creating simple asm paravirt functions
  x86/paravirt: Remove clobber bitmask from .parainstructions
  x86/debug: Include percpu.h in debugreg.h to get DECLARE_PER_CPU() et al
  x86/cpufeatures: Move X86_FEATURE_CALL_DEPTH from bit 18 to bit 19 of word 11, to leave space for WIP X86_FEATURE_SGX_EDECCSSA bit
  x86/Kconfig: Enable kernel IBT by default
  x86,pm: Force out-of-line memcpy()
  objtool: Fix weak hole vs prefix symbol
  objtool: Optimize elf_dirty_reloc_sym()
  x86/cfi: Add boot time hash randomization
  x86/cfi: Boot time selection of CFI scheme
  x86/ibt: Implement FineIBT
  objtool: Add --cfi to generate the .cfi_sites section
  x86: Add prefix symbols for function padding
  objtool: Add option to generate prefix symbols
  objtool: Avoid O(bloody terrible) behaviour -- an ode to libelf
  objtool: Slice up elf_create_section_symbol()
  kallsyms: Revert "Take callthunks into account"
  x86: Unconfuse CONFIG_ and X86_FEATURE_ namespaces
  x86/retpoline: Fix crash printing warning
  x86/paravirt: Fix a !PARAVIRT build warning
  ...
2022-12-14 15:03:00 -08:00
Linus Torvalds
4eb77fa102 - Do some spring cleaning to the compressed boot code by moving the
EFI mixed-mode code to a separate compilation unit, the AMD memory
 encryption early code where it belongs and fixing up build dependencies.
 Make the deprecated EFI handover protocol optional with the goal of
 removing it at some point (Ard Biesheuvel)
 
 - Skip realmode init code on Xen PV guests as it is not needed there
 
 - Remove an old 32-bit PIC code compiler workaround
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEzv7L6UO9uDPlPSfHEsHwGGHeVUoFAmOYaiMACgkQEsHwGGHe
 VUrNVhAAk3lLagEsrBcQ24SnMMAyQvdKfRucn9fbs72jBCyWbDqXcE59qNgdbMS1
 3rIL+EJdF8jlm5K28GjRS1WSvwUyYbyFEfUcYfqZl9L/5PAl7PlG7nNQw7/gXnw+
 xS57w/Q3cONlo5LC0K2Zkbj/59RvDoBEs3nkhozkKR0npTDW/LK3Vl0zgKTkvqsV
 DzRIHhWsqSEvpdowbQmQCyqFh/pOoQlZkQwjYVA9+SaQYdH3Yo1dpLd5i9I9eVmJ
 dci/HDU+plwYYuZ1XhxwXr82PcdCUVYjJ/DTt9GkTVYq7u5EWx62puxTl+c+wbG2
 H1WBXuZHBGdzNMFdnb1k9RuLCaYdaxKTNlZh3FPMMDtkjtjKTl/olXTlFUYFgI6E
 FPv4hi15g6pMveS3K6YUAd0uGvpsjvLUZHPqMDVS2trhxLENQALc6Id/PwqzrQ1T
 FzfPYcDyFFwMM3MDuWc8ClwEDD9wr0Z4m4Aek/ca2r85AKEX8ZtTTlWZoI4E9A4B
 hEjUFnRhT/d6XLWwZqcOIKfwtbpKAjdsCN3ElFst8ogRFAXqW8luDoI4BRCkBC4p
 T4RHdij4afkuFjSAxBacazpaavtcCsDqXwBpeL4YN+4fA7+NokVZGiQVh/3S8BPn
 LlgIf6awFq6yQq7JyEGPdk+dWn5sknldixZ55m666ZLzSvQhvE8=
 =VGZx
 -----END PGP SIGNATURE-----

Merge tag 'x86_boot_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 boot updates from Borislav Petkov:
 "A  of early boot cleanups and fixes.

   - Do some spring cleaning to the compressed boot code by moving the
     EFI mixed-mode code to a separate compilation unit, the AMD memory
     encryption early code where it belongs and fixing up build
     dependencies. Make the deprecated EFI handover protocol optional
     with the goal of removing it at some point (Ard Biesheuvel)

   - Skip realmode init code on Xen PV guests as it is not needed there

   - Remove an old 32-bit PIC code compiler workaround"

* tag 'x86_boot_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Remove x86_32 PIC using %ebx workaround
  x86/boot: Skip realmode init code when running as Xen PV guest
  x86/efi: Make the deprecated EFI handover protocol optional
  x86/boot/compressed: Only build mem_encrypt.S if AMD_MEM_ENCRYPT=y
  x86/boot/compressed: Adhere to calling convention in get_sev_encryption_bit()
  x86/boot/compressed: Move startup32_check_sev_cbit() out of head_64.S
  x86/boot/compressed: Move startup32_check_sev_cbit() into .text
  x86/boot/compressed: Move startup32_load_idt() out of head_64.S
  x86/boot/compressed: Move startup32_load_idt() into .text section
  x86/boot/compressed: Pull global variable reference into startup32_load_idt()
  x86/boot/compressed: Avoid touching ECX in startup32_set_idt_entry()
  x86/boot/compressed: Simplify IDT/GDT preserve/restore in the EFI thunk
  x86/boot/compressed, efi: Merge multiple definitions of image_offset into one
  x86/boot/compressed: Move efi32_pe_entry() out of head_64.S
  x86/boot/compressed: Move efi32_entry out of head_64.S
  x86/boot/compressed: Move efi32_pe_entry into .text section
  x86/boot/compressed: Move bootargs parsing out of 32-bit startup code
  x86/boot/compressed: Move 32-bit entrypoint code into .text section
  x86/boot/compressed: Rename efi_thunk_64.S to efi-mixed.S
2022-12-13 14:45:29 -08:00
Linus Torvalds
268325bda5 Random number generator updates for Linux 6.2-rc1.
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEEq5lC5tSkz8NBJiCnSfxwEqXeA64FAmOU+U8ACgkQSfxwEqXe
 A67NnQ//Y5DltmvibyPd7r1TFT2gUYv+Rx3sUV9ZE1NYptd/SWhhcL8c5FZ70Fuw
 bSKCa1uiWjOxosjXT1kGrWq3de7q7oUpAPSOGxgxzoaNURIt58N/ajItCX/4Au8I
 RlGAScHy5e5t41/26a498kB6qJ441fBEqCYKQpPLINMBAhe8TQ+NVp0rlpUwNHFX
 WrUGg4oKWxdBIW3HkDirQjJWDkkAiklRTifQh/Al4b6QDbOnRUGGCeckNOhixsvS
 waHWTld+Td8jRrA4b82tUb2uVZ2/b8dEvj/A8CuTv4yC0lywoyMgBWmJAGOC+UmT
 ZVNdGW02Jc2T+Iap8ZdsEmeLHNqbli4+IcbY5xNlov+tHJ2oz41H9TZoYKbudlr6
 /ReAUPSn7i50PhbQlEruj3eg+M2gjOeh8OF8UKwwRK8PghvyWQ1ScW0l3kUhPIhI
 PdIG6j4+D2mJc1FIj2rTVB+Bg933x6S+qx4zDxGlNp62AARUFYf6EgyD6aXFQVuX
 RxcKb6cjRuFkzFiKc8zkqg5edZH+IJcPNuIBmABqTGBOxbZWURXzIQvK/iULqZa4
 CdGAFIs6FuOh8pFHLI3R4YoHBopbHup/xKDEeAO9KZGyeVIuOSERDxxo5f/ITzcq
 APvT77DFOEuyvanr8RMqqh0yUjzcddXqw9+ieufsAyDwjD9DTuE=
 =QRhK
 -----END PGP SIGNATURE-----

Merge tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random

Pull random number generator updates from Jason Donenfeld:

 - Replace prandom_u32_max() and various open-coded variants of it,
   there is now a new family of functions that uses fast rejection
   sampling to choose properly uniformly random numbers within an
   interval:

       get_random_u32_below(ceil) - [0, ceil)
       get_random_u32_above(floor) - (floor, U32_MAX]
       get_random_u32_inclusive(floor, ceil) - [floor, ceil]

   Coccinelle was used to convert all current users of
   prandom_u32_max(), as well as many open-coded patterns, resulting in
   improvements throughout the tree.

   I'll have a "late" 6.1-rc1 pull for you that removes the now unused
   prandom_u32_max() function, just in case any other trees add a new
   use case of it that needs to converted. According to linux-next,
   there may be two trivial cases of prandom_u32_max() reintroductions
   that are fixable with a 's/.../.../'. So I'll have for you a final
   conversion patch doing that alongside the removal patch during the
   second week.

   This is a treewide change that touches many files throughout.

 - More consistent use of get_random_canary().

 - Updates to comments, documentation, tests, headers, and
   simplification in configuration.

 - The arch_get_random*_early() abstraction was only used by arm64 and
   wasn't entirely useful, so this has been replaced by code that works
   in all relevant contexts.

 - The kernel will use and manage random seeds in non-volatile EFI
   variables, refreshing a variable with a fresh seed when the RNG is
   initialized. The RNG GUID namespace is then hidden from efivarfs to
   prevent accidental leakage.

   These changes are split into random.c infrastructure code used in the
   EFI subsystem, in this pull request, and related support inside of
   EFISTUB, in Ard's EFI tree. These are co-dependent for full
   functionality, but the order of merging doesn't matter.

 - Part of the infrastructure added for the EFI support is also used for
   an improvement to the way vsprintf initializes its siphash key,
   replacing an sleep loop wart.

 - The hardware RNG framework now always calls its correct random.c
   input function, add_hwgenerator_randomness(), rather than sometimes
   going through helpers better suited for other cases.

 - The add_latent_entropy() function has long been called from the fork
   handler, but is a no-op when the latent entropy gcc plugin isn't
   used, which is fine for the purposes of latent entropy.

   But it was missing out on the cycle counter that was also being mixed
   in beside the latent entropy variable. So now, if the latent entropy
   gcc plugin isn't enabled, add_latent_entropy() will expand to a call
   to add_device_randomness(NULL, 0), which adds a cycle counter,
   without the absent latent entropy variable.

 - The RNG is now reseeded from a delayed worker, rather than on demand
   when used. Always running from a worker allows it to make use of the
   CPU RNG on platforms like S390x, whose instructions are too slow to
   do so from interrupts. It also has the effect of adding in new inputs
   more frequently with more regularity, amounting to a long term
   transcript of random values. Plus, it helps a bit with the upcoming
   vDSO implementation (which isn't yet ready for 6.2).

 - The jitter entropy algorithm now tries to execute on many different
   CPUs, round-robining, in hopes of hitting even more memory latencies
   and other unpredictable effects. It also will mix in a cycle counter
   when the entropy timer fires, in addition to being mixed in from the
   main loop, to account more explicitly for fluctuations in that timer
   firing. And the state it touches is now kept within the same cache
   line, so that it's assured that the different execution contexts will
   cause latencies.

* tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (23 commits)
  random: include <linux/once.h> in the right header
  random: align entropy_timer_state to cache line
  random: mix in cycle counter when jitter timer fires
  random: spread out jitter callback to different CPUs
  random: remove extraneous period and add a missing one in comments
  efi: random: refresh non-volatile random seed when RNG is initialized
  vsprintf: initialize siphash key using notifier
  random: add back async readiness notifier
  random: reseed in delayed work rather than on-demand
  random: always mix cycle counter in add_latent_entropy()
  hw_random: use add_hwgenerator_randomness() for early entropy
  random: modernize documentation comment on get_random_bytes()
  random: adjust comment to account for removed function
  random: remove early archrandom abstraction
  random: use random.trust_{bootloader,cpu} command line option only
  stackprotector: actually use get_random_canary()
  stackprotector: move get_random_canary() into stackprotector.h
  treewide: use get_random_u32_inclusive() when possible
  treewide: use get_random_u32_{above,below}() instead of manual loop
  treewide: use get_random_u32_below() instead of deprecated function
  ...
2022-12-12 16:22:22 -08:00
Juergen Gross
f1e5250094 x86/boot: Skip realmode init code when running as Xen PV guest
When running as a Xen PV guest there is no need for setting up the
realmode trampoline, as realmode isn't supported in this environment.

Trying to setup the trampoline has been proven to be problematic in
some cases, especially when trying to debug early boot problems with
Xen requiring to keep the EFI boot-services memory mapped (some
firmware variants seem to claim basically all memory below 1Mb for boot
services).

Introduce new x86_platform_ops operations for that purpose, which can
be set to a NOP by the Xen PV specific kernel boot code.

  [ bp: s/call_init_real_mode/do_init_real_mode/ ]

Fixes: 084ee1c641 ("x86, realmode: Relocator for realmode code")
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20221123114523.3467-1-jgross@suse.com
2022-11-25 12:05:22 +01:00
Ingo Molnar
0ce096db71 Linux 6.1-rc6
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmN6wAgeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG0EYH/3/RO90NbrFItraN
 Lzr+d3VdbGjTu8xd1M+PRTmwh3zxLpB+Jwqr0T0A2gzL9B/D+AUPUJdrCVbv9DqS
 FLJAVqoeV20dNBAHSffOOLPsgCZ+Eu+LzlNN7Iqde0e8cyZICFMNktitui84Xm/i
 1NgFVgz9OZ6+aieYvUj3FrFq0p8GTIaC/oybDZrxYKcO8ZzKVMJ11swRw10wwq0g
 qOOECvV3w7wlQ8upQZkzFxItKFc7EexZI6R4elXeGSJJ9Hlc092dv/zsKB9dwV+k
 WcwkJrZRoezYXzgGBFxUcQtzi+ethjrPjuJuM1rYLUSIcfIW/0lkaSLgRoBu8D+I
 1GfXkXs=
 =gt6P
 -----END PGP SIGNATURE-----

Merge tag 'v6.1-rc6' into x86/core, to resolve conflicts

Resolve conflicts between these commits in arch/x86/kernel/asm-offsets.c:

 # upstream:
 debc5a1ec0 ("KVM: x86: use a separate asm-offsets.c file")

 # retbleed work in x86/core:
 5d8213864a ("x86/retbleed: Add SKL return thunk")

... and these commits in include/linux/bpf.h:

  # upstram:
  18acb7fac2 ("bpf: Revert ("Fix dispatcher patchable function entry to 5 bytes nop")")

  # x86/core commits:
  931ab63664 ("x86/ibt: Implement FineIBT")
  bea75b3389 ("x86/Kconfig: Introduce function padding")

The latter two modify BPF_DISPATCHER_ATTRIBUTES(), which was removed upstream.

 Conflicts:
	arch/x86/kernel/asm-offsets.c
	include/linux/bpf.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2022-11-21 23:01:51 +01:00
Jason A. Donenfeld
b3883a9a1f stackprotector: move get_random_canary() into stackprotector.h
This has nothing to do with random.c and everything to do with stack
protectors. Yes, it uses randomness. But many things use randomness.
random.h and random.c are concerned with the generation of randomness,
not with each and every use. So move this function into the more
specific stackprotector.h file where it belongs.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-11-18 02:18:10 +01:00
Linus Torvalds
cc675d22e4 xen: branch for v6.1-rc6
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCY3TN0wAKCRCAXGG7T9hj
 voAOAP4i3FjRj/ilXohox3F7iyPsRbFrGnayYcHRPeFF8UPz8QEAzyLP/FBGbmho
 sSuhcmb6r9foGKri7zyTKHIA4bkz4Qo=
 =/KaG
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-6.1-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "Two trivial cleanups, and three simple fixes"

* tag 'for-linus-6.1-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/platform-pci: use define instead of literal number
  xen/platform-pci: add missing free_irq() in error path
  xen-pciback: Allow setting PCI_MSIX_FLAGS_MASKALL too
  xen/pcpu: fix possible memory leak in register_pcpu()
  x86/xen: Use kstrtobool() instead of strtobool()
2022-11-16 10:49:06 -08:00
Christophe JAILLET
639b2e2ff1 x86/xen: Use kstrtobool() instead of strtobool()
strtobool() is the same as kstrtobool().
However, the latter is more used within the kernel.

In order to remove strtobool() and slightly simplify kstrtox.h, switch to
the other function name.

While at it, include the corresponding header file (<linux/kstrtox.h>)

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/e91af3c8708af38b1c57e0a2d7eb9765dda0e963.1667336095.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-11-14 13:29:01 +01:00
Thomas Gleixner
1f19e2d50b x86/cpu: Get rid of redundant switch_to_new_gdt() invocations
The only place where switch_to_new_gdt() is required is early boot to
switch from the early GDT to the direct GDT. Any other invocation is
completely redundant because it does not change anything.

Secondary CPUs come out of the ASM code with GDT and GSBASE correctly set
up. The same is true for XEN_PV.

Remove all the voodoo invocations which are left overs from the ancient
past, rename the function to switch_gdt_and_percpu_base() and mark it init.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111143.198076128@infradead.org
2022-10-17 16:40:56 +02:00
Linus Torvalds
778ce723e9 xen: branch for v6.1-rc1
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQRTLbB6QfY48x44uB6AXGG7T9hjvgUCY0ZjFAAKCRCAXGG7T9hj
 vjEsAP4rFMnqc6AXy4Mpvv8cxBtEuQZbwEqgBrMJUvK1jZQrBQD/dOJK2GBCVcfD
 2yaVlefFiJGTw5WUlbPeohUlTZ8pJwg=
 =xsHV
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-6.1-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - Some minor typo fixes

 - A fix of the Xen pcifront driver for supporting the device model to
   run in a Linux stub domain

 - A cleanup of the pcifront driver

 - A series to enable grant-based virtio with Xen on x86

 - A cleanup of Xen PV guests to distinguish between safe and faulting
   MSR accesses

 - Two fixes of the Xen gntdev driver

 - Two fixes of the new xen grant DMA driver

* tag 'for-linus-6.1-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Kconfig: Fix spelling mistake "Maxmium" -> "Maximum"
  xen/pv: support selecting safe/unsafe msr accesses
  xen/pv: refactor msr access functions to support safe and unsafe accesses
  xen/pv: fix vendor checks for pmu emulation
  xen/pv: add fault recovery control to pmu msr accesses
  xen/virtio: enable grant based virtio on x86
  xen/virtio: use dom0 as default backend for CONFIG_XEN_VIRTIO_FORCE_GRANT
  xen/virtio: restructure xen grant dma setup
  xen/pcifront: move xenstore config scanning into sub-function
  xen/gntdev: Accommodate VMA splitting
  xen/gntdev: Prevent leaking grants
  xen/virtio: Fix potential deadlock when accessing xen_grant_dma_devices
  xen/virtio: Fix n_pages calculation in xen_grant_dma_map(unmap)_page()
  xen/xenbus: Fix spelling mistake "hardward" -> "hardware"
  xen-pcifront: Handle missed Connected state
2022-10-12 14:39:38 -07:00
Juergen Gross
3fac3734c4 xen/pv: support selecting safe/unsafe msr accesses
Instead of always doing the safe variants for reading and writing MSRs
in Xen PV guests, make the behavior controllable via Kconfig option
and a boot parameter.

The default will be the current behavior, which is to always use the
safe variant.

Signed-off-by: Juergen Gross <jgross@suse.com>
2022-10-11 10:51:05 +02:00
Juergen Gross
a1886b915e xen/pv: refactor msr access functions to support safe and unsafe accesses
Refactor and rename xen_read_msr_safe() and xen_write_msr_safe() to
support both cases of MSR accesses, safe ones and potentially GP-fault
generating ones.

This will prepare to no longer swallow GPs silently in xen_read_msr()
and xen_write_msr().

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-10-11 10:50:58 +02:00
Juergen Gross
61367688f1 xen/virtio: enable grant based virtio on x86
Use an x86-specific virtio_check_mem_acc_cb() for Xen in order to setup
the correct DMA ops.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # common code
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-10-10 14:31:26 +02:00
Kees Cook
3e1730842f x86/entry: Work around Clang __bdos() bug
Clang produces a false positive when building with CONFIG_FORTIFY_SOURCE=y
and CONFIG_UBSAN_BOUNDS=y when operating on an array with a dynamic
offset. Work around this by using a direct assignment of an empty
instance. Avoids this warning:

../include/linux/fortify-string.h:309:4: warning: call to __write_overflow_field declared with 'warn
ing' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wat
tribute-warning]
                        __write_overflow_field(p_size_field, size);
                        ^

which was isolated to the memset() call in xen_load_idt().

Note that this looks very much like another bug that was worked around:
https://github.com/ClangBuiltLinux/linux/issues/1592

Cc: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: xen-devel@lists.xenproject.org
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/lkml/41527d69-e8ab-3f86-ff37-6b298c01d5bc@oracle.com
Signed-off-by: Kees Cook <keescook@chromium.org>
2022-09-26 11:01:32 -07:00
Juergen Gross
251e90e7e3 xen: don't require virtio with grants for non-PV guests
Commit fa1f57421e ("xen/virtio: Enable restricted memory access using
Xen grant mappings") introduced a new requirement for using virtio
devices: the backend now needs to support the VIRTIO_F_ACCESS_PLATFORM
feature.

This is an undue requirement for non-PV guests, as those can be operated
with existing backends without any problem, as long as those backends
are running in dom0.

Per default allow virtio devices without grant support for non-PV
guests.

On Arm require VIRTIO_F_ACCESS_PLATFORM for devices having been listed
in the device tree to use grants.

Add a new config item to always force use of grants for virtio.

Fixes: fa1f57421e ("xen/virtio: Enable restricted memory access using Xen grant mappings")
Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 guest using Xen
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/20220622063838.8854-4-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-08-01 07:43:03 +02:00
Juergen Gross
96e8fc5818 x86/xen: Use clear_bss() for Xen PV guests
Instead of clearing the bss area in assembly code, use the clear_bss()
function.

This requires to pass the start_info address as parameter to
xen_start_kernel() in order to avoid the xen_start_info being zeroed
again.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20220630071441.28576-2-jgross@suse.com
2022-07-01 10:57:52 +02:00
Juergen Gross
fa1f57421e xen/virtio: Enable restricted memory access using Xen grant mappings
In order to support virtio in Xen guests add a config option XEN_VIRTIO
enabling the user to specify whether in all Xen guests virtio should
be able to access memory via Xen grant mappings only on the host side.

Also set PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS feature from the guest
initialization code on Arm and x86 if CONFIG_XEN_VIRTIO is enabled.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/1654197833-25362-5-git-send-email-olekstysh@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-06 16:07:30 +02:00
Rafael J. Wysocki
14c03a4a75 Merge back reboot/poweroff notifiers rework for 5.19-rc1. 2022-05-25 14:38:29 +02:00
Dmitry Osipenko
f089ab674c xen/x86: Use do_kernel_power_off()
Kernel now supports chained power-off handlers. Use do_kernel_power_off()
that invokes chained power-off handlers. It also invokes legacy
pm_power_off() for now, which will be removed once all drivers will
be converted to the new sys-off API.

Acked-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-05-19 19:30:30 +02:00
Maximilian Heyne
1591a65f55 x86: xen: remove STACK_FRAME_NON_STANDARD from xen_cpuid
Since commit 4d65adfcd1 ("x86: xen: insn: Decode Xen and KVM
emulate-prefix signature"), objtool is able to correctly parse the
prefixed instruction in xen_cpuid and emit correct orc unwind
information. Hence, marking the function as STACKFRAME_NON_STANDARD is
no longer needed.

This commit is basically a revert of commit 983bb6d254 ("x86/xen: Mark
xen_cpuid() stack frame as non-standard").

Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
CC: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/20220517162425.100567-1-mheyne@amazon.de
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-05-19 14:39:50 +02:00
Peter Zijlstra
5b2fc51576 x86/ibt,xen: Sprinkle the ENDBR
Even though Xen currently doesn't advertise IBT, prepare for when it
will eventually do so and sprinkle the ENDBR dust accordingly.

Even though most of the entry points are IRET like, the CPL0
Hypervisor can set WAIT-FOR-ENDBR and demand ENDBR at these sites.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.873919996@infradead.org
2022-03-15 10:32:35 +01:00
Peter Zijlstra
8b87d8cec1 x86/entry,xen: Early rewrite of restore_regs_and_return_to_kernel()
By doing an early rewrite of 'jmp native_iret` in
restore_regs_and_return_to_kernel() we can get rid of the last
INTERRUPT_RETURN user and paravirt_iret.

Suggested-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.815039833@infradead.org
2022-03-15 10:32:34 +01:00
Jan Beulich
e25a8d9599 x86/Xen: streamline (and fix) PV CPU enumeration
This started out with me noticing that "dom0_max_vcpus=<N>" with <N>
larger than the number of physical CPUs reported through ACPI tables
would not bring up the "excess" vCPU-s. Addressing this is the primary
purpose of the change; CPU maps handling is being tidied only as far as
is necessary for the change here (with the effect of also avoiding the
setting up of too much per-CPU infrastructure, i.e. for CPUs which can
never come online).

Noticing that xen_fill_possible_map() is called way too early, whereas
xen_filter_cpu_maps() is called too late (after per-CPU areas were
already set up), and further observing that each of the functions serves
only one of Dom0 or DomU, it looked like it was better to simplify this.
Use the .get_smp_config hook instead, uniformly for Dom0 and DomU.
xen_fill_possible_map() can be dropped altogether, while
xen_filter_cpu_maps() is re-purposed but not otherwise changed.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/2dbd5f0a-9859-ca2d-085e-a02f7166c610@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-02-03 08:25:04 +01:00
Juergen Gross
3ac876e8b5 xen: remove highmem remnants
There are some references to highmem left in Xen pv specific code which
can be removed.

Signed-off-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20211028081221.2475-4-jgross@suse.com
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02 08:11:02 -05:00
Juergen Gross
12ad6cfc09 x86/xen: remove xen_have_vcpu_info_placement flag
The flag xen_have_vcpu_info_placement was needed to support Xen
hypervisors older than version 3.4, which didn't support the
VCPUOP_register_vcpu_info hypercall. Today the Linux kernel requires
at least Xen 4.0 to be able to run, so xen_have_vcpu_info_placement
can be dropped (in theory the flag was used to ensure a working kernel
even in case of the VCPUOP_register_vcpu_info hypercall failing for
other reasons than the hypercall not being supported, but the only
cases covered by the flag would be parameter errors, which ought not
to be made anyway).

This allows to let some functions return void now, as they can never
fail.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20211028072748.29862-2-jgross@suse.com
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2021-11-02 07:45:44 -05:00
Linus Torvalds
43aa0a195f objtool updates:
- Improve retpoline code patching by separating it from alternatives which
    reduces memory footprint and allows to do better optimizations in the
    actual runtime patching.
 
  - Add proper retpoline support for x86/BPF
 
  - Address noinstr warnings in x86/kvm, lockdep and paravirtualization code
 
  - Add support to handle pv_opsindirect calls in the noinstr analysis
 
  - Classify symbols upfront and cache the result to avoid redundant
    str*cmp() invocations.
 
  - Add a CFI hash to reduce memory consumption which also reduces runtime
    on a allyesconfig by ~50%
 
  - Adjust XEN code to make objtool handling more robust and as a side
    effect to prevent text fragmentation due to placement of the hypercall
    page.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmF/GFgTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoc1JD/0Sz6seP2OUMxbMT3gCcFo9sMvYTdsM
 7WuGFbBbnCIo7g8JH7k0zRRBigptMp2eUtQXKkgaaIbWN4JbuVKf8KxN5/qXxLi4
 fJ12QnNTGH9N2jtzl5wKmpjaKJnnJMD9D10XwoR+T6gn6NHd+AgLEs7GxxuQUlgo
 eC9oEXhNHC8uNhiZc38EwfwmItI1bRgaLrnZWIL4rYGSMxfCK1/cEOpWrFfX9wmj
 /diB6oqMyPXZXMCtgpX7TniUr5XOTCcUkeO9mQv5bmyq/YM/8hrTbcVSJlsVYLvP
 EsBnUSHAcfLFiHXwa1RNiIGdbiPjbN+UYeXGAvqF58f3e5dTIHtN/UmWo7OH93If
 9rLMVNcMpsfPx7QRk2IxEPumLCkyfwjzfKrVDM6P6TKEIUzD1og4IK9gTlfykVsh
 56G5XiCOC/X2x8IMxKTLGuBiAVLFHXK/rSwoqhvNEWBFKDbP13QWs0LurBcW09Sa
 /kQI9pIBT1xFA/R+OY5Xy1cqNVVK1Gxmk8/bllCijA9pCFSCFM4hLZE5CevdrBCV
 h5SdqEK5hIlzFyypXfsCik/4p/+rfvlGfUKtFsPctxx29SPe+T0orx+l61jiWQok
 rZOflwMawK5lDuASHrvNHGJcWaTwoo3VcXMQDnQY0Wulc43J5IFBaPxkZzgyd+S1
 4lktHxatrCMUgw==
 =pfZi
 -----END PGP SIGNATURE-----

Merge tag 'objtool-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Thomas Gleixner:

 - Improve retpoline code patching by separating it from alternatives
   which reduces memory footprint and allows to do better optimizations
   in the actual runtime patching.

 - Add proper retpoline support for x86/BPF

 - Address noinstr warnings in x86/kvm, lockdep and paravirtualization
   code

 - Add support to handle pv_opsindirect calls in the noinstr analysis

 - Classify symbols upfront and cache the result to avoid redundant
   str*cmp() invocations.

 - Add a CFI hash to reduce memory consumption which also reduces
   runtime on a allyesconfig by ~50%

 - Adjust XEN code to make objtool handling more robust and as a side
   effect to prevent text fragmentation due to placement of the
   hypercall page.

* tag 'objtool-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  bpf,x86: Respect X86_FEATURE_RETPOLINE*
  bpf,x86: Simplify computing label offsets
  x86,bugs: Unconditionally allow spectre_v2=retpoline,amd
  x86/alternative: Add debug prints to apply_retpolines()
  x86/alternative: Try inline spectre_v2=retpoline,amd
  x86/alternative: Handle Jcc __x86_indirect_thunk_\reg
  x86/alternative: Implement .retpoline_sites support
  x86/retpoline: Create a retpoline thunk array
  x86/retpoline: Move the retpoline thunk declarations to nospec-branch.h
  x86/asm: Fixup odd GEN-for-each-reg.h usage
  x86/asm: Fix register order
  x86/retpoline: Remove unused replacement symbols
  objtool,x86: Replace alternatives with .retpoline_sites
  objtool: Shrink struct instruction
  objtool: Explicitly avoid self modifying code in .altinstr_replacement
  objtool: Classify symbols
  objtool: Support pv_opsindirect calls for noinstr
  x86/xen: Rework the xen_{cpu,irq,mmu}_opsarrays
  x86/xen: Mark xen_force_evtchn_callback() noinstr
  x86/xen: Make irq_disable() noinstr
  ...
2021-11-01 13:24:43 -07:00
Peter Zijlstra
b08cadbd3b Merge branch 'objtool/urgent'
Fixup conflicts.

# Conflicts:
#	tools/objtool/check.c
2021-10-07 00:40:17 +02:00
Jan Beulich
079c4baa2a xen/x86: hook up xen_banner() also for PVH
This was effectively lost while dropping PVHv1 code. Move the function
and arrange for it to be called the same way as done in PV mode. Clearly
this then needs re-introducing the XENFEAT_mmu_pt_update_preserve_ad
check that was recently removed, as that's a PV-only feature.

Since the string pointed at by pv_info.name describes the mode, drop
"paravirtualized" from the log message while moving the code.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/de03054d-a20d-2114-bb86-eec28e17b3b8@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2021-10-05 08:36:14 +02:00
Jan Beulich
4d1ab432ac xen/x86: generalize preferred console model from PV to PVH Dom0
Without announcing hvc0 as preferred it won't get used as long as tty0
gets registered earlier. This is particularly problematic with there not
being any screen output for PVH Dom0 when the screen is in graphics
mode, as the necessary information doesn't get conveyed yet from the
hypervisor.

Follow PV's model, but be conservative and do this for Dom0 only for
now.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/582328b6-c86c-37f3-d802-5539b7a86736@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2021-10-05 08:36:12 +02:00