Merge branch 'next' into for-linus

Prepare input updates for 6.12 merge window.

Merge tag 'v6.10' into next

Sync up with mainline to bring in device_for_each_child_node_scoped()
and other newer APIs.

Merge drm-misc-next-2024-07-04 into drm-misc-next-fixes

Let's start the drm-misc-next-fixes cycle.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge drm/drm-next into drm-intel-next

Sync to v6.10-rc3.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Merge drm/drm-next into drm-xe-next

Needed to get tracing cleanup and add mmio tracing series.

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Merge remote-tracking branch 'drm-misc/drm-misc-next' into HEAD

Merge drm-misc-next tree into the msm-next tree in order to be able to
use HDMI connector framework for the MSM HDMI driver.

Merge drm/drm-next into drm-misc-next

Let's start the new release cycle.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge branch 'tip/x86/cpu'

The Lunarlake patches rely on the new VFM stuff.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>

Merge topic branches 'clkdev' and 'fixes' into for-linus

Merge remote-tracking branch 'drm/drm-fixes' into drm-misc-fixes

v6.10-rc1 is released, forward from v6.9

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Cross merge.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Merge tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Alexander Gordeev:

- Store AP Query Configuration Information in a static buffer

- Rewo

Merge tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Alexander Gordeev:

- Store AP Query Configuration Information in a static buffer

- Rework the AP initialization and add missing cleanups to the error
path

- Swap IRQ and AP bus/device registration to avoid race conditions

- Export prot_virt_guest symbol

- Introduce AP configuration changes notifier interface to facilitate
modularization of the AP bus

- Add CONFIG_AP kernel configuration option to allow modularization of
the AP bus

- Rework CONFIG_ZCRYPT_DEBUG kernel configuration option description
and dependency and rename it to CONFIG_AP_DEBUG

- Convert sprintf() and snprintf() to sysfs_emit() in CIO code

- Adjust indentation of RELOCS command build step

- Make crypto performance counters upward compatible

- Convert make_page_secure() and gmap_make_secure() to use folio

- Rework channel-utilization-block (CUB) handling in preparation of
introducing additional CUBs

- Use attribute groups to simplify registration, removal and extension
of measurement-related channel-path sysfs attributes

- Add a per-channel-path binary "ext_measurement" sysfs attribute that
provides access to extended channel-path measurement data

- Export measurement data for all channel-measurement-groups (CMG), not
only for a specific ones. This enables support of new CMG data
formats in userspace without the need for kernel changes

- Add a per-channel-path sysfs attribute "speed_bps" that provides the
operating speed in bits per second or 0 if the operating speed is not
available

- The CIO tracepoint subchannel-type field "st" is incorrectly set to
the value of subchannel-enabled SCHIB "ena" field. Fix that

- Do not forcefully limit vmemmap starting address to MAX_PHYSMEM_BITS

- Consider the maximum physical address available to a DCSS segment
(512GB) when memory layout is set up

- Simplify the virtual memory layout setup by reducing the size of
identity mapping vs vmemmap overlap

- Swap vmalloc and Lowcore/Real Memory Copy areas in virtual memory.
This will allow to place the kernel image next to kernel modules

- Move everyting KASLR related from <asm/setup.h> to <asm/page.h>

- Put virtual memory layout information into a structure to improve
code generation

- Currently __kaslr_offset is the kernel offset in both physical and
virtual memory spaces. Uncouple these offsets to allow uncoupling of
the addresses spaces

- Currently the identity mapping base address is implicit and is always
set to zero. Make it explicit by putting into __identity_base
persistent boot variable and use it in proper context

- Introduce .amode31 section start and end macros AMODE31_START and
AMODE31_END

- Introduce OS_INFO entries that do not reference any data in memory,
but rather provide only values

- Store virtual memory layout in OS_INFO. It is read out by
makedumpfile, crash and other tools

- Store virtual memory layout in VMCORE_INFO. It is read out by crash
and other tools when /proc/kcore device is used

- Create additional PT_LOAD ELF program header that covers kernel image
only, so that vmcore tools could locate kernel text and data when
virtual and physical memory spaces are uncoupled

- Uncouple physical and virtual address spaces

- Map kernel at fixed location when KASLR mode is disabled. The
location is defined by CONFIG_KERNEL_IMAGE_BASE kernel configuration
value.

- Rework deployment of kernel image for both compressed and
uncompressed variants as defined by CONFIG_KERNEL_UNCOMPRESSED kernel
configuration value

- Move .vmlinux.relocs section in front of the compressed kernel. The
interim section rescue step is avoided as result

- Correct modules thunk offset calculation when branch target is more
than 2GB away

- Kernel modules contain their own set of expoline thunks. Now that the
kernel modules area is less than 4GB away from kernel expoline
thunks, make modules use kernel expolines. Also make EXPOLINE_EXTERN
the default if the compiler supports it

- userfaultfd can insert shared zeropages into processes running VMs,
but that is not allowed for s390. Fallback to allocating a fresh
zeroed anonymous folio and insert that instead

- Re-enable shared zeropages for non-PV and non-skeys KVM guests

- Rename hex2bitmap() to ap_hex2bitmap() and export it for external use

- Add ap_config sysfs attribute to provide the means for setting or
displaying adapters, domains and control domains assigned to a
vfio-ap mediated device in a single operation

- Make vfio_ap_mdev_link_queue() ignore duplicate link requests

- Add write support to ap_config sysfs attribute to allow atomic update
a vfio-ap mediated device state

- Document ap_config sysfs attribute

- Function os_info_old_init() is expected to be called only from a
regular kdump kernel. Enable it to be called from a stand-alone dump
kernel

- Address gcc -Warray-bounds warning and fix array size in struct
os_info

- s390 does not support SMBIOS, so drop unneeded CONFIG_DMI checks

- Use unwinder instead of __builtin_return_address() with ftrace to
prevent returning of undefined values

- Sections .hash and .gnu.hash are only created when CONFIG_PIE_BUILD
kernel is enabled. Drop these for the case CONFIG_PIE_BUILD is
disabled

- Compile kernel with -fPIC and link with -no-pie to allow kpatch
feature always succeed and drop the whole CONFIG_PIE_BUILD
option-enabled code

- Add missing virt_to_phys() converter for VSIE facility and crypto
control blocks

* tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (54 commits)
Revert "s390: Relocate vmlinux ELF data to virtual address space"
KVM: s390: vsie: Use virt_to_phys for crypto control block
s390: Relocate vmlinux ELF data to virtual address space
s390: Compile kernel with -fPIC and link with -no-pie
s390: vmlinux.lds.S: Drop .hash and .gnu.hash for !CONFIG_PIE_BUILD
s390/ftrace: Use unwinder instead of __builtin_return_address()
s390/pci: Drop unneeded reference to CONFIG_DMI
s390/os_info: Fix array size in struct os_info
s390/os_info: Initialize old os_info in standalone dump kernel
docs: Update s390 vfio-ap doc for ap_config sysfs attribute
s390/vfio-ap: Add write support to sysfs attr ap_config
s390/vfio-ap: Ignore duplicate link requests in vfio_ap_mdev_link_queue
s390/vfio-ap: Add sysfs attr, ap_config, to export mdev state
s390/ap: Externalize AP bus specific bitmap reading function
s390/mm: Re-enable the shared zeropage for !PV and !skeys KVM guests
mm/userfaultfd: Do not place zeropages when zeropages are disallowed
s390/expoline: Make modules use kernel expolines
s390/nospec: Correct modules thunk offset calculation
s390/boot: Do not rescue .vmlinux.relocs section
s390/boot: Rework deployment of the kernel image
...

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s390/mm: Uncouple physical vs virtual address spaces

The uncoupling physical vs virtual address spaces brings
the following benefits to s390:

- virtual memory layout flexibility;
- closes the addre

s390/mm: Uncouple physical vs virtual address spaces

The uncoupling physical vs virtual address spaces brings
the following benefits to s390:

- virtual memory layout flexibility;
- closes the address gap between kernel and modules, it
caused s390-only problems in the past (e.g. 'perf' bugs);
- allows getting rid of trampolines used for module calls
into kernel;
- allows simplifying BPF trampoline;
- minor performance improvement in branch prediction;
- kernel randomization entropy is magnitude bigger, as it is
derived from the amount of available virtual, not physical
memory;

The whole change could be described in two pictures below:
before and after the change.

Some aspects of the virtual memory layout setup are not
clarified (number of page levels, alignment, DMA memory),
since these are not a part of this change or secondary
with regard to how the uncoupling itself is implemented.

The focus of the pictures is to explain why __va() and __pa()
macros are implemented the way they are.

Memory layout in V==R mode:

| Physical | Virtual |
+- 0 --------------+- 0 --------------+ identity mapping start
| | S390_lowcore | Low-address memory
| +- 8 KB -----------+
| | |
| | identity | phys == virt
| | mapping | virt == phys
| | |
+- AMODE31_START --+- AMODE31_START --+ .amode31 rand. phys/virt start
|.amode31 text/data|.amode31 text/data|
+- AMODE31_END ----+- AMODE31_END ----+ .amode31 rand. phys/virt start
| | |
| | |
+- __kaslr_offset, __kaslr_offset_phys| kernel rand. phys/virt start
| | |
| kernel text/data | kernel text/data | phys == kvirt
| | |
+------------------+------------------+ kernel phys/virt end
| | |
| | |
| | |
| | |
+- ident_map_size -+- ident_map_size -+ identity mapping end
| |
| ... unused gap |
| |
+---- vmemmap -----+ 'struct page' array start
| |
| virtually mapped |
| memory map |
| |
+- __abs_lowcore --+
| |
| Absolute Lowcore |
| |
+- __memcpy_real_area
| |
| Real Memory Copy|
| |
+- VMALLOC_START --+ vmalloc area start
| |
| vmalloc area |
| |
+- MODULES_VADDR --+ modules area start
| |
| modules area |
| |
+------------------+ UltraVisor Secure Storage limit
| |
| ... unused gap |
| |
+KASAN_SHADOW_START+ KASAN shadow memory start
| |
| KASAN shadow |
| |
+------------------+ ASCE limit

Memory layout in V!=R mode:

| Physical | Virtual |
+- 0 --------------+- 0 --------------+
| | S390_lowcore | Low-address memory
| +- 8 KB -----------+
| | |
| | |
| | ... unused gap |
| | |
+- AMODE31_START --+- AMODE31_START --+ .amode31 rand. phys/virt start
|.amode31 text/data|.amode31 text/data|
+- AMODE31_END ----+- AMODE31_END ----+ .amode31 rand. phys/virt end (<2GB)
| | |
| | |
+- __kaslr_offset_phys | kernel rand. phys start
| | |
| kernel text/data | |
| | |
+------------------+ | kernel phys end
| | |
| | |
| | |
| | |
+- ident_map_size -+ |
| |
| ... unused gap |
| |
+- __identity_base + identity mapping start (>= 2GB)
| |
| identity | phys == virt - __identity_base
| mapping | virt == phys + __identity_base
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
+---- vmemmap -----+ 'struct page' array start
| |
| virtually mapped |
| memory map |
| |
+- __abs_lowcore --+
| |
| Absolute Lowcore |
| |
+- __memcpy_real_area
| |
| Real Memory Copy|
| |
+- VMALLOC_START --+ vmalloc area start
| |
| vmalloc area |
| |
+- MODULES_VADDR --+ modules area start
| |
| modules area |
| |
+- __kaslr_offset -+ kernel rand. virt start
| |
| kernel text/data | phys == (kvirt - __kaslr_offset) +
| | __kaslr_offset_phys
+- kernel .bss end + kernel rand. virt end
| |
| ... unused gap |
| |
+------------------+ UltraVisor Secure Storage limit
| |
| ... unused gap |
| |
+KASAN_SHADOW_START+ KASAN shadow memory start
| |
| KASAN shadow |
| |
+------------------+ ASCE limit

Unused gaps in the virtual memory layout could be present
or not - depending on how partucular system is configured.
No page tables are created for the unused gaps.

The relative order of vmalloc, modules and kernel image in
virtual memory is defined by following considerations:

- start of the modules area and end of the kernel should reside
within 4GB to accommodate relative 32-bit jumps. The best way
to achieve that is to place kernel next to modules;

- vmalloc and module areas should locate next to each other
to prevent failures and extra reworks in user level tools
(makedumpfile, crash, etc.) which treat vmalloc and module
addresses similarily;

- kernel needs to be the last area in the virtual memory
layout to easily distinguish between kernel and non-kernel
virtual addresses. That is needed to (again) simplify
handling of addresses in user level tools and make __pa()
macro faster (see below);

Concluding the above, the relative order of the considered
virtual areas in memory is: vmalloc - modules - kernel.
Therefore, the only change to the current memory layout is
moving kernel to the end of virtual address space.

With that approach the implementation of __pa() macro is
straightforward - all linear virtual addresses less than
kernel base are considered identity mapping:

phys == virt - __identity_base

All addresses greater than kernel base are kernel ones:

phys == (kvirt - __kaslr_offset) + __kaslr_offset_phys

By contrast, __va() macro deals only with identity mapping
addresses:

virt == phys + __identity_base

.amode31 section is mapped separately and is not covered by
__pa() macro. In fact, it could have been handled easily by
checking whether a virtual address is within the section or
not, but there is no need for that. Thus, let __pa() code
do as little machine cycles as possible.

The KASAN shadow memory is located at the very end of the
virtual memory layout, at addresses higher than the kernel.
However, that is not a linear mapping and no code other than
KASAN instrumentation or API is expected to access it.

When KASLR mode is enabled the kernel base address randomized
within a memory window that spans whole unused virtual address
space. The size of that window depends from the amount of
physical memory available to the system, the limit imposed by
UltraVisor (if present) and the vmalloc area size as provided
by vmalloc= kernel command line parameter.

In case the virtual memory is exhausted the minimum size of
the randomization window is forcefully set to 2GB, which
amounts to in 15 bits of entropy if KASAN is enabled or 17
bits of entropy in default configuration.

The default kernel offset 0x100000 is used as a magic value
both in the decompressor code and vmlinux linker script, but
it will be removed with a follow-up change.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

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