s390/boot: rename mem_detect to physmem_info

In preparation to extending mem_detect with additional information like
reserved ranges rename it to more generic physmem_info. This new naming
also help

s390/boot: rename mem_detect to physmem_info

In preparation to extending mem_detect with additional information like
reserved ranges rename it to more generic physmem_info. This new naming
also help to avoid confusion by using more exact terms like "physmem
online ranges", etc.

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

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s390/decompressor: add link map saving

Produce arch/s390/boot/vmlinux.map link map for the decompressor, when
CONFIG_VMLINUX_MAP option is enabled.

Link map is quite useful during making kernel cha

s390/decompressor: add link map saving

Produce arch/s390/boot/vmlinux.map link map for the decompressor, when
CONFIG_VMLINUX_MAP option is enabled.

Link map is quite useful during making kernel changes related to how
the decompressor is composed and debugging linker scripts.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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s390/mm: start kernel with DAT enabled

The setup of the kernel virtual address space is spread
throughout the sources, boot stages and config options
like this:

1. The available physical memory reg

s390/mm: start kernel with DAT enabled

The setup of the kernel virtual address space is spread
throughout the sources, boot stages and config options
like this:

1. The available physical memory regions are queried
and stored as mem_detect information for later use
in the decompressor.

2. Based on the physical memory availability the virtual
memory layout is established in the decompressor;

3. If CONFIG_KASAN is disabled the kernel paging setup
code populates kernel pgtables and turns DAT mode on.
It uses the information stored at step [1].

4. If CONFIG_KASAN is enabled the kernel early boot
kasan setup populates kernel pgtables and turns DAT
mode on. It uses the information stored at step [1].

The kasan setup creates early_pg_dir directory and
directly overwrites swapper_pg_dir entries to make
shadow memory pages available.

Move the kernel virtual memory setup to the decompressor
and start the kernel with DAT turned on right from the
very first istruction. That completely eliminates the
boot phase when the kernel runs in DAT-off mode, simplies
the overall design and consolidates pgtables setup.

The identity mapping is created in the decompressor, while
kasan shadow mappings are still created by the early boot
kernel code.

Share with decompressor the existing kasan memory allocator.
It decreases the size of a newly requested memory block from
pgalloc_pos and ensures that kernel image is not overwritten.
pgalloc_low and pgalloc_pos pointers are made preserved boot
variables for that.

Use the bootdata infrastructure to setup swapper_pg_dir
and invalid_pg_dir directories used by the kernel later.
The interim early_pg_dir directory established by the
kasan initialization code gets eliminated as result.

As the kernel runs in DAT-on mode only the PSW_KERNEL_BITS
define gets PSW_MASK_DAT bit by default. Additionally, the
setup_lowcore_dat_off() and setup_lowcore_dat_on() routines
get merged, since there is no DAT-off mode stage anymore.

The memory mappings are created with RW+X protection that
allows the early boot code setting up all necessary data
and services for the kernel being booted. Just before the
paging is enabled the memory protection is changed to
RO+X for text, RO+NX for read-only data and RW+NX for
kernel data and the identity mapping.

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

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s390: always build relocatable kernel

Nathan Chancellor reported several link errors on s390 with
CONFIG_RELOCATABLE disabled, after binutils commit 906f69cf65da ("IBM
zSystems: Issue error for *DBL

s390: always build relocatable kernel

Nathan Chancellor reported several link errors on s390 with
CONFIG_RELOCATABLE disabled, after binutils commit 906f69cf65da ("IBM
zSystems: Issue error for *DBL relocs on misaligned symbols"). The binutils
commit reveals potential miscompiles that might have happened already
before with linker script defined symbols at odd addresses.

A similar bug was recently fixed in the kernel with commit c9305b6c1f52
("s390: fix nospec table alignments").

See https://github.com/ClangBuiltLinux/linux/issues/1747 for an analysis
from Ulich Weigand.

Therefore always build a relocatable kernel to avoid this problem. There is
hardly any use-case for non-relocatable kernels, so this shouldn't be
controversial.

Link: https://github.com/ClangBuiltLinux/linux/issues/1747
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20221030182202.2062705-1-hca@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

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s390/boot: convert initial lowcore to C

Convert initial lowcore to C and use proper defines and structures to
initialize it. This should make the z/VM ipl procedure a bit less magic.

Acked-by: Pete

s390/boot: convert initial lowcore to C

Convert initial lowcore to C and use proper defines and structures to
initialize it. This should make the z/VM ipl procedure a bit less magic.

Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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s390/boot: get rid of startup archive

The final kernel image is created by linking decompressor object files with
a startup archive. The startup archive file however does not contain only
optional c

s390/boot: get rid of startup archive

The final kernel image is created by linking decompressor object files with
a startup archive. The startup archive file however does not contain only
optional code and data which can be discarded if not referenced. It also
contains mandatory object data like head.o which must never be discarded,
even if not referenced.

Move the decompresser code and linker script to the boot directory and get
rid of the startup archive so everything is kept during link time.

Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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s390: move the install rule to arch/s390/Makefile

Currently, the install target in arch/s390/Makefile descends into
arch/s390/boot/Makefile to invoke the shell script, but there is no
good reason to

s390: move the install rule to arch/s390/Makefile

Currently, the install target in arch/s390/Makefile descends into
arch/s390/boot/Makefile to invoke the shell script, but there is no
good reason to do so.

arch/s390/Makefile can run the shell script directly.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20210729142338.446002-1-masahiroy@kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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s390: enable KCSAN

s390x GCC and SystemZ Clang have ThreadSanitizer support now [1] [2],
so enable KCSAN for s390.

[1] https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=ea22954e7c58
[2] https://reviews

s390: enable KCSAN

s390x GCC and SystemZ Clang have ThreadSanitizer support now [1] [2],
so enable KCSAN for s390.

[1] https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=ea22954e7c58
[2] https://reviews.llvm.org/D105629

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

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s390/boot: move dma sections from decompressor to decompressed kernel

This change simplifies the task of making the decompressor relocatable.

The decompressor's image contains special DMA sections

s390/boot: move dma sections from decompressor to decompressed kernel

This change simplifies the task of making the decompressor relocatable.

The decompressor's image contains special DMA sections between _sdma and
_edma. This DMA segment is loaded at boot as part of the decompressor and
then simply handed over to the decompressed kernel. The decompressor itself
never uses it in any way. The primary reason for this is the need to keep
the aforementioned DMA segment below 2GB which is required by architecture,
and because the decompressor is always loaded at a fixed low physical
address, it is guaranteed that the DMA region will not cross the 2GB
memory limit. If the DMA region had been placed in the decompressed kernel,
then KASLR would make this guarantee impossible to fulfill or it would
be restricted to the first 2GB of memory address space.

This commit moves all DMA sections between _sdma and _edma from
the decompressor's image to the decompressed kernel's image. The complete
DMA region is placed in the init section of the decompressed kernel and
immediately relocated below 2GB at start-up before it is needed by other
parts of the decompressed kernel. The relocation of the DMA region happens
even if the decompressed kernel is already located below 2GB in order
to keep the first implementation simple. The relocation should not have
any noticeable impact on boot time because the DMA segment is only a couple
of pages.

After relocating the DMA sections, the kernel has to fix all references
which point into it. In order to automate this, place all variables
pointing into the DMA sections in a special .dma.refs section. All such
variables must be defined using the new __dma_ref macro. Only variables
containing addresses within the DMA sections must be placed in the new
.dma.refs section.

Furthermore, move the initialization of control registers from
the decompressor to the decompressed kernel because some control registers
reference tables that must be placed in the DMA data section to
guarantee that their addresses are below 2G. Because the decompressed
kernel relocates the DMA sections at startup, the content of control
registers CR2, CR5 and CR15 must be updated with new addresses after
the relocation. The decompressed kernel initializes all control registers
early at boot and then updates the content of CR2, CR5 and CR15
as soon as the DMA relocation has occurred. This practically reverts
the commit a80313ff91ab ("s390/kernel: introduce .dma sections").

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

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s390/boot: enable .bss section for compressed kernel

- Support static uninitialized variables in compressed kernel.
- Remove chkbss script
- Get rid of workarounds for not having .bss section

Signe

s390/boot: enable .bss section for compressed kernel

- Support static uninitialized variables in compressed kernel.
- Remove chkbss script
- Get rid of workarounds for not having .bss section

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

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s390/protvirt: introduce host side setup

Add "prot_virt" command line option which controls if the kernel
protected VMs support is enabled at early boot time. This has to be
done early, because it n

s390/protvirt: introduce host side setup

Add "prot_virt" command line option which controls if the kernel
protected VMs support is enabled at early boot time. This has to be
done early, because it needs large amounts of memory and will disable
some features like STP time sync for the lpar.

Extend ultravisor info definitions and expose it via uv_info struct
filled in during startup.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

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s390: make 'install' not depend on vmlinux

For the same reason as commit 19514fc665ff ("arm, kbuild: make "make
install" not depend on vmlinux"), the install targets should never
trigger the rebuild

s390: make 'install' not depend on vmlinux

For the same reason as commit 19514fc665ff ("arm, kbuild: make "make
install" not depend on vmlinux"), the install targets should never
trigger the rebuild of the kernel.

The variable, CONFIGURE, is not set by anyone. Remove it as well.

Link: https://lkml.kernel.org/r/20200216144829.27023-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

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s390/startup: add pgm check info printing

Try to print out startup pgm check info including exact linux kernel
version, pgm interruption code and ilc, psw and general registers. Like
the following:

s390/startup: add pgm check info printing

Try to print out startup pgm check info including exact linux kernel
version, pgm interruption code and ilc, psw and general registers. Like
the following:

Linux version 5.3.0-rc7-07282-ge7b4d41d61bd-dirty (gor@tuxmaker) #3 SMP PREEMPT Thu Sep 5 16:07:34 CEST 2019
Kernel fault: interruption code 0005 ilc:2
PSW : 0000000180000000 0000000000012e52
R:0 T:0 IO:0 EX:0 Key:0 M:0 W:0 P:0 AS:0 CC:0 PM:0 RI:0 EA:3
GPRS: 0000000000000000 00ffffffffffffff 0000000000000000 0000000000019a58
000000000000bf68 0000000000000000 0000000000000000 0000000000000000
0000000000000000 0000000000000000 000000000001a041 0000000000000000
0000000004c9c000 0000000000010070 0000000000012e42 000000000000beb0

This info makes it apparent that kernel startup failed and might help
to understand what went wrong without actual standalone dump.

Printing code runs on its own stack of 1 page (at unused 0x5000), which
should be sufficient for sclp_early_printk usage (typical stack usage
observed has been around 512 bytes).

The code has pgm check recursion prevention, despite pgm check info
printing failure (follow on pgm check) or success it restores original
faulty psw and gprs and does disabled wait.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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s390: enable detection of kernel version from bzImage

Extend "parmarea" to include an offset of the version string, which is
stored as 8-byte big endian value.

To retrieve version string from bzIma

s390: enable detection of kernel version from bzImage

Extend "parmarea" to include an offset of the version string, which is
stored as 8-byte big endian value.

To retrieve version string from bzImage reliably, one should check the
presence of "S390EP" ascii string at 0x10008 (available since v3.2),
then read the version string offset from 0x10428 (which has been 0
since v3.2 up to now). The string is null terminated.

Could be retrieved with the following "file" command magic (requires
file v5.34):
8 string \x02\x00\x00\x18\x60\x00\x00\x50\x02\x00\x00\x68\x60\x00\x00\x50\x40\x40\x40\x40\x40\x40\x40\x40 Linux S390
>0x10008 string S390EP
>>0x10428 bequad >0
>>>(0x10428.Q) string >\0 \b, version %s

Reported-by: Petr Tesarik <ptesarik@suse.com>
Suggested-by: Petr Tesarik <ptesarik@suse.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

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s390/boot: fix compiler error due to missing awk strtonum

The strtonum awk function is a GNU extension and is not available with
all versions of awk. The link of bzImage fails with this error messag

s390/boot: fix compiler error due to missing awk strtonum

The strtonum awk function is a GNU extension and is not available with
all versions of awk. The link of bzImage fails with this error message:

>> awk: line 2: function or never defined
>> awk: line 2: function strtonum never defined
objcopy: --pad-to: bad number: arch/s390/boot/compressed/vmlinux

Drop the awk script and the --pad-to objcopy parameter it generated and
use a FILL pattern with an appropriate alignment in the linker script
for the arch/s390/boot/compressed/vmlinux file.

Fixes: f6780686525c ("s390/boot: pad bzImage to 4K")
Reported-by: kbuild test robot <lkp@intel.com>
Suggested-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390: only build for new CPUs with clang

llvm does does not understand -march=z9-109 and older target
specifiers, so disable the respective Kconfig settings and
the logic to make the boot code work

s390: only build for new CPUs with clang

llvm does does not understand -march=z9-109 and older target
specifiers, so disable the respective Kconfig settings and
the logic to make the boot code work on old systems when
building with clang.

Part of the early boot code is normally compiled with -march=z900
for maximum compatibility. This also has to get changed with
clang to the oldest supported ISA, which is -march=z10 here.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/kernel: add support for kernel address space layout randomization (KASLR)

This patch adds support for relocating the kernel to a random address.
The random kernel offset is obtained from cpacf,

s390/kernel: add support for kernel address space layout randomization (KASLR)

This patch adds support for relocating the kernel to a random address.
The random kernel offset is obtained from cpacf, using either TRNG, PRNO,
or KMC_PRNG, depending on supported MSA level.

KERNELOFFSET is added to vmcoreinfo, for crash --kaslr support.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/kernel: introduce .dma sections

With a relocatable kernel that could reside at any place in memory, code
and data that has to stay below 2 GB needs special handling.

This patch introduces .dma

s390/kernel: introduce .dma sections

With a relocatable kernel that could reside at any place in memory, code
and data that has to stay below 2 GB needs special handling.

This patch introduces .dma sections for such text, data and ex_table.
The sections will be part of the decompressor kernel, so they will not
be relocated and stay below 2 GB. Their location is passed over to the
decompressed / relocated kernel via the .boot.preserved.data section.

The duald and aste for control register setup also need to stay below
2 GB, so move the setup code from arch/s390/kernel/head64.S to
arch/s390/boot/head.S. The duct and linkage_stack could reside above
2 GB, but their content has to be preserved for the decompresed kernel,
so they are also moved into the .dma section.

The start and end address of the .dma sections is added to vmcoreinfo,
for crash support, to help debugging in case the kernel crashed there.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/kernel: build a relocatable kernel

This patch adds support for building a relocatable kernel with -fPIE.
The kernel will be relocated to 0 early in the boot process.

Signed-off-by: Gerald Scha

s390/kernel: build a relocatable kernel

This patch adds support for building a relocatable kernel with -fPIE.
The kernel will be relocated to 0 early in the boot process.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/boot: pad bzImage to 4K

In order to be able to sign the bzImage independent of the block size
of the IPL device, align the bzImage to 4096 bytes.

Signed-off-by: Martin Schwidefsky <schwidefsky

s390/boot: pad bzImage to 4K

In order to be able to sign the bzImage independent of the block size
of the IPL device, align the bzImage to 4096 bytes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/ipl: read IPL report at early boot

Read the IPL Report block provided by secure-boot, add the entries
of the certificate list to the system key ring and print the list
of components.

PR: Adjus

s390/ipl: read IPL report at early boot

Read the IPL Report block provided by secure-boot, add the entries
of the certificate list to the system key ring and print the list
of components.

PR: Adjust to Vasilys bootdata_preserved patch set. Preserve ipl_cert_list
for later use in kexec_file.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390/uv: introduce guest side ultravisor code

The Ultravisor Call Facility (stfle bit 158) defines an API to the
Ultravisor (UV calls), a mini hypervisor located at machine
level. With help of the U

s390/uv: introduce guest side ultravisor code

The Ultravisor Call Facility (stfle bit 158) defines an API to the
Ultravisor (UV calls), a mini hypervisor located at machine
level. With help of the Ultravisor, KVM will be able to run
"protected" VMs, special VMs whose memory and management data are
unavailable to KVM.

The protected VMs can also request services from the Ultravisor.
The guest api consists of UV calls to share and unshare memory with the
kvm hypervisor.

To enable this feature support PROTECTED_VIRTUALIZATION_GUEST kconfig
option has been introduced.

Co-developed-by: Janosch Frank <frankja@de.ibm.com>
Signed-off-by: Janosch Frank <frankja@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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s390: introduce .boot.preserved.data section compile time validation

Same as for .boot.data section make sure that .boot.preserved.data
sections of vmlinux and arch/s390/compressed/vmlinux match bef

s390: introduce .boot.preserved.data section compile time validation

Same as for .boot.data section make sure that .boot.preserved.data
sections of vmlinux and arch/s390/compressed/vmlinux match before
producing the compressed kernel image. Symbols presence, order and sizes
are cross-checked.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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kbuild: move archive command to scripts/Makefile.lib

scripts/Makefile.build and arch/s390/boot/Makefile use the same
command (thin archiving with symbol table creation).

Avoid the code duplication,

kbuild: move archive command to scripts/Makefile.lib

scripts/Makefile.build and arch/s390/boot/Makefile use the same
command (thin archiving with symbol table creation).

Avoid the code duplication, and move it to scripts/Makefile.lib.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

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kbuild: add real-prereqs shorthand for $(filter-out FORCE,$^)

In Kbuild, if_changed and friends must have FORCE as a prerequisite.

Hence, $(filter-out FORCE,$^) or $(filter-out $(PHONY),$^) is a co

kbuild: add real-prereqs shorthand for $(filter-out FORCE,$^)

In Kbuild, if_changed and friends must have FORCE as a prerequisite.

Hence, $(filter-out FORCE,$^) or $(filter-out $(PHONY),$^) is a common
idiom to get the names of all the prerequisites except phony targets.

Add real-prereqs as a shorthand.

Note:
We cannot replace $(filter %.o,$^) in cmd_link_multi-m because $^ may
include auto-generated dependencies from the .*.cmd file when a single
object module is changed into a multi object module. Refer to commit
69ea912fda74 ("kbuild: remove unneeded link_multi_deps"). I added some
comment to avoid accidental breakage.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Rob Herring <robh@kernel.org>

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