CONFIG_RANDOMIZE_IDENTITY_BASE only enables support for randomizing the
identity mapping base. The randomization (identity base != 0) itself
should happen only when KASLR is enabled at runtime.
Guard the __identity_base update with kaslr_enabled() so nokaslr (and
other KASLR-disabled cases) keep the non-randomized identity mapping at 0.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
- Drop support for outdated 3590/3592 and 3480 tape devices, and limit
support to virtualized 3490E types devices
- Implement exception based WARN() and WARN_ONCE() similar to x86
- Slightly optimize preempt primitives like __preempt_count_add() and
__preempt_count_dec_and_test()
- A couple of small fixes and improvements
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Merge tag 's390-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Heiko Carstens:
- Drop support for outdated 3590/3592 and 3480 tape devices, and limit
support to virtualized 3490E types devices
- Implement exception based WARN() and WARN_ONCE() similar to x86
- Slightly optimize preempt primitives like __preempt_count_add() and
__preempt_count_dec_and_test()
- A couple of small fixes and improvements
* tag 's390-7.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (35 commits)
s390/tape: Consolidate tape config options and modules
s390/cio: Fix device lifecycle handling in css_alloc_subchannel()
s390/tape: Rename tape_34xx.c to tape_3490.c
s390/tape: Cleanup sense data analysis and error handling
s390/tape: Remove 3480 tape device type
s390/tape: Remove unused command definitions
s390/tape: Remove special block id handling
s390/tape: Remove tape load display support
s390/tape: Remove support for 3590/3592 models
s390/kexec: Emit an error message when cmdline is too long
s390/configs: Enable BLK_DEV_NULL_BLK as module
s390: Document s390 stackprotector support
s390/perf: Disable register readout on sampling events
s390/Kconfig: Define non-zero ILLEGAL_POINTER_VALUE
s390/bug: Prevent tail-call optimization
s390/bug: Skip __WARN_trap() in call traces
s390/bug: Implement WARN_ONCE()
s390/bug: Implement __WARN_printf()
s390/traps: Copy monitor code to pt_regs
s390/bug: Introduce and use monitor code macro
...
Define CONFIG_ILLEGAL_POINTER_VALUE to the eye-catching non-zero value
of 0xdead000000000000, consistent with other architectures. Assert at
compile-time that the poison pointers that include/linux/poison.h
defines based on this illegal pointer are beyond the largest useful
virtual addresses. Also, assert at compile-time that the range of poison
pointers per include/linux/poison.h (currently a range of less than
0x10000 addresses) does not overlap with the range used for address
handles for s390's non-MIO PCI instructions.
This enables s390 to track the DMA mappings by the network stack's
page_pool that was introduced with [0]. Other functional changes are not
intended.
Other archictectures have introduced this for various other reasons with
commit 5c178472af ("riscv: define ILLEGAL_POINTER_VALUE for 64bit")
commit f6853eb561 ("powerpc/64: Define ILLEGAL_POINTER_VALUE for 64-bit")
commit bf0c4e0473 ("arm64: kconfig: Move LIST_POISON to a safe value")
commit a29815a333 ("core, x86: make LIST_POISON less deadly")
[0] https://lore.kernel.org/all/20250409-page-pool-track-dma-v9-0-6a9ef2e0cba8@redhat.com/
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Since commit 3e86e4d74c ("kbuild: keep .modinfo section in
vmlinux.unstripped") the .modinfo section which has SHF_ALLOC ends up
in bzImage after the SecureBoot trailer. This breaks SecureBoot because
the bootloader can no longer find the SecureBoot trailer with kernel's
signature at the expected location in bzImage. To fix the bug,
move discarded sections before the ELF_DETAILS macro and discard
the .modinfo section which is not needed by the decompressor.
Fixes: 3e86e4d74c ("kbuild: keep .modinfo section in vmlinux.unstripped")
Cc: stable@vger.kernel.org
Suggested-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Tested-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Add -Wno-default-const-init-unsafe to boot KBUILD_CFLAGS, similar to
scripts/Makefile.extrawarn, since clang generates warnings for the dummy
variable in typecheck():
CC arch/s390/boot/version.o
arch/s390/include/asm/ptrace.h:221:9: warning: default initialization of an object of type 'typeof (regs->psw)' (aka 'const psw_t') leaves the object uninitialized [-Wdefault-const-init-var-unsafe]
221 | return psw_bits(regs->psw).pstate;
| ^
arch/s390/include/asm/ptrace.h:98:2: note: expanded from macro 'psw_bits'
98 | typecheck(psw_t, __psw); \
| ^
include/linux/typecheck.h:11:12: note: expanded from macro 'typecheck'
11 | typeof(x) __dummy2; \
| ^
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Make boot_pte_alloc() always allocate a full PAGE_SIZE page for
PTE tables, instead of carving two 2K PTE tables out of a single
4K page, similar to commit daa8af80d2 ("s390/mm: Allocate page
table with PAGE_SIZE granularity").
This mirrors the change in the vmem code and ensures that boot page
tables backing the early KASAN shadow can later be fully freed by
the vmem page-table teardown helpers (e.g. when unmapping early
KASAN shadow on memory hotplug).
The leftover-based allocation was originally added to reduce physmem
allocator fragmentation when EDAT was disabled. On current hardware
EDAT1 is available on all production systems, so the complexity is no
longer justified and gets in the way of freeing the shadow mappings.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
- The 10 patch series "__vmalloc()/kvmalloc() and no-block support" from
Uladzislau Rezki reworks the vmalloc() code to support non-blocking
allocations (GFP_ATOIC, GFP_NOWAIT).
- The 2 patch series "ksm: fix exec/fork inheritance" from xu xin fixes
a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited
across fork/exec.
- The 4 patch series "mm/zswap: misc cleanup of code and documentations"
from SeongJae Park does some light maintenance work on the zswap code.
- The 5 patch series "mm/page_owner: add debugfs files 'show_handles'
and 'show_stacks_handles'" from Mauricio Faria de Oliveira enhances the
/sys/kernel/debug/page_owner debug feature. It adds unique identifiers
to differentiate the various stack traces so that userspace monitoring
tools can better match stack traces over time.
- The 2 patch series "mm/page_alloc: pcp->batch cleanups" from Joshua
Hahn makes some minor alterations to the page allocator's per-cpu-pages
feature.
- The 2 patch series "Improve UFFDIO_MOVE scalability by removing
anon_vma lock" from Lokesh Gidra addresses a scalability issue in
userfaultfd's UFFDIO_MOVE operation.
- The 2 patch series "kasan: cleanups for kasan_enabled() checks" from
Sabyrzhan Tasbolatov performs some cleanup in the KASAN code.
- The 2 patch series "drivers/base/node: fold node register and
unregister functions" from Donet Tom cleans up the NUMA node handling
code a little.
- The 4 patch series "mm: some optimizations for prot numa" from Kefeng
Wang provides some cleanups and small optimizations to the NUMA
allocation hinting code.
- The 5 patch series "mm/page_alloc: Batch callers of
free_pcppages_bulk" from Joshua Hahn addresses long lock hold times at
boot on large machines. These were causing (harmless) softlockup
warnings.
- The 2 patch series "optimize the logic for handling dirty file folios
during reclaim" from Baolin Wang removes some now-unnecessary work from
page reclaim.
- The 10 patch series "mm/damon: allow DAMOS auto-tuned for per-memcg
per-node memory usage" from SeongJae Park enhances the DAMOS auto-tuning
feature.
- The 2 patch series "mm/damon: fixes for address alignment issues in
DAMON_LRU_SORT and DAMON_RECLAIM" from Quanmin Yan fixes DAMON_LRU_SORT
and DAMON_RECLAIM with certain userspace configuration.
- The 15 patch series "expand mmap_prepare functionality, port more
users" from Lorenzo Stoakes enhances the new(ish)
file_operations.mmap_prepare() method and ports additional callsites
from the old ->mmap() over to ->mmap_prepare().
- The 8 patch series "Fix stale IOTLB entries for kernel address space"
from Lu Baolu fixes a bug (and possible security issue on non-x86) in
the IOMMU code. In some situations the IOMMU could be left hanging onto
a stale kernel pagetable entry.
- The 4 patch series "mm/huge_memory: cleanup __split_unmapped_folio()"
from Wei Yang cleans up and optimizes the folio splitting code.
- The 5 patch series "mm, swap: misc cleanup and bugfix" from Kairui
Song implements some cleanups and a minor fix in the swap discard code.
- The 8 patch series "mm/damon: misc documentation fixups" from SeongJae
Park does as advertised.
- The 9 patch series "mm/damon: support pin-point targets removal" from
SeongJae Park permits userspace to remove a specific monitoring target
in the middle of the current targets list.
- The 2 patch series "mm: MISC follow-up patches for linux/pgalloc.h"
from Harry Yoo implements a couple of cleanups related to mm header file
inclusion.
- The 2 patch series "mm/swapfile.c: select swap devices of default
priority round robin" from Baoquan He improves the selection of swap
devices for NUMA machines.
- The 3 patch series "mm: Convert memory block states (MEM_*) macros to
enums" from Israel Batista changes the memory block labels from macros
to enums so they will appear in kernel debug info.
- The 3 patch series "ksm: perform a range-walk to jump over holes in
break_ksm" from Pedro Demarchi Gomes addresses an inefficiency when KSM
unmerges an address range.
- The 22 patch series "mm/damon/tests: fix memory bugs in kunit tests"
from SeongJae Park fixes leaks and unhandled malloc() failures in DAMON
userspace unit tests.
- The 2 patch series "some cleanups for pageout()" from Baolin Wang
cleans up a couple of minor things in the page scanner's
writeback-for-eviction code.
- The 2 patch series "mm/hugetlb: refactor sysfs/sysctl interfaces" from
Hui Zhu moves hugetlb's sysfs/sysctl handling code into a new file.
- The 9 patch series "introduce VM_MAYBE_GUARD and make it sticky" from
Lorenzo Stoakes makes the VMA guard regions available in /proc/pid/smaps
and improves the mergeability of guarded VMAs.
- The 2 patch series "mm: perform guard region install/remove under VMA
lock" from Lorenzo Stoakes reduces mmap lock contention for callers
performing VMA guard region operations.
- The 2 patch series "vma_start_write_killable" from Matthew Wilcox
starts work in permitting applications to be killed when they are
waiting on a read_lock on the VMA lock.
- The 11 patch series "mm/damon/tests: add more tests for online
parameters commit" from SeongJae Park adds additional userspace testing
of DAMON's "commit" feature.
- The 9 patch series "mm/damon: misc cleanups" from SeongJae Park does
that.
- The 2 patch series "make VM_SOFTDIRTY a sticky VMA flag" from Lorenzo
Stoakes addresses the possible loss of a VMA's VM_SOFTDIRTY flag when
that VMA is merged with another.
- The 16 patch series "mm: support device-private THP" from Balbir Singh
introduces support for Transparent Huge Page (THP) migration in zone
device-private memory.
- The 3 patch series "Optimize folio split in memory failure" from Zi
Yan optimizes folio split operations in the memory failure code.
- The 2 patch series "mm/huge_memory: Define split_type and consolidate
split support checks" from Wei Yang provides some more cleanups in the
folio splitting code.
- The 16 patch series "mm: remove is_swap_[pte, pmd]() + non-swap
entries, introduce leaf entries" from Lorenzo Stoakes cleans up our
handling of pagetable leaf entries by introducing the concept of
'software leaf entries', of type softleaf_t.
- The 4 patch series "reparent the THP split queue" from Muchun Song
reparents the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory resources.
- The 3 patch series "unify PMD scan results and remove redundant
cleanup" from Wei Yang does a little cleanup in the hugepage collapse
code.
- The 6 patch series "zram: introduce writeback bio batching" from
Sergey Senozhatsky improves zram writeback efficiency by introducing
batched bio writeback support.
- The 4 patch series "memcg: cleanup the memcg stats interfaces" from
Shakeel Butt cleans up our handling of the interrupt safety of some
memcg stats.
- The 4 patch series "make vmalloc gfp flags usage more apparent" from
Vishal Moola cleans up vmalloc's handling of incoming GFP flags.
- The 6 patch series "mm: Add soft-dirty and uffd-wp support for RISC-V"
from Chunyan Zhang teches soft dirty and userfaultfd write protect
tracking to use RISC-V's Svrsw60t59b extension.
- The 5 patch series "mm: swap: small fixes and comment cleanups" from
Youngjun Park fixes a small bug and cleans up some of the swap code.
- The 4 patch series "initial work on making VMA flags a bitmap" from
Lorenzo Stoakes starts work on converting the vma struct's flags to a
bitmap, so we stop running out of them, especially on 32-bit.
- The 2 patch series "mm/swapfile: fix and cleanup swap list iterations"
from Youngjun Park addresses a possible bug in the swap discard code and
cleans things up a little.
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Merge tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
Rework the vmalloc() code to support non-blocking allocations
(GFP_ATOIC, GFP_NOWAIT)
"ksm: fix exec/fork inheritance" (xu xin)
Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
inherited across fork/exec
"mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
Some light maintenance work on the zswap code
"mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
Enhance the /sys/kernel/debug/page_owner debug feature by adding
unique identifiers to differentiate the various stack traces so
that userspace monitoring tools can better match stack traces over
time
"mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
Minor alterations to the page allocator's per-cpu-pages feature
"Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
Address a scalability issue in userfaultfd's UFFDIO_MOVE operation
"kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)
"drivers/base/node: fold node register and unregister functions" (Donet Tom)
Clean up the NUMA node handling code a little
"mm: some optimizations for prot numa" (Kefeng Wang)
Cleanups and small optimizations to the NUMA allocation hinting
code
"mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
Address long lock hold times at boot on large machines. These were
causing (harmless) softlockup warnings
"optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
Remove some now-unnecessary work from page reclaim
"mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
Enhance the DAMOS auto-tuning feature
"mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
configuration
"expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
Enhance the new(ish) file_operations.mmap_prepare() method and port
additional callsites from the old ->mmap() over to ->mmap_prepare()
"Fix stale IOTLB entries for kernel address space" (Lu Baolu)
Fix a bug (and possible security issue on non-x86) in the IOMMU
code. In some situations the IOMMU could be left hanging onto a
stale kernel pagetable entry
"mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
Clean up and optimize the folio splitting code
"mm, swap: misc cleanup and bugfix" (Kairui Song)
Some cleanups and a minor fix in the swap discard code
"mm/damon: misc documentation fixups" (SeongJae Park)
"mm/damon: support pin-point targets removal" (SeongJae Park)
Permit userspace to remove a specific monitoring target in the
middle of the current targets list
"mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
A couple of cleanups related to mm header file inclusion
"mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
improve the selection of swap devices for NUMA machines
"mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
Change the memory block labels from macros to enums so they will
appear in kernel debug info
"ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
Address an inefficiency when KSM unmerges an address range
"mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
Fix leaks and unhandled malloc() failures in DAMON userspace unit
tests
"some cleanups for pageout()" (Baolin Wang)
Clean up a couple of minor things in the page scanner's
writeback-for-eviction code
"mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
Move hugetlb's sysfs/sysctl handling code into a new file
"introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
Make the VMA guard regions available in /proc/pid/smaps and
improves the mergeability of guarded VMAs
"mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
Reduce mmap lock contention for callers performing VMA guard region
operations
"vma_start_write_killable" (Matthew Wilcox)
Start work on permitting applications to be killed when they are
waiting on a read_lock on the VMA lock
"mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
Add additional userspace testing of DAMON's "commit" feature
"mm/damon: misc cleanups" (SeongJae Park)
"make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
VMA is merged with another
"mm: support device-private THP" (Balbir Singh)
Introduce support for Transparent Huge Page (THP) migration in zone
device-private memory
"Optimize folio split in memory failure" (Zi Yan)
"mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
Some more cleanups in the folio splitting code
"mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
Clean up our handling of pagetable leaf entries by introducing the
concept of 'software leaf entries', of type softleaf_t
"reparent the THP split queue" (Muchun Song)
Reparent the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory
resources
"unify PMD scan results and remove redundant cleanup" (Wei Yang)
A little cleanup in the hugepage collapse code
"zram: introduce writeback bio batching" (Sergey Senozhatsky)
Improve zram writeback efficiency by introducing batched bio
writeback support
"memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
Clean up our handling of the interrupt safety of some memcg stats
"make vmalloc gfp flags usage more apparent" (Vishal Moola)
Clean up vmalloc's handling of incoming GFP flags
"mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
Teach soft dirty and userfaultfd write protect tracking to use
RISC-V's Svrsw60t59b extension
"mm: swap: small fixes and comment cleanups" (Youngjun Park)
Fix a small bug and clean up some of the swap code
"initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
Start work on converting the vma struct's flags to a bitmap, so we
stop running out of them, especially on 32-bit
"mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
Address a possible bug in the swap discard code and clean things
up a little
[ This merge also reverts commit ebb9aeb980 ("vfio/nvgrace-gpu:
register device memory for poison handling") because it looks
broken to me, I've asked for clarification - Linus ]
* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
mm: fix vma_start_write_killable() signal handling
mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
mm/swapfile: fix list iteration when next node is removed during discard
fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
mm/kfence: add reboot notifier to disable KFENCE on shutdown
memcg: remove inc/dec_lruvec_kmem_state helpers
selftests/mm/uffd: initialize char variable to Null
mm: fix DEBUG_RODATA_TEST indentation in Kconfig
mm: introduce VMA flags bitmap type
tools/testing/vma: eliminate dependency on vma->__vm_flags
mm: simplify and rename mm flags function for clarity
mm: declare VMA flags by bit
zram: fix a spelling mistake
mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
pagemap: update BUDDY flag documentation
mm: swap: remove scan_swap_map_slots() references from comments
mm: swap: change swap_alloc_slow() to void
mm, swap: remove redundant comment for read_swap_cache_async
mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
...
Stackprotector support was previously unavailable on s390 because by
default compilers generate code which is not suitable for the kernel:
the canary value is accessed via thread local storage, where the address
of thread local storage is within access registers 0 and 1.
Using those registers also for the kernel would come with a significant
performance impact and more complicated kernel entry/exit code, since
access registers contents would have to be exchanged on every kernel entry
and exit.
With the upcoming gcc 16 release new compiler options will become available
which allow to generate code suitable for the kernel. [1]
Compiler option -mstack-protector-guard=global instructs gcc to generate
stackprotector code that refers to a global stackprotector canary value via
symbol __stack_chk_guard. Access to this value is guaranteed to occur via
larl and lgrl instructions.
Furthermore, compiler option -mstack-protector-guard-record generates a
section containing all code addresses that reference the canary value.
To allow for per task canary values the instructions which load the address
of __stack_chk_guard are patched so they access a lowcore field instead: a
per task canary value is available within the task_struct of each task, and
is written to the per-cpu lowcore location on each context switch.
Also add sanity checks and debugging option to be consistent with other
kernel code patching mechanisms.
Full debugging output can be enabled with the following kernel command line
options:
debug_stackprotector
bootdebug
ignore_loglevel
earlyprintk
dyndbg="file stackprotector.c +p"
Example debug output:
stackprot: 0000021e402d4eda: c010005a9ae3 -> c01f00070240
where "<insn address>: <old insn> -> <new insn>".
[1] gcc commit 0cd1f03939d5 ("s390: Support global stack protector")
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
There shouldn't be any 31 bit code around anymore that matters.
Remove the compat layer support required to run 31 bit code.
Reason for removal is code simplification and reduced test effort.
Note that this comes without any deprecation warnings added to config
options, or kernel messages, since most likely those would be ignored
anyway.
If it turns out there is still a reason to keep the compat layer this
can be reverted at any time in the future.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Use a standard "_t" suffix for psw_t32 and rename it to psw32_t.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
INVALID_PHYS_ADDR has very similar definitions across the code base.
Hence just move that inside header <liux/mm.h> for more generic usage.
Also drop the now redundant ones which are no longer required.
Link: https://lkml.kernel.org/r/20251021025638.2420216-1-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> [s390]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
- Refactor SCLP memory hotplug code
- Introduce common boot_panic() decompressor helper macro and
use it to get rid of nearly few identical implementations
- Take into account additional key generation flags and forward
it to the ep11 implementation. With that allow users to modify
the key generation process, e.g. provide valid combinations of
XCP_BLOB_* flags
- Replace kmalloc() + copy_from_user() with memdup_user_nul()
in s390 debug facility and HMC driver
- Add DAX support for DCSS memory block devices
- Make the compiler statement attribute "assume" available with
a new __assume macro
- Rework ffs() and fls() family bitops functions, including
source code improvements and generated code optimizations.
Use the newly introduced __assume macro for that
- Enable additional network features in default configurations
- Use __GFP_ACCOUNT flag for user page table allocations to add
missing kmemcg accounting
- Add WQ_PERCPU flag to explicitly request the use of the per-CPU
workqueue for 3590 tape driver
- Switch power reading to the per-CPU and the Hiperdispatch to the
default workqueue
- Add memory allocation profiling hooks to allow better profiling
data and the /proc/allocinfo output similar to other architectures
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Merge tag 's390-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Alexander Gordeev:
- Refactor SCLP memory hotplug code
- Introduce common boot_panic() decompressor helper macro and use it to
get rid of nearly few identical implementations
- Take into account additional key generation flags and forward it to
the ep11 implementation. With that allow users to modify the key
generation process, e.g. provide valid combinations of XCP_BLOB_*
flags
- Replace kmalloc() + copy_from_user() with memdup_user_nul() in s390
debug facility and HMC driver
- Add DAX support for DCSS memory block devices
- Make the compiler statement attribute "assume" available with a new
__assume macro
- Rework ffs() and fls() family bitops functions, including source code
improvements and generated code optimizations. Use the newly
introduced __assume macro for that
- Enable additional network features in default configurations
- Use __GFP_ACCOUNT flag for user page table allocations to add missing
kmemcg accounting
- Add WQ_PERCPU flag to explicitly request the use of the per-CPU
workqueue for 3590 tape driver
- Switch power reading to the per-CPU and the Hiperdispatch to the
default workqueue
- Add memory allocation profiling hooks to allow better profiling data
and the /proc/allocinfo output similar to other architectures
* tag 's390-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (21 commits)
s390/mm: Add memory allocation profiling hooks
s390: Replace use of system_wq with system_dfl_wq
s390/diag324: Replace use of system_wq with system_percpu_wq
s390/tape: Add WQ_PERCPU to alloc_workqueue users
s390/bitops: Switch to generic ffs() if supported by compiler
s390/bitops: Switch to generic fls(), fls64(), etc.
s390/mm: Use __GFP_ACCOUNT for user page table allocations
s390/configs: Enable additional network features
s390/bitops: Cleanup __flogr()
s390/bitops: Use __assume() for __flogr() inline assembly return value
compiler_types: Add __assume macro
s390/bitops: Limit return value range of __flogr()
s390/dcssblk: Add DAX support
s390/hmcdrv: Replace kmalloc() + copy_from_user() with memdup_user_nul()
s390/debug: Replace kmalloc() + copy_from_user() with memdup_user_nul()
s390/pkey: Forward keygenflags to ep11_unwrapkey
s390/boot: Add common boot_panic() code
s390/bitops: Optimize inlining
s390/bitops: Slightly optimize ffs() and fls64()
s390/sclp: Move memory hotplug code for better modularity
...
Introduce a common boot_panic() helper macro, and use it to
get rid of three more or less identical implementations.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Since the identity mapping is pinned to address zero the lowcore is always
also mapped to address zero, this happens regardless of the relocate_lowcore
command line option. If the option is specified the lowcore is mapped
twice, instead of only once.
This means that NULL pointer accesses will succeed instead of causing an
exception (low address protection still applies, but covers only parts).
To fix this never map the first two pages of physical memory with the
identity mapping.
Fixes: 32db401965 ("s390/mm: Pin identity mapping base to zero")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Introduce a global function that jumps from the decompressor to the
decompressed kernel. Put its address into svc_old_psw, from where GDB
can take it without loading decompressor symbols. It should be
available throughout the entire decompressor execution, because it's
placed there statically, and nothing in the decompressor uses the SVC
instruction.
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Link: https://lore.kernel.org/r/20250625154220.75300-2-iii@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Files in the arch/s390/boot directory reuse logic from the rest of the
kernel by including certain C and assembly files from the kernel and lib
directories. Some of these included files contain EXPORT_SYMBOL directives.
For instance, arch/s390/boot/cmdline.c includes lib/cmdline.c, which
exports the get_option() function.
This inclusion triggers genksyms processing for the files in
arch/s390/boot, which is unnecessary and slows down the build.
Additionally, when KBUILD_SYMTYPES=1 is set, the generated symtypes data
contain exported symbols that are duplicated with the main kernel. This
duplication can confuse external kABI tools that process the symtypes data.
Address this issue by compiling the files in arch/s390/boot with
-D__DISABLE_EXPORTS.
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20250620154649.116068-1-petr.pavlu@suse.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Also indicate the name of the section where facility bits are listed,
because the manual has a length of 2124 pages. The current version is
Fourteenth Edition (May, 2022) SA22-7832-13
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: S390 ML <linux-s390@vger.kernel.org>
Signed-off-by: Xose Vazquez Perez <xose.vazquez@gmail.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20250616163248.77951-1-xose.vazquez@gmail.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
While the GCC and Clang compilers already define __ASSEMBLER__
automatically when compiling assembler code, __ASSEMBLY__ is a
macro that only gets defined by the Makefiles in the kernel.
This is bad since macros starting with two underscores are names
that are reserved by the C language. It can also be very confusing
for the developers when switching between userspace and kernelspace
coding, or when dealing with uapi headers that rather should use
__ASSEMBLER__ instead. So let's now standardize on the __ASSEMBLER__
macro that is provided by the compilers.
This is a completely mechanical patch (done with a simple "sed -i"
statement), with some manual fixups done later while rebasing the
patch.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20250611140046.137739-3-thuth@redhat.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Convert all strcpy() usages to strscpy(). strcpy() is deprecated since
it performs no bounds checking on the destination buffer.
Reviewed-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The s390 specific diag288_wdt watchdog driver makes use of the virtual
watchdog timer, which is available in most machine configurations.
If executing the diagnose instruction with subcode 0x288 results in an
exception the watchdog timer is not available, otherwise it is available.
In order to allow module autoload of the diag288_wdt module, move the
detection of the virtual watchdog timer to early boot code, and provide
its availability as a cpu feature.
This allows to make use of module_cpu_feature_match() to automatically load
the module iff the virtual watchdog timer is available.
Suggested-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Tested-by: Mete Durlu <meted@linux.ibm.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20250410095036.1525057-1-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Replace the last 2 usages of strncpy() in s390 code with strscpy().
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Add a simple sized_strscpy() implementation to allow the use of strscpy()
in the decompressor.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Use asm_inline for all inline assemblies which make use of the EX_TABLE or
ALTERNATIVE macros.
These macros expand to many lines and the compiler assumes the number of
lines within an inline assembly is the same as the number of instructions
within an inline assembly. This has an effect on inlining and loop
unrolling decisions.
In order to avoid incorrect assumptions use asm_inline, which tells the
compiler that an inline assembly has the smallest possible size.
In order to avoid confusion when asm_inline should be used or not, since a
couple of inline assemblies are quite large: the rule is to always use
asm_inline whenever the EX_TABLE or ALTERNATIVE macro is used. In specific
cases there may be reasons to not follow this guideline, but that should
be documented with the corresponding code.
Using the inline qualifier everywhere has only a small effect on the kernel
image size:
add/remove: 0/10 grow/shrink: 19/8 up/down: 1492/-1858 (-366)
The only location where this seems to matter is load_unaligned_zeropad()
from word-at-a-time.h where the compiler inlines more functions within the
dcache code, which is indeed code where performance matters.
Suggested-by: Juergen Christ <jchrist@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
When building with CONFIG_VMLINUX_MAP=y, a decompressor vmlinux.map file
is generated in the boot directory.
Add this file to .gitignore to ensure Git does not track it.
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Link: https://lore.kernel.org/r/F884C733016D6715+20250311030824.675683-1-wangyuli@uniontech.com
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Shorten __diag308() and use regular EX_TABLE program check handling.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Shorten detect_diag9c() and use regular EX_TABLE program check handling.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Shorten diag500_storage_limit() and use regular EX_TABLE program check
handling.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Shorten tprot() and use regular EX_TABLE program check handling.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Shorten __diag260() and use regular EX_TABLE program check handling.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Shorten cmma_test_essa() and use regular EX_TABLE program check handling.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The early boot code contains various open-coded inline assemblies with
exception handling. In order to handle possible exceptions each of them
changes the program check new psw, and restores it.
In order to simplify the various inline assemblies add simple exception
table support: the program check handler is called with a fully populated
pt_regs on the stack and may change the psw and register members. When the
program check handler returns the psw and registers from pt_regs will be
used to continue execution.
The program check handler searches the exception table for an entry which
matches the address of the program check. If such an entry is found the psw
address within pt_regs on the stack is replaced with a fixup address, and
execution continues at the new address.
If no entry is found the psw is changed to a disabled wait psw and
execution stops.
Before entering the C part of the program check handler the address of the
program check new psw is replaced to a minimalistic handler.
This is supposed to help against program check loops. If an exception
happens while in program check processing the register contents of the
original exception are restored and a disabled wait psw is loaded.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Setup a pt_regs structure on the stack, poplulate it in low level assembler
code, and pass it to print_pgm_check_info(). This way there is no need to
access then lowcore from print_pgm_check_info() anymore, and the function
looks like a normal program check handler function.
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Similar to x86 and loongarch add a "debug-alternative" command line
parameter, which allows for alternative debugging. The parameter
itself comes with architecture specific semantics:
"debug-alternative"
-> print debug message for every single alternative
"debug-alternative=0;2"
-> print debug message for all alternatives with type 0 and 2
"debug-alternative=0:0-7"
-> print debug message for all alternatives with type 0 which have a
facility number within the range of 0-7
"debug-alternative=0:!8;1"
-> print debug message for all alternatives with type 0, for all
facility numbers, except facility 8, and in addition print all
alternatives with type 1
A defconfig build currently results in a kernel with more than 20.000
alternatives, where the majority is for the niai alternative (spinlocks),
and the relocated lowcore alternative. The following kernel command like
options limit alternative debug output, and enable dynamic debug messages:
debug-alternative=0:!49;1:!0
earlyprintk
bootdebug
ignore_loglevel
loglevel=8
dyndbg="file alternative.c +p"
This results in output like this:
alt: [0/ 11] 0000021b9ce8680c: c0f400000089 -> c00400000000
alt: [0/ 64] 0000021b9ce87e60: c0f400000043 -> c00400000000
alt: [0/133] 0000021b9ce88c56: c0f400000027 -> c00400000000
alt: [0/ 74] 0000021b9ce89410: c0f40000002a -> c00400000000
alt: [0/ 40] 0000021b9dc3720a: 47000000 -> b280d398
alt: [0/193] 0000021b9dc37306: 47000000 -> b201d2b0
alt: [0/193] 0000021b9dc37354: c00400000000 -> d20720c0d2b0
alt: [1/ 5] 0000038d720d7bf2: c0f400000016 -> c00400000000
With
[<alternative type>/<alternative data>] <address> oldcode -> newcode
Alternative data depends on the alternative type: for type 0
(ALT_TYPE_FACILITY) data is the facility. For type 1 (ALT_TYPE_FEATURE)
data is the corresponding machine feature.
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Instead of having a private cpu_has_vx() implementation use the new common
cpu feature method. Move the facility detection to the decompressor so it
matches all other cpu features.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Move machine type detection to the decompressor and use static branches
to implement and use machine_is_[lpar|vm|kvm]() instead of a runtime check
via MACHINE_IS_[LPAR|VM|KVM].
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Use static branch(es) to implement and use machine_has_diag9c() instead of
a runtime check via MACHINE_HAS_DIAG9C.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Use static branch(es) to implement and use machine_has_tx() instead of
a runtime check with MACHINE_HAS_TE.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Use static branch(es) to implement and use machine_has_tlb_guest()
instead of a runtime check via MACHINE_HAS_TLB_GUEST.
Also add sclp_early_detect_machine_features() in order to allow for
feature detection from the decompressor.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Use static branch(es) to implement and use machine_has_scc() instead
of a runtime check via MACHINE_HAS_SCC.
This comes with a cleanup of early time initialization: the initial
tod_clock_base value is now passed via the bootdata mechanism, instead
of using absolute lowcore as transport vehicle from the decompressor
to the kernel.
Also the early tod clock initialization is moved to the decompressor
which allows to use a static branch with machine_has_scc() within the
kernel.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Convert the explicit relocated lowcore alternative type to a more
generic machine feature. This only reduces the number of alternative
types, but has no impact on code generation.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead
of testing the machine_flags lowcore member if the feature is present.
test_facility() generates better code since it results in a static branch
without accessing memory. The branch is patched via alternatives by the
decompressor depending on the availability of the required facility.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead
of testing the machine_flags lowcore member if the feature is present.
test_facility() generates better code since it results in a static branch
without accessing memory. The branch is patched via alternatives by the
decompressor depending on the availability of the required facility.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Convert MACHINE_HAS_... to cpu_has_...() which uses test_facility() instead
of testing the machine_flags lowcore member if the feature is present.
test_facility() generates better code since it results in a static branch
without accessing memory. The branch is patched via alternatives by the
decompressor depending on the availability of the required facility.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
- The rework that uncoupled physical and virtual address spaces
inadvertently prevented KASAN shadow mappings from using large
pages. Restore large page mappings for KASAN shadows
- Add decompressor routine physmem_alloc() that may fail,
unlike physmem_alloc_or_die(). This allows callers to
implement fallback paths
- Allow falling back from large pages to smaller pages (1MB or
4KB) if the allocation of 2GB pages in the decompressor can
not be fulfilled
- Add to the decompressor boot print support of "%%" format
string, width and padding hadnling, length modifiers and
decimal conversion specifiers
- Add to the decompressor message severity levels similar to
kernel ones. Support command-line options that control
console output verbosity
- Replaces boot_printk() calls with appropriate loglevel-
specific helpers such as boot_emerg(), boot_warn(), and
boot_debug().
- Collect all boot messages into a ring buffer independent
of the current log level. This is particularly useful for
early crash analysis
- If 'earlyprintk' command line parameter is not specified, store
decompressor boot messages in a ring buffer to be printed later
by the kernel, once the console driver is registered
- Add 'bootdebug' command line parameter to enable printing of
decompressor debug messages when needed. That parameters allows
message supressing and filtering
- Dump boot messages on a decompressor crash, but only if
'bootdebug' command line parameter is enabled
- When CONFIG_PRINTK_TIME is enabled, add timestamps to boot
messages in the same format as regular printk()
- Dump physical memory tracking information on boot:
online ranges, reserved areas and vmem allocations
- Dump virtual memory layout and randomization details
- Improve decompression error reporting and dump the message
ring buffer in case the boot failed and system halted
- Add an exception handler which handles exceptions when FPU
control register is attempted to be set to an invalid value.
Remove '.fixup' section as result of this change
- Use 'A', 'O', and 'R' inline assembly format flags, which
allows recent Clang compilers to generate better FPU code
- Rework uaccess code so it reads better and generates more
efficient code
- Cleanup futex inline assembly code
- Disable KMSAN instrumention for futex inline assemblies, which
contain dereferenced user pointers. Otherwise, shadows for the
user pointers would be accessed
- PFs which are not initially configured but in standby create
only a single-function PCI domain. If they are configured later
on, sibling PFs and their child VFs will not be added to their
PCI domain breaking SR-IOV expectations. Fix that by allowing
initially configured but in standby PFs create multi-function
PCI domains
- Add '-std=gnu11' to decompressor and purgatory CFLAGS to avoid
compile errors caused by kernel's own definitions of 'bool',
'false', and 'true' conflicting with the C23 reserved keywords
- Fix sclp subsystem failure when a sclp console is not present
- Fix misuse of non-NULL terminated strings in vmlogrdr driver
- Various other small improvements, cleanups and fixes
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Merge tag 's390-6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull more s390 updates from Alexander Gordeev:
- The rework that uncoupled physical and virtual address spaces
inadvertently prevented KASAN shadow mappings from using large pages.
Restore large page mappings for KASAN shadows
- Add decompressor routine physmem_alloc() that may fail, unlike
physmem_alloc_or_die(). This allows callers to implement fallback
paths
- Allow falling back from large pages to smaller pages (1MB or 4KB) if
the allocation of 2GB pages in the decompressor can not be fulfilled
- Add to the decompressor boot print support of "%%" format string,
width and padding hadnling, length modifiers and decimal conversion
specifiers
- Add to the decompressor message severity levels similar to kernel
ones. Support command-line options that control console output
verbosity
- Replaces boot_printk() calls with appropriate loglevel- specific
helpers such as boot_emerg(), boot_warn(), and boot_debug().
- Collect all boot messages into a ring buffer independent of the
current log level. This is particularly useful for early crash
analysis
- If 'earlyprintk' command line parameter is not specified, store
decompressor boot messages in a ring buffer to be printed later by
the kernel, once the console driver is registered
- Add 'bootdebug' command line parameter to enable printing of
decompressor debug messages when needed. That parameters allows
message suppressing and filtering
- Dump boot messages on a decompressor crash, but only if 'bootdebug'
command line parameter is enabled
- When CONFIG_PRINTK_TIME is enabled, add timestamps to boot messages
in the same format as regular printk()
- Dump physical memory tracking information on boot: online ranges,
reserved areas and vmem allocations
- Dump virtual memory layout and randomization details
- Improve decompression error reporting and dump the message ring
buffer in case the boot failed and system halted
- Add an exception handler which handles exceptions when FPU control
register is attempted to be set to an invalid value. Remove '.fixup'
section as result of this change
- Use 'A', 'O', and 'R' inline assembly format flags, which allows
recent Clang compilers to generate better FPU code
- Rework uaccess code so it reads better and generates more efficient
code
- Cleanup futex inline assembly code
- Disable KMSAN instrumention for futex inline assemblies, which
contain dereferenced user pointers. Otherwise, shadows for the user
pointers would be accessed
- PFs which are not initially configured but in standby create only a
single-function PCI domain. If they are configured later on, sibling
PFs and their child VFs will not be added to their PCI domain
breaking SR-IOV expectations.
Fix that by allowing initially configured but in standby PFs create
multi-function PCI domains
- Add '-std=gnu11' to decompressor and purgatory CFLAGS to avoid
compile errors caused by kernel's own definitions of 'bool', 'false',
and 'true' conflicting with the C23 reserved keywords
- Fix sclp subsystem failure when a sclp console is not present
- Fix misuse of non-NULL terminated strings in vmlogrdr driver
- Various other small improvements, cleanups and fixes
* tag 's390-6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (53 commits)
s390/vmlogrdr: Use array instead of string initializer
s390/vmlogrdr: Use internal_name for error messages
s390/sclp: Initialize sclp subsystem via arch_cpu_finalize_init()
s390/tools: Use array instead of string initializer
s390/vmem: Fix null-pointer-arithmetic warning in vmem_map_init()
s390: Add '-std=gnu11' to decompressor and purgatory CFLAGS
s390/bitops: Use correct constraint for arch_test_bit() inline assembly
s390/pci: Fix SR-IOV for PFs initially in standby
s390/futex: Avoid KMSAN instrumention for user pointers
s390/uaccess: Rename get_put_user_noinstr_attributes to uaccess_kmsan_or_inline
s390/futex: Cleanup futex_atomic_cmpxchg_inatomic()
s390/futex: Generate futex atomic op functions
s390/uaccess: Remove INLINE_COPY_FROM_USER and INLINE_COPY_TO_USER
s390/uaccess: Use asm goto for put_user()/get_user()
s390/uaccess: Remove usage of the oac specifier
s390/uaccess: Replace EX_TABLE_UA_LOAD_MEM exception handling
s390/uaccess: Cleanup noinstr __put_user()/__get_user() inline assembly constraints
s390/uaccess: Remove __put_user_fn()/__get_user_fn() wrappers
s390/uaccess: Move put_user() / __put_user() close to put_user() asm code
s390/uaccess: Use asm goto for __mvc_kernel_nofault()
...
Use a zero identity base when CONFIG_RANDOMIZE_IDENTITY_BASE is off,
slightly optimizing __pa/__va calculations.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Currently, decompression error messages can be very uninformative:
[ 0.029853] startup: read error
[ 0.040507] startup: -- System halted
Improve these messages to make it clear that the error originates from
the decompression code. Additionally, on decompression failures, if
bootdebug is enabled, dump the message ring buffer before halting. This
provides more context for diagnosing startup issues.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Add boot_debug() calls to log various memory layout decisions and
randomization details during early startup, improving debugging
capabilities.
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
