Use the more precise CONFIG_CC_HAS_ASM_AOR_FORMAT_FLAGS to tell if the
compiler has support for the A, O, and R inline assembly format flags.
This allows recent Clang compilers to generate better code.
Move code around so the good (aka better) case at the top of each ifdef
construct.
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 CC_HAS_ASM_AOR_FORMAT_FLAGS Kconfig option. Use this option for
inline assemblies where the A, O, or R format flags are used.
Those flags are not available for Clang versions before 19.1.0.
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>
Config options which can be used to check for compiler bugs and features
have the compiler independent CC prefix in order to avoid duplicating and
having to check config options for multiple compilers. Therefore rename the
config option accordingly.
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>
The fixup section was added again by mistake when test_fp_ctl() was
removed. The reason for the removal of the fixup section is described in
commit 484a8ed8b7 ("s390/extable: add dedicated uaccess handler").
Remove it again for the same reason.
Add an exception handler which handles exceptions when the floating point
control register is attempted to be set to invalid values. The exception
handler sets the floating point control register to zero and continues
execution at the specified address.
The new sfpc inline assembly is open-coded to make back porting a bit
easier.
Fixes: 702644249d ("s390/fpu: get rid of test_fp_ctl()")
Cc: stable@vger.kernel.org
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>
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>
Reorder the store_ipl_parmblock(), uv_query_info(), and command line
setup calls to occur earlier. This ensures debug printing covers all
memory tracking activities from the start.
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>
Introduce boot_debug() calls to track memory detection, online ranges,
reserved areas, and allocations (except for VMEM allocations, which are
too frequent). Instead introduce dump_physmem_reserved() function which
prints out full memory tracking information. This helps in debugging
early boot memory handling.
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>
sclp_early_printk() ignores boot console debug settings and prints
unconditionally. It also prints message without any timestamp
or formatting. Convert it to pr_info().
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>
When CONFIG_PRINTK_TIME is enabled, add timestamps to boot messages in
the same format as regular printk. Timestamps appear only with earlyprintk
and are stored in the boot messages ring buffer, but are not propagated
to main kernel messages (if earlyprintk is not enabled). This prevents
double timestamps in the output.
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>
Dump the boot message ring buffer when a crash occurs during boot, but
only if bootdebug is enabled. This helps assist in analyzing boot-time
issues by providing additional debugging information.
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>
Enhance boot debugging by allowing the "bootdebug" kernel parameter to
accept an optional comma-separated list of prefixes. Only debug messages
starting with these prefixes will be printed during boot. For example:
bootdebug=startup,vmem
Not specifying a filter for the "bootdebug" parameter prints all debug
messages. The `boot_fmt` macro can be defined to set a common prefix:
#define boot_fmt(fmt) "startup: " fmt
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>
Suppress decompressor debug messages by default, similar to regular
kernel debug messages that require 'DEBUG' or 'dyndbg' to be enabled
(depending on CONFIG_DYNAMIC_DEBUG). Introduce a 'bootdebug' option to
enable printing these messages when needed.
All messages are still stored in the boot ring buffer regardless.
To enable boot debug messages:
bootdebug debug
Or combine with 'earlyprintk' to print them without delay:
bootdebug debug earlyprintk
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>
When earlyprintk is not specified, boot messages are only stored in a
ring buffer to be printed later by printk when console driver is
registered.
Critical messages from boot_emerg() are always printed immediately,
even without earlyprintk.
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>
Collect all boot messages into a ring buffer independent of the current
log level. This allows to retain all boot-time messages, which is
particularly useful for analyzing early crashes.
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>
Now that boot_printk() supports decimal specifiers, update boot_emerg()
messages to use %d and %lu instead of %x and %lx where appropriate.
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>
Replaces boot_printk() calls with appropriate loglevel-specific helpers
such as boot_emerg(), boot_warn(), and boot_debug().
Using functions with explicit log levels improves log clarity and aligns
the boot code with standard kernel logging practices. This makes it
easier to filter and manage boot-time messages based on their severity.
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 message severity levels for boot messages, similar to the main
kernel. Support command-line options that control console output
verbosity, including "loglevel," "ignore_loglevel," "debug," and "quiet".
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>
Enable the boot_printk() function to print decimal values. Add the 'd',
'i', and 'u' conversion specifiers support.
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>
Enhance boot_printk() to support field width and padding across all
argument types for better formatting.
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>
For KASAN shadow mappings, switch from physmem_alloc_or_die() to
physmem_alloc() and return INVALID_PHYS_ADDR on allocation failure. This
allows gracefully falling back from large pages to smaller pages (1MB
or 4KB) if the allocation of 2GB size/aligned pages cannot be fulfilled.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Add physmem_alloc() as a variant of physmem_alloc_or_die() that can return
an error instead of triggering a panic on OOM. This allows callers to
implement alternative fallback paths.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
The new name better reflects the function's behavior, emphasizing that
it will terminate execution if allocation fails.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Commit c98d2ecae0 ("s390/mm: Uncouple physical vs virtual address
spaces") introduced a large_allowed() helper that restricts which mapping
modes can use large pages. This change unintentionally prevented KASAN
shadow mappings from using large pages, despite there being no reason
to avoid them. In fact, large pages are preferred for performance.
Since commit d8073dc6bc ("s390/mm: Allow large pages only for aligned
physical addresses"), both can_large_pud() and can_large_pmd() call _pa()
to check if large page physical addresses are aligned. However, _pa()
has a side effect: it allocates memory in POPULATE_KASAN_MAP_SHADOW
mode.
Rename large_allowed() to large_page_mapping_allowed() and add
POPULATE_KASAN_MAP_SHADOW to the allowed list to restore large page
mappings for KASAN shadows.
While large_page_mapping_allowed() isn't strictly necessary with current
mapping modes since disallowed modes either don't map anything or fail
alignment and size checks, keep it for clarity.
Rename _pa() to resolve_pa_may_alloc() for clarity and to emphasize
existing side effect. Rework can_large_pud()/can_large_pmd() to take
the side effect into consideration and actually return physical address
instead of just checking conditions.
Fixes: c98d2ecae0 ("s390/mm: Uncouple physical vs virtual address spaces")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
The maximum number of load/store watchpoints and fetch instruction
watchpoints is 14 each according to LoongArch Reference Manual, so
extend the maximum number of watchpoints from 8 to 14 for ptrace.
By the way, just simply change 8 to 14 for the definition in struct
user_watch_state at the beginning, but it may corrupt uapi, then add
a new struct user_watch_state_v2 directly.
As far as I can tell, the only users for this struct in the userspace
are GDB and LLDB, there are no any problems of software compatibility
between the application and kernel according to the analysis.
The compatibility problem has been considered while developing and
testing. When the applications in the userspace get watchpoint state,
the length will be specified which is no bigger than the sizeof struct
user_watch_state or user_watch_state_v2, the actual length is assigned
as the minimal value of the application and kernel in the generic code
of ptrace:
kernel/ptrace.c: ptrace_regset():
kiov->iov_len = min(kiov->iov_len,
(__kernel_size_t) (regset->n * regset->size));
if (req == PTRACE_GETREGSET)
return copy_regset_to_user(task, view, regset_no, 0,
kiov->iov_len, kiov->iov_base);
else
return copy_regset_from_user(task, view, regset_no, 0,
kiov->iov_len, kiov->iov_base);
For example, there are four kind of combinations, all of them work well.
(1) "older kernel + older gdb", the actual length is 8+(8+8+4+4)*8=200;
(2) "newer kernel + newer gdb", the actual length is 8+(8+8+4+4)*14=344;
(3) "older kernel + newer gdb", the actual length is 8+(8+8+4+4)*8=200;
(4) "newer kernel + older gdb", the actual length is 8+(8+8+4+4)*8=200.
Link: https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html#control-and-status-registers-related-to-watchpoints
Cc: stable@vger.kernel.org
Fixes: 1a69f7a161 ("LoongArch: ptrace: Expose hardware breakpoints to debuggers")
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
We need to switch SFB (Store Fill Buffer) and TSO (Total Store Order)
state at runtime to debug memory management and KVM virtualization, so
add two debugfs entries "sfb_state" and "tso_state" under the directory
/sys/kernel/debug/loongarch.
Query SFB:
cat /sys/kernel/debug/loongarch/sfb_state
Enable SFB:
echo 1 > /sys/kernel/debug/loongarch/sfb_state
Disable SFB:
echo 0 > /sys/kernel/debug/loongarch/sfb_state
Query TSO:
cat /sys/kernel/debug/loongarch/tso_state
Switch TSO:
echo [TSO] > /sys/kernel/debug/loongarch/tso_state
Available [TSO] states:
0 (No Load No Store) 1 (All Load No Store) 3 (Same Load No Store)
4 (No Load All Store) 5 (All Load All Store) 7 (Same Load All Store)
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
The enable_gpe_wakeup() function calls acpi_enable_all_wakeup_gpes(),
and the later one may call the preempt_schedule_common() function,
resulting in a thread switch and causing the CPU to be in an interrupt
enabled state after the enable_gpe_wakeup() function returns, leading
to the warnings as follow.
[ C0] WARNING: ... at kernel/time/timekeeping.c:845 ktime_get+0xbc/0xc8
[ C0] ...
[ C0] Call Trace:
[ C0] [<90000000002243b4>] show_stack+0x64/0x188
[ C0] [<900000000164673c>] dump_stack_lvl+0x60/0x88
[ C0] [<90000000002687e4>] __warn+0x8c/0x148
[ C0] [<90000000015e9978>] report_bug+0x1c0/0x2b0
[ C0] [<90000000016478e4>] do_bp+0x204/0x3b8
[ C0] [<90000000025b1924>] exception_handlers+0x1924/0x10000
[ C0] [<9000000000343bbc>] ktime_get+0xbc/0xc8
[ C0] [<9000000000354c08>] tick_sched_timer+0x30/0xb0
[ C0] [<90000000003408e0>] __hrtimer_run_queues+0x160/0x378
[ C0] [<9000000000341f14>] hrtimer_interrupt+0x144/0x388
[ C0] [<9000000000228348>] constant_timer_interrupt+0x38/0x48
[ C0] [<90000000002feba4>] __handle_irq_event_percpu+0x64/0x1e8
[ C0] [<90000000002fed48>] handle_irq_event_percpu+0x20/0x80
[ C0] [<9000000000306b9c>] handle_percpu_irq+0x5c/0x98
[ C0] [<90000000002fd4a0>] generic_handle_domain_irq+0x30/0x48
[ C0] [<9000000000d0c7b0>] handle_cpu_irq+0x70/0xa8
[ C0] [<9000000001646b30>] handle_loongarch_irq+0x30/0x48
[ C0] [<9000000001646bc8>] do_vint+0x80/0xe0
[ C0] [<90000000002aea1c>] finish_task_switch.isra.0+0x8c/0x2a8
[ C0] [<900000000164e34c>] __schedule+0x314/0xa48
[ C0] [<900000000164ead8>] schedule+0x58/0xf0
[ C0] [<9000000000294a2c>] worker_thread+0x224/0x498
[ C0] [<900000000029d2f0>] kthread+0xf8/0x108
[ C0] [<9000000000221f28>] ret_from_kernel_thread+0xc/0xa4
[ C0]
[ C0] ---[ end trace 0000000000000000 ]---
The root cause is acpi_enable_all_wakeup_gpes() uses a mutex to protect
acpi_hw_enable_all_wakeup_gpes(), and acpi_ut_acquire_mutex() may cause
a thread switch. Since there is no longer concurrent execution during
loongarch_acpi_suspend(), we can call acpi_hw_enable_all_wakeup_gpes()
directly in enable_gpe_wakeup().
The solution is similar to commit 22db06337f ("ACPI: sleep: Avoid
breaking S3 wakeup due to might_sleep()").
Fixes: 366bb35a8e ("LoongArch: Add suspend (ACPI S3) support")
Signed-off-by: Qunqin Zhao <zhaoqunqin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Commit 78966b550289 ("s390: pgtable: add statistics for PUD and P4D level
page table") misses the call to pagetable_p4d_ctor() against a newly
allocated P4D table in crst_table_upgrade();
Commit 68c601de75d8 ("mm: introduce ctor/dtor at PGD level") misses the
call to pagetable_pgd_ctor() against a newly allocated PGD and the call to
pagetable_dtor() against a newly allocated P4D that is about to be freed
on crst_table_upgrade() PGD upgrade fail path.
The missed constructors and destructor break (at least) the page table
accounting when a process memory space is upgraded.
Link: https://lkml.kernel.org/r/20250123160349.200154-1-agordeev@linux.ibm.com
Fixes: 78966b550289 ("s390: pgtable: add statistics for PUD and P4D level page table")
Fixes: 68c601de75d8 ("mm: introduce ctor/dtor at PGD level")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Heiko Carstens <hca@linux.ibm.com>
Closes: https://lore.kernel.org/all/20250122074954.8685-A-hca@linux.ibm.com/
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Acked-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm: update mips to use do_mmap(), make mmap_region()
internal".
Currently the only user of mmap_region() outside of the memory management
code is the MIPS VDSO implementation.
This uses mmap_region() to map a 'delay slot emulation page' at the top of
the stack which is read-only and executable.
This mapping requires that an already-acquired mmap write lock is utilised
and that uffd and populate logic is ignored. This rules out vm_mmap(),
however do_mmap() fits the bill.
Adapt this code to use do_mmap() and then once done, make mmap_region()
internal and userland testable, and avoid any other uses of mmap_region(),
which is absolutely and strictly an internal mm function which bypasses a
great number of checks and logic.
This patch (of 2):
mmap_region() is an internal memory management implementation detail that
is not intended to be used outside of the memory management subsystem.
Map the delay slot emulation page using do_mmap() which makes use of the
already-held mmap write lock and bypasses unneeded populate and
userfaultfd logic.
This should have the precise same behaviour as the existing logic.
Link: https://lkml.kernel.org/r/cover.1735819274.git.lorenzo.stoakes@oracle.com
Link: https://lkml.kernel.org/r/ef076e381570f709e5c2c142dc030ec5b3309a0e.1735819274.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Jann Horn <jannh@google.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We already have a generic implementation of alloc/free up to P4D level, as
well as pgd_free(). Let's finish the work and add a generic PGD-level
alloc helper as well.
Unlike at lower levels, almost all architectures need some specific magic
at PGD level (typically initialising PGD entries), so introducing a
generic pgd_alloc() isn't worth it. Instead we introduce two new helpers,
__pgd_alloc() and __pgd_free(), and make use of them in the arch-specific
pgd_alloc() and pgd_free() wherever possible. To accommodate as many arch
as possible, __pgd_alloc() takes a page allocation order.
Because pagetable_alloc() allocates zeroed pages, explicit zeroing in
pgd_alloc() becomes redundant and we can get rid of it. Some trivial
implementations of pgd_free() also become unnecessary once __pgd_alloc()
is used; remove them.
Another small improvement is consistent accounting of PGD pages by using
GFP_PGTABLE_{USER,KERNEL} as appropriate.
Not all PGD allocations can be handled by the generic helpers. In
particular, multiple architectures allocate PGDs from a kmem_cache, and
those PGDs may not be page-sized.
Link: https://lkml.kernel.org/r/20250103184415.2744423-6-kevin.brodsky@arm.com
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
