The interrupt core code has an ever repeating pattern:
unsigned long flags;
struct irq_desc *desc = irq_get_desc_[bus]lock(irq, &flags, mode);
if (!desc)
return -EINVAL;
....
irq_put_desc_[bus]unlock(desc, flags);
That requires gotos in failure paths and just creates visual clutter.
Provide lock guards, which allow to simplify the code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/20250429065420.061659985@linutronix.de
Add new function *_twothreecell() to extend support to parse three-cell
interrupts which encoded as <instance hwirq irqflag>, the translate
function will retrieve irq number and flag from last two cells.
This API will be used in gpio irq driver which need to work with
two or three cells cases.
Signed-off-by: Yixun Lan <dlan@gentoo.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250326-04-gpio-irq-threecell-v3-1-aab006ab0e00@gentoo.org
Pull perf event fix from Ingo Molnar:
"Fix a perf events time accounting bug"
* tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix child_total_time_enabled accounting bug at task exit
Pull scheduler fixes from Ingo Molnar:
- Fix a nonsensical Kconfig combination
- Remove an unnecessary rseq-notification
* tag 'sched-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rseq: Eliminate useless task_work on execve
sched/isolation: Make CONFIG_CPU_ISOLATION depend on CONFIG_SMP
Pull timer cleanups from Thomas Gleixner:
"A set of final cleanups for the timer subsystem:
- Convert all del_timer[_sync]() instances over to the new
timer_delete[_sync]() API and remove the legacy wrappers.
Conversion was done with coccinelle plus some manual fixups as
coccinelle chokes on scoped_guard().
- The final cleanup of the hrtimer_init() to hrtimer_setup()
conversion.
This has been delayed to the end of the merge window, so that all
patches which have been merged through other trees are in mainline
and all new users are catched.
Doing this right before rc1 ensures that new code which is merged post
rc1 is not introducing new instances of the original functionality"
* tag 'timers-cleanups-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tracing/timers: Rename the hrtimer_init event to hrtimer_setup
hrtimers: Rename debug_init_on_stack() to debug_setup_on_stack()
hrtimers: Rename debug_init() to debug_setup()
hrtimers: Rename __hrtimer_init_sleeper() to __hrtimer_setup_sleeper()
hrtimers: Remove unnecessary NULL check in hrtimer_start_range_ns()
hrtimers: Make callback function pointer private
hrtimers: Merge __hrtimer_init() into __hrtimer_setup()
hrtimers: Switch to use __htimer_setup()
hrtimers: Delete hrtimer_init()
treewide: Convert new and leftover hrtimer_init() users
treewide: Switch/rename to timer_delete[_sync]()
Pull more irq updates from Thomas Gleixner:
"A set of updates for the interrupt subsystem:
- A treewide cleanup for the irq_domain code, which makes the naming
consistent and gets rid of the original oddity of naming domains
'host'.
This is a trivial mechanical change and is done late to ensure that
all instances have been catched and new code merged post rc1 wont
reintroduce new instances.
- A trivial consistency fix in the migration code
The recent introduction of irq_force_complete_move() in the core
code, causes a problem for the nostalgia crowd who maintains ia64
out of tree.
The code assumes that hierarchical interrupt domains are enabled
and dereferences irq_data::parent_data unconditionally. That works
in mainline because both architectures which enable that code have
hierarchical domains enabled. Though it breaks the ia64 build,
which enables the functionality, but does not have hierarchical
domains.
While it's not really a problem for mainline today, this
unconditional dereference is inconsistent and trivially fixable by
using the existing helper function irqd_get_parent_data(), which
has the appropriate #ifdeffery in place"
* tag 'irq-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/migration: Use irqd_get_parent_data() in irq_force_complete_move()
irqdomain: Stop using 'host' for domain
irqdomain: Rename irq_get_default_host() to irq_get_default_domain()
irqdomain: Rename irq_set_default_host() to irq_set_default_domain()
Pull timer fix from Thomas Gleixner:
"A revert to fix a adjtimex() regression:
The recent change to prevent that time goes backwards for the coarse
time getters due to immediate multiplier adjustments via adjtimex(),
changed the way how the timekeeping core treats that.
That change result in a regression on the adjtimex() side, which is
user space visible:
1) The forwarding of the base time moves the update out of the
original period and establishes a new one. That's changing the
behaviour of the [PF]LL control, which user space expects to be
applied periodically.
2) The clearing of the accumulated NTP error due to #1, changes the
behaviour as well.
An attempt to delay the multiplier/frequency update to the next tick
did not solve the problem as userspace expects that the multiplier or
frequency updates are in effect, when the syscall returns.
There is a different solution for the coarse time problem available,
so revert the offending commit to restore the existing adjtimex()
behaviour"
* tag 'timers-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "timekeeping: Fix possible inconsistencies in _COARSE clockids"
Pull Kbuild updates from Masahiro Yamada:
- Improve performance in gendwarfksyms
- Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS
- Support CONFIG_HEADERS_INSTALL for ARCH=um
- Use more relative paths to sources files for better reproducibility
- Support the loong64 Debian architecture
- Add Kbuild bash completion
- Introduce intermediate vmlinux.unstripped for architectures that need
static relocations to be stripped from the final vmlinux
- Fix versioning in Debian packages for -rc releases
- Treat missing MODULE_DESCRIPTION() as an error
- Convert Nios2 Makefiles to use the generic rule for built-in DTB
- Add debuginfo support to the RPM package
* tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
kbuild: rpm-pkg: build a debuginfo RPM
kconfig: merge_config: use an empty file as initfile
nios2: migrate to the generic rule for built-in DTB
rust: kbuild: skip `--remap-path-prefix` for `rustdoc`
kbuild: pacman-pkg: hardcode module installation path
kbuild: deb-pkg: don't set KBUILD_BUILD_VERSION unconditionally
modpost: require a MODULE_DESCRIPTION()
kbuild: make all file references relative to source root
x86: drop unnecessary prefix map configuration
kbuild: deb-pkg: add comment about future removal of KDEB_COMPRESS
kbuild: Add a help message for "headers"
kbuild: deb-pkg: remove "version" variable in mkdebian
kbuild: deb-pkg: fix versioning for -rc releases
Documentation/kbuild: Fix indentation in modules.rst example
x86: Get rid of Makefile.postlink
kbuild: Create intermediate vmlinux build with relocations preserved
kbuild: Introduce Kconfig symbol for linking vmlinux with relocations
kbuild: link-vmlinux.sh: Make output file name configurable
kbuild: do not generate .tmp_vmlinux*.map when CONFIG_VMLINUX_MAP=y
Revert "kheaders: Ignore silly-rename files"
...
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.
Conversion was done with coccinelle plus manual fixups where necessary.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This reverts commit 757b000f7b.
Miroslav reported that the changes for handling the inconsistencies in the
coarse time getters result in a regression on the adjtimex() side.
There are two issues:
1) The forwarding of the base time moves the update out of the original
period and establishes a new one.
2) The clearing of the accumulated NTP error is changing the behaviour as
well.
Userspace expects that multiplier/frequency updates are in effect, when the
syscall returns, so delaying the update to the next tick is not solving the
problem either.
Revert the change, so that the established expectations of user space
implementations (ntpd, chronyd) are restored. The re-introduced
inconsistency of the coarse time getters will be addressed in a subsequent
fix.
Fixes: 757b000f7b ("timekeeping: Fix possible inconsistencies in _COARSE clockids")
Reported-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/Z-qsg6iDGlcIJulJ@localhost
Frank reported, that the common irq_force_complete_move() breaks the out of
tree build of ia64. The reason is that ia64 uses the migration code, but
does not have hierarchical interrupt domains enabled.
This went unnoticed in mainline as both x86 and RISC-V have hierarchical
domains enabled. Not that it matters for mainline, but it's still
inconsistent.
Use irqd_get_parent_data() instead of accessing the parent_data field
directly. The helper returns NULL when hierarchical domains are disabled
otherwise it accesses the parent_data field of the domain.
No functional change.
Fixes: 751dc837da ("genirq: Introduce common irq_force_complete_move() implementation")
Reported-by: Frank Scheiner <frank.scheiner@web.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Frank Scheiner <frank.scheiner@web.de>
Link: https://lore.kernel.org/all/87h634ugig.ffs@tglx
Pull ring-buffer updates from Steven Rostedt:
"Persistent buffer cleanups and simplifications.
It was mistaken that the physical memory returned from "reserve_mem"
had to be vmap()'d to get to it from a virtual address. But
reserve_mem already maps the memory to the virtual address of the
kernel so a simple phys_to_virt() can be used to get to the virtual
address from the physical memory returned by "reserve_mem". With this
new found knowledge, the code can be cleaned up and simplified.
- Enforce that the persistent memory is page aligned
As the buffers using the persistent memory are all going to be
mapped via pages, make sure that the memory given to the tracing
infrastructure is page aligned. If it is not, it will print a
warning and fail to map the buffer.
- Use phys_to_virt() to get the virtual address from reserve_mem
Instead of calling vmap() on the physical memory returned from
"reserve_mem", use phys_to_virt() instead.
As the memory returned by "memmap" or any other means where a
physical address is given to the tracing infrastructure, it still
needs to be vmap(). Since this memory can never be returned back to
the buddy allocator nor should it ever be memmory mapped to user
space, flag this buffer and up the ref count. The ref count will
keep it from ever being freed, and the flag will prevent it from
ever being memory mapped to user space.
- Use vmap_page_range() for memmap virtual address mapping
For the memmap buffer, instead of allocating an array of struct
pages, assigning them to the contiguous phsycial memory and then
passing that to vmap(), use vmap_page_range() instead
- Replace flush_dcache_folio() with flush_kernel_vmap_range()
Instead of calling virt_to_folio() and passing that to
flush_dcache_folio(), just call flush_kernel_vmap_range() directly.
This also fixes a bug where if a subbuffer was bigger than
PAGE_SIZE only the PAGE_SIZE portion would be flushed"
* tag 'trace-ringbuffer-v6.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Use flush_kernel_vmap_range() over flush_dcache_folio()
tracing: Use vmap_page_range() to map memmap ring buffer
tracing: Have reserve_mem use phys_to_virt() and separate from memmap buffer
tracing: Enforce the persistent ring buffer to be page aligned
Pull more MM updates from Andrew Morton:
- The series "mm: fixes for fallouts from mem_init() cleanup" from Mike
Rapoport fixes a couple of issues with the just-merged "arch, mm:
reduce code duplication in mem_init()" series
- The series "MAINTAINERS: add my isub-entries to MM part." from Mike
Rapoport does some maintenance on MAINTAINERS
- The series "remove tlb_remove_page_ptdesc()" from Qi Zheng does some
cleanup work to the page mapping code
- The series "mseal system mappings" from Jeff Xu permits sealing of
"system mappings", such as vdso, vvar, vvar_vclock, vectors (arm
compat-mode), sigpage (arm compat-mode)
- Plus the usual shower of singleton patches
* tag 'mm-stable-2025-04-02-22-07' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (31 commits)
mseal sysmap: add arch-support txt
mseal sysmap: enable s390
selftest: test system mappings are sealed
mseal sysmap: update mseal.rst
mseal sysmap: uprobe mapping
mseal sysmap: enable arm64
mseal sysmap: enable x86-64
mseal sysmap: generic vdso vvar mapping
selftests: x86: test_mremap_vdso: skip if vdso is msealed
mseal sysmap: kernel config and header change
mm: pgtable: remove tlb_remove_page_ptdesc()
x86: pgtable: convert to use tlb_remove_ptdesc()
riscv: pgtable: unconditionally use tlb_remove_ptdesc()
mm: pgtable: convert some architectures to use tlb_remove_ptdesc()
mm: pgtable: change pt parameter of tlb_remove_ptdesc() to struct ptdesc*
mm: pgtable: make generic tlb_remove_table() use struct ptdesc
microblaze/mm: put mm_cmdline_setup() in .init.text section
mm/memory_hotplug: fix call folio_test_large with tail page in do_migrate_range
MAINTAINERS: mm: add entry for secretmem
MAINTAINERS: mm: add entry for numa memblocks and numa emulation
...
Pull sched_ext fixes from Tejun Heo:
- Calling scx_bpf_create_dsq() with the same ID would succeed creating
duplicate DSQs. Fix it to return -EEXIST.
- scx_select_cpu_dfl() fixes and cleanups.
- Synchronize tool/sched_ext with external scheduler repo. While this
isn't a fix. There's no risk to the kernel and it's better if they
stay synced closer.
* tag 'sched_ext-for-6.15-rc0-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext:
tools/sched_ext: Sync with scx repo
sched_ext: initialize built-in idle state before ops.init()
sched_ext: create_dsq: Return -EEXIST on duplicate request
sched_ext: Remove a meaningless conditional goto in scx_select_cpu_dfl()
sched_ext: idle: Fix return code of scx_select_cpu_dfl()
Pull tracing fixes from Steven Rostedt:
- Fix build error when CONFIG_PROBE_EVENTS_BTF_ARGS is not enabled
The tracing of arguments in the function tracer depends on some
functions that are only defined when PROBE_EVENTS_BTF_ARGS is
enabled. In fact, PROBE_EVENTS_BTF_ARGS also depends on all the same
configs as the function argument tracing requires. Just have the
function argument tracing depend on PROBE_EVENTS_BTF_ARGS.
- Free module_delta for persistent ring buffer instance
When an instance holds the persistent ring buffer, it allocates a
helper array to hold the deltas between where modules are loaded on
the last boot and the current boot. This array needs to be freed when
the instance is freed.
- Add cond_resched() to loop in ftrace_graph_set_hash()
The hash functions in ftrace loop over every function that can be
enabled by ftrace. This can be 50,000 functions or more. This loop is
known to trigger soft lockup warnings and requires a cond_resched().
The loop in ftrace_graph_set_hash() was missing it.
- Fix the event format verifier to include "%*p.." arguments
To prevent events from dereferencing stale pointers that can happen
if a trace event uses a dereferece pointer to something that was not
copied into the ring buffer and can be freed by the time the trace is
read, a verifier is called. At boot or module load, the verifier
scans the print format string for pointers that can be dereferenced
and it checks the arguments to make sure they do not contain
something that can be freed. The "%*p" was not handled, which would
add another argument and cause the verifier to not only not verify
this pointer, but it will look at the wrong argument for every
pointer after that.
- Fix mcount sorttable building for different endian type target
When modifying the ELF file to sort the mcount_loc table in the
sorttable.c code, the endianess of the file and the host is used to
determine if the bytes need to be swapped when calculations are done.
A change was made to the sorting of the mcount_loc that read the
values from the ELF file into an array and the swap happened on the
filling of the array. But one of the calculations of the array still
did the swap when it did not need to. This caused building on a
little endian machine for a big endian target to not find the mcount
function in the 'nm' table and it zeroed it out, causing there to be
no functions available to trace.
- Add goto out_unlock jump to rv_register_monitor() on error path
One of the error paths in rv_register_monitor() just returned the
error when it should have jumped to the out_unlock label to release
the mutex.
* tag 'trace-v6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
rv: Fix missing unlock on double nested monitors return path
scripts/sorttable: Fix endianness handling in build-time mcount sort
tracing: Verify event formats that have "%*p.."
ftrace: Add cond_resched() to ftrace_graph_set_hash()
tracing: Free module_delta on freeing of persistent ring buffer
ftrace: Have tracing function args depend on PROBE_EVENTS_BTF_ARGS
Eliminate a useless task_work on execve by moving the call to
rseq_set_notify_resume() from sched_mm_cid_after_execve() to the error
path of bprm_execve().
The call to rseq_set_notify_resume() from sched_mm_cid_after_execve() is
pointless in the success case, because rseq_execve() will clear the rseq
pointer before returning to userspace.
sched_mm_cid_after_execve() is called from both the success and error
paths of bprm_execve(). The call to rseq_set_notify_resume() is needed
on error because the mm_cid may have changed.
Also move the rseq_execve() to right after sched_mm_cid_after_execve()
in bprm_execve().
[ mingo: Merged to a recent upstream kernel, extended the changelog. ]
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20250327132945.1558783-1-mathieu.desnoyers@efficios.com
Pull tty/serial driver updates from Greg KH:
"Here is the big set of serial and tty driver updates for 6.15-rc1.
Include in here are the following:
- more great tty layer cleanups from Jiri. Someday this will be done,
but that's not going to be any year soon...
- kdb debug driver reverts to fix a reported issue
- lots of .dts binding updates for different devices with serial
devices
- lots of tiny updates and tweaks and a few bugfixes for different
serial drivers.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (79 commits)
tty: serial: fsl_lpuart: Fix unused variable 'sport' build warning
serial: stm32: do not deassert RS485 RTS GPIO prematurely
serial: 8250: add driver for NI UARTs
dt-bindings: serial: snps-dw-apb-uart: document RZ/N1 binding without DMA
serial: icom: fix code format problems
serial: sh-sci: Save and restore more registers
tty: serial: pl011: remove incorrect of_match_ptr annotation
dt-bindings: serial: snps-dw-apb-uart: Add support for rk3562
tty: serial: lpuart: only disable CTS instead of overwriting the whole UARTMODIR register
tty: caif: removed unused function debugfs_tx()
serial: 8250_dma: terminate correct DMA in tx_dma_flush()
tty: serial: fsl_lpuart: rename register variables more specifically
tty: serial: fsl_lpuart: use port struct directly to simply code
tty: serial: fsl_lpuart: Use u32 and u8 for register variables
tty: serial: fsl_lpuart: disable transmitter before changing RS485 related registers
tty: serial: 8250: Add Brainboxes XC devices
dt-bindings: serial: fsl-lpuart: support i.MX94
tty: serial: 8250: Add some more device IDs
dt-bindings: serial: samsung: add exynos7870-uart compatible
serial: 8250_dw: Comment possible corner cases in serial_out() implementation
...
Pull vfs fixes from Christian Brauner:
- Add a new maintainer for configfs
- Fix exportfs module description
- Place flexible array memeber at the end of an internal struct in the
mount code
- Add new maintainer for netfslib as Jeff Layton is stepping down as
current co-maintainer
- Fix error handling in cachefiles_get_directory()
- Cleanup do_notify_pidfd()
- Fix syscall number definitions in pidfd selftests
- Fix racy usage of fs_struct->in exec during multi-threaded exec
- Ensure correct exit code is reported when pidfs_exit() is called from
release_task() for a delayed thread-group leader exit
- Fix conflicting iomap flag definitions
* tag 'vfs-6.15-rc1.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
iomap: Fix conflicting values of iomap flags
fs: namespace: Avoid -Wflex-array-member-not-at-end warning
MAINTAINERS: configfs: add Andreas Hindborg as maintainer
exportfs: add module description
exit: fix the usage of delay_group_leader->exit_code in do_notify_parent() and pidfs_exit()
netfs: add Paulo as maintainer and remove myself as Reviewer
cachefiles: Fix oops in vfs_mkdir from cachefiles_get_directory
exec: fix the racy usage of fs_struct->in_exec
selftests/pidfd: fixes syscall number defines
pidfs: cleanup the usage of do_notify_pidfd()
Pull objtool fixes from Ingo Molnar:
"These are objtool fixes and updates by Josh Poimboeuf, centered around
the fallout from the new CONFIG_OBJTOOL_WERROR=y feature, which,
despite its default-off nature, increased the profile/impact of
objtool warnings:
- Improve error handling and the presentation of warnings/errors
- Revert the new summary warning line that some test-bot tools
interpreted as new regressions
- Fix a number of objtool warnings in various drivers, core kernel
code and architecture code. About half of them are potential
problems related to out-of-bounds accesses or potential undefined
behavior, the other half are additional objtool annotations
- Update objtool to latest (known) compiler quirks and objtool bugs
triggered by compiler code generation
- Misc fixes"
* tag 'objtool-urgent-2025-04-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
objtool/loongarch: Add unwind hints in prepare_frametrace()
rcu-tasks: Always inline rcu_irq_work_resched()
context_tracking: Always inline ct_{nmi,irq}_{enter,exit}()
sched/smt: Always inline sched_smt_active()
objtool: Fix verbose disassembly if CROSS_COMPILE isn't set
objtool: Change "warning:" to "error: " for fatal errors
objtool: Always fail on fatal errors
Revert "objtool: Increase per-function WARN_FUNC() rate limit"
objtool: Append "()" to function name in "unexpected end of section" warning
objtool: Ignore end-of-section jumps for KCOV/GCOV
objtool: Silence more KCOV warnings, part 2
objtool, drm/vmwgfx: Don't ignore vmw_send_msg() for ORC
objtool: Fix STACK_FRAME_NON_STANDARD for cold subfunctions
objtool: Fix segfault in ignore_unreachable_insn()
objtool: Fix NULL printf() '%s' argument in builtin-check.c:save_argv()
objtool, lkdtm: Obfuscate the do_nothing() pointer
objtool, regulator: rk808: Remove potential undefined behavior in rk806_set_mode_dcdc()
objtool, ASoC: codecs: wcd934x: Remove potential undefined behavior in wcd934x_slim_irq_handler()
objtool, Input: cyapa - Remove undefined behavior in cyapa_update_fw_store()
objtool, panic: Disable SMAP in __stack_chk_fail()
...
Pull more printk updates from Petr Mladek:
- Silence warnings about candidates for ‘gnu_print’ format attribute
* tag 'printk-for-6.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
vsnprintf: Silence false positive GCC warning for va_format()
vsnprintf: Drop unused const char fmt * in va_format()
vsnprintf: Mark binary printing functions with __printf() attribute
tracing: Mark binary printing functions with __printf() attribute
seq_file: Mark binary printing functions with __printf() attribute
seq_buf: Mark binary printing functions with __printf() attribute
Pull RCU fix from Boqun Feng:
- srcu: Make FORCE_NEED_SRCU_NMI_SAFE depend on RCU_EXPERT
* tag 'rcu-fixes-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux:
srcu: Make FORCE_NEED_SRCU_NMI_SAFE depend on RCU_EXPERT
Pull kgdb updates from Daniel Thompson:
"Two cleanups this cycle. The larger of which is the removal of a
private allocator within kdb and replacing it with regular memory
allocation. The other adopts the simplified version of strscpy() in a
couple of places in kdb"
* tag 'kgdb-6.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kdb: Remove optional size arguments from strscpy() calls
kdb: remove usage of static environment buffer
The reserve_mem kernel command line option may pass back a physical
address, but the memory is still part of the normal memory just like
using memblock_alloc() would be. This means that the physical memory
returned by the reserve_mem command line option can be converted directly
to virtual memory by simply using phys_to_virt().
When freeing the buffer there's no need to call vunmap() anymore as the
memory allocated by reserve_mem is freed by the call to
reserve_mem_release_by_name().
Because the persistent ring buffer can also be allocated via the memmap
option, which *is* different than normal memory as it cannot be added back
to the buddy system, it must be treated differently. It still needs to be
virtually mapped to have access to it. It also can not be freed nor can it
ever be memory mapped to user space.
Create a new trace_array flag called TRACE_ARRAY_FL_MEMMAP which gets set
if the buffer is created by the memmap option, and this will prevent the
buffer from being memory mapped by user space.
Also increment the ref count for memmap'ed buffers so that they can never
be freed.
Link: https://lore.kernel.org/all/Z-wFszhJ_9o4dc8O@kernel.org/
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Vincent Donnefort <vdonnefort@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/20250402144953.583750106@goodmis.org
Suggested-by: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The trace event verifier checks the formats of trace events to make sure
that they do not point at memory that is not in the trace event itself or
in data that will never be freed. If an event references data that was
allocated when the event triggered and that same data is freed before the
event is read, then the kernel can crash by reading freed memory.
The verifier runs at boot up (or module load) and scans the print formats
of the events and checks their arguments to make sure that dereferenced
pointers are safe. If the format uses "%*p.." the verifier will ignore it,
and that could be dangerous. Cover this case as well.
Also add to the sample code a use case of "%*pbl".
Link: https://lore.kernel.org/all/bcba4d76-2c3f-4d11-baf0-02905db953dd@oracle.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers")
Link: https://lore.kernel.org/20250327195311.2d89ec66@gandalf.local.home
Reported-by: Libo Chen <libo.chen@oracle.com>
Reviewed-by: Libo Chen <libo.chen@oracle.com>
Tested-by: Libo Chen <libo.chen@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
