execmem does not depend on modules, on the contrary modules use
execmem.
To make execmem available when CONFIG_MODULES=n, for instance for
kprobes, split execmem_params initialization out from
arch/*/kernel/module.c and compile it when CONFIG_EXECMEM=y
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Several architectures override module_alloc() only to define address
range for code allocations different than VMALLOC address space.
Provide a generic implementation in execmem that uses the parameters for
address space ranges, required alignment and page protections provided
by architectures.
The architectures must fill execmem_info structure and implement
execmem_arch_setup() that returns a pointer to that structure. This way the
execmem initialization won't be called from every architecture, but rather
from a central place, namely a core_initcall() in execmem.
The execmem provides execmem_alloc() API that wraps __vmalloc_node_range()
with the parameters defined by the architectures. If an architecture does
not implement execmem_arch_setup(), execmem_alloc() will fall back to
module_alloc().
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
nios2 uses kmalloc() to implement module_alloc() because CALL26/PCREL26
cannot reach all of vmalloc address space.
Define module space as 32MiB below the kernel base and switch nios2 to
use vmalloc for module allocations.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Starting with commit 7b937cc243 ("of: Create of_root if no dtb provided
by firmware"), attempts to boot nios2 images with an external devicetree
blob result in a crash.
Kernel panic - not syncing: early_init_dt_alloc_memory_arch:
Failed to allocate 72 bytes align=0x40
For nios2, a built-in devicetree blob always overrides devicetree blobs
provided by ROMMON/BIOS. This includes the new dummy devicetree blob.
Result is that the dummy devicetree blob is used even if an external
devicetree blob is provided. Since the dummy devicetree blob does not
include any memory information, memory allocations fail, resulting in
the crash.
To fix the problem, only use the built-in devicetree blob if
CONFIG_NIOS2_DTB_SOURCE_BOOL is enabled.
Fixes: 7b937cc243 ("of: Create of_root if no dtb provided by firmware")
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20240322065419.162416-1-linux@roeck-us.net
Signed-off-by: Rob Herring <robh@kernel.org>
A number of architectures either kept the screen_info definition for
historical purposes as it used to be required by the generic VT code, or
they copied it from another architecture in order to build the VGA console
driver in an allmodconfig build. The mips definition is used by some
platforms, but the initialization on jazz is not needed.
Now that vgacon no longer builds on these architectures, remove the
stale definitions and initializations.
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20231009211845.3136536-5-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.
[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Current arch_cpu_idle() is called with IRQs disabled, but will return
with IRQs enabled.
However, the very first thing the generic code does after calling
arch_cpu_idle() is raw_local_irq_disable(). This means that
architectures that can idle with IRQs disabled end up doing a
pointless 'enable-disable' dance.
Therefore, push this IRQ disabling into the idle function, meaning
that those architectures can avoid the pointless IRQ state flipping.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Acked-by: Mark Rutland <mark.rutland@arm.com> [arm64]
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195540.618076436@infradead.org
Idle code is very like entry code in that RCU isn't available. As
such, add a little validation.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195540.373461409@infradead.org
user_regset_copyin_ignore() always returns 0, so checking its result seems
pointless -- don't do this anymore...
Link: https://lkml.kernel.org/r/20221014212235.10770-8-s.shtylyov@omp.ru
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David S. Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.osdn.me>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The objects placed at the head of vmlinux need special treatments:
- arch/$(SRCARCH)/Makefile adds them to head-y in order to place
them before other archives in the linker command line.
- arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of
obj-y to avoid them going into built-in.a.
This commit gets rid of the latter.
Create vmlinux.a to collect all the objects that are unconditionally
linked to vmlinux. The objects listed in head-y are moved to the head
of vmlinux.a by using 'ar m'.
With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y
for builtin objects.
There is no *.o that is directly linked to vmlinux. Drop unneeded code
in scripts/clang-tools/gen_compile_commands.py.
$(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested
by Nathan Chancellor [1].
[1]: https://lore.kernel.org/llvm/YyjjT5gQ2hGMH0ni@dev-arch.thelio-3990X/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
If we use the ancient SysV syscall ABI, we'd better have tell the
kernel how to claim that a negative return value is a success.
Use ->orig_r2 for that - it's inaccessible via ptrace, so it's
a fair game for changes and it's normally[*] non-negative on return
from syscall. Set to -1; syscall is not going to be restart-worthy
by definition, so we won't interfere with that use either.
[*] the only exception is rt_sigreturn(), where we skip the entire
messing with r1/r2 anyway.
Fixes: 82ed08dd1b ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
sys_foo() returns -512 (aka -ERESTARTSYS) => do_signal() sees
512 in r2 and 1 in r1.
sys_foo() returns 512 => do_signal() sees 512 in r2 and 0 in r1.
The former is restart-worthy; the latter obviously isn't.
Fixes: b53e906d25 ("nios2: Signal handling support")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
all checks done before letting the tracer modify the register
state are worthless...
Fixes: 82ed08dd1b ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
fill the gaps in there with sys_ni_syscall, as everyone does...
Fixes: 82ed08dd1b ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
make sure that ->orig_r2 is negative for everything except
the syscalls.
Fixes: 82ed08dd1b ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Add fn and fn_arg members into struct kernel_clone_args and test for
them in copy_thread (instead of testing for PF_KTHREAD | PF_IO_WORKER).
This allows any task that wants to be a user space task that only runs
in kernel mode to use this functionality.
The code on x86 is an exception and still retains a PF_KTHREAD test
because x86 unlikely everything else handles kthreads slightly
differently than user space tasks that start with a function.
The functions that created tasks that start with a function
have been updated to set ".fn" and ".fn_arg" instead of
".stack" and ".stack_size". These functions are fork_idle(),
create_io_thread(), kernel_thread(), and user_mode_thread().
Link: https://lkml.kernel.org/r/20220506141512.516114-4-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
With io_uring we have started supporting tasks that are for most
purposes user space tasks that exclusively run code in kernel mode.
The kernel task that exec's init and tasks that exec user mode
helpers are also user mode tasks that just run kernel code
until they call kernel execve.
Pass kernel_clone_args into copy_thread so these oddball
tasks can be supported more cleanly and easily.
v2: Fix spelling of kenrel_clone_args on h8300
Link: https://lkml.kernel.org/r/20220506141512.516114-2-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This set of changes removes tracehook.h, moves modification of all of
the ptrace fields inside of siglock to remove races, adds a missing
permission check to ptrace.c
The removal of tracehook.h is quite significant as it has been a major
source of confusion in recent years. Much of that confusion was
around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled
making the semantics clearer).
For people who don't know tracehook.h is a vestiage of an attempt to
implement uprobes like functionality that was never fully merged, and
was later superseeded by uprobes when uprobes was merged. For many
years now we have been removing what tracehook functionaly a little
bit at a time. To the point where now anything left in tracehook.h is
some weird strange thing that is difficult to understand.
Eric W. Biederman (15):
ptrace: Move ptrace_report_syscall into ptrace.h
ptrace/arm: Rename tracehook_report_syscall report_syscall
ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
ptrace: Remove arch_syscall_{enter,exit}_tracehook
ptrace: Remove tracehook_signal_handler
task_work: Remove unnecessary include from posix_timers.h
task_work: Introduce task_work_pending
task_work: Call tracehook_notify_signal from get_signal on all architectures
task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
resume_user_mode: Move to resume_user_mode.h
tracehook: Remove tracehook.h
ptrace: Move setting/clearing ptrace_message into ptrace_stop
ptrace: Return the signal to continue with from ptrace_stop
Jann Horn (1):
ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
Yang Li (1):
ptrace: Remove duplicated include in ptrace.c
MAINTAINERS | 1 -
arch/Kconfig | 5 +-
arch/alpha/kernel/ptrace.c | 5 +-
arch/alpha/kernel/signal.c | 4 +-
arch/arc/kernel/ptrace.c | 5 +-
arch/arc/kernel/signal.c | 4 +-
arch/arm/kernel/ptrace.c | 12 +-
arch/arm/kernel/signal.c | 4 +-
arch/arm64/kernel/ptrace.c | 14 +--
arch/arm64/kernel/signal.c | 4 +-
arch/csky/kernel/ptrace.c | 5 +-
arch/csky/kernel/signal.c | 4 +-
arch/h8300/kernel/ptrace.c | 5 +-
arch/h8300/kernel/signal.c | 4 +-
arch/hexagon/kernel/process.c | 4 +-
arch/hexagon/kernel/signal.c | 1 -
arch/hexagon/kernel/traps.c | 6 +-
arch/ia64/kernel/process.c | 4 +-
arch/ia64/kernel/ptrace.c | 6 +-
arch/ia64/kernel/signal.c | 1 -
arch/m68k/kernel/ptrace.c | 5 +-
arch/m68k/kernel/signal.c | 4 +-
arch/microblaze/kernel/ptrace.c | 5 +-
arch/microblaze/kernel/signal.c | 4 +-
arch/mips/kernel/ptrace.c | 5 +-
arch/mips/kernel/signal.c | 4 +-
arch/nds32/include/asm/syscall.h | 2 +-
arch/nds32/kernel/ptrace.c | 5 +-
arch/nds32/kernel/signal.c | 4 +-
arch/nios2/kernel/ptrace.c | 5 +-
arch/nios2/kernel/signal.c | 4 +-
arch/openrisc/kernel/ptrace.c | 5 +-
arch/openrisc/kernel/signal.c | 4 +-
arch/parisc/kernel/ptrace.c | 7 +-
arch/parisc/kernel/signal.c | 4 +-
arch/powerpc/kernel/ptrace/ptrace.c | 8 +-
arch/powerpc/kernel/signal.c | 4 +-
arch/riscv/kernel/ptrace.c | 5 +-
arch/riscv/kernel/signal.c | 4 +-
arch/s390/include/asm/entry-common.h | 1 -
arch/s390/kernel/ptrace.c | 1 -
arch/s390/kernel/signal.c | 5 +-
arch/sh/kernel/ptrace_32.c | 5 +-
arch/sh/kernel/signal_32.c | 4 +-
arch/sparc/kernel/ptrace_32.c | 5 +-
arch/sparc/kernel/ptrace_64.c | 5 +-
arch/sparc/kernel/signal32.c | 1 -
arch/sparc/kernel/signal_32.c | 4 +-
arch/sparc/kernel/signal_64.c | 4 +-
arch/um/kernel/process.c | 4 +-
arch/um/kernel/ptrace.c | 5 +-
arch/x86/kernel/ptrace.c | 1 -
arch/x86/kernel/signal.c | 5 +-
arch/x86/mm/tlb.c | 1 +
arch/xtensa/kernel/ptrace.c | 5 +-
arch/xtensa/kernel/signal.c | 4 +-
block/blk-cgroup.c | 2 +-
fs/coredump.c | 1 -
fs/exec.c | 1 -
fs/io-wq.c | 6 +-
fs/io_uring.c | 11 +-
fs/proc/array.c | 1 -
fs/proc/base.c | 1 -
include/asm-generic/syscall.h | 2 +-
include/linux/entry-common.h | 47 +-------
include/linux/entry-kvm.h | 2 +-
include/linux/posix-timers.h | 1 -
include/linux/ptrace.h | 81 ++++++++++++-
include/linux/resume_user_mode.h | 64 ++++++++++
include/linux/sched/signal.h | 17 +++
include/linux/task_work.h | 5 +
include/linux/tracehook.h | 226 -----------------------------------
include/uapi/linux/ptrace.h | 2 +-
kernel/entry/common.c | 19 +--
kernel/entry/kvm.c | 9 +-
kernel/exit.c | 3 +-
kernel/livepatch/transition.c | 1 -
kernel/ptrace.c | 47 +++++---
kernel/seccomp.c | 1 -
kernel/signal.c | 62 +++++-----
kernel/task_work.c | 4 +-
kernel/time/posix-cpu-timers.c | 1 +
mm/memcontrol.c | 2 +-
security/apparmor/domain.c | 1 -
security/selinux/hooks.c | 1 -
85 files changed, 372 insertions(+), 495 deletions(-)
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull ptrace cleanups from Eric Biederman:
"This set of changes removes tracehook.h, moves modification of all of
the ptrace fields inside of siglock to remove races, adds a missing
permission check to ptrace.c
The removal of tracehook.h is quite significant as it has been a major
source of confusion in recent years. Much of that confusion was around
task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the
semantics clearer).
For people who don't know tracehook.h is a vestiage of an attempt to
implement uprobes like functionality that was never fully merged, and
was later superseeded by uprobes when uprobes was merged. For many
years now we have been removing what tracehook functionaly a little
bit at a time. To the point where anything left in tracehook.h was
some weird strange thing that was difficult to understand"
* tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
ptrace: Remove duplicated include in ptrace.c
ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
ptrace: Return the signal to continue with from ptrace_stop
ptrace: Move setting/clearing ptrace_message into ptrace_stop
tracehook: Remove tracehook.h
resume_user_mode: Move to resume_user_mode.h
resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
task_work: Call tracehook_notify_signal from get_signal on all architectures
task_work: Introduce task_work_pending
task_work: Remove unnecessary include from posix_timers.h
ptrace: Remove tracehook_signal_handler
ptrace: Remove arch_syscall_{enter,exit}_tracehook
ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
ptrace/arm: Rename tracehook_report_syscall report_syscall
ptrace: Move ptrace_report_syscall into ptrace.h
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h.
While doing that rename tracehook_notify_resume to resume_user_mode_work.
Update all of the places that included tracehook.h for these functions to
include resume_user_mode.h instead.
Update all of the callers of tracehook_notify_resume to call
resume_user_mode_work.
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Rename tracehook_report_syscall_{entry,exit} to
ptrace_report_syscall_{entry,exit} and place them in ptrace.h
There is no longer any generic tracehook infractructure so make
these ptrace specific functions ptrace specific.
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20220309162454.123006-3-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
On some architectures, access_ok() does not do any argument type
checking, so replacing the definition with a generic one causes
a few warnings for harmless issues that were never caught before.
Fix the ones that I found either through my own test builds or
that were reported by the 0-day bot.
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
There are two big uses of do_exit. The first is it's design use to be
the guts of the exit(2) system call. The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.
Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure. In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.
Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.
As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Having a stable wchan means the process must be blocked and for it to
stay that way while performing stack unwinding.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm]
Tested-by: Mark Rutland <mark.rutland@arm.com> [arm64]
Link: https://lkml.kernel.org/r/20211008111626.332092234@infradead.org
This is a nuisance when CONFIG_WERROR is set, so drop the variable
declaration since the code that used it was removed.
../arch/nios2/kernel/setup.c: In function 'setup_arch':
../arch/nios2/kernel/setup.c:152:13: warning: unused variable 'dram_start' [-Wunused-variable]
152 | int dram_start;
Fixes: 7f7bc20bc4 ("nios2: Don't use _end for calculating min_low_pfn")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Andreas Oetken <andreas.oetken@siemens.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Merge more updates from Andrew Morton:
"147 patches, based on 7d2a07b769.
Subsystems affected by this patch series: mm (memory-hotplug, rmap,
ioremap, highmem, cleanups, secretmem, kfence, damon, and vmscan),
alpha, percpu, procfs, misc, core-kernel, MAINTAINERS, lib,
checkpatch, epoll, init, nilfs2, coredump, fork, pids, criu, kconfig,
selftests, ipc, and scripts"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
scripts: check_extable: fix typo in user error message
mm/workingset: correct kernel-doc notations
ipc: replace costly bailout check in sysvipc_find_ipc()
selftests/memfd: remove unused variable
Kconfig.debug: drop selecting non-existing HARDLOCKUP_DETECTOR_ARCH
configs: remove the obsolete CONFIG_INPUT_POLLDEV
prctl: allow to setup brk for et_dyn executables
pid: cleanup the stale comment mentioning pidmap_init().
kernel/fork.c: unexport get_{mm,task}_exe_file
coredump: fix memleak in dump_vma_snapshot()
fs/coredump.c: log if a core dump is aborted due to changed file permissions
nilfs2: use refcount_dec_and_lock() to fix potential UAF
nilfs2: fix memory leak in nilfs_sysfs_delete_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_create_snapshot_group
nilfs2: fix memory leak in nilfs_sysfs_delete_##name##_group
nilfs2: fix memory leak in nilfs_sysfs_create_##name##_group
nilfs2: fix NULL pointer in nilfs_##name##_attr_release
nilfs2: fix memory leak in nilfs_sysfs_create_device_group
trap: cleanup trap_init()
init: move usermodehelper_enable() to populate_rootfs()
...
There are some empty trap_init() definitions in different ARCHs, Introduce
a new weak trap_init() function to clean them up.
Link: https://lkml.kernel.org/r/20210812123602.76356-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [arm32]
Acked-by: Vineet Gupta [arc]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <palmerdabbelt@google.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wherever possible, replace constructs that match either
generic_handle_irq(irq_find_mapping()) or
generic_handle_irq(irq_linear_revmap()) to a single call to
generic_handle_domain_irq().
Signed-off-by: Marc Zyngier <maz@kernel.org>
Use setup_initial_init_mm() helper to simplify code.
Link: https://lkml.kernel.org/r/20210608083418.137226-10-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Core changes:
- Cleanup and simplification of common code to invoke the low level
interrupt flow handlers when this invocation requires irqdomain
resolution. Add the necessary core infrastructure.
- Provide a proper interface for modular PMU drivers to set the
interrupt affinity.
- Add a request flag which allows to exclude interrupts from spurious
interrupt detection. Useful especially for IPI handlers which always
return IRQ_HANDLED which turns the spurious interrupt detection into a
pointless waste of CPU cycles.
Driver changes:
- Bulk convert interrupt chip drivers to the new irqdomain low level flow
handler invocation mechanism.
- Add device tree bindings for the Renesas R-Car M3-W+ SoC
- Enable modular build of the Qualcomm PDC driver
- The usual small fixes and improvements.
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Merge tag 'irq-core-2021-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"Updates for the interrupt subsystem:
Core changes:
- Cleanup and simplification of common code to invoke the low level
interrupt flow handlers when this invocation requires irqdomain
resolution. Add the necessary core infrastructure.
- Provide a proper interface for modular PMU drivers to set the
interrupt affinity.
- Add a request flag which allows to exclude interrupts from spurious
interrupt detection. Useful especially for IPI handlers which
always return IRQ_HANDLED which turns the spurious interrupt
detection into a pointless waste of CPU cycles.
Driver changes:
- Bulk convert interrupt chip drivers to the new irqdomain low level
flow handler invocation mechanism.
- Add device tree bindings for the Renesas R-Car M3-W+ SoC
- Enable modular build of the Qualcomm PDC driver
- The usual small fixes and improvements"
* tag 'irq-core-2021-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
dt-bindings: interrupt-controller: arm,gic-v3: Describe GICv3 optional properties
irqchip: gic-pm: Remove redundant error log of clock bulk
irqchip/sun4i: Remove unnecessary oom message
irqchip/irq-imx-gpcv2: Remove unnecessary oom message
irqchip/imgpdc: Remove unnecessary oom message
irqchip/gic-v3-its: Remove unnecessary oom message
irqchip/gic-v2m: Remove unnecessary oom message
irqchip/exynos-combiner: Remove unnecessary oom message
irqchip: Bulk conversion to generic_handle_domain_irq()
genirq: Move non-irqdomain handle_domain_irq() handling into ARM's handle_IRQ()
genirq: Add generic_handle_domain_irq() helper
irqchip/nvic: Convert from handle_IRQ() to handle_domain_irq()
irqdesc: Fix __handle_domain_irq() comment
genirq: Use irq_resolve_mapping() to implement __handle_domain_irq() and co
irqdomain: Introduce irq_resolve_mapping()
irqdomain: Protect the linear revmap with RCU
irqdomain: Cache irq_data instead of a virq number in the revmap
irqdomain: Use struct_size() helper when allocating irqdomain
irqdomain: Make normal and nomap irqdomains exclusive
powerpc: Move the use of irq_domain_add_nomap() behind a config option
...
Replace a bunch of 'p->state == TASK_RUNNING' with a new helper:
task_is_running(p).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210611082838.222401495@infradead.org
Including linux/irqdomain.h from asm/irq.h is going to break
as soon as linux/irqdomain.h will include linux/irq.h, so
let's fix this. Code relying on linux/irqomain.h should include
it directly.
Signed-off-by: Marc Zyngier <maz@kernel.org>
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Merge tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block
Pull io_uring thread rewrite from Jens Axboe:
"This converts the io-wq workers to be forked off the tasks in question
instead of being kernel threads that assume various bits of the
original task identity.
This kills > 400 lines of code from io_uring/io-wq, and it's the worst
part of the code. We've had several bugs in this area, and the worry
is always that we could be missing some pieces for file types doing
unusual things (recent /dev/tty example comes to mind, userfaultfd
reads installing file descriptors is another fun one... - both of
which need special handling, and I bet it's not the last weird oddity
we'll find).
With these identical workers, we can have full confidence that we're
never missing anything. That, in itself, is a huge win. Outside of
that, it's also more efficient since we're not wasting space and code
on tracking state, or switching between different states.
I'm sure we're going to find little things to patch up after this
series, but testing has been pretty thorough, from the usual
regression suite to production. Any issue that may crop up should be
manageable.
There's also a nice series of further reductions we can do on top of
this, but I wanted to get the meat of it out sooner rather than later.
The general worry here isn't that it's fundamentally broken. Most of
the little issues we've found over the last week have been related to
just changes in how thread startup/exit is done, since that's the main
difference between using kthreads and these kinds of threads. In fact,
if all goes according to plan, I want to get this into the 5.10 and
5.11 stable branches as well.
That said, the changes outside of io_uring/io-wq are:
- arch setup, simple one-liner to each arch copy_thread()
implementation.
- Removal of net and proc restrictions for io_uring, they are no
longer needed or useful"
* tag 'io_uring-worker.v3-2021-02-25' of git://git.kernel.dk/linux-block: (30 commits)
io-wq: remove now unused IO_WQ_BIT_ERROR
io_uring: fix SQPOLL thread handling over exec
io-wq: improve manager/worker handling over exec
io_uring: ensure SQPOLL startup is triggered before error shutdown
io-wq: make buffered file write hashed work map per-ctx
io-wq: fix race around io_worker grabbing
io-wq: fix races around manager/worker creation and task exit
io_uring: ensure io-wq context is always destroyed for tasks
arch: ensure parisc/powerpc handle PF_IO_WORKER in copy_thread()
io_uring: cleanup ->user usage
io-wq: remove nr_process accounting
io_uring: flag new native workers with IORING_FEAT_NATIVE_WORKERS
net: remove cmsg restriction from io_uring based send/recvmsg calls
Revert "proc: don't allow async path resolution of /proc/self components"
Revert "proc: don't allow async path resolution of /proc/thread-self components"
io_uring: move SQPOLL thread io-wq forked worker
io-wq: make io_wq_fork_thread() available to other users
io-wq: only remove worker from free_list, if it was there
io_uring: remove io_identity
io_uring: remove any grabbing of context
...
PF_IO_WORKER are kernel threads too, but they aren't PF_KTHREAD in the
sense that we don't assign ->set_child_tid with our own structure. Just
ensure that every arch sets up the PF_IO_WORKER threads like kthreads
in the arch implementation of copy_thread().
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If there is a initramfs linked into the kernel which will be
freed later on there is free memory somewhere between _etext
and _end, thus using _end for min_low_pfn is not correct.
This may lead to issues in dma_capable when checking
'min(addr, end) < phys_to_dma(dev, PFN_PHYS(min_low_pfn)))'
as the address addr might be below min_low_pfn. Picked
find_limits from architecture arm for applying min_low_pfn and
max_low_pfn. Maybe using _etext for min_low_pfn would be
fine too.
Signed-off-by: Andreas Oetken <andreas.oetken@siemens.com>
Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
The tls pointer must be pushed on the stack prior to calling nios2_clone
as it is the 5th function argument. Prior handling of the tls pointer was
done inside former called function copy_thread_tls using the r8 register
from the current_pt_regs directly. This was a bad design and resulted in
the current bug introduced in 04bd52fb.
Fixes: 04bd52fb ("nios2: enable HAVE_COPY_THREAD_TLS, switch to kernel_clone_args")
Signed-off-by: Andreas Oetken <andreas.oetken@siemens.com>
Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
We need to take the mmap lock around find_vma() and subsequent use of the
VMA. Otherwise, we can race with concurrent operations like munmap(), which
can lead to use-after-free accesses to freed VMAs.
Fixes: 1000197d80 ("nios2: System calls handling")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Ley Foon Tan <ley.foon.tan@intel.com>
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Merge tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block
Pull TIF_NOTIFY_SIGNAL updates from Jens Axboe:
"This sits on top of of the core entry/exit and x86 entry branch from
the tip tree, which contains the generic and x86 parts of this work.
Here we convert the rest of the archs to support TIF_NOTIFY_SIGNAL.
With that done, we can get rid of JOBCTL_TASK_WORK from task_work and
signal.c, and also remove a deadlock work-around in io_uring around
knowing that signal based task_work waking is invoked with the sighand
wait queue head lock.
The motivation for this work is to decouple signal notify based
task_work, of which io_uring is a heavy user of, from sighand. The
sighand lock becomes a huge contention point, particularly for
threaded workloads where it's shared between threads. Even outside of
threaded applications it's slower than it needs to be.
Roman Gershman <romger@amazon.com> reported that his networked
workload dropped from 1.6M QPS at 80% CPU to 1.0M QPS at 100% CPU
after io_uring was changed to use TIF_NOTIFY_SIGNAL. The time was all
spent hammering on the sighand lock, showing 57% of the CPU time there
[1].
There are further cleanups possible on top of this. One example is
TIF_PATCH_PENDING, where a patch already exists to use
TIF_NOTIFY_SIGNAL instead. Hopefully this will also lead to more
consolidation, but the work stands on its own as well"
[1] https://github.com/axboe/liburing/issues/215
* tag 'tif-task_work.arch-2020-12-14' of git://git.kernel.dk/linux-block: (28 commits)
io_uring: remove 'twa_signal_ok' deadlock work-around
kernel: remove checking for TIF_NOTIFY_SIGNAL
signal: kill JOBCTL_TASK_WORK
io_uring: JOBCTL_TASK_WORK is no longer used by task_work
task_work: remove legacy TWA_SIGNAL path
sparc: add support for TIF_NOTIFY_SIGNAL
riscv: add support for TIF_NOTIFY_SIGNAL
nds32: add support for TIF_NOTIFY_SIGNAL
ia64: add support for TIF_NOTIFY_SIGNAL
h8300: add support for TIF_NOTIFY_SIGNAL
c6x: add support for TIF_NOTIFY_SIGNAL
alpha: add support for TIF_NOTIFY_SIGNAL
xtensa: add support for TIF_NOTIFY_SIGNAL
arm: add support for TIF_NOTIFY_SIGNAL
microblaze: add support for TIF_NOTIFY_SIGNAL
hexagon: add support for TIF_NOTIFY_SIGNAL
csky: add support for TIF_NOTIFY_SIGNAL
openrisc: add support for TIF_NOTIFY_SIGNAL
sh: add support for TIF_NOTIFY_SIGNAL
um: add support for TIF_NOTIFY_SIGNAL
...
We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.
Switch all arch_cpu_idle() implementations to use
raw_local_irq_{en,dis}able() and carefully manage the
lockdep,rcu,tracing state like we do in entry.
(XXX: we really should change arch_cpu_idle() to not return with
interrupts enabled)
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
Wire up TIF_NOTIFY_SIGNAL handling for nios32.
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
All the callers currently do this, clean it up and move the clearing
into tracehook_notify_resume() instead.
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'kernel-clone-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull kernel_clone() updates from Christian Brauner:
"During the v5.9 merge window we reworked the process creation
codepaths across multiple architectures. After this work we were only
left with the _do_fork() helper based on the struct kernel_clone_args
calling convention. As was pointed out _do_fork() isn't valid
kernelese especially for a helper that isn't just static.
This series removes the _do_fork() helper and introduces the new
kernel_clone() helper. The process creation cleanup didn't change the
name to something more reasonable mainly because _do_fork() was used
in quite a few places. So sending this as a separate series seemed the
better strategy.
I originally intended to send this early in the v5.9 development cycle
after the merge window had closed but given that this was touching
quite a few places I decided to defer this until the v5.10 merge
window"
* tag 'kernel-clone-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
sched: remove _do_fork()
tracing: switch to kernel_clone()
kgdbts: switch to kernel_clone()
kprobes: switch to kernel_clone()
x86: switch to kernel_clone()
sparc: switch to kernel_clone()
nios2: switch to kernel_clone()
m68k: switch to kernel_clone()
ia64: switch to kernel_clone()
h8300: switch to kernel_clone()
fork: introduce kernel_clone()
The .comment section doesn't belong in STABS_DEBUG. Split it out into a
new macro named ELF_DETAILS. This will gain other non-debug sections
that need to be accounted for when linking with --orphan-handling=warn.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20200821194310.3089815-5-keescook@chromium.org
The old _do_fork() helper is removed in favor of the new kernel_clone() helper.
The latter adheres to naming conventions for kernel internal syscall helpers.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Link: https://lore.kernel.org/r/20200819104655.436656-6-christian.brauner@ubuntu.com
Pull regset conversion fix from Al Viro:
"Fix a regression from an unnoticed bisect hazard in the regset series.
A bunch of old (aout, originally) primitives used by coredumps became
dead code after fdpic conversion to regsets. Removal of that dead code
had been the first commit in the followups to regset series;
unfortunately, it happened to hide the bisect hazard on sh (extern for
fpregs_get() had not been updated in the main series when it should
have been; followup simply made fpregs_get() static). And without that
followup commit this bisect hazard became breakage in the mainline"
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
kill unused dump_fpu() instances
Pull ptrace regset updates from Al Viro:
"Internal regset API changes:
- regularize copy_regset_{to,from}_user() callers
- switch to saner calling conventions for ->get()
- kill user_regset_copyout()
The ->put() side of things will have to wait for the next cycle,
unfortunately.
The balance is about -1KLoC and replacements for ->get() instances are
a lot saner"
* 'work.regset' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
regset: kill user_regset_copyout{,_zero}()
regset(): kill ->get_size()
regset: kill ->get()
csky: switch to ->regset_get()
xtensa: switch to ->regset_get()
parisc: switch to ->regset_get()
nds32: switch to ->regset_get()
nios2: switch to ->regset_get()
hexagon: switch to ->regset_get()
h8300: switch to ->regset_get()
openrisc: switch to ->regset_get()
riscv: switch to ->regset_get()
c6x: switch to ->regset_get()
ia64: switch to ->regset_get()
arc: switch to ->regset_get()
arm: switch to ->regset_get()
sh: convert to ->regset_get()
arm64: switch to ->regset_get()
mips: switch to ->regset_get()
sparc: switch to ->regset_get()
...
dump_fpu() is used only on the architectures that support elf
and have neither CORE_DUMP_USE_REGSET nor ELF_CORE_COPY_FPREGS
defined.
Currently that's csky, m68k, microblaze, nds32 and unicore32. The rest
of the instances are dead code.
NB: THIS MUST GO AFTER ELF_FDPIC CONVERSION
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls()
back simply copy_thread(). It's a simpler name, and doesn't imply that only
tls is copied here. This finishes an outstanding chunk of internal process
creation work since we've added clone3().
Cc: linux-arch@vger.kernel.org
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>A
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>A
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
This is part of a larger series that aims at getting rid of the
copy_thread()/copy_thread_tls() split that makes the process creation
codepaths in the kernel more convoluted and error-prone than they need
to be.
I'm converting all the remaining arches that haven't yet switched and
am collecting individual acks. Once I have them, I'll send the whole series
removing the copy_thread()/copy_thread_tls() split, the
HAVE_COPY_THREAD_TLS define and the legacy do_fork() helper. The only
kernel-wide process creation entry point for anything not going directly
through the syscall path will then be based on struct kernel_clone_args.
No more danger of weird process creation abi quirks between architectures
hopefully, and easier to maintain overall.
It also unblocks implementing clone3() on architectures not support
copy_thread_tls(). Any architecture that wants to implement clone3()
will need to select HAVE_COPY_THREAD_TLS and thus need to implement
copy_thread_tls(). So both goals are connected but independently
beneficial.
HAVE_COPY_THREAD_TLS means that a given architecture supports
CLONE_SETTLS and not setting it should usually mean that the
architectures doesn't implement it but that's not how things are. In
fact all architectures support CLONE_TLS it's just that they don't
follow the calling convention that HAVE_COPY_THREAD_TLS implies. That
means all architectures can be switched over to select
HAVE_COPY_THREAD_TLS. Once that is done we can remove that macro (yay,
less code), the unnecessary do_fork() export in kernel/fork.c, and also
rename copy_thread_tls() back to copy_thread(). At this point
copy_thread() becomes the main architecture specific part of process
creation but it will be the same layout and calling convention for all
architectures. (Once that is done we can probably cleanup each
copy_thread() function even more but that's for the future.)
Since nios2 does support CLONE_SETTLS there's no reason to not select
HAVE_COPY_THREAD_TLS. This brings us one step closer to getting rid of
the copy_thread()/copy_thread_tls() split we still have and ultimately
the HAVE_COPY_THREAD_TLS define in general. A lot of architectures have
already converted and nios2 is one of the few hat haven't yet. This also
unblocks implementing the clone3() syscall on nios2. Once that is done we
can get of another ARCH_WANTS_* macro.
Once Any architecture that supports HAVE_COPY_THREAD_TLS cannot call the
do_fork() helper anymore. This is fine and intended since it should be
removed in favor of the new, cleaner _do_fork() calling convention based
on struct kernel_clone_args. In fact, most architectures have already
switched. With this patch, nios2 joins the other arches which can't use
the fork(), vfork(), clone(), clone3() syscalls directly and who follow
the new process creation calling convention that is based on struct
kernel_clone_args which we introduced a while back. This means less
custom assembly in the architectures entry path to set up the registers
before calling into the process creation helper and it is easier to to
support new features without having to adapt calling conventions. It
also unifies all process creation paths between fork(), vfork(),
clone(), and clone3(). (We can't fix the ABI nightmare that legacy
clone() is but we can prevent stuff like this happening in the future.)
For some more context, please see:
commit 606e9ad200
Merge: ac61145a72457677c70c
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sat Jan 11 15:33:48 2020 -0800
Merge tag 'clone3-tls-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread fixes from Christian Brauner:
"This contains a series of patches to fix CLONE_SETTLS when used with
clone3().
The clone3() syscall passes the tls argument through struct clone_args
instead of a register. This means, all architectures that do not
implement copy_thread_tls() but still support CLONE_SETTLS via
copy_thread() expecting the tls to be located in a register argument
based on clone() are currently unfortunately broken. Their tls value
will be garbage.
The patch series fixes this on all architectures that currently define
__ARCH_WANT_SYS_CLONE3. It also adds a compile-time check to ensure
that any architecture that enables clone3() in the future is forced to
also implement copy_thread_tls().
My ultimate goal is to get rid of the copy_thread()/copy_thread_tls()
split and just have copy_thread_tls() at some point in the not too
distant future (Maybe even renaming copy_thread_tls() back to simply
copy_thread() once the old function is ripped from all arches). This
is dependent now on all arches supporting clone3().
While all relevant arches do that now there are still four missing:
ia64, m68k, sh and sparc. They have the system call reserved, but not
implemented. Once they all implement clone3() we can get rid of
ARCH_WANT_SYS_CLONE3 and HAVE_COPY_THREAD_TLS.
Note that in the meantime, m68k has already switched to the new calling
convention. And I've got sparc patches acked by Dave and ia64 is already
done too. You can find a link to a booting qemu nios2 system with all the
changes here at [1].
[1]: https://asciinema.org/a/333353
Cc: linux-kernel@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Mike Rapoport (IBM)