26 Oct, 2020
1 commit
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Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.Remove the quote operator # from compiler_attributes.h __section macro.
Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.Conversion done using the script at:
https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl
Signed-off-by: Joe Perches
Reviewed-by: Nick Desaulniers
Reviewed-by: Miguel Ojeda
Signed-off-by: Linus Torvalds
24 Oct, 2020
1 commit
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Pull arch task_work cleanups from Jens Axboe:
"Two cleanups that don't fit other categories:- Finally get the task_work_add() cleanup done properly, so we don't
have random 0/1/false/true/TWA_SIGNAL confusing use cases. Updates
all callers, and also fixes up the documentation for
task_work_add().- While working on some TIF related changes for 5.11, this
TIF_NOTIFY_RESUME cleanup fell out of that. Remove some arch
duplication for how that is handled"* tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block:
task_work: cleanup notification modes
tracehook: clear TIF_NOTIFY_RESUME in tracehook_notify_resume()
19 Oct, 2020
1 commit
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There is usecase that System Management Software(SMS) want to give a
memory hint like MADV_[COLD|PAGEEOUT] to other processes and in the
case of Android, it is the ActivityManagerService.The information required to make the reclaim decision is not known to the
app. Instead, it is known to the centralized userspace
daemon(ActivityManagerService), and that daemon must be able to initiate
reclaim on its own without any app involvement.To solve the issue, this patch introduces a new syscall
process_madvise(2). It uses pidfd of an external process to give the
hint. It also supports vector address range because Android app has
thousands of vmas due to zygote so it's totally waste of CPU and power if
we should call the syscall one by one for each vma.(With testing 2000-vma
syscall vs 1-vector syscall, it showed 15% performance improvement. I
think it would be bigger in real practice because the testing ran very
cache friendly environment).Another potential use case for the vector range is to amortize the cost
ofTLB shootdowns for multiple ranges when using MADV_DONTNEED; this could
benefit users like TCP receive zerocopy and malloc implementations. In
future, we could find more usecases for other advises so let's make it
happens as API since we introduce a new syscall at this moment. With
that, existing madvise(2) user could replace it with process_madvise(2)
with their own pid if they want to have batch address ranges support
feature.ince it could affect other process's address range, only privileged
process(PTRACE_MODE_ATTACH_FSCREDS) or something else(e.g., being the same
UID) gives it the right to ptrace the process could use it successfully.
The flag argument is reserved for future use if we need to extend the API.I think supporting all hints madvise has/will supported/support to
process_madvise is rather risky. Because we are not sure all hints make
sense from external process and implementation for the hint may rely on
the caller being in the current context so it could be error-prone. Thus,
I just limited hints as MADV_[COLD|PAGEOUT] in this patch.If someone want to add other hints, we could hear the usecase and review
it for each hint. It's safer for maintenance rather than introducing a
buggy syscall but hard to fix it later.So finally, the API is as follows,
ssize_t process_madvise(int pidfd, const struct iovec *iovec,
unsigned long vlen, int advice, unsigned int flags);DESCRIPTION
The process_madvise() system call is used to give advice or directions
to the kernel about the address ranges from external process as well as
local process. It provides the advice to address ranges of process
described by iovec and vlen. The goal of such advice is to improve
system or application performance.The pidfd selects the process referred to by the PID file descriptor
specified in pidfd. (See pidofd_open(2) for further information)The pointer iovec points to an array of iovec structures, defined in
as:struct iovec {
void *iov_base; /* starting address */
size_t iov_len; /* number of bytes to be advised */
};The iovec describes address ranges beginning at address(iov_base)
and with size length of bytes(iov_len).The vlen represents the number of elements in iovec.
The advice is indicated in the advice argument, which is one of the
following at this moment if the target process specified by pidfd is
external.MADV_COLD
MADV_PAGEOUTPermission to provide a hint to external process is governed by a
ptrace access mode PTRACE_MODE_ATTACH_FSCREDS check; see ptrace(2).The process_madvise supports every advice madvise(2) has if target
process is in same thread group with calling process so user could
use process_madvise(2) to extend existing madvise(2) to support
vector address ranges.RETURN VALUE
On success, process_madvise() returns the number of bytes advised.
This return value may be less than the total number of requested
bytes, if an error occurred. The caller should check return value
to determine whether a partial advice occurred.FAQ:
Q.1 - Why does any external entity have better knowledge?
Quote from Sandeep
"For Android, every application (including the special SystemServer)
are forked from Zygote. The reason of course is to share as many
libraries and classes between the two as possible to benefit from the
preloading during boot.After applications start, (almost) all of the APIs end up calling into
this SystemServer process over IPC (binder) and back to the
application.In a fully running system, the SystemServer monitors every single
process periodically to calculate their PSS / RSS and also decides
which process is "important" to the user for interactivity.So, because of how these processes start _and_ the fact that the
SystemServer is looping to monitor each process, it does tend to *know*
which address range of the application is not used / useful.Besides, we can never rely on applications to clean things up
themselves. We've had the "hey app1, the system is low on memory,
please trim your memory usage down" notifications for a long time[1].
They rely on applications honoring the broadcasts and very few do.So, if we want to avoid the inevitable killing of the application and
restarting it, some way to be able to tell the OS about unimportant
memory in these applications will be useful.- ssp
Q.2 - How to guarantee the race(i.e., object validation) between when
giving a hint from an external process and get the hint from the target
process?process_madvise operates on the target process's address space as it
exists at the instant that process_madvise is called. If the space
target process can run between the time the process_madvise process
inspects the target process address space and the time that
process_madvise is actually called, process_madvise may operate on
memory regions that the calling process does not expect. It's the
responsibility of the process calling process_madvise to close this
race condition. For example, the calling process can suspend the
target process with ptrace, SIGSTOP, or the freezer cgroup so that it
doesn't have an opportunity to change its own address space before
process_madvise is called. Another option is to operate on memory
regions that the caller knows a priori will be unchanged in the target
process. Yet another option is to accept the race for certain
process_madvise calls after reasoning that mistargeting will do no
harm. The suggested API itself does not provide synchronization. It
also apply other APIs like move_pages, process_vm_write.The race isn't really a problem though. Why is it so wrong to require
that callers do their own synchronization in some manner? Nobody
objects to write(2) merely because it's possible for two processes to
open the same file and clobber each other's writes --- instead, we tell
people to use flock or something. Think about mmap. It never
guarantees newly allocated address space is still valid when the user
tries to access it because other threads could unmap the memory right
before. That's where we need synchronization by using other API or
design from userside. It shouldn't be part of API itself. If someone
needs more fine-grained synchronization rather than process level,
there were two ideas suggested - cookie[2] and anon-fd[3]. Both are
applicable via using last reserved argument of the API but I don't
think it's necessary right now since we have already ways to prevent
the race so don't want to add additional complexity with more
fine-grained optimization model.To make the API extend, it reserved an unsigned long as last argument
so we could support it in future if someone really needs it.Q.3 - Why doesn't ptrace work?
Injecting an madvise in the target process using ptrace would not work
for us because such injected madvise would have to be executed by the
target process, which means that process would have to be runnable and
that creates the risk of the abovementioned race and hinting a wrong
VMA. Furthermore, we want to act the hint in caller's context, not the
callee's, because the callee is usually limited in cpuset/cgroups or
even freezed state so they can't act by themselves quick enough, which
causes more thrashing/kill. It doesn't work if the target process are
ptraced(e.g., strace, debugger, minidump) because a process can have at
most one ptracer.[1] https://developer.android.com/topic/performance/memory"
[2] process_getinfo for getting the cookie which is updated whenever
vma of process address layout are changed - Daniel Colascione -
https://lore.kernel.org/lkml/20190520035254.57579-1-minchan@kernel.org/T/#m7694416fd179b2066a2c62b5b139b14e3894e224[3] anonymous fd which is used for the object(i.e., address range)
validation - Michal Hocko -
https://lore.kernel.org/lkml/20200120112722.GY18451@dhcp22.suse.cz/[minchan@kernel.org: fix process_madvise build break for arm64]
Link: http://lkml.kernel.org/r/20200303145756.GA219683@google.com
[minchan@kernel.org: fix build error for mips of process_madvise]
Link: http://lkml.kernel.org/r/20200508052517.GA197378@google.com
[akpm@linux-foundation.org: fix patch ordering issue]
[akpm@linux-foundation.org: fix arm64 whoops]
[minchan@kernel.org: make process_madvise() vlen arg have type size_t, per Florian]
[akpm@linux-foundation.org: fix i386 build]
[sfr@canb.auug.org.au: fix syscall numbering]
Link: https://lkml.kernel.org/r/20200905142639.49fc3f1a@canb.auug.org.au
[sfr@canb.auug.org.au: madvise.c needs compat.h]
Link: https://lkml.kernel.org/r/20200908204547.285646b4@canb.auug.org.au
[minchan@kernel.org: fix mips build]
Link: https://lkml.kernel.org/r/20200909173655.GC2435453@google.com
[yuehaibing@huawei.com: remove duplicate header which is included twice]
Link: https://lkml.kernel.org/r/20200915121550.30584-1-yuehaibing@huawei.com
[minchan@kernel.org: do not use helper functions for process_madvise]
Link: https://lkml.kernel.org/r/20200921175539.GB387368@google.com
[akpm@linux-foundation.org: pidfd_get_pid() gained an argument]
[sfr@canb.auug.org.au: fix up for "iov_iter: transparently handle compat iovecs in import_iovec"]
Link: https://lkml.kernel.org/r/20200928212542.468e1fef@canb.auug.org.auSigned-off-by: Minchan Kim
Signed-off-by: YueHaibing
Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Reviewed-by: Suren Baghdasaryan
Reviewed-by: Vlastimil Babka
Acked-by: David Rientjes
Cc: Alexander Duyck
Cc: Brian Geffon
Cc: Christian Brauner
Cc: Daniel Colascione
Cc: Jann Horn
Cc: Jens Axboe
Cc: Joel Fernandes
Cc: Johannes Weiner
Cc: John Dias
Cc: Kirill Tkhai
Cc: Michal Hocko
Cc: Oleksandr Natalenko
Cc: Sandeep Patil
Cc: SeongJae Park
Cc: SeongJae Park
Cc: Shakeel Butt
Cc: Sonny Rao
Cc: Tim Murray
Cc: Christian Brauner
Cc: Florian Weimer
Cc:
Link: http://lkml.kernel.org/r/20200302193630.68771-3-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200508183320.GA125527@google.com
Link: http://lkml.kernel.org/r/20200622192900.22757-4-minchan@kernel.org
Link: https://lkml.kernel.org/r/20200901000633.1920247-4-minchan@kernel.org
Signed-off-by: Linus Torvalds
18 Oct, 2020
1 commit
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All the callers currently do this, clean it up and move the clearing
into tracehook_notify_resume() instead.Reviewed-by: Oleg Nesterov
Reviewed-by: Thomas Gleixner
Signed-off-by: Jens Axboe
06 Oct, 2020
2 commits
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Move more nitty gritty DMA implementation details into the common
internal header.Signed-off-by: Christoph Hellwig
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Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.Signed-off-by: Christoph Hellwig
24 Aug, 2020
1 commit
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Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through
Signed-off-by: Gustavo A. R. Silva
15 Aug, 2020
1 commit
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Since commit 61a47c1ad3a4dc ("sysctl: Remove the sysctl system call"),
sys_sysctl is actually unavailable: any input can only return an error.We have been warning about people using the sysctl system call for years
and believe there are no more users. Even if there are users of this
interface if they have not complained or fixed their code by now they
probably are not going to, so there is no point in warning them any
longer.So completely remove sys_sysctl on all architectures.
[nixiaoming@huawei.com: s390: fix build error for sys_call_table_emu]
Link: http://lkml.kernel.org/r/20200618141426.16884-1-nixiaoming@huawei.comSigned-off-by: Xiaoming Ni
Signed-off-by: Andrew Morton
Acked-by: Will Deacon [arm/arm64]
Acked-by: "Eric W. Biederman"
Cc: Aleksa Sarai
Cc: Alexander Shishkin
Cc: Al Viro
Cc: Andi Kleen
Cc: Andrew Morton
Cc: Andy Lutomirski
Cc: Arnaldo Carvalho de Melo
Cc: Arnd Bergmann
Cc: Benjamin Herrenschmidt
Cc: Bin Meng
Cc: Borislav Petkov
Cc: Brian Gerst
Cc: Catalin Marinas
Cc: chenzefeng
Cc: Christian Borntraeger
Cc: Christian Brauner
Cc: Chris Zankel
Cc: David Howells
Cc: David S. Miller
Cc: Diego Elio Pettenò
Cc: Dmitry Vyukov
Cc: Dominik Brodowski
Cc: Fenghua Yu
Cc: Geert Uytterhoeven
Cc: Heiko Carstens
Cc: Helge Deller
Cc: "H. Peter Anvin"
Cc: Ingo Molnar
Cc: Iurii Zaikin
Cc: Ivan Kokshaysky
Cc: James Bottomley
Cc: Jens Axboe
Cc: Jiri Olsa
Cc: Kars de Jong
Cc: Kees Cook
Cc: Krzysztof Kozlowski
Cc: Luis Chamberlain
Cc: Marco Elver
Cc: Mark Rutland
Cc: Martin K. Petersen
Cc: Masahiro Yamada
Cc: Matt Turner
Cc: Max Filippov
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Miklos Szeredi
Cc: Minchan Kim
Cc: Namhyung Kim
Cc: Naveen N. Rao
Cc: Nick Piggin
Cc: Oleg Nesterov
Cc: Olof Johansson
Cc: Paul Burton
Cc: "Paul E. McKenney"
Cc: Paul Mackerras
Cc: Peter Zijlstra (Intel)
Cc: Randy Dunlap
Cc: Ravi Bangoria
Cc: Richard Henderson
Cc: Rich Felker
Cc: Russell King
Cc: Sami Tolvanen
Cc: Sargun Dhillon
Cc: Stephen Rothwell
Cc: Sudeep Holla
Cc: Sven Schnelle
Cc: Thiago Jung Bauermann
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Vasily Gorbik
Cc: Vlastimil Babka
Cc: Yoshinori Sato
Cc: Zhou Yanjie
Link: http://lkml.kernel.org/r/20200616030734.87257-1-nixiaoming@huawei.com
Signed-off-by: Linus Torvalds
08 Aug, 2020
3 commits
-
Merge misc updates from Andrew Morton:
- a few MM hotfixes
- kthread, tools, scripts, ntfs and ocfs2
- some of MM
Subsystems affected by this patch series: kthread, tools, scripts, ntfs,
ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan,
debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore,
sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan).* emailed patches from Andrew Morton : (162 commits)
mm: vmscan: consistent update to pgrefill
mm/vmscan.c: fix typo
khugepaged: khugepaged_test_exit() check mmget_still_valid()
khugepaged: retract_page_tables() remember to test exit
khugepaged: collapse_pte_mapped_thp() protect the pmd lock
khugepaged: collapse_pte_mapped_thp() flush the right range
mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible
mm: thp: replace HTTP links with HTTPS ones
mm/page_alloc: fix memalloc_nocma_{save/restore} APIs
mm/page_alloc.c: skip setting nodemask when we are in interrupt
mm/page_alloc: fallbacks at most has 3 elements
mm/page_alloc: silence a KASAN false positive
mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask()
mm/page_alloc.c: simplify pageblock bitmap access
mm/page_alloc.c: extract the common part in pfn_to_bitidx()
mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits
mm/shuffle: remove dynamic reconfiguration
mm/memory_hotplug: document why shuffle_zone() is relevant
mm/page_alloc: remove nr_free_pagecache_pages()
mm: remove vm_total_pages
... -
Patch series "mm: cleanup usage of "
Most architectures have very similar versions of pXd_alloc_one() and
pXd_free_one() for intermediate levels of page table. These patches add
generic versions of these functions in and enable
use of the generic functions where appropriate.In addition, functions declared and defined in headers are
used mostly by core mm and early mm initialization in arch and there is no
actual reason to have the included all over the place.
The first patch in this series removes unneeded includes ofIn the end it didn't work out as neatly as I hoped and moving
pXd_alloc_track() definitions to would require
unnecessary changes to arches that have custom page table allocations, so
I've decided to move lib/ioremap.c to mm/ and make pgalloc-track.h local
to mm/.This patch (of 8):
In most cases header is required only for allocations of
page table memory. Most of the .c files that include that header do not
use symbols declared in and do not require that header.As for the other header files that used to include , it is
possible to move that include into the .c file that actually uses symbols
from and drop the include from the header file.The process was somewhat automated using
sed -i -E '/[
Signed-off-by: Andrew Morton
Reviewed-by: Pekka Enberg
Acked-by: Geert Uytterhoeven [m68k]
Cc: Abdul Haleem
Cc: Andy Lutomirski
Cc: Arnd Bergmann
Cc: Christophe Leroy
Cc: Joerg Roedel
Cc: Max Filippov
Cc: Peter Zijlstra
Cc: Satheesh Rajendran
Cc: Stafford Horne
Cc: Stephen Rothwell
Cc: Steven Rostedt
Cc: Joerg Roedel
Cc: Matthew Wilcox
Link: http://lkml.kernel.org/r/20200627143453.31835-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200627143453.31835-2-rppt@kernel.org
Signed-off-by: Linus Torvalds -
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()
...
07 Aug, 2020
1 commit
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Pull Xtensa updates from Max Filippov:
- add syscall audit support
- add seccomp filter support
- clean up make rules under arch/xtensa/boot
- fix state management for exclusive access opcodes
- fix build with PMU enabled
* tag 'xtensa-20200805' of git://github.com/jcmvbkbc/linux-xtensa:
xtensa: add missing exclusive access state management
xtensa: fix xtensa_pmu_setup prototype
xtensa: add boot subdirectories build artifacts to 'targets'
xtensa: add uImage and xipImage to targets
xtensa: move vmlinux.bin[.gz] to boot subdirectory
xtensa: initialize_mmu.h: fix a duplicated word
selftests/seccomp: add xtensa support
xtensa: add seccomp support
xtensa: expose syscall through user_pt_regs
xtensa: add audit support
05 Aug, 2020
2 commits
-
Pull close_range() implementation from Christian Brauner:
"This adds the close_range() syscall. It allows to efficiently close a
range of file descriptors up to all file descriptors of a calling
task.This is coordinated with the FreeBSD folks which have copied our
version of this syscall and in the meantime have already merged it in
April 2019:https://reviews.freebsd.org/D21627
https://svnweb.freebsd.org/base?view=revision&revision=359836The syscall originally came up in a discussion around the new mount
API and making new file descriptor types cloexec by default. During
this discussion, Al suggested the close_range() syscall.First, it helps to close all file descriptors of an exec()ing task.
This can be done safely via (quoting Al's example from [1] verbatim):/* that exec is sensitive */
unshare(CLONE_FILES);
/* we don't want anything past stderr here */
close_range(3, ~0U);
execve(....);The code snippet above is one way of working around the problem that
file descriptors are not cloexec by default. This is aggravated by the
fact that we can't just switch them over without massively regressing
userspace. For a whole class of programs having an in-kernel method of
closing all file descriptors is very helpful (e.g. demons, service
managers, programming language standard libraries, container managers
etc.).Second, it allows userspace to avoid implementing closing all file
descriptors by parsing through /proc//fd/* and calling close() on
each file descriptor and other hacks. From looking at various
large(ish) userspace code bases this or similar patterns are very
common in service managers, container runtimes, and programming
language runtimes/standard libraries such as Python or Rust.In addition, the syscall will also work for tasks that do not have
procfs mounted and on kernels that do not have procfs support compiled
in. In such situations the only way to make sure that all file
descriptors are closed is to call close() on each file descriptor up
to UINT_MAX or RLIMIT_NOFILE, OPEN_MAX trickery.Based on Linus' suggestion close_range() also comes with a new flag
CLOSE_RANGE_UNSHARE to more elegantly handle file descriptor dropping
right before exec. This would usually be expressed in the sequence:unshare(CLONE_FILES);
close_range(3, ~0U);as pointed out by Linus it might be desirable to have this be a part
of close_range() itself under a new flag CLOSE_RANGE_UNSHARE which
gets especially handy when we're closing all file descriptors above a
certain threshold.Test-suite as always included"
* tag 'close-range-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
tests: add CLOSE_RANGE_UNSHARE tests
close_range: add CLOSE_RANGE_UNSHARE
tests: add close_range() tests
arch: wire-up close_range()
open: add close_range() -
Pull fork cleanups from Christian Brauner:
"This is cleanup series from when we reworked a chunk of the process
creation paths in the kernel and switched to struct
{kernel_}clone_args.High-level this does two main things:
- Remove the double export of both do_fork() and _do_fork() where
do_fork() used the incosistent legacy clone calling convention.Now we only export _do_fork() which is based on struct
kernel_clone_args.- Remove the copy_thread_tls()/copy_thread() split making the
architecture specific HAVE_COYP_THREAD_TLS config option obsolete.This switches all remaining architectures to select
HAVE_COPY_THREAD_TLS and thus to the copy_thread_tls() calling
convention. The current split makes the process creation codepaths
more convoluted than they need to be. Each architecture has their own
copy_thread() function unless it selects HAVE_COPY_THREAD_TLS then it
has a copy_thread_tls() function.The split is not needed anymore nowadays, all architectures support
CLONE_SETTLS but quite a few of them never bothered to select
HAVE_COPY_THREAD_TLS and instead simply continued to use copy_thread()
and use the old calling convention. Removing this split cleans up the
process creation codepaths and paves the way for implementing clone3()
on such architectures since it requires the copy_thread_tls() calling
convention.After having made each architectures support copy_thread_tls() this
series simply renames that function back to copy_thread(). It also
switches all architectures that call do_fork() directly over to
_do_fork() and the struct kernel_clone_args calling convention. This
is a corollary of switching the architectures that did not yet support
it over to copy_thread_tls() since do_fork() is conditional on not
supporting copy_thread_tls() (Mostly because it lacks a separate
argument for tls which is trivial to fix but there's no need for this
function to exist.).The do_fork() removal is in itself already useful as it allows to to
remove the export of both do_fork() and _do_fork() we currently have
in favor of only _do_fork(). This has already been discussed back when
we added clone3(). The legacy clone() calling convention is - as is
probably well-known - somewhat odd:#
# ABI hall of shame
#
config CLONE_BACKWARDS
config CLONE_BACKWARDS2
config CLONE_BACKWARDS3that is aggravated by the fact that some architectures such as sparc
follow the CLONE_BACKWARDSx calling convention but don't really select
the corresponding config option since they call do_fork() directly.So do_fork() enforces a somewhat arbitrary calling convention in the
first place that doesn't really help the individual architectures that
deviate from it. They can thus simply be switched to _do_fork()
enforcing a single calling convention. (I really hope that any new
architectures will __not__ try to implement their own calling
conventions...)Most architectures already have made a similar switch (m68k comes to
mind).Overall this removes more code than it adds even with a good portion
of added comments. It simplifies a chunk of arch specific assembly
either by moving the code into C or by simply rewriting the assembly.Architectures that have been touched in non-trivial ways have all been
actually boot and stress tested: sparc and ia64 have been tested with
Debian 9 images. They are the two architectures which have been
touched the most. All non-trivial changes to architectures have seen
acks from the relevant maintainers. nios2 with a custom built
buildroot image. h8300 I couldn't get something bootable to test on
but the changes have been fairly automatic and I'm sure we'll hear
people yell if I broke something there.All other architectures that have been touched in trivial ways have
been compile tested for each single patch of the series via git rebase
-x "make ..." v5.8-rc2. arm{64} and x86{_64} have been boot tested
even though they have just been trivially touched (removal of the
HAVE_COPY_THREAD_TLS macro from their Kconfig) because well they are
basically "core architectures" and since it is trivial to get your
hands on a useable image"* tag 'fork-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
arch: rename copy_thread_tls() back to copy_thread()
arch: remove HAVE_COPY_THREAD_TLS
unicore: switch to copy_thread_tls()
sh: switch to copy_thread_tls()
nds32: switch to copy_thread_tls()
microblaze: switch to copy_thread_tls()
hexagon: switch to copy_thread_tls()
c6x: switch to copy_thread_tls()
alpha: switch to copy_thread_tls()
fork: remove do_fork()
h8300: select HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
nios2: enable HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
ia64: enable HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
sparc: unconditionally enable HAVE_COPY_THREAD_TLS
sparc: share process creation helpers between sparc and sparc64
sparc64: enable HAVE_COPY_THREAD_TLS
fork: fold legacy_clone_args_valid() into _do_fork()
01 Aug, 2020
2 commits
-
The result of the s32ex opcode is recorded in the ATOMCTL special
register and must be retrieved with the getex opcode. Context switch
between s32ex and getex may trash the ATOMCTL register and result in
duplicate update or missing update of the atomic variable.
Add atomctl8 field to the struct thread_info and use getex to swap
ATOMCTL bit 8 as a part of context switch.
Clear exclusive access monitor on kernel entry.Cc: stable@vger.kernel.org
Fixes: f7c34874f04a ("xtensa: add exclusive atomics support")
Signed-off-by: Max Filippov -
Fix the following build error in configurations with
CONFIG_XTENSA_VARIANT_HAVE_PERF_EVENTS=y:arch/xtensa/kernel/perf_event.c:420:29: error: passing argument 3 of
‘cpuhp_setup_state’ from incompatible pointer typeCc: stable@vger.kernel.org
Fixes: 25a77b55e74c ("xtensa/perf: Convert the hotplug notifier to state machine callbacks")
Signed-off-by: Max Filippov
28 Jul, 2020
4 commits
-
Add SECCOMP to xtensa Kconfig, select HAVE_ARCH_SECCOMP_FILTER, add
TIF_SECCOMP and call secure_computing from do_syscall_trace_enter.Signed-off-by: Max Filippov
-
Use one of the reserved slots in struct user_pt_regs to return syscall
number in the GPR regset. Update syscall number from the GPR regset only
when it's non-zero.Signed-off-by: Max Filippov
-
All bits needed for syscall audit are present on xtensa. Add
audit_syscall_entry and audit_syscall_exit calls and select
HAVE_ARCH_AUDITSYSCALL in Kconfig.Signed-off-by: Max Filippov
-
Signed-off-by: Al Viro
08 Jul, 2020
1 commit
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Use for_each_set_bit() instead of open-coding it to simplify the code.
Signed-off-by: Xu Wang
Message-Id:
Signed-off-by: Max Filippov
05 Jul, 2020
1 commit
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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 A
Acked-by: Stafford Horne
Acked-by: Greentime Hu
Acked-by: Geert Uytterhoeven A
Reviewed-by: Kees Cook
Signed-off-by: Christian Brauner
02 Jul, 2020
2 commits
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Increment *pos in the cpuinfo_op.next to fix the following warning
triggered by cat /proc/cpuinfo:seq_file: buggy .next function c_next did not update position index
Signed-off-by: Max Filippov
-
Building xtensa kernel with gcc-10 produces the following warnings:
arch/xtensa/kernel/xtensa_ksyms.c:90:15: warning: conflicting types
for built-in function ‘__sync_fetch_and_and_4’;
expected ‘unsigned int(volatile void *, unsigned int)’
[-Wbuiltin-declaration-mismatch]
arch/xtensa/kernel/xtensa_ksyms.c:96:15: warning: conflicting types
for built-in function ‘__sync_fetch_and_or_4’;
expected ‘unsigned int(volatile void *, unsigned int)’
[-Wbuiltin-declaration-mismatch]Fix declarations of these functions to avoid the warning.
Signed-off-by: Max Filippov
17 Jun, 2020
1 commit
-
This wires up the close_range() syscall into all arches at once.
Suggested-by: Arnd Bergmann
Signed-off-by: Christian Brauner
Reviewed-by: Oleg Nesterov
Acked-by: Arnd Bergmann
Acked-by: Michael Ellerman (powerpc)
Cc: Jann Horn
Cc: David Howells
Cc: Dmitry V. Levin
Cc: Linus Torvalds
Cc: Al Viro
Cc: Florian Weimer
Cc: linux-api@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: sparclinux@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
10 Jun, 2020
6 commits
-
The replacement of with made the include
of the latter in the middle of asm includes. Fix this up with the aid of
the below script and manual adjustments here and there.import sys
import reif len(sys.argv) is not 3:
print "USAGE: %s " % (sys.argv[0])
sys.exit(1)hdr_to_move="#include " % sys.argv[2]
moved = False
in_hdrs = Falsewith open(sys.argv[1], "r") as f:
lines = f.readlines()
for _line in lines:
line = _line.rstrip('
')
if line == hdr_to_move:
continue
if line.startswith("#include
Cc: Geert Uytterhoeven
Cc: Greentime Hu
Cc: Greg Ungerer
Cc: Guan Xuetao
Cc: Guo Ren
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Ley Foon Tan
Cc: Mark Salter
Cc: Matthew Wilcox
Cc: Matt Turner
Cc: Max Filippov
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Nick Hu
Cc: Paul Walmsley
Cc: Richard Weinberger
Cc: Rich Felker
Cc: Russell King
Cc: Stafford Horne
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Vincent Chen
Cc: Vineet Gupta
Cc: Will Deacon
Cc: Yoshinori Sato
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds -
The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.Signed-off-by: Mike Rapoport
Signed-off-by: Andrew Morton
Cc: Arnd Bergmann
Cc: Borislav Petkov
Cc: Brian Cain
Cc: Catalin Marinas
Cc: Chris Zankel
Cc: "David S. Miller"
Cc: Geert Uytterhoeven
Cc: Greentime Hu
Cc: Greg Ungerer
Cc: Guan Xuetao
Cc: Guo Ren
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Ley Foon Tan
Cc: Mark Salter
Cc: Matthew Wilcox
Cc: Matt Turner
Cc: Max Filippov
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Nick Hu
Cc: Paul Walmsley
Cc: Richard Weinberger
Cc: Rich Felker
Cc: Russell King
Cc: Stafford Horne
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Vincent Chen
Cc: Vineet Gupta
Cc: Will Deacon
Cc: Yoshinori Sato
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds -
Patch series "mm: consolidate definitions of page table accessors", v2.
The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once. For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.Most of these definitions are actually identical and typically it boils
down to, e.g.static inline unsigned long pmd_index(unsigned long address)
{
return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.This patch (of 12):
The linux/mm.h header includes to allow inlining of the
functions involving page table manipulations, e.g. pte_alloc() and
pmd_alloc(). So, there is no point to explicitly include
in the files that include .The include statements in such cases are remove with a simple loop:
for f in $(git grep -l "include ") ; do
sed -i -e '/include / d' $f
doneSigned-off-by: Mike Rapoport
Signed-off-by: Andrew Morton
Cc: Arnd Bergmann
Cc: Borislav Petkov
Cc: Brian Cain
Cc: Catalin Marinas
Cc: Chris Zankel
Cc: "David S. Miller"
Cc: Geert Uytterhoeven
Cc: Greentime Hu
Cc: Greg Ungerer
Cc: Guan Xuetao
Cc: Guo Ren
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Ley Foon Tan
Cc: Mark Salter
Cc: Matthew Wilcox
Cc: Matt Turner
Cc: Max Filippov
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Mike Rapoport
Cc: Nick Hu
Cc: Paul Walmsley
Cc: Richard Weinberger
Cc: Rich Felker
Cc: Russell King
Cc: Stafford Horne
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Tony Luck
Cc: Vincent Chen
Cc: Vineet Gupta
Cc: Will Deacon
Cc: Yoshinori Sato
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds -
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().Signed-off-by: Dmitry Safonov
Signed-off-by: Andrew Morton
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds -
Currently, the log-level of show_stack() depends on a platform
realization. It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).Furthermore, it forces the logic decision from user to an architecture
side. In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages. And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers. Also, it will consolidate
printings with headers.Introduce show_stack_loglvl(), that eventually will substitute
show_stack().[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u
Signed-off-by: Dmitry Safonov
Signed-off-by: Andrew Morton
Cc: Chris Zankel
Cc: Max Filippov
Link: http://lkml.kernel.org/r/20200418201944.482088-44-dima@arista.com
Signed-off-by: Linus Torvalds -
Currently, the log-level of show_stack() depends on a platform
realization. It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).Furthermore, it forces the logic decision from user to an architecture
side. In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages. And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers. Also, it will consolidate
printings with headers.Add log level argument to show_trace() as a preparation for introducing
show_stack_loglvl().[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u
[rppt@kernel.org: build fix]
Link: http://lkml.kernel.org/r/20200511194534.GA1018386@kernel.orgSigned-off-by: Dmitry Safonov
Signed-off-by: Andrew Morton
Cc: Chris Zankel
Cc: Max Filippov
Cc: Mike Rapoport
Link: http://lkml.kernel.org/r/20200418201944.482088-43-dima@arista.com
Signed-off-by: Linus Torvalds
04 Jun, 2020
1 commit
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Pull Xtensa updates from Max Filippov:
- fix __user annotations in asm/uaccess.h
- fix comments in entry.S
* tag 'xtensa-20200603' of git://github.com/jcmvbkbc/linux-xtensa:
xtensa: Fix spelling/grammar in comment
xtensa: add missing __user annotations to asm/uaccess.h
xtensa: fix error paths in __get_user_{check,size}
xtensa: fix type conversion in __get_user_size
xtensa: add missing __user annotations to __{get,put}_user_check
26 May, 2020
1 commit
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Change 'excpetion' to 'exception', 'handeled' to 'handled' and 'the the'
to 'the'.Signed-off-by: Chris Packham
Message-Id:
Signed-off-by: Max Filippov
14 May, 2020
1 commit
-
POSIX defines faccessat() as having a fourth "flags" argument, while the
linux syscall doesn't have it. Glibc tries to emulate AT_EACCESS and
AT_SYMLINK_NOFOLLOW, but AT_EACCESS emulation is broken.Add a new faccessat(2) syscall with the added flags argument and implement
both flags.The value of AT_EACCESS is defined in glibc headers to be the same as
AT_REMOVEDIR. Use this value for the kernel interface as well, together
with the explanatory comment.Also add AT_EMPTY_PATH support, which is not documented by POSIX, but can
be useful and is trivial to implement.Signed-off-by: Miklos Szeredi
11 Apr, 2020
1 commit
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Pull xtensa updates from Max Filippov:
- replace setup_irq() by request_irq()
- cosmetic fixes in xtensa Kconfig and boot/Makefile
* tag 'xtensa-20200410' of git://github.com/jcmvbkbc/linux-xtensa:
arch/xtensa: fix grammar in Kconfig help text
xtensa: remove meaningless export ccflags-y
xtensa: replace setup_irq() by request_irq()
08 Apr, 2020
1 commit
-
Generated files are also checked by sparse that's why add newline to
remove sparse (C=1) warning.The issue was found on Microblaze and reported like this:
./arch/microblaze/include/generated/uapi/asm/unistd_32.h:438:45: warning:
no newline at end of fileMips and PowerPC have it already but let's align with style used by m68k.
Signed-off-by: Michal Simek
Signed-off-by: Andrew Morton
Reviewed-by: Stefan Asserhall
Acked-by: Max Filippov (xtensa)
Cc: Arnd Bergmann
Cc: Max Filippov
Cc: Benjamin Herrenschmidt
Cc: Chris Zankel
Cc: David S. Miller
Cc: Fenghua Yu
Cc: Helge Deller
Cc: Ivan Kokshaysky
Cc: James Bottomley
Cc: Matt Turner
Cc: Michael Ellerman
Cc: Paul Burton
Cc: Paul Mackerras
Cc: Ralf Baechle
Cc: Rich Felker
Cc: Richard Henderson
Cc: Tony Luck
Cc: Yoshinori Sato
Link: http://lkml.kernel.org/r/4d32ab4e1fb2edb691d2e1687e8fb303c09fd023.1581504803.git.michal.simek@xilinx.com
Signed-off-by: Linus Torvalds
05 Apr, 2020
1 commit
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Pull dma-mapping updates from Christoph Hellwig:
- fix an integer overflow in the coherent pool (Kevin Grandemange)
- provide support for in-place uncached remapping and use that for
openrisc- fix the arm coherent allocator to take the bus limit into account
* tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping:
ARM/dma-mapping: merge __dma_supported into arm_dma_supported
ARM/dma-mapping: take the bus limit into account in __dma_alloc
ARM/dma-mapping: remove get_coherent_dma_mask
openrisc: use the generic in-place uncached DMA allocator
dma-direct: provide a arch_dma_clear_uncached hook
dma-direct: make uncached_kernel_address more general
dma-direct: consolidate the error handling in dma_direct_alloc_pages
dma-direct: remove the cached_kernel_address hook
dma-coherent: fix integer overflow in the reserved-memory dma allocation
25 Mar, 2020
1 commit
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Add SPDX License Identifier to all .gitignore files.
Signed-off-by: Masahiro Yamada
Signed-off-by: Greg Kroah-Hartman
16 Mar, 2020
2 commits
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Rename the symbol to arch_dma_set_uncached, and pass a size to it as
well as allow an error return. That will allow reusing this hook for
in-place pagetable remapping.As the in-place remap doesn't always require an explicit cache flush,
also detangle ARCH_HAS_DMA_PREP_COHERENT from ARCH_HAS_DMA_SET_UNCACHED.Signed-off-by: Christoph Hellwig
Reviewed-by: Robin Murphy -
dma-direct now finds the kernel address for coherent allocations based
on the dma address, so the cached_kernel_address hooks is unused and
can be removed entirely.Signed-off-by: Christoph Hellwig
Reviewed-by: Robin Murphy