/* Background. */
For a very long time, extending openat(2) with new features has been
incredibly frustrating. This stems from the fact that openat(2) is
possibly the most famous counter-example to the mantra "don't silently
accept garbage from userspace" -- it doesn't check whether unknown flags
are present[1].
This means that (generally) the addition of new flags to openat(2) has
been fraught with backwards-compatibility issues (O_TMPFILE has to be
defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
kernels gave errors, since it's insecure to silently ignore the
flag[2]). All new security-related flags therefore have a tough road to
being added to openat(2).
Userspace also has a hard time figuring out whether a particular flag is
supported on a particular kernel. While it is now possible with
contemporary kernels (thanks to [3]), older kernels will expose unknown
flag bits through fcntl(F_GETFL). Giving a clear -EINVAL during
openat(2) time matches modern syscall designs and is far more
fool-proof.
In addition, the newly-added path resolution restriction LOOKUP flags
(which we would like to expose to user-space) don't feel related to the
pre-existing O_* flag set -- they affect all components of path lookup.
We'd therefore like to add a new flag argument.
Adding a new syscall allows us to finally fix the flag-ignoring problem,
and we can make it extensible enough so that we will hopefully never
need an openat3(2).
/* Syscall Prototype. */
/*
* open_how is an extensible structure (similar in interface to
* clone3(2) or sched_setattr(2)). The size parameter must be set to
* sizeof(struct open_how), to allow for future extensions. All future
* extensions will be appended to open_how, with their zero value
* acting as a no-op default.
*/
struct open_how { /* ... */ };
int openat2(int dfd, const char *pathname,
struct open_how *how, size_t size);
/* Description. */
The initial version of 'struct open_how' contains the following fields:
flags
Used to specify openat(2)-style flags. However, any unknown flag
bits or otherwise incorrect flag combinations (like O_PATH|O_RDWR)
will result in -EINVAL. In addition, this field is 64-bits wide to
allow for more O_ flags than currently permitted with openat(2).
mode
The file mode for O_CREAT or O_TMPFILE.
Must be set to zero if flags does not contain O_CREAT or O_TMPFILE.
resolve
Restrict path resolution (in contrast to O_* flags they affect all
path components). The current set of flags are as follows (at the
moment, all of the RESOLVE_ flags are implemented as just passing
the corresponding LOOKUP_ flag).
RESOLVE_NO_XDEV => LOOKUP_NO_XDEV
RESOLVE_NO_SYMLINKS => LOOKUP_NO_SYMLINKS
RESOLVE_NO_MAGICLINKS => LOOKUP_NO_MAGICLINKS
RESOLVE_BENEATH => LOOKUP_BENEATH
RESOLVE_IN_ROOT => LOOKUP_IN_ROOT
open_how does not contain an embedded size field, because it is of
little benefit (userspace can figure out the kernel open_how size at
runtime fairly easily without it). It also only contains u64s (even
though ->mode arguably should be a u16) to avoid having padding fields
which are never used in the future.
Note that as a result of the new how->flags handling, O_PATH|O_TMPFILE
is no longer permitted for openat(2). As far as I can tell, this has
always been a bug and appears to not be used by userspace (and I've not
seen any problems on my machines by disallowing it). If it turns out
this breaks something, we can special-case it and only permit it for
openat(2) but not openat2(2).
After input from Florian Weimer, the new open_how and flag definitions
are inside a separate header from uapi/linux/fcntl.h, to avoid problems
that glibc has with importing that header.
/* Testing. */
In a follow-up patch there are over 200 selftests which ensure that this
syscall has the correct semantics and will correctly handle several
attack scenarios.
In addition, I've written a userspace library[4] which provides
convenient wrappers around openat2(RESOLVE_IN_ROOT) (this is necessary
because no other syscalls support RESOLVE_IN_ROOT, and thus lots of care
must be taken when using RESOLVE_IN_ROOT'd file descriptors with other
syscalls). During the development of this patch, I've run numerous
verification tests using libpathrs (showing that the API is reasonably
usable by userspace).
/* Future Work. */
Additional RESOLVE_ flags have been suggested during the review period.
These can be easily implemented separately (such as blocking auto-mount
during resolution).
Furthermore, there are some other proposed changes to the openat(2)
interface (the most obvious example is magic-link hardening[5]) which
would be a good opportunity to add a way for userspace to restrict how
O_PATH file descriptors can be re-opened.
Another possible avenue of future work would be some kind of
CHECK_FIELDS[6] flag which causes the kernel to indicate to userspace
which openat2(2) flags and fields are supported by the current kernel
(to avoid userspace having to go through several guesses to figure it
out).
[1]: https://lwn.net/Articles/588444/
[2]: https://lore.kernel.org/lkml/CA+55aFyyxJL1LyXZeBsf2ypriraj5ut1XkNDsunRBqgVjZU_6Q@mail.gmail.com
[3]: commit 629e014bb8 ("fs: completely ignore unknown open flags")
[4]: https://sourceware.org/bugzilla/show_bug.cgi?id=17523
[5]: https://lore.kernel.org/lkml/20190930183316.10190-2-cyphar@cyphar.com/
[6]: https://youtu.be/ggD-eb3yPVs
Suggested-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull parisc fixes from Helge Deller:
"A boot crash fix by Mike Rapoport and a printk fix by Krzysztof
Kozlowski"
* 'parisc-5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: fix map_pages() to actually populate upper directory
parisc: Use proper printk format for resource_size_t
The commit d96885e277 ("parisc: use pgtable-nopXd instead of
4level-fixup") converted PA-RISC to use folded page tables, but it missed
the conversion of pgd_populate() to pud_populate() in maps_pages()
function. This caused the upper page table directory to remain empty and
the system would crash as a result.
Using pud_populate() that actually populates the page table instead of
dummy pgd_populate() fixes the issue.
Fixes: d96885e277 ("parisc: use pgtable-nopXd instead of 4level-fixup")
Reported-by: Meelis Roos <mroos@linux.ee>
Reported-by: Jeroen Roovers <jer@gentoo.org>
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Tested-by: Jeroen Roovers <jer@gentoo.org>
Tested-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
resource_size_t should be printed with its own size-independent format
to fix warnings when compiling on 64-bit platform (e.g. with
COMPILE_TEST):
arch/parisc/kernel/drivers.c: In function 'print_parisc_device':
arch/parisc/kernel/drivers.c:892:9: warning:
format '%p' expects argument of type 'void *',
but argument 4 has type 'resource_size_t {aka unsigned int}' [-Wformat=]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Fix this compiler warning:
kernel/debug/debug_core.c: In function ‘kgdb_cpu_enter’:
arch/parisc/include/asm/cmpxchg.h:48:3: warning: value computed is not used [-Wunused-value]
48 | ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
arch/parisc/include/asm/atomic.h:78:30: note: in expansion of macro ‘xchg’
78 | #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
| ^~~~
kernel/debug/debug_core.c:596:4: note: in expansion of macro ‘atomic_xchg’
596 | atomic_xchg(&kgdb_active, cpu);
| ^~~~~~~~~~~
Signed-off-by: Helge Deller <deller@gmx.de>
Switch page deallocation table (pdt) driver to use pfn instead of a page
pointer in soft_offline_page().
Fixes: feec24a613 ("mm, soft-offline: convert parameter to pfn")
Signed-off-by: Helge Deller <deller@gmx.de>
compilation failed with:
MODPOST vmlinux.o
WARNING: vmlinux.o(.text.unlikely+0xa0c): Section mismatch in reference from the function walk_lower_bus() to the function .init.text:walk_native_bus()
The function walk_lower_bus() references
the function __init walk_native_bus().
This is often because walk_lower_bus lacks a __init
annotation or the annotation of walk_native_bus is wrong.
FATAL: modpost: Section mismatches detected.
Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.
make[2]: *** [/home/svens/linux/parisc-linux/src/scripts/Makefile.modpost:64: __modpost] Error 1
make[1]: *** [/home/svens/linux/parisc-linux/src/Makefile:1077: vmlinux] Error 2
make[1]: Leaving directory '/home/svens/linux/parisc-linux/build'
make: *** [Makefile:179: sub-make] Error 2
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Fix compilation when the CONFIG_KEXEC_FILE=y and
CONFIG_KEXEC=n.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
parisc has two or three levels of page tables and can use appropriate
pgtable-nopXd and folding of the upper layers.
Replace usage of include/asm-generic/4level-fixup.h and explicit
definitions of __PAGETABLE_PxD_FOLDED in parisc with
include/asm-generic/pgtable-nopmd.h for two-level configurations and
with include/asm-generic/pgtable-nopud.h for three-lelve configurations
and adjust page table manipulation macros and functions accordingly.
Link: http://lkml.kernel.org/r/1572938135-31886-9-git-send-email-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Rosin <peda@axentia.se>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Sam Creasey <sammy@sammy.net>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Userspace cannot compile <asm/sembuf.h> due to some missing type
definitions. For example, building it for x86 fails as follows:
CC usr/include/asm/sembuf.h.s
In file included from <command-line>:32:0:
usr/include/asm/sembuf.h:17:20: error: field `sem_perm' has incomplete type
struct ipc64_perm sem_perm; /* permissions .. see ipc.h */
^~~~~~~~
usr/include/asm/sembuf.h:24:2: error: unknown type name `__kernel_time_t'
__kernel_time_t sem_otime; /* last semop time */
^~~~~~~~~~~~~~~
usr/include/asm/sembuf.h:25:2: error: unknown type name `__kernel_ulong_t'
__kernel_ulong_t __unused1;
^~~~~~~~~~~~~~~~
usr/include/asm/sembuf.h:26:2: error: unknown type name `__kernel_time_t'
__kernel_time_t sem_ctime; /* last change time */
^~~~~~~~~~~~~~~
usr/include/asm/sembuf.h:27:2: error: unknown type name `__kernel_ulong_t'
__kernel_ulong_t __unused2;
^~~~~~~~~~~~~~~~
usr/include/asm/sembuf.h:29:2: error: unknown type name `__kernel_ulong_t'
__kernel_ulong_t sem_nsems; /* no. of semaphores in array */
^~~~~~~~~~~~~~~~
usr/include/asm/sembuf.h:30:2: error: unknown type name `__kernel_ulong_t'
__kernel_ulong_t __unused3;
^~~~~~~~~~~~~~~~
usr/include/asm/sembuf.h:31:2: error: unknown type name `__kernel_ulong_t'
__kernel_ulong_t __unused4;
^~~~~~~~~~~~~~~~
It is just a matter of missing include directive.
Include <asm/ipcbuf.h> to make it self-contained, and add it to
the compile-test coverage.
Link: http://lkml.kernel.org/r/20191030063855.9989-3-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Userspace cannot compile <asm/msgbuf.h> due to some missing type
definitions. For example, building it for x86 fails as follows:
CC usr/include/asm/msgbuf.h.s
In file included from usr/include/asm/msgbuf.h:6:0,
from <command-line>:32:
usr/include/asm-generic/msgbuf.h:25:20: error: field `msg_perm' has incomplete type
struct ipc64_perm msg_perm;
^~~~~~~~
usr/include/asm-generic/msgbuf.h:27:2: error: unknown type name `__kernel_time_t'
__kernel_time_t msg_stime; /* last msgsnd time */
^~~~~~~~~~~~~~~
usr/include/asm-generic/msgbuf.h:28:2: error: unknown type name `__kernel_time_t'
__kernel_time_t msg_rtime; /* last msgrcv time */
^~~~~~~~~~~~~~~
usr/include/asm-generic/msgbuf.h:29:2: error: unknown type name `__kernel_time_t'
__kernel_time_t msg_ctime; /* last change time */
^~~~~~~~~~~~~~~
usr/include/asm-generic/msgbuf.h:41:2: error: unknown type name `__kernel_pid_t'
__kernel_pid_t msg_lspid; /* pid of last msgsnd */
^~~~~~~~~~~~~~
usr/include/asm-generic/msgbuf.h:42:2: error: unknown type name `__kernel_pid_t'
__kernel_pid_t msg_lrpid; /* last receive pid */
^~~~~~~~~~~~~~
It is just a matter of missing include directive.
Include <asm/ipcbuf.h> to make it self-contained, and add it to
the compile-test coverage.
Link: http://lkml.kernel.org/r/20191030063855.9989-2-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a series of cleanups for the y2038 work, mostly intended
for namespace cleaning: the kernel defines the traditional
time_t, timeval and timespec types that often lead to y2038-unsafe
code. Even though the unsafe usage is mostly gone from the kernel,
having the types and associated functions around means that we
can still grow new users, and that we may be missing conversions
to safe types that actually matter.
There are still a number of driver specific patches needed to
get the last users of these types removed, those have been
submitted to the respective maintainers.
Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground
Pull y2038 cleanups from Arnd Bergmann:
"y2038 syscall implementation cleanups
This is a series of cleanups for the y2038 work, mostly intended for
namespace cleaning: the kernel defines the traditional time_t, timeval
and timespec types that often lead to y2038-unsafe code. Even though
the unsafe usage is mostly gone from the kernel, having the types and
associated functions around means that we can still grow new users,
and that we may be missing conversions to safe types that actually
matter.
There are still a number of driver specific patches needed to get the
last users of these types removed, those have been submitted to the
respective maintainers"
Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/
* tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (26 commits)
y2038: alarm: fix half-second cut-off
y2038: ipc: fix x32 ABI breakage
y2038: fix typo in powerpc vdso "LOPART"
y2038: allow disabling time32 system calls
y2038: itimer: change implementation to timespec64
y2038: move itimer reset into itimer.c
y2038: use compat_{get,set}_itimer on alpha
y2038: itimer: compat handling to itimer.c
y2038: time: avoid timespec usage in settimeofday()
y2038: timerfd: Use timespec64 internally
y2038: elfcore: Use __kernel_old_timeval for process times
y2038: make ns_to_compat_timeval use __kernel_old_timeval
y2038: socket: use __kernel_old_timespec instead of timespec
y2038: socket: remove timespec reference in timestamping
y2038: syscalls: change remaining timeval to __kernel_old_timeval
y2038: rusage: use __kernel_old_timeval
y2038: uapi: change __kernel_time_t to __kernel_old_time_t
y2038: stat: avoid 'time_t' in 'struct stat'
y2038: ipc: remove __kernel_time_t reference from headers
y2038: vdso: powerpc: avoid timespec references
...
Pull sysctl system call removal from Eric Biederman:
"As far as I can tell we have reached the point where no one enables
the sysctl system call anymore. It still is enabled in a few
defconfigs but they are mostly the rarely used one and in asking
people about that it was more cut & paste enabled than anything else.
This is single commit that just deletes code. Leaving just enough code
so that the deprecated sysctl warning continues to be printed. If my
analysis turns out to be wrong and someone actually cares it will be
easy to revert this commit and have the system call again.
There was one new xtensa defconfig in linux-next that enabled the
system call this cycle and when asked about it the maintainer of the
code replied that it was not enabled on purpose. As of today's
linux-next tree that defconfig no longer enables the system call.
What we saw in the review discussion was that if we go a step farther
than my patch and mess with uapi headers there are pieces of code that
won't compile, but nothing minds the system call actually disappearing
from the kernel"
Link: https://lore.kernel.org/lkml/201910011140.EA0181F13@keescook/
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
sysctl: Remove the sysctl system call
Pull parisc updates from Helge Deller:
"Just trivial small updates: An assembler register optimization in the
inlined networking checksum functions, a compiler warning fix and
don't unneccesary print a runtime warning on machines which wouldn't
be affected anyway"
* 'parisc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Avoid spurious inequivalent alias kernel error messages
kexec: Fix pointer-to-int-cast warnings
parisc: Do not hardcode registers in checksum functions
- improve dma-debug scalability (Eric Dumazet)
- tiny dma-debug cleanup (Dan Carpenter)
- check for vmap memory in dma_map_single (Kees Cook)
- check for dma_addr_t overflows in dma-direct when using
DMA offsets (Nicolas Saenz Julienne)
- switch the x86 sta2x11 SOC to use more generic DMA code
(Nicolas Saenz Julienne)
- fix arm-nommu dma-ranges handling (Vladimir Murzin)
- use __initdata in CMA (Shyam Saini)
- replace the bus dma mask with a limit (Nicolas Saenz Julienne)
- merge the remapping helpers into the main dma-direct flow (me)
- switch xtensa to the generic dma remap handling (me)
- various cleanups around dma_capable (me)
- remove unused dev arguments to various dma-noncoherent helpers (me)
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Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- improve dma-debug scalability (Eric Dumazet)
- tiny dma-debug cleanup (Dan Carpenter)
- check for vmap memory in dma_map_single (Kees Cook)
- check for dma_addr_t overflows in dma-direct when using DMA offsets
(Nicolas Saenz Julienne)
- switch the x86 sta2x11 SOC to use more generic DMA code (Nicolas
Saenz Julienne)
- fix arm-nommu dma-ranges handling (Vladimir Murzin)
- use __initdata in CMA (Shyam Saini)
- replace the bus dma mask with a limit (Nicolas Saenz Julienne)
- merge the remapping helpers into the main dma-direct flow (me)
- switch xtensa to the generic dma remap handling (me)
- various cleanups around dma_capable (me)
- remove unused dev arguments to various dma-noncoherent helpers (me)
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux:
* tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping: (22 commits)
dma-mapping: treat dev->bus_dma_mask as a DMA limit
dma-direct: exclude dma_direct_map_resource from the min_low_pfn check
dma-direct: don't check swiotlb=force in dma_direct_map_resource
dma-debug: clean up put_hash_bucket()
powerpc: remove support for NULL dev in __phys_to_dma / __dma_to_phys
dma-direct: avoid a forward declaration for phys_to_dma
dma-direct: unify the dma_capable definitions
dma-mapping: drop the dev argument to arch_sync_dma_for_*
x86/PCI: sta2x11: use default DMA address translation
dma-direct: check for overflows on 32 bit DMA addresses
dma-debug: increase HASH_SIZE
dma-debug: reorder struct dma_debug_entry fields
xtensa: use the generic uncached segment support
dma-mapping: merge the generic remapping helpers into dma-direct
dma-direct: provide mmap and get_sgtable method overrides
dma-direct: remove the dma_handle argument to __dma_direct_alloc_pages
dma-direct: remove __dma_direct_free_pages
usb: core: Remove redundant vmap checks
kernel: dma-contiguous: mark CMA parameters __initdata/__initconst
dma-debug: add a schedule point in debug_dma_dump_mappings()
...
- clean up various obsolete ioremap and iounmap variants
- add a new generic ioremap implementation and switch csky, nds32 and
riscv over to it
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Merge tag 'ioremap-5.5' of git://git.infradead.org/users/hch/ioremap
Pull generic ioremap support from Christoph Hellwig:
"This adds the remaining bits for an entirely generic ioremap and
iounmap to lib/ioremap.c. To facilitate that, it cleans up the giant
mess of weird ioremap variants we had with no users outside the arch
code.
For now just the three newest ports use the code, but there is more
than a handful others that can be converted without too much work.
Summary:
- clean up various obsolete ioremap and iounmap variants
- add a new generic ioremap implementation and switch csky, nds32 and
riscv over to it"
* tag 'ioremap-5.5' of git://git.infradead.org/users/hch/ioremap: (21 commits)
nds32: use generic ioremap
csky: use generic ioremap
csky: remove ioremap_cache
riscv: use the generic ioremap code
lib: provide a simple generic ioremap implementation
sh: remove __iounmap
nios2: remove __iounmap
hexagon: remove __iounmap
m68k: rename __iounmap and mark it static
arch: rely on asm-generic/io.h for default ioremap_* definitions
asm-generic: don't provide ioremap for CONFIG_MMU
asm-generic: ioremap_uc should behave the same with and without MMU
xtensa: clean up ioremap
x86: Clean up ioremap()
parisc: remove __ioremap
nios2: remove __ioremap
alpha: remove the unused __ioremap wrapper
hexagon: clean up ioremap
ia64: rename ioremap_nocache to ioremap_uc
unicore32: remove ioremap_cached
...
This system call has been deprecated almost since it was introduced, and
in a survey of the linux distributions I can no longer find any of them
that enable CONFIG_SYSCTL_SYSCALL. The only indication that I can find
that anyone might care is that a few of the defconfigs in the kernel
enable CONFIG_SYSCTL_SYSCALL. However this appears in only 31 of 414
defconfigs in the kernel, so I suspect this symbols presence is simply
because it is harmless to include rather than because it is necessary.
As there appear to be no users of the sysctl system call, remove the
code. As this removes one of the few uses of the internal kernel mount
of proc I hope this allows for even more simplifications of the proc
filesystem.
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Anders Berg <anders.berg@lsi.com>
Cc: Apelete Seketeli <apelete@seketeli.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chee Nouk Phoon <cnphoon@altera.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Christian Ruppert <christian.ruppert@abilis.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Harvey Hunt <harvey.hunt@imgtec.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hongliang Tao <taohl@lemote.com>
Cc: Hua Yan <yanh@lemote.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Jun Nie <jun.nie@linaro.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Kevin Wells <kevin.wells@nxp.com>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Roland Stigge <stigge@antcom.de>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Scott Telford <stelford@cadence.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Tanmay Inamdar <tinamdar@apm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull x86 asm updates from Ingo Molnar:
"The main changes in this cycle were:
- Cross-arch changes to move the linker sections for NOTES and
EXCEPTION_TABLE into the RO_DATA area, where they belong on most
architectures. (Kees Cook)
- Switch the x86 linker fill byte from x90 (NOP) to 0xcc (INT3), to
trap jumps into the middle of those padding areas instead of
sliding execution. (Kees Cook)
- A thorough cleanup of symbol definitions within x86 assembler code.
The rather randomly named macros got streamlined around a
(hopefully) straightforward naming scheme:
SYM_START(name, linkage, align...)
SYM_END(name, sym_type)
SYM_FUNC_START(name)
SYM_FUNC_END(name)
SYM_CODE_START(name)
SYM_CODE_END(name)
SYM_DATA_START(name)
SYM_DATA_END(name)
etc - with about three times of these basic primitives with some
label, local symbol or attribute variant, expressed via postfixes.
No change in functionality intended. (Jiri Slaby)
- Misc other changes, cleanups and smaller fixes"
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
x86/entry/64: Remove pointless jump in paranoid_exit
x86/entry/32: Remove unused resume_userspace label
x86/build/vdso: Remove meaningless CFLAGS_REMOVE_*.o
m68k: Convert missed RODATA to RO_DATA
x86/vmlinux: Use INT3 instead of NOP for linker fill bytes
x86/mm: Report actual image regions in /proc/iomem
x86/mm: Report which part of kernel image is freed
x86/mm: Remove redundant address-of operators on addresses
xtensa: Move EXCEPTION_TABLE to RO_DATA segment
powerpc: Move EXCEPTION_TABLE to RO_DATA segment
parisc: Move EXCEPTION_TABLE to RO_DATA segment
microblaze: Move EXCEPTION_TABLE to RO_DATA segment
ia64: Move EXCEPTION_TABLE to RO_DATA segment
h8300: Move EXCEPTION_TABLE to RO_DATA segment
c6x: Move EXCEPTION_TABLE to RO_DATA segment
arm64: Move EXCEPTION_TABLE to RO_DATA segment
alpha: Move EXCEPTION_TABLE to RO_DATA segment
x86/vmlinux: Move EXCEPTION_TABLE to RO_DATA segment
x86/vmlinux: Actually use _etext for the end of the text segment
vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA
...
- On ARMv8 CPUs without hardware updates of the access flag, avoid
failing cow_user_page() on PFN mappings if the pte is old. The patches
introduce an arch_faults_on_old_pte() macro, defined as false on x86.
When true, cow_user_page() makes the pte young before attempting
__copy_from_user_inatomic().
- Covert the synchronous exception handling paths in
arch/arm64/kernel/entry.S to C.
- FTRACE_WITH_REGS support for arm64.
- ZONE_DMA re-introduced on arm64 to support Raspberry Pi 4
- Several kselftest cases specific to arm64, together with a MAINTAINERS
update for these files (moved to the ARM64 PORT entry).
- Workaround for a Neoverse-N1 erratum where the CPU may fetch stale
instructions under certain conditions.
- Workaround for Cortex-A57 and A72 errata where the CPU may
speculatively execute an AT instruction and associate a VMID with the
wrong guest page tables (corrupting the TLB).
- Perf updates for arm64: additional PMU topologies on HiSilicon
platforms, support for CCN-512 interconnect, AXI ID filtering in the
IMX8 DDR PMU, support for the CCPI2 uncore PMU in ThunderX2.
- GICv3 optimisation to avoid a heavy barrier when accessing the
ICC_PMR_EL1 register.
- ELF HWCAP documentation updates and clean-up.
- SMC calling convention conduit code clean-up.
- KASLR diagnostics printed during boot
- NVIDIA Carmel CPU added to the KPTI whitelist
- Some arm64 mm clean-ups: use generic free_initrd_mem(), remove stale
macro, simplify calculation in __create_pgd_mapping(), typos.
- Kconfig clean-ups: CMDLINE_FORCE to depend on CMDLINE, choice for
endinanness to help with allmodconfig.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
"Apart from the arm64-specific bits (core arch and perf, new arm64
selftests), it touches the generic cow_user_page() (reviewed by
Kirill) together with a macro for x86 to preserve the existing
behaviour on this architecture.
Summary:
- On ARMv8 CPUs without hardware updates of the access flag, avoid
failing cow_user_page() on PFN mappings if the pte is old. The
patches introduce an arch_faults_on_old_pte() macro, defined as
false on x86. When true, cow_user_page() makes the pte young before
attempting __copy_from_user_inatomic().
- Covert the synchronous exception handling paths in
arch/arm64/kernel/entry.S to C.
- FTRACE_WITH_REGS support for arm64.
- ZONE_DMA re-introduced on arm64 to support Raspberry Pi 4
- Several kselftest cases specific to arm64, together with a
MAINTAINERS update for these files (moved to the ARM64 PORT entry).
- Workaround for a Neoverse-N1 erratum where the CPU may fetch stale
instructions under certain conditions.
- Workaround for Cortex-A57 and A72 errata where the CPU may
speculatively execute an AT instruction and associate a VMID with
the wrong guest page tables (corrupting the TLB).
- Perf updates for arm64: additional PMU topologies on HiSilicon
platforms, support for CCN-512 interconnect, AXI ID filtering in
the IMX8 DDR PMU, support for the CCPI2 uncore PMU in ThunderX2.
- GICv3 optimisation to avoid a heavy barrier when accessing the
ICC_PMR_EL1 register.
- ELF HWCAP documentation updates and clean-up.
- SMC calling convention conduit code clean-up.
- KASLR diagnostics printed during boot
- NVIDIA Carmel CPU added to the KPTI whitelist
- Some arm64 mm clean-ups: use generic free_initrd_mem(), remove
stale macro, simplify calculation in __create_pgd_mapping(), typos.
- Kconfig clean-ups: CMDLINE_FORCE to depend on CMDLINE, choice for
endinanness to help with allmodconfig"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits)
arm64: Kconfig: add a choice for endianness
kselftest: arm64: fix spelling mistake "contiguos" -> "contiguous"
arm64: Kconfig: make CMDLINE_FORCE depend on CMDLINE
MAINTAINERS: Add arm64 selftests to the ARM64 PORT entry
arm64: kaslr: Check command line before looking for a seed
arm64: kaslr: Announce KASLR status on boot
kselftest: arm64: fake_sigreturn_misaligned_sp
kselftest: arm64: fake_sigreturn_bad_size
kselftest: arm64: fake_sigreturn_duplicated_fpsimd
kselftest: arm64: fake_sigreturn_missing_fpsimd
kselftest: arm64: fake_sigreturn_bad_size_for_magic0
kselftest: arm64: fake_sigreturn_bad_magic
kselftest: arm64: add helper get_current_context
kselftest: arm64: extend test_init functionalities
kselftest: arm64: mangle_pstate_invalid_mode_el[123][ht]
kselftest: arm64: mangle_pstate_invalid_daif_bits
kselftest: arm64: mangle_pstate_invalid_compat_toggle and common utils
kselftest: arm64: extend toplevel skeleton Makefile
drivers/perf: hisi: update the sccl_id/ccl_id for certain HiSilicon platform
arm64: mm: reserve CMA and crashkernel in ZONE_DMA32
...
These are pure cache maintainance routines, so drop the unused
struct device argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
There are two structures based on time_t that conflict between libc and
kernel: timeval and timespec. Both are now renamed to __kernel_old_timeval
and __kernel_old_timespec.
For time_t, the old typedef is still __kernel_time_t. There is nothing
wrong with that name, but it would be nice to not use that going forward
as this type is used almost only in deprecated interfaces because of
the y2038 overflow.
In the IPC headers (msgbuf.h, sembuf.h, shmbuf.h), __kernel_time_t is only
used for the 64-bit variants, which are not deprecated.
Change these to a plain 'long', which is the same type as __kernel_time_t
on all 64-bit architectures anyway, to reduce the number of users of the
old type.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
__ioremap is always called with the _PAGE_NO_CACHE, so fold the whole
thing and rename it to ioremap.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Helge Deller <deller@gmx.de>
When using patchable-function-entry, the compiler will record the
callsites into a section named "__patchable_function_entries" rather
than "__mcount_loc". Let's abstract this difference behind a new
FTRACE_CALLSITE_SECTION, so that architectures don't have to handle this
explicitly (e.g. with custom module linker scripts).
As parisc currently handles this explicitly, it is fixed up accordingly,
with its custom linker script removed. Since FTRACE_CALLSITE_SECTION is
only defined when DYNAMIC_FTRACE is selected, the parisc module loading
code is updated to only use the definition in that case. When
DYNAMIC_FTRACE is not selected, modules shouldn't have this section, so
this removes some redundant work in that case.
To make sure that this is keep up-to-date for modules and the main
kernel, a comment is added to vmlinux.lds.h, with the existing ifdeffery
simplified for legibility.
I built parisc generic-{32,64}bit_defconfig with DYNAMIC_FTRACE enabled,
and verified that the section made it into the .ko files for modules.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Helge Deller <deller@gmx.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Torsten Duwe <duwe@suse.de>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Tested-by: Sven Schnelle <svens@stackframe.org>
Tested-by: Torsten Duwe <duwe@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: linux-parisc@vger.kernel.org
This patch changes flush_dcache_page() to only print inequivalent alias error
messages on systems that require coherency. Inequivalent aliases can occur on
systems that don't require coherency and this can cause spurious messages.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
The current code in ftrace_regs_caller() doesn't assign
%r3 to contain the address of the current frame. This
is hidden if the kernel is compiled with FRAME_POINTER,
but without it just crashes because it tries to dereference
an arbitrary address. Fix this by always setting %r3 to the
current stack frame.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Sven noticed that calling ioremap() and iounmap() multiple times leads
to a vmap memory leak:
vmap allocation for size 4198400 failed:
use vmalloc=<size> to increase size
It seems we missed calling vunmap() in iounmap().
Signed-off-by: Helge Deller <deller@gmx.de>
Noticed-by: Sven Schnelle <svens@stackframe.org>
Cc: <stable@vger.kernel.org> # v3.16+
Do not hardcode processor registers r19 to r22 as scratch registers.
Instead let the compiler decide, which may give better optimization
results when the functions get inlined.
Signed-off-by: Helge Deller <deller@gmx.de>
When a process expects no accesses to a certain memory range for a long
time, it could hint kernel that the pages can be reclaimed instantly but
data should be preserved for future use. This could reduce workingset
eviction so it ends up increasing performance.
This patch introduces the new MADV_PAGEOUT hint to madvise(2) syscall.
MADV_PAGEOUT can be used by a process to mark a memory range as not
expected to be used for a long time so that kernel reclaims *any LRU*
pages instantly. The hint can help kernel in deciding which pages to
evict proactively.
A note: It doesn't apply SWAP_CLUSTER_MAX LRU page isolation limit
intentionally because it's automatically bounded by PMD size. If PMD
size(e.g., 256) makes some trouble, we could fix it later by limit it to
SWAP_CLUSTER_MAX[1].
- man-page material
MADV_PAGEOUT (since Linux x.x)
Do not expect access in the near future so pages in the specified
regions could be reclaimed instantly regardless of memory pressure.
Thus, access in the range after successful operation could cause
major page fault but never lose the up-to-date contents unlike
MADV_DONTNEED. Pages belonging to a shared mapping are only processed
if a write access is allowed for the calling process.
MADV_PAGEOUT cannot be applied to locked pages, Huge TLB pages, or
VM_PFNMAP pages.
[1] https://lore.kernel.org/lkml/20190710194719.GS29695@dhcp22.suse.cz/
[minchan@kernel.org: clear PG_active on MADV_PAGEOUT]
Link: http://lkml.kernel.org/r/20190802200643.GA181880@google.com
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-5-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Colascione <dancol@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tim Murray <timmurray@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Introduce MADV_COLD and MADV_PAGEOUT", v7.
- Background
The Android terminology used for forking a new process and starting an app
from scratch is a cold start, while resuming an existing app is a hot
start. While we continually try to improve the performance of cold
starts, hot starts will always be significantly less power hungry as well
as faster so we are trying to make hot start more likely than cold start.
To increase hot start, Android userspace manages the order that apps
should be killed in a process called ActivityManagerService.
ActivityManagerService tracks every Android app or service that the user
could be interacting with at any time and translates that into a ranked
list for lmkd(low memory killer daemon). They are likely to be killed by
lmkd if the system has to reclaim memory. In that sense they are similar
to entries in any other cache. Those apps are kept alive for
opportunistic performance improvements but those performance improvements
will vary based on the memory requirements of individual workloads.
- Problem
Naturally, cached apps were dominant consumers of memory on the system.
However, they were not significant consumers of swap even though they are
good candidate for swap. Under investigation, swapping out only begins
once the low zone watermark is hit and kswapd wakes up, but the overall
allocation rate in the system might trip lmkd thresholds and cause a
cached process to be killed(we measured performance swapping out vs.
zapping the memory by killing a process. Unsurprisingly, zapping is 10x
times faster even though we use zram which is much faster than real
storage) so kill from lmkd will often satisfy the high zone watermark,
resulting in very few pages actually being moved to swap.
- Approach
The approach we chose was to use a new interface to allow userspace to
proactively reclaim entire processes by leveraging platform information.
This allowed us to bypass the inaccuracy of the kernel’s LRUs for pages
that are known to be cold from userspace and to avoid races with lmkd by
reclaiming apps as soon as they entered the cached state. Additionally,
it could provide many chances for platform to use much information to
optimize memory efficiency.
To achieve the goal, the patchset introduce two new options for madvise.
One is MADV_COLD which will deactivate activated pages and the other is
MADV_PAGEOUT which will reclaim private pages instantly. These new
options complement MADV_DONTNEED and MADV_FREE by adding non-destructive
ways to gain some free memory space. MADV_PAGEOUT is similar to
MADV_DONTNEED in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed immediately; MADV_COLD is similar
to MADV_FREE in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed when memory pressure rises.
This patch (of 5):
When a process expects no accesses to a certain memory range, it could
give a hint to kernel that the pages can be reclaimed when memory pressure
happens but data should be preserved for future use. This could reduce
workingset eviction so it ends up increasing performance.
This patch introduces the new MADV_COLD hint to madvise(2) syscall.
MADV_COLD can be used by a process to mark a memory range as not expected
to be used in the near future. The hint can help kernel in deciding which
pages to evict early during memory pressure.
It works for every LRU pages like MADV_[DONTNEED|FREE]. IOW, It moves
active file page -> inactive file LRU
active anon page -> inacdtive anon LRU
Unlike MADV_FREE, it doesn't move active anonymous pages to inactive file
LRU's head because MADV_COLD is a little bit different symantic.
MADV_FREE means it's okay to discard when the memory pressure because the
content of the page is *garbage* so freeing such pages is almost zero
overhead since we don't need to swap out and access afterward causes just
minor fault. Thus, it would make sense to put those freeable pages in
inactive file LRU to compete other used-once pages. It makes sense for
implmentaion point of view, too because it's not swapbacked memory any
longer until it would be re-dirtied. Even, it could give a bonus to make
them be reclaimed on swapless system. However, MADV_COLD doesn't mean
garbage so reclaiming them requires swap-out/in in the end so it's bigger
cost. Since we have designed VM LRU aging based on cost-model, anonymous
cold pages would be better to position inactive anon's LRU list, not file
LRU. Furthermore, it would help to avoid unnecessary scanning if system
doesn't have a swap device. Let's start simpler way without adding
complexity at this moment. However, keep in mind, too that it's a caveat
that workloads with a lot of pages cache are likely to ignore MADV_COLD on
anonymous memory because we rarely age anonymous LRU lists.
* man-page material
MADV_COLD (since Linux x.x)
Pages in the specified regions will be treated as less-recently-accessed
compared to pages in the system with similar access frequencies. In
contrast to MADV_FREE, the contents of the region are preserved regardless
of subsequent writes to pages.
MADV_COLD cannot be applied to locked pages, Huge TLB pages, or VM_PFNMAP
pages.
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-2-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Daniel Colascione <dancol@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tim Murray <timmurray@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both pgtable_cache_init() and pgd_cache_init() are used to initialize kmem
cache for page table allocations on several architectures that do not use
PAGE_SIZE tables for one or more levels of the page table hierarchy.
Most architectures do not implement these functions and use __weak default
NOP implementation of pgd_cache_init(). Since there is no such default
for pgtable_cache_init(), its empty stub is duplicated among most
architectures.
Rename the definitions of pgd_cache_init() to pgtable_cache_init() and
drop empty stubs of pgtable_cache_init().
Link: http://lkml.kernel.org/r/1566457046-22637-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Will Deacon <will@kernel.org> [arm64]
Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: remove quicklist page table caches".
A while ago Nicholas proposed to remove quicklist page table caches [1].
I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.
[1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com
This patch (of 3):
Remove page table allocator "quicklists". These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.
The numbers in the initial commit look interesting but probably don't
apply anymore. If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.
Also it might be better to instead make more general improvements to page
allocator if this is still so slow.
Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- add modpost warn exported symbols marked as 'static' because 'static'
and EXPORT_SYMBOL is an odd combination
- break the build early if gold linker is used
- optimize the Bison rule to produce .c and .h files by a single
pattern rule
- handle PREEMPT_RT in the module vermagic and UTS_VERSION
- warn CONFIG options leaked to the user-space except existing ones
- make single targets work properly
- rebuild modules when module linker scripts are updated
- split the module final link stage into scripts/Makefile.modfinal
- fix the missed error code in merge_config.sh
- improve the error message displayed on the attempt of the O= build
in unclean source tree
- remove 'clean-dirs' syntax
- disable -Wimplicit-fallthrough warning for Clang
- add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC
- remove ARCH_{CPP,A,C}FLAGS variables
- add $(BASH) to run bash scripts
- change *CFLAGS_<basetarget>.o to take the relative path to $(obj)
instead of the basename
- stop suppressing Clang's -Wunused-function warnings when W=1
- fix linux/export.h to avoid genksyms calculating CRC of trimmed
exported symbols
- misc cleanups
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Merge tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- add modpost warn exported symbols marked as 'static' because 'static'
and EXPORT_SYMBOL is an odd combination
- break the build early if gold linker is used
- optimize the Bison rule to produce .c and .h files by a single
pattern rule
- handle PREEMPT_RT in the module vermagic and UTS_VERSION
- warn CONFIG options leaked to the user-space except existing ones
- make single targets work properly
- rebuild modules when module linker scripts are updated
- split the module final link stage into scripts/Makefile.modfinal
- fix the missed error code in merge_config.sh
- improve the error message displayed on the attempt of the O= build in
unclean source tree
- remove 'clean-dirs' syntax
- disable -Wimplicit-fallthrough warning for Clang
- add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC
- remove ARCH_{CPP,A,C}FLAGS variables
- add $(BASH) to run bash scripts
- change *CFLAGS_<basetarget>.o to take the relative path to $(obj)
instead of the basename
- stop suppressing Clang's -Wunused-function warnings when W=1
- fix linux/export.h to avoid genksyms calculating CRC of trimmed
exported symbols
- misc cleanups
* tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits)
genksyms: convert to SPDX License Identifier for lex.l and parse.y
modpost: use __section in the output to *.mod.c
modpost: use MODULE_INFO() for __module_depends
export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols
export.h: remove defined(__KERNEL__), which is no longer needed
kbuild: allow Clang to find unused static inline functions for W=1 build
kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN
kbuild: refactor scripts/Makefile.extrawarn
merge_config.sh: ignore unwanted grep errors
kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)
modpost: add NOFAIL to strndup
modpost: add guid_t type definition
kbuild: add $(BASH) to run scripts with bash-extension
kbuild: remove ARCH_{CPP,A,C}FLAGS
kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC
kbuild: Do not enable -Wimplicit-fallthrough for clang for now
kbuild: clean up subdir-ymn calculation in Makefile.clean
kbuild: remove unneeded '+' marker from cmd_clean
kbuild: remove clean-dirs syntax
kbuild: check clean srctree even earlier
...
- add dma-mapping and block layer helpers to take care of IOMMU
merging for mmc plus subsequent fixups (Yoshihiro Shimoda)
- rework handling of the pgprot bits for remapping (me)
- take care of the dma direct infrastructure for swiotlb-xen (me)
- improve the dma noncoherent remapping infrastructure (me)
- better defaults for ->mmap, ->get_sgtable and ->get_required_mask (me)
- cleanup mmaping of coherent DMA allocations (me)
- various misc cleanups (Andy Shevchenko, me)
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Merge tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- add dma-mapping and block layer helpers to take care of IOMMU merging
for mmc plus subsequent fixups (Yoshihiro Shimoda)
- rework handling of the pgprot bits for remapping (me)
- take care of the dma direct infrastructure for swiotlb-xen (me)
- improve the dma noncoherent remapping infrastructure (me)
- better defaults for ->mmap, ->get_sgtable and ->get_required_mask
(me)
- cleanup mmaping of coherent DMA allocations (me)
- various misc cleanups (Andy Shevchenko, me)
* tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping: (41 commits)
mmc: renesas_sdhi_internal_dmac: Add MMC_CAP2_MERGE_CAPABLE
mmc: queue: Fix bigger segments usage
arm64: use asm-generic/dma-mapping.h
swiotlb-xen: merge xen_unmap_single into xen_swiotlb_unmap_page
swiotlb-xen: simplify cache maintainance
swiotlb-xen: use the same foreign page check everywhere
swiotlb-xen: remove xen_swiotlb_dma_mmap and xen_swiotlb_dma_get_sgtable
xen: remove the exports for xen_{create,destroy}_contiguous_region
xen/arm: remove xen_dma_ops
xen/arm: simplify dma_cache_maint
xen/arm: use dev_is_dma_coherent
xen/arm: consolidate page-coherent.h
xen/arm: use dma-noncoherent.h calls for xen-swiotlb cache maintainance
arm: remove wrappers for the generic dma remap helpers
dma-mapping: introduce a dma_common_find_pages helper
dma-mapping: always use VM_DMA_COHERENT for generic DMA remap
vmalloc: lift the arm flag for coherent mappings to common code
dma-mapping: provide a better default ->get_required_mask
dma-mapping: remove the dma_declare_coherent_memory export
remoteproc: don't allow modular build
...
Pull parisc updates from Helge Deller:
- Make the powerpc implementation to read elf files available as a
public kexec interface so it can be re-used on other architectures
(Sven)
- Implement kexec on parisc (Sven)
- Add kprobes on ftrace on parisc (Sven)
- Fix kernel crash with HSC-PCI cards based on card-mode Dino
- Add assembly implementations for memset, strlen, strcpy, strncpy and
strcat
- Some cleanups, documentation updates, warning fixes, ...
* 'parisc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: (25 commits)
parisc: Have git ignore generated real2.S and firmware.c
parisc: Disable HP HSC-PCI Cards to prevent kernel crash
parisc: add support for kexec_file_load() syscall
parisc: wire up kexec_file_load syscall
parisc: add kexec syscall support
parisc: add __pdc_cpu_rendezvous()
kprobes/parisc: remove arch_kprobe_on_func_entry()
kexec_elf: support 32 bit ELF files
kexec_elf: remove unused variable in kexec_elf_load()
kexec_elf: remove Elf_Rel macro
kexec_elf: remove PURGATORY_STACK_SIZE
kexec_elf: remove parsing of section headers
kexec_elf: change order of elf_*_to_cpu() functions
kexec: add KEXEC_ELF
parisc: Save some bytes in dino driver
parisc: Drop comments which are already in pci.h
parisc: Convert eisa_enumerator to use pr_cont()
parisc: Avoid warning when loading hppb driver
parisc: speed up flush_tlb_all_local with qemu
parisc: Add ALTERNATIVE_CODE() and ALT_COND_RUN_ON_QEMU
...
These files are not covered in globs from any other .gitignore files.
Signed-off-by: Jeroen Roovers <jer@gentoo.org>
Signed-off-by: Helge Deller <deller@gmx.de>
When stopping SMP cpus send them into rendezvous, so we can
start them again later (when kexec'ing a new kernel).
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
The common kprobes provides a weak implementation of
arch_kprobe_on_func_entry(). The parisc version is the same as the
common version, so remove it.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Acked-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Jens Axboe