Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-12-03
The main changes are:
1) Support BTF in kernel modules, from Andrii.
2) Introduce preferred busy-polling, from Björn.
3) bpf_ima_inode_hash() and bpf_bprm_opts_set() helpers, from KP Singh.
4) Memcg-based memory accounting for bpf objects, from Roman.
5) Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks, from Stanislav.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (118 commits)
selftests/bpf: Fix invalid use of strncat in test_sockmap
libbpf: Use memcpy instead of strncpy to please GCC
selftests/bpf: Add fentry/fexit/fmod_ret selftest for kernel module
selftests/bpf: Add tp_btf CO-RE reloc test for modules
libbpf: Support attachment of BPF tracing programs to kernel modules
libbpf: Factor out low-level BPF program loading helper
bpf: Allow to specify kernel module BTFs when attaching BPF programs
bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier
selftests/bpf: Add CO-RE relocs selftest relying on kernel module BTF
selftests/bpf: Add support for marking sub-tests as skipped
selftests/bpf: Add bpf_testmod kernel module for testing
libbpf: Add kernel module BTF support for CO-RE relocations
libbpf: Refactor CO-RE relocs to not assume a single BTF object
libbpf: Add internal helper to load BTF data by FD
bpf: Keep module's btf_data_size intact after load
bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address()
selftests/bpf: Add Userspace tests for TCP_WINDOW_CLAMP
bpf: Adds support for setting window clamp
samples/bpf: Fix spelling mistake "recieving" -> "receiving"
bpf: Fix cold build of test_progs-no_alu32
...
====================
Link: https://lore.kernel.org/r/20201204021936.85653-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This option lets a user set a per socket NAPI budget for
busy-polling. If the options is not set, it will use the default of 8.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/bpf/20201130185205.196029-3-bjorn.topel@gmail.com
The existing busy-polling mode, enabled by the SO_BUSY_POLL socket
option or system-wide using the /proc/sys/net/core/busy_read knob, is
an opportunistic. That means that if the NAPI context is not
scheduled, it will poll it. If, after busy-polling, the budget is
exceeded the busy-polling logic will schedule the NAPI onto the
regular softirq handling.
One implication of the behavior above is that a busy/heavy loaded NAPI
context will never enter/allow for busy-polling. Some applications
prefer that most NAPI processing would be done by busy-polling.
This series adds a new socket option, SO_PREFER_BUSY_POLL, that works
in concert with the napi_defer_hard_irqs and gro_flush_timeout
knobs. The napi_defer_hard_irqs and gro_flush_timeout knobs were
introduced in commit 6f8b12d661 ("net: napi: add hard irqs deferral
feature"), and allows for a user to defer interrupts to be enabled and
instead schedule the NAPI context from a watchdog timer. When a user
enables the SO_PREFER_BUSY_POLL, again with the other knobs enabled,
and the NAPI context is being processed by a softirq, the softirq NAPI
processing will exit early to allow the busy-polling to be performed.
If the application stops performing busy-polling via a system call,
the watchdog timer defined by gro_flush_timeout will timeout, and
regular softirq handling will resume.
In summary; Heavy traffic applications that prefer busy-polling over
softirq processing should use this option.
Example usage:
$ echo 2 | sudo tee /sys/class/net/ens785f1/napi_defer_hard_irqs
$ echo 200000 | sudo tee /sys/class/net/ens785f1/gro_flush_timeout
Note that the timeout should be larger than the userspace processing
window, otherwise the watchdog will timeout and fall back to regular
softirq processing.
Enable the SO_BUSY_POLL/SO_PREFER_BUSY_POLL options on your socket.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/bpf/20201130185205.196029-2-bjorn.topel@gmail.com
We call arch_cpu_idle() with RCU disabled, but then use
local_irq_{en,dis}able(), which invokes tracing, which relies on RCU.
Switch all arch_cpu_idle() implementations to use
raw_local_irq_{en,dis}able() and carefully manage the
lockdep,rcu,tracing state like we do in entry.
(XXX: we really should change arch_cpu_idle() to not return with
interrupts enabled)
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20201120114925.594122626@infradead.org
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 <joe@perches.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull more parisc updates from Helge Deller:
- During this merge window O_NONBLOCK was changed to become 000200000,
but we missed that the syscalls timerfd_create(), signalfd4(),
eventfd2(), pipe2(), inotify_init1() and userfaultfd() do a strict
bit-wise check of the flags parameter.
To provide backward compatibility with existing userspace we
introduce parisc specific wrappers for those syscalls which filter
out the old O_NONBLOCK value and replaces it with the new one.
- Prevent HIL bus driver to get stuck when keyboard or mouse isn't
attached
- Improve error return codes when setting rtc time
- Minor documentation fix in pata_ns87415.c
* 'parisc-5.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
ata: pata_ns87415.c: Document support on parisc with superio chip
parisc: Add wrapper syscalls to fix O_NONBLOCK flag usage
hil/parisc: Disable HIL driver when it gets stuck
parisc: Improve error return codes when setting rtc time
The commit 75ae04206a ("parisc: Define O_NONBLOCK to become
000200000") changed the O_NONBLOCK constant to have only one bit set
(like all other architectures). This change broke some existing
userspace code (e.g. udevadm, systemd-udevd, elogind) which called
specific syscalls which do strict value checking on their flag
parameter.
This patch adds wrapper functions for the relevant syscalls. The
wrappers masks out any old invalid O_NONBLOCK flags, reports in the
syslog if the old O_NONBLOCK value was used and then calls the target
syscall with the new O_NONBLOCK value.
Fixes: 75ae04206a ("parisc: Define O_NONBLOCK to become 000200000")
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: Meelis Roos <mroos@linux.ee>
Tested-by: Jeroen Roovers <jer@xs4all.nl>
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Merge tag 'arch-cleanup-2020-10-22' of git://git.kernel.dk/linux-block
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()
The HP 730 machine returned strange errors when I tried setting the rtc
time. Add some debug code to improve the possibility to trace errors
and document that hppa probably has as Y2k38 problem.
Signed-off-by: Helge Deller <deller@gmx.de>
Pull initial set_fs() removal from Al Viro:
"Christoph's set_fs base series + fixups"
* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: Allow a NULL pos pointer to __kernel_read
fs: Allow a NULL pos pointer to __kernel_write
powerpc: remove address space overrides using set_fs()
powerpc: use non-set_fs based maccess routines
x86: remove address space overrides using set_fs()
x86: make TASK_SIZE_MAX usable from assembly code
x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h
lkdtm: remove set_fs-based tests
test_bitmap: remove user bitmap tests
uaccess: add infrastructure for kernel builds with set_fs()
fs: don't allow splice read/write without explicit ops
fs: don't allow kernel reads and writes without iter ops
sysctl: Convert to iter interfaces
proc: add a read_iter method to proc proc_ops
proc: cleanup the compat vs no compat file ops
proc: remove a level of indentation in proc_get_inode
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
<sys/uio.h> 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_PAGEOUT
Permission 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.au
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Christian Brauner <christian@brauner.io>
Cc: Daniel Colascione <dancol@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Dias <joaodias@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: SeongJae Park <sj38.park@gmail.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: <linux-man@vger.kernel.org>
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 <torvalds@linux-foundation.org>
All the callers currently do this, clean it up and move the clearing
into tracehook_notify_resume() instead.
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull parisc updates from Helge Deller:
- Added fw_cfg support for parisc on qemu
- Added font support in sti text console driver for byte- and word-mode
ROMs
- Switch to more fine grained lws locks and improve spinlock handling
- Add ioread64_hi_lo() and iowrite64_hi_lo() to avoid 0-day linking
errors
- Mark pointers volatile in __xchg8(), __xchg32() and __xchg64() to
help compiler
- Header file cleanups, mostly removal of unused HP-UX compat defines
- Drop one bit from our O_NONBLOCK define to become now 000200000
- Add MAP_UNINITIALIZED define to avoid userspace compile errors
- Drop CONFIG_IDE from defconfigs
- Speed up synchronize_caches() on UP machines
- Rewrite tlb flush threshold calculation
- Comment fixes and cleanups
* 'parisc-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc/sticon: Add user font support
parisc/sticon: Always register sticon console driver
parisc: Add MAP_UNINITIALIZED define
parisc: Improve spinlock handling
parisc: Install vmlinuz instead of zImage file
parisc: Rewrite tlb flush threshold calculation
parisc: Switch to more fine grained lws locks
parisc: Mark pointers volatile in __xchg8(), __xchg32() and __xchg64()
parisc: Fix comments and enable interrupts later
parisc: Add alternative patching to synchronize_caches define
parisc: Add ioread64_hi_lo() and iowrite64_hi_lo()
parisc: disable CONFIG_IDE in defconfigs
parisc: Drop useless comments in uapi/asm/signal.h
parisc: Define O_NONBLOCK to become 000200000
parisc: Drop HP-UX specific fcntl and signal flags
parisc: Avoid external interrupts when IPI finishes
parisc: Add qemu fw_cfg interface
fw_cfg: Add support for parisc architecture
- rework the non-coherent DMA allocator
- move private definitions out of <linux/dma-mapping.h>
- lower CMA_ALIGNMENT (Paul Cercueil)
- remove the omap1 dma address translation in favor of the common
code
- make dma-direct aware of multiple dma offset ranges (Jim Quinlan)
- support per-node DMA CMA areas (Barry Song)
- increase the default seg boundary limit (Nicolin Chen)
- misc fixes (Robin Murphy, Thomas Tai, Xu Wang)
- various cleanups
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Merge tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- rework the non-coherent DMA allocator
- move private definitions out of <linux/dma-mapping.h>
- lower CMA_ALIGNMENT (Paul Cercueil)
- remove the omap1 dma address translation in favor of the common code
- make dma-direct aware of multiple dma offset ranges (Jim Quinlan)
- support per-node DMA CMA areas (Barry Song)
- increase the default seg boundary limit (Nicolin Chen)
- misc fixes (Robin Murphy, Thomas Tai, Xu Wang)
- various cleanups
* tag 'dma-mapping-5.10' of git://git.infradead.org/users/hch/dma-mapping: (63 commits)
ARM/ixp4xx: add a missing include of dma-map-ops.h
dma-direct: simplify the DMA_ATTR_NO_KERNEL_MAPPING handling
dma-direct: factor out a dma_direct_alloc_from_pool helper
dma-direct check for highmem pages in dma_direct_alloc_pages
dma-mapping: merge <linux/dma-noncoherent.h> into <linux/dma-map-ops.h>
dma-mapping: move large parts of <linux/dma-direct.h> to kernel/dma
dma-mapping: move dma-debug.h to kernel/dma/
dma-mapping: remove <asm/dma-contiguous.h>
dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>
dma-contiguous: remove dma_contiguous_set_default
dma-contiguous: remove dev_set_cma_area
dma-contiguous: remove dma_declare_contiguous
dma-mapping: split <linux/dma-mapping.h>
cma: decrease CMA_ALIGNMENT lower limit to 2
firewire-ohci: use dma_alloc_pages
dma-iommu: implement ->alloc_noncoherent
dma-mapping: add new {alloc,free}_noncoherent dma_map_ops methods
dma-mapping: add a new dma_alloc_pages API
dma-mapping: remove dma_cache_sync
53c700: convert to dma_alloc_noncoherent
...
We will not allow unitialized anon mmaps, but we need this define
to prevent build errors, e.g. the debian foot package.
Suggested-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Use READ_ONCE() to check if spinlock is locked.
The other changes are cleanups.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Increase the number of lws locks to 256 entries (instead of 16) and
choose lock entry based on bits 3-11 (instead of 4-7) of the relevant
address. With this change we archieve more fine-grained locking in
futex syscalls and thus reduce the number of possible stalls.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Let the complier treat the pointers volatile to ensure that they get
accessed atomicly.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Correct the comments: The jump is forwards, not backwards.
Enable the interrupts after %r29 (reference param area) was loaded.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
This change allows the sync barrier instruction to be patched to a nop.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
The kernel test robot reports missing functions. Add them.
hppa-linux-ld: drivers/firmware/arm_scmi/perf.o: in function `scmi_perf_fc_ring_db':
(.text+0x610): undefined reference to `ioread64_hi_lo'
(.text+0x63c): undefined reference to `iowrite64_hi_lo'
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Enable libata support for the Nat Semi NS87415 controller, and
disable the soon to be removed legacy ide driver entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
HPUX has separate NDELAY & NONBLOCK values. In the past we wanted to
be able to run HP-UX binaries natively on parisc Linux which is why
we defined O_NONBLOCK to 000200004 to distinguish NDELAY & NONBLOCK
bits.
But with 2 bits set in this bitmask we often ran into compatibility
issues with other Linux applications which often only test one bit (or
even compare the values).
To avoid such issues in the future, this patch changes O_NONBLOCK to
become 000200000. That way old programs will still be functional, and
for new programs we now have only one bit set.
Update the comment about SOCK_NONBLOCK too.
Signed-off-by: Helge Deller <deller@gmx.de>
Those flags are nowhere used in the Linux kernel and were added when we
still wanted to support HP-UX in a compat mode. Since we never will
support HP-UX, drop those flags.
Signed-off-by: Helge Deller <deller@gmx.de>
When running on qemu, SeaBIOS-hppa stores the iomem address for the
emulated fw_cfg port in PAGE0_>pad0[2/3]. Let the Linux driver
auto-configure the fw_cfg interface with it, so that the fw_cfg info
shows up in /sys/firmware/qemu_fw_cfg.
Signed-off-by: Helge Deller <deller@gmx.de>
- heavily refactor seccomp selftests (and clone3 selftests dependency) to
fix powerpc (Kees Cook, Thadeu Lima de Souza Cascardo)
- fix style issue in selftests (Zou Wei)
- upgrade "unknown action" from KILL_THREAD to KILL_PROCESS (Rich Felker)
- replace task_pt_regs(current) with current_pt_regs() (Denis Efremov)
- fix corner-case race in USER_NOTIF (Jann Horn)
- make CONFIG_SECCOMP no longer per-arch (YiFei Zhu)
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Merge tag 'seccomp-v5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp updates from Kees Cook:
"The bulk of the changes are with the seccomp selftests to accommodate
some powerpc-specific behavioral characteristics. Additional cleanups,
fixes, and improvements are also included:
- heavily refactor seccomp selftests (and clone3 selftests
dependency) to fix powerpc (Kees Cook, Thadeu Lima de Souza
Cascardo)
- fix style issue in selftests (Zou Wei)
- upgrade "unknown action" from KILL_THREAD to KILL_PROCESS (Rich
Felker)
- replace task_pt_regs(current) with current_pt_regs() (Denis
Efremov)
- fix corner-case race in USER_NOTIF (Jann Horn)
- make CONFIG_SECCOMP no longer per-arch (YiFei Zhu)"
* tag 'seccomp-v5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (23 commits)
seccomp: Make duplicate listener detection non-racy
seccomp: Move config option SECCOMP to arch/Kconfig
selftests/clone3: Avoid OS-defined clone_args
selftests/seccomp: powerpc: Set syscall return during ptrace syscall exit
selftests/seccomp: Allow syscall nr and ret value to be set separately
selftests/seccomp: Record syscall during ptrace entry
selftests/seccomp: powerpc: Fix seccomp return value testing
selftests/seccomp: Remove SYSCALL_NUM_RET_SHARE_REG in favor of SYSCALL_RET_SET
selftests/seccomp: Avoid redundant register flushes
selftests/seccomp: Convert REGSET calls into ARCH_GETREG/ARCH_SETREG
selftests/seccomp: Convert HAVE_GETREG into ARCH_GETREG/ARCH_SETREG
selftests/seccomp: Remove syscall setting #ifdefs
selftests/seccomp: mips: Remove O32-specific macro
selftests/seccomp: arm64: Define SYSCALL_NUM_SET macro
selftests/seccomp: arm: Define SYSCALL_NUM_SET macro
selftests/seccomp: mips: Define SYSCALL_NUM_SET macro
selftests/seccomp: Provide generic syscall setting macro
selftests/seccomp: Refactor arch register macros to avoid xtensa special case
selftests/seccomp: Use __NR_mknodat instead of __NR_mknod
selftests/seccomp: Use bitwise instead of arithmetic operator for flags
...
Pull compat mount cleanups from Al Viro:
"The last remnants of mount(2) compat buried by Christoph.
Buried into NFS, that is.
Generally I'm less enthusiastic about "let's use in_compat_syscall()
deep in call chain" kind of approach than Christoph seems to be, but
in this case it's warranted - that had been an NFS-specific wart,
hopefully not to be repeated in any other filesystems (read: any new
filesystem introducing non-text mount options will get NAKed even if
it doesn't mess the layout up).
IOW, not worth trying to grow an infrastructure that would avoid that
use of in_compat_syscall()..."
* 'compat.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: remove compat_sys_mount
fs,nfs: lift compat nfs4 mount data handling into the nfs code
nfs: simplify nfs4_parse_monolithic
Pull compat quotactl cleanups from Al Viro:
"More Christoph's compat cleanups: quotactl(2)"
* 'work.quota-compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
quota: simplify the quotactl compat handling
compat: add a compat_need_64bit_alignment_fixup() helper
compat: lift compat_s64 and compat_u64 to <asm-generic/compat.h>
Pull compat iovec cleanups from Al Viro:
"Christoph's series around import_iovec() and compat variant thereof"
* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
security/keys: remove compat_keyctl_instantiate_key_iov
mm: remove compat_process_vm_{readv,writev}
fs: remove compat_sys_vmsplice
fs: remove the compat readv/writev syscalls
fs: remove various compat readv/writev helpers
iov_iter: transparently handle compat iovecs in import_iovec
iov_iter: refactor rw_copy_check_uvector and import_iovec
iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c
compat.h: fix a spelling error in <linux/compat.h>
Pull copy_and_csum cleanups from Al Viro:
"Saner calling conventions for csum_and_copy_..._user() and friends"
[ Removing 800+ lines of code and cleaning stuff up is good - Linus ]
* 'work.csum_and_copy' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ppc: propagate the calling conventions change down to csum_partial_copy_generic()
amd64: switch csum_partial_copy_generic() to new calling conventions
sparc64: propagate the calling convention changes down to __csum_partial_copy_...()
xtensa: propagate the calling conventions change down into csum_partial_copy_generic()
mips: propagate the calling convention change down into __csum_partial_copy_..._user()
mips: __csum_partial_copy_kernel() has no users left
mips: csum_and_copy_{to,from}_user() are never called under KERNEL_DS
sparc32: propagate the calling conventions change down to __csum_partial_copy_sparc_generic()
i386: propagate the calling conventions change down to csum_partial_copy_generic()
sh: propage the calling conventions change down to csum_partial_copy_generic()
m68k: get rid of zeroing destination on error in csum_and_copy_from_user()
arm: propagate the calling convention changes down to csum_partial_copy_from_user()
alpha: propagate the calling convention changes down to csum_partial_copy.c helpers
saner calling conventions for csum_and_copy_..._user()
csum_and_copy_..._user(): pass 0xffffffff instead of 0 as initial sum
csum_partial_copy_nocheck(): drop the last argument
unify generic instances of csum_partial_copy_nocheck()
icmp_push_reply(): reorder adding the checksum up
skb_copy_and_csum_bits(): don't bother with the last argument
because the heuristics that various linkers & compilers use to handle them
(include these bits into the output image vs discarding them silently)
are both highly idiosyncratic and also version dependent.
Instead of this historically problematic mess, this tree by Kees Cook (et al)
adds build time asserts and build time warnings if there's any orphan section
in the kernel or if a section is not sized as expected.
And because we relied on so many silent assumptions in this area, fix a metric
ton of dependencies and some outright bugs related to this, before we can
finally enable the checks on the x86, ARM and ARM64 platforms.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'core-build-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull orphan section checking from Ingo Molnar:
"Orphan link sections were a long-standing source of obscure bugs,
because the heuristics that various linkers & compilers use to handle
them (include these bits into the output image vs discarding them
silently) are both highly idiosyncratic and also version dependent.
Instead of this historically problematic mess, this tree by Kees Cook
(et al) adds build time asserts and build time warnings if there's any
orphan section in the kernel or if a section is not sized as expected.
And because we relied on so many silent assumptions in this area, fix
a metric ton of dependencies and some outright bugs related to this,
before we can finally enable the checks on the x86, ARM and ARM64
platforms"
* tag 'core-build-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
x86/boot/compressed: Warn on orphan section placement
x86/build: Warn on orphan section placement
arm/boot: Warn on orphan section placement
arm/build: Warn on orphan section placement
arm64/build: Warn on orphan section placement
x86/boot/compressed: Add missing debugging sections to output
x86/boot/compressed: Remove, discard, or assert for unwanted sections
x86/boot/compressed: Reorganize zero-size section asserts
x86/build: Add asserts for unwanted sections
x86/build: Enforce an empty .got.plt section
x86/asm: Avoid generating unused kprobe sections
arm/boot: Handle all sections explicitly
arm/build: Assert for unwanted sections
arm/build: Add missing sections
arm/build: Explicitly keep .ARM.attributes sections
arm/build: Refactor linker script headers
arm64/build: Assert for unwanted sections
arm64/build: Add missing DWARF sections
arm64/build: Use common DISCARDS in linker script
arm64/build: Remove .eh_frame* sections due to unwind tables
...
In order to make adding configurable features into seccomp easier,
it's better to have the options at one single location, considering
especially that the bulk of seccomp code is arch-independent. An quick
look also show that many SECCOMP descriptions are outdated; they talk
about /proc rather than prctl.
As a result of moving the config option and keeping it default on,
architectures arm, arm64, csky, riscv, sh, and xtensa did not have SECCOMP
on by default prior to this and SECCOMP will be default in this change.
Architectures microblaze, mips, powerpc, s390, sh, and sparc have an
outdated depend on PROC_FS and this dependency is removed in this change.
Suggested-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/lkml/CAG48ez1YWz9cnp08UZgeieYRhHdqh-ch7aNwc4JRBnGyrmgfMg@mail.gmail.com/
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
[kees: added HAVE_ARCH_SECCOMP help text, tweaked wording]
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/9ede6ef35c847e58d61e476c6a39540520066613.1600951211.git.yifeifz2@illinois.edu
Split out all the bits that are purely for dma_map_ops implementations
and related code into a new <linux/dma-map-ops.h> header so that they
don't get pulled into all the drivers. That also means the architecture
specific <asm/dma-mapping.h> is not pulled in by <linux/dma-mapping.h>
any more, which leads to a missing includes that were pulled in by the
x86 or arm versions in a few not overly portable drivers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Now that import_iovec handles compat iovecs, the native syscalls
can be used for the compat case as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that import_iovec handles compat iovecs, the native vmsplice syscall
can be used for the compat case as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that import_iovec handles compat iovecs, the native readv and writev
syscalls can be used for the compat case as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All users are gone now, remove the API.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
compat_sys_mount is identical to the regular sys_mount now, so remove it
and use the native version everywhere.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
lift the compat_s64 and compat_u64 definitions into common code using the
COMPAT_FOR_U64_ALIGNMENT symbol for the x86 special case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a CONFIG_SET_FS option that is selected by architecturess that
implement set_fs, which is all of them initially. If the option is not
set stubs for routines related to overriding the address space are
provided so that architectures can start to opt out of providing set_fs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The .comment section doesn't belong in STABS_DEBUG. Split it out into a
new macro named ELF_DETAILS. This will gain other non-debug sections
that need to be accounted for when linking with --orphan-handling=warn.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20200821194310.3089815-5-keescook@chromium.org
All callers of these primitives will
* discard anything we might've copied in case of error
* ignore the csum value in case of error
* always pass 0xffffffff as the initial sum, so the
resulting csum value (in case of success, that is) will never be 0.
That suggest the following calling conventions:
* don't pass err_ptr - just return 0 on error.
* don't bother with zeroing destination, etc. in case of error
* don't pass the initial sum - just use 0xffffffff.
This commit does the minimal conversion in the instances of csum_and_copy_...();
the changes of actual asm code behind them are done later in the series.
Note that this asm code is often shared with csum_partial_copy_nocheck();
the difference is that csum_partial_copy_nocheck() passes 0 for initial
sum while csum_and_copy_..._user() pass 0xffffffff. Fortunately, we are
free to pass 0xffffffff in all cases and subsequent patches will use that
freedom without any special comments.
A part that could be split off: parisc and uml/i386 claimed to have
csum_and_copy_to_user() instances of their own, but those were identical
to the generic one, so we simply drop them. Not sure if it's worth
a separate commit...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
