One of the kernel-doc markups there have two "note" sections:

	./include/linux/kcsan-checks.h:346: warning: duplicate section name 'Note'

While this is not the case here, duplicated sections can cause
build issues on Sphinx. So, let's change the notes section
to use, instead, a list for those 2 notes at the same function.
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: NMarco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20f7995fab2ba85ce723203e9a7c822a55cca2af.1592895969.git.mchehab+huawei@kernel.orgSigned-off-by: NJonathan Corbet <corbet@lwn.net>

Changeset 3b0311e7ca71 ("vfs: track per-sb writeback errors and report them to syncfs")
added a variant of filemap_sample_wb_err(), but it forgot to
rename the arguments at the kernel-doc markup. Fix it.

Fix those warnings:
	./include/linux/fs.h:2845: warning: Function parameter or member 'file' not described in 'file_sample_sb_err'
	./include/linux/fs.h:2845: warning: Excess function parameter 'mapping' description in 'file_sample_sb_err'

Fixes: 3b0311e7ca71 ("vfs: track per-sb writeback errors and report them to syncfs")
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/7b33bbceb29ac80874622a2bc84127bb10103245.1592895969.git.mchehab+huawei@kernel.orgSigned-off-by: NJonathan Corbet <corbet@lwn.net>

Some fields were moved from struct phylink into phylink_config.
Update the kernel-doc markups for the config struct accordingly

Fixes: 5c05c1db ("net: phylink, dsa: eliminate phylink_fixed_state_cb()")
Reviewed-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/34970f447ff86415a6cef10a785fbef81c2819a7.1592895969.git.mchehab+huawei@kernel.orgSigned-off-by: NJonathan Corbet <corbet@lwn.net>

Changeset 6f8b12d6 ("net: napi: add hard irqs deferral feature")
added a new element at struct net_device.

Add a description for it, based on what's described at the changeset
which added such feature.

Fixes: 6f8b12d6 ("net: napi: add hard irqs deferral feature")
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/807a3840e7bc1562adefadb0535c9f47e6ab52e0.1592895969.git.mchehab+huawei@kernel.orgSigned-off-by: NJonathan Corbet <corbet@lwn.net>

There are several files that I was unable to find a proper place
for them, and 3 ones that are still in plain old text format.

Let's place those stuff behind the carpet, as we'd like to keep the
root directory clean.

We can later discuss and move those into better places.
Signed-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/11bd0d75e65a874f7c276a0aeab0fe13f3376f5f.1592203650.git.mchehab+huawei@kernel.orgSigned-off-by: NJonathan Corbet <corbet@lwn.net>

The SafeSetID LSM uses the security_task_fix_setuid hook to filter
set*uid() syscalls according to its configured security policy. In
preparation for adding analagous support in the LSM for set*gid()
syscalls, we add the requisite hook here. Tested by putting print
statements in the security_task_fix_setgid hook and seeing them get hit
during kernel boot.
Signed-off-by: NThomas Cedeno <thomascedeno@google.com>
Signed-off-by: NMicah Morton <mortonm@chromium.org>

Use __always_inline in compilation units that have instrumentation
disabled (KASAN_SANITIZE_foo.o := n) for KASAN, like it is done for
KCSAN.

Also, add common documentation for KASAN and KCSAN explaining the
attribute.

 [ bp: Massage commit message. ]
Signed-off-by: NMarco Elver <elver@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200521142047.169334-12-elver@google.com

Cleanup and move the KASAN and KCSAN related function attributes to
compiler_types.h, where the rest of the same kind live.

No functional change intended.
Signed-off-by: NMarco Elver <elver@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200521142047.169334-11-elver@google.com

It appears that compilers have trouble with nested statement
expressions. Therefore, remove one level of statement expression nesting
from the data_race() macro. This will help avoiding potential problems
in the future as its usage increases.
Reported-by: NBorislav Petkov <bp@suse.de>
Reported-by: NNathan Chancellor <natechancellor@gmail.com>
Signed-off-by: NMarco Elver <elver@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will@kernel.org>
Tested-by: NNick Desaulniers <ndesaulniers@google.com>
Link: https://lkml.kernel.org/r/20200520221712.GA21166@zn.tnic
Link: https://lkml.kernel.org/r/20200521142047.169334-10-elver@google.com

The volatile accesses no longer need to be wrapped in data_race()
because compilers that emit instrumentation distinguishing volatile
accesses are required for KCSAN.

Consequently, the explicit kcsan_check_atomic*() are no longer required
either since the compiler emits instrumentation distinguishing the
volatile accesses.

Finally, simplify __READ_ONCE_SCALAR() and remove __WRITE_ONCE_SCALAR().

 [ bp: Convert commit message to passive voice. ]
Signed-off-by: NMarco Elver <elver@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200521142047.169334-9-elver@google.com

Some compilers incorrectly inline small __no_kcsan functions, which then
results in instrumenting the accesses. For this reason, the 'noinline'
attribute was added to __no_kcsan_or_inline. All known versions of GCC
are affected by this. Supported versions of Clang are unaffected, and
never inline a no_sanitize function.

However, the attribute 'noinline' in __no_kcsan_or_inline causes
unexpected code generation in functions that are __no_kcsan and call a
__no_kcsan_or_inline function.

In certain situations it is expected that the __no_kcsan_or_inline
function is actually inlined by the __no_kcsan function, and *no* calls
are emitted. By removing the 'noinline' attribute, give the compiler
the ability to inline and generate the expected code in __no_kcsan
functions.
Signed-off-by: NMarco Elver <elver@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NWill Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/CANpmjNNOpJk0tprXKB_deiNAv_UmmORf1-2uajLhnLWQQ1hvoA@mail.gmail.com
Link: https://lkml.kernel.org/r/20200521142047.169334-6-elver@google.com

Use the following command to test nfsv4(size of file1M is 1MB):
mount -t nfs -o vers=4.0,actimeo=60 127.0.0.1/dir1 /mnt
cp file1M /mnt
du -h /mnt/file1M  -->0 within 60s, then 1M

When write is done(cp file1M /mnt), will call this:
nfs_writeback_done
  nfs4_write_done
    nfs4_write_done_cb
      nfs_writeback_update_inode
        nfs_post_op_update_inode_force_wcc_locked(change, ctime, mtime
nfs_post_op_update_inode_force_wcc_locked
   nfs_set_cache_invalid
   nfs_refresh_inode_locked
     nfs_update_inode

nfsd write response contains change, ctime, mtime, the flag will be
clear after nfs_update_inode. Howerver, write response does not contain
space_used, previous open response contains space_used whose value is 0,
so inode->i_blocks is still 0.

nfs_getattr  -->called by "du -h"
  do_update |= force_sync || nfs_attribute_cache_expired -->false in 60s
  cache_validity = READ_ONCE(NFS_I(inode)->cache_validity)
  do_update |= cache_validity & (NFS_INO_INVALID_ATTR    -->false
  if (do_update) {
        __nfs_revalidate_inode
  }

Within 60s, does not send getattr request to nfsd, thus "du -h /mnt/file1M"
is 0.

Add a NFS_INO_INVALID_BLOCKS flag, set it when nfsv4 write is done.

Fixes: 16e14375 ("NFS: More fine grained attribute tracking")
Signed-off-by: NZheng Bin <zhengbin13@huawei.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Avoid unnecessary cache sloshing by placing the buffer size
estimation update logic behind an atomic bit flag.

The size of GSS information included in each wrapped Reply does
not change during the lifetime of a GSS context. Therefore, the
au_rslack and au_ralign fields need to be updated only once after
establishing a fresh GSS credential.

Thus a slack size update must occur after a cred is created,
duplicated, renewed, or expires. I'm not sure I have this exactly
right. A trace point is introduced to track updates to these
variables to enable troubleshooting the problem if I missed a spot.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

'Page not present' event may or may not get injected depending on
guest's state. If the event wasn't injected, there is no need to
inject the corresponding 'page ready' event as the guest may get
confused. E.g. Linux thinks that the corresponding 'page not present'
event wasn't delivered *yet* and allocates a 'dummy entry' for it.
This entry is never freed.

Note, 'wakeup all' events have no corresponding 'page not present'
event and always get injected.

s390 seems to always be able to inject 'page not present', the
change is effectively a nop.
Suggested-by: NVivek Goyal <vgoyal@redhat.com>
Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200610175532.779793-2-vkuznets@redhat.com>
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=208081Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

An interesting thing happened when a guest Linux instance took a machine
check. The VMM unmapped the bad page from guest physical space and
passed the machine check to the guest.

Linux took all the normal actions to offline the page from the process
that was using it. But then guest Linux crashed because it said there
was a second machine check inside the kernel with this stack trace:

do_memory_failure
    set_mce_nospec
         set_memory_uc
              _set_memory_uc
                   change_page_attr_set_clr
                        cpa_flush
                             clflush_cache_range_opt

This was odd, because a CLFLUSH instruction shouldn't raise a machine
check (it isn't consuming the data). Further investigation showed that
the VMM had passed in another machine check because is appeared that the
guest was accessing the bad page.

Fix is to check the scope of the poison by checking the MCi_MISC register.
If the entire page is affected, then unmap the page. If only part of the
page is affected, then mark the page as uncacheable.

This assumes that VMMs will do the logical thing and pass in the "whole
page scope" via the MCi_MISC register (since they unmapped the entire
page).

  [ bp: Adjust to x86/entry changes. ]

Fixes: 284ce401 ("x86/memory_failure: Introduce {set, clear}_mce_nospec()")
Reported-by: NJue Wang <juew@google.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NJue Wang <juew@google.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200520163546.GA7977@agluck-desk2.amr.corp.intel.com

The entry rework moved interrupt entry code from the irqentry to the
noinstr section which made the irqentry section empty.

This breaks boundary checks which rely on the __irqentry_text_start/end
markers to find out whether a function in a stack trace is
interrupt/exception entry code. This affects the function graph tracer and
filter_irq_stacks().

As the IDT entry points are all sequentialy emitted this is rather simple
to unbreak by injecting __irqentry_text_start/end as global labels.

To make this work correctly:

  - Remove the IRQENTRY_TEXT section from the x86 linker script
  - Define __irqentry so it breaks the build if it's used
  - Adjust the entry mirroring in PTI
  - Remove the redundant kprobes and unwinder bound checks
Reported-by: NQian Cai <cai@lca.pw>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

vmlinux.o: warning: objtool: debug_locks_off()+0xd: call to __debug_locks_off() leaves .noinstr.text section
vmlinux.o: warning: objtool: match_held_lock()+0x6a: call to look_up_lock_class.isra.0() leaves .noinstr.text section
vmlinux.o: warning: objtool: lock_is_held_type()+0x90: call to lockdep_recursion_finish() leaves .noinstr.text section
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200603114052.185201076@infradead.org

The typical pattern for trace_hardirqs_off_prepare() is:

  ENTRY
    lockdep_hardirqs_off(); // because hardware
    ... do entry magic
    instrumentation_begin();
    trace_hardirqs_off_prepare();
    ... do actual work
    trace_hardirqs_on_prepare();
    lockdep_hardirqs_on_prepare();
    instrumentation_end();
    ... do exit magic
    lockdep_hardirqs_on();

which shows that it's named wrong, rename it to
trace_hardirqs_off_finish(), as it concludes the hardirq_off transition.

Also, given that the above is the only correct order, make the traditional
all-in-one trace_hardirqs_off() follow suit.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200529213321.415774872@infradead.org

Like __irq_enter/exit() but without time accounting. To be used for "empty"
system vectors like the scheduler IPI to avoid the overhead.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Reviewed-by: NAndy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202117.671682341@linutronix.de

irq_enter()/exit() currently include RCU handling. To properly separate the RCU
handling code, provide variants which contain only the non-RCU related
functionality.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Reviewed-by: NAndy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20200521202117.567023613@linutronix.de

The hardware latency tracer calls into instrumentable functions. Move the
calls into the RCU watching sections and annotate them.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NAndy Lutomirski <luto@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20200521202116.904176298@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

For code that needs the ultimate performance (it can inline the @cmp
function too) or simply needs to avoid calling external functions for
whatever reason, provide an __always_inline variant of bsearch().

[ tglx: Renamed to __inline_bsearch() as suggested by Andy ]
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NAlexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: NAndy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135313.624443814@linutronix.de

context tracking lacks a few protection mechanisms against instrumentation:

 - While the core functions are marked NOKPROBE they lack protection
   against function tracing which is required as the function entry/exit
   points can be utilized by BPF.

 - static functions invoked from the protected functions need to be marked
   as well as they can be instrumented otherwise.

 - using plain inline allows the compiler to emit traceable and probable
   functions.

Fix this by marking the functions noinstr and converting the plain inlines
to __always_inline.

The NOKPROBE_SYMBOL() annotations are removed as the .noinstr.text section
is already excluded from being probed.

Cures the following objtool warnings:

 vmlinux.o: warning: objtool: enter_from_user_mode()+0x34: call to __context_tracking_exit() leaves .noinstr.text section
 vmlinux.o: warning: objtool: prepare_exit_to_usermode()+0x29: call to __context_tracking_enter() leaves .noinstr.text section
 vmlinux.o: warning: objtool: syscall_return_slowpath()+0x29: call to __context_tracking_enter() leaves .noinstr.text section
 vmlinux.o: warning: objtool: do_syscall_64()+0x7f: call to __context_tracking_enter() leaves .noinstr.text section
 vmlinux.o: warning: objtool: do_int80_syscall_32()+0x3d: call to __context_tracking_enter() leaves .noinstr.text section
 vmlinux.o: warning: objtool: do_fast_syscall_32()+0x9c: call to __context_tracking_enter() leaves .noinstr.text section

and generates new ones...
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NMasami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: NAlexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134340.811520478@linutronix.de

Currently instrumentation of atomic primitives is done at the architecture
level, while composites or fallbacks are provided at the generic level.

The result is that there are no uninstrumented variants of the
fallbacks. Since there is now need of such variants to isolate text poke
from any form of instrumentation invert this ordering.

Doing this means moving the instrumentation into the generic code as
well as having (for now) two variants of the fallbacks.

Notes:

 - the various *cond_read* primitives are not proper fallbacks
   and got moved into linux/atomic.c. No arch_ variants are
   generated because the base primitives smp_cond_load*()
   are instrumented.

 - once all architectures are moved over to arch_atomic_ one of the
   fallback variants can be removed and some 2300 lines reclaimed.

 - atomic_{read,set}*() are no longer double-instrumented
Reported-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20200505134058.769149955@linutronix.de

Use __always_inline for atomic fallback wrappers. When building for size
(CC_OPTIMIZE_FOR_SIZE), some compilers appear to be less inclined to
inline even relatively small static inline functions that are assumed to
be inlinable such as atomic ops. This can cause problems, for example in
UACCESS regions.

While the fallback wrappers aren't pure wrappers, they are trivial
nonetheless, and the function they wrap should determine the final
inlining policy.

For x86 tinyconfig we observe:
- vmlinux baseline: 1315988
- vmlinux with patch: 1315928 (-60 bytes)

[ tglx: Cherry-picked from KCSAN ]
Suggested-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NMarco Elver <elver@google.com>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Signed-off-by: NPaul E. McKenney <paulmck@kernel.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Switch the function documentation to kerneldoc comments, and add
WARN_ON_ONCE asserts that the calling thread is a kernel thread and does
not have ->mm set (or has ->mm set in the case of unuse_mm).

Also give the functions a kthread_ prefix to better document the use case.

[hch@lst.de: fix a comment typo, cover the newly merged use_mm/unuse_mm caller in vfio]
  Link: http://lkml.kernel.org/r/20200416053158.586887-3-hch@lst.de
[sfr@canb.auug.org.au: powerpc/vas: fix up for {un}use_mm() rename]
  Link: http://lkml.kernel.org/r/20200422163935.5aa93ba5@canb.auug.org.auSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Tested-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Acked-by: NFelix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [usb]
Acked-by: NHaren Myneni <haren@linux.ibm.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Link: http://lkml.kernel.org/r/20200404094101.672954-6-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "improve use_mm / unuse_mm", v2.

This series improves the use_mm / unuse_mm interface by better documenting
the assumptions, and my taking the set_fs manipulations spread over the
callers into the core API.

This patch (of 3):

Use the proper API instead.

Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de

These helpers are only for use with kernel threads, and I will tie them
more into the kthread infrastructure going forward.  Also move the
prototypes to kthread.h - mmu_context.h was a little weird to start with
as it otherwise contains very low-level MM bits.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Tested-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Acked-by: NFelix Kuehling <Felix.Kuehling@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20200404094101.672954-1-hch@lst.de
Link: http://lkml.kernel.org/r/20200416053158.586887-1-hch@lst.de
Link: http://lkml.kernel.org/r/20200404094101.672954-5-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Modify the variable type of 'skip' member of struct stack_trace.
In theory, the 'skip' variable type should be unsigned int.
There are two reasons:
- The 'skip' only has two situation, 1)Positive value, 2)Zero
- The 'skip' of struct stack_trace has inconsistent type with struct
  stack_trace_data, it makes a bit confusion in the relationship between
  struct stack_trace and stack_trace_data.
Signed-off-by: NWalter Wu <walter-zh.wu@mediatek.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: http://lkml.kernel.org/r/20200421013511.5960-1-walter-zh.wu@mediatek.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

While making other modifications it was easy to confuse the two struct
members node_zones and node_zonelists.  For those already familiar with
the code, this might seem to be a silly patch, but it's quite helpful to
disambiguate the similar-sounding fields

While here, add a small comment on why nr_zones isn't simply MAX_NR_ZONES
Signed-off-by: NBen Widawsky <ben.widawsky@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200520205443.2757414-1-ben.widawsky@intel.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The RISC-V per-HART local interrupt controller manages software
interrupts, timer interrupts, external interrupts (which are routed
via the platform level interrupt controller) and other per-HART
local interrupts.

We add a driver for the RISC-V local interrupt controller, which
eventually replaces the RISC-V architecture code, allowing for a
better split between arch code and drivers.

The driver is compliant with RISC-V Hart-Level Interrupt Controller
DT bindings located at:
Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt
Co-developed-by: NPalmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: NAnup Patel <anup.patel@wdc.com>
[Palmer: Cleaned up warnings]
Signed-off-by: NPalmer Dabbelt <palmer@dabbelt.com>

The dynamic key update for addr_list_lock still causes troubles,
for example the following race condition still exists:

CPU 0:				CPU 1:
(RCU read lock)			(RTNL lock)
dev_mc_seq_show()		netdev_update_lockdep_key()
				  -> lockdep_unregister_key()
 -> netif_addr_lock_bh()

because lockdep doesn't provide an API to update it atomically.
Therefore, we have to move it back to static keys and use subclass
for nest locking like before.

In commit 1a33e10e ("net: partially revert dynamic lockdep key
changes"), I already reverted most parts of commit ab92d68f
("net: core: add generic lockdep keys").

This patch reverts the rest and also part of commit f3b0a18b
("net: remove unnecessary variables and callback"). After this
patch, addr_list_lock changes back to using static keys and
subclasses to satisfy lockdep. Thanks to dev->lower_level, we do
not have to change back to ->ndo_get_lock_subclass().

And hopefully this reduces some syzbot lockdep noises too.

Reported-by: syzbot+f3a0e80c34b3fc28ac5e@syzkaller.appspotmail.com
Cc: Taehee Yoo <ap420073@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit b75b7ca7.

The patch restores a helper that was not necessary after direct IO port
to iomap infrastructure, which gets reverted.
Signed-off-by: NDavid Sterba <dsterba@suse.com>

__read_mostly can easily be misused by folks, its not meant for just
read-only data.  There are performance reasons for using it, but we also
don't provide any guidance about its use.  Provide a bit more guidance
over its use.
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NKees Cook <keescook@chromium.org>
Acked-by: NChristoph Lameter <cl@linux.com>
Acked-by: NRafael Aquini <aquini@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox <willy@infradead.org>
Link: http://lkml.kernel.org/r/20200507161424.2584-1-mcgrof@kernel.orgSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Except for historical confusion in the kprobes/uprobes and bpf tracers,
which has been fixed now, there is no good reason to ever allow user
memory accesses from probe_kernel_read.  Switch probe_kernel_read to only
read from kernel memory.

[akpm@linux-foundation.org: update it for "mm, dump_page(): do not crash with invalid mapping pointer"]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-17-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All users are gone now.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-16-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently architectures have to override every routine that probes
kernel memory, which includes a pure read and strcpy, both in strict
and not strict variants.  Just provide a single arch hooks instead to
make sure all architectures cover all the cases.

[akpm@linux-foundation.org: fix !CONFIG_X86_64 build]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-11-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This matches the naming of strnlen_user, and also makes it more clear
what the function is supposed to do.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-9-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This matches the naming of strncpy_from_user_nofault, and also makes it
more clear what the function is supposed to do.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-8-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This matches the naming of strncpy_from_user, and also makes it more
clear what the function is supposed to do.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-7-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Many of the maccess routines have a copy of the kerneldoc comment
in the header.  Remove it as it is not useful and will get out of
sync sooner or later.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200521152301.2587579-4-hch@lst.deSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>