When exporting static_call_key; with EXPORT_STATIC_CALL*(), the module
can use static_call_update() to change the function called.  This is
not desirable in general.

Not exporting static_call_key however also disallows usage of
static_call(), since objtool needs the key to construct the
static_call_site.

Solve this by allowing objtool to create the static_call_site using
the trampoline address when it builds a module and cannot find the
static_call_key symbol. The module loader will then try and map the
trampole back to a key before it constructs the normal sites list.

Doing this requires a trampoline -> key associsation, so add another
magic section that keeps those.
Originally-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210127231837.ifddpn7rhwdaepiu@treble

Provide static call to control IRQ preemption (called in CONFIG_PREEMPT)
so that we can override its behaviour when preempt= is overriden.

Since the default behaviour is full preemption, its call is
initialized to provide IRQ preemption when preempt= isn't passed.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-8-frederic@kernel.org

Provide static calls to control cond_resched() (called in !CONFIG_PREEMPT)
and might_resched() (called in CONFIG_PREEMPT_VOLUNTARY) to that we
can override their behaviour when preempt= is overriden.

Since the default behaviour is full preemption, both their calls are
ignored when preempt= isn't passed.

  [fweisbec: branch might_resched() directly to __cond_resched(), only
             define static calls when PREEMPT_DYNAMIC]
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-6-frederic@kernel.org

DECLARE_STATIC_CALL() must pass the original function targeted for a
given static call. But DEFINE_STATIC_CALL() may want to initialize it as
off. In this case we can't pass NULL (for functions without return value)
or __static_call_return0 (for functions returning a value) directly
to DEFINE_STATIC_CALL() as that may trigger a static call redeclaration
with a different function prototype. Type casts neither can work around
that as they don't get along with typeof().

The proper way to do that for functions that don't return a value is
to use DEFINE_STATIC_CALL_NULL(). But functions returning a actual value
don't have an equivalent yet.

Provide DEFINE_STATIC_CALL_RET0() to solve this situation.
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-3-frederic@kernel.org

Provide a stub function that return 0 and wire up the static call site
patching to replace the CALL with a single 5 byte instruction that
clears %RAX, the return value register.

The function can be cast to any function pointer type that has a
single %RAX return (including pointers). Also provide a version that
returns an int for convenience. We are clearing the entire %RAX register
in any case, whether the return value is 32 or 64 bits, since %RAX is
always a scratch register anyway.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-2-frederic@kernel.org

Some static call declarations are going to be needed on low level header
files. Move the necessary material to the dedicated static call types
header to avoid inclusion dependency hell.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NFrederic Weisbecker <frederic@kernel.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210118141223.123667-4-frederic@kernel.org

The only remaining use of MAX_USER_PRIO (and USER_PRIO) is the
SCALE_PRIO() definition in the PowerPC Cell architecture's Synergistic
Processor Unit (SPU) scheduler. TASK_USER_PRIO isn't used anymore.

Commit fe443ef2 ("[POWERPC] spusched: Dynamic timeslicing for
SCHED_OTHER") copied SCALE_PRIO() from the task scheduler in v2.6.23.

Commit a4ec24b4 ("sched: tidy up SCHED_RR") removed it from the task
scheduler in v2.6.24.

Commit 3ee237dd ("sched/prio: Add 3 macros of MAX_NICE, MIN_NICE and
NICE_WIDTH in prio.h") introduced NICE_WIDTH much later.

With:

  MAX_USER_PRIO = USER_PRIO(MAX_PRIO)

                = MAX_PRIO - MAX_RT_PRIO

       MAX_PRIO = MAX_RT_PRIO + NICE_WIDTH

  MAX_USER_PRIO = MAX_RT_PRIO + NICE_WIDTH - MAX_RT_PRIO

  MAX_USER_PRIO = NICE_WIDTH

MAX_USER_PRIO can be replaced by NICE_WIDTH to be able to remove all the
{*_}USER_PRIO defines.
Signed-off-by: NDietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210128131040.296856-3-dietmar.eggemann@arm.com

Commit d46523ea ("[PATCH] fix MAX_USER_RT_PRIO and MAX_RT_PRIO")
was introduced due to a a small time period in which the realtime patch
set was using different values for MAX_USER_RT_PRIO and MAX_RT_PRIO.

This is no longer true, i.e. now MAX_RT_PRIO == MAX_USER_RT_PRIO.

Get rid of MAX_USER_RT_PRIO and make everything use MAX_RT_PRIO
instead.
Signed-off-by: NDietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20210128131040.296856-2-dietmar.eggemann@arm.com

Reduce rbtree boiler plate by using the new helpers.

One noteworthy change is unification of the various (partial) compare
functions. We construct a subtree match by forcing the sub-order to
always match, see __group_cmp().

Due to 'const' we had to touch cgroup_id().
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavidlohr Bueso <dbueso@suse.de>

Reduce rbtree boiler plate by using the new helpers.

Make rb_add_cached() / rb_erase_cached() return a pointer to the
leftmost node to aid in updating additional state.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NDavidlohr Bueso <dbueso@suse.de>

I've always been bothered by the endless (fragile) boilerplate for
rbtree, and I recently wrote some rbtree helpers for objtool and
figured I should lift them into the kernel and use them more widely.

Provide:

partial-order; less() based:
 - rb_add(): add a new entry to the rbtree
 - rb_add_cached(): like rb_add(), but for a rb_root_cached

total-order; cmp() based:
 - rb_find(): find an entry in an rbtree
 - rb_find_add(): find an entry, and add if not found

 - rb_find_first(): find the first (leftmost) matching entry
 - rb_next_match(): continue from rb_find_first()
 - rb_for_each(): iterate a sub-tree using the previous two

Inlining and constant propagation should see the compiler inline the
whole thing, including the various compare functions.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Reviewed-by: NMichel Lespinasse <walken@google.com>
Acked-by: NDavidlohr Bueso <dbueso@suse.de>

Prevent netif_tx_disable() running concurrently with dev_watchdog() by
taking the device global xmit lock. Otherwise, the recommended:

	netif_carrier_off(dev);
	netif_tx_disable(dev);

driver shutdown sequence can happen after the watchdog has already
checked carrier, resulting in possible false alarms. This is because
netif_tx_lock() only sets the frozen bit without maintaining the locks
on the individual queues.

Fixes: c3f26a26 ("netdev: Fix lockdep warnings in multiqueue configurations.")
Signed-off-by: NEdwin Peer <edwin.peer@broadcom.com>
Reviewed-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 29915524 ("entry: Drop usage of TIF flags in the generic syscall
code") introduced a bug on architectures using the generic syscall entry
code, in which processes stopped by PTRACE_SYSCALL do not trap on syscall
return after receiving a TIF_SINGLESTEP.

The reason is that the meaning of TIF_SINGLESTEP flag is overloaded to
cause the trap after a system call is executed, but since the above commit,
the syscall call handler only checks for the SYSCALL_WORK flags on the exit
work.

Split the meaning of TIF_SINGLESTEP such that it only means single-step
mode, and create a new type of SYSCALL_WORK to request a trap immediately
after a syscall in single-step mode.  In the current implementation, the
SYSCALL_WORK flag shadows the TIF_SINGLESTEP flag for simplicity.

Update x86 to flip this bit when a tracer enables single stepping.

Fixes: 29915524 ("entry: Drop usage of TIF flags in the generic syscall code")
Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NGabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NKyle Huey <me@kylehuey.com>
Link: https://lore.kernel.org/r/87h7mtc9pr.fsf_-_@collabora.com

Since commit a85a6c86 ("driver core: platform: Clarify that IRQ 0
is invalid"), having a linux-irq with number 0 will trigger a WARN()
when calling platform_get_irq*() to retrieve that linux-irq.

Since [devm_]irq_alloc_desc allocs a single irq and since irq 0 is not used
on some systems, it can return 0, triggering that WARN(). This happens
e.g. on Intel Bay Trail and Cherry Trail devices using the LPE audio engine
for HDMI audio:

 0 is an invalid IRQ number
 WARNING: CPU: 3 PID: 472 at drivers/base/platform.c:238 platform_get_irq_optional+0x108/0x180
 Modules linked in: snd_hdmi_lpe_audio(+) ...

 Call Trace:
  platform_get_irq+0x17/0x30
  hdmi_lpe_audio_probe+0x4a/0x6c0 [snd_hdmi_lpe_audio]

 ---[ end trace ceece38854223a0b ]---

Change the 'from' parameter passed to __[devm_]irq_alloc_descs() by the
[devm_]irq_alloc_desc macros from 0 to 1, so that these macros will no
longer return 0.

Fixes: a85a6c86 ("driver core: platform: Clarify that IRQ 0 is invalid")
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20201221185647.226146-1-hdegoede@redhat.com

Patch series "kasan: Fix metadata detection for KASAN_HW_TAGS", v5.

With the introduction of KASAN_HW_TAGS, kasan_report() currently assumes
that every location in memory has valid metadata associated.  This is
due to the fact that addr_has_metadata() returns always true.

As a consequence of this, an invalid address (e.g.  NULL pointer
address) passed to kasan_report() when KASAN_HW_TAGS is enabled, leads
to a kernel panic.

Example below, based on arm64:

   BUG: KASAN: invalid-access in 0x0
   Read at addr 0000000000000000 by task swapper/0/1
   Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
   Mem abort info:
     ESR = 0x96000004
     EC = 0x25: DABT (current EL), IL = 32 bits
     SET = 0, FnV = 0
     EA = 0, S1PTW = 0
   Data abort info:
     ISV = 0, ISS = 0x00000004
     CM = 0, WnR = 0

  ...

   Call trace:
    mte_get_mem_tag+0x24/0x40
    kasan_report+0x1a4/0x410
    alsa_sound_last_init+0x8c/0xa4
    do_one_initcall+0x50/0x1b0
    kernel_init_freeable+0x1d4/0x23c
    kernel_init+0x14/0x118
    ret_from_fork+0x10/0x34
   Code: d65f03c0 9000f021 f9428021 b6cfff61 (d9600000)
   ---[ end trace 377c8bb45bdd3a1a ]---
   hrtimer: interrupt took 48694256 ns
   note: swapper/0[1] exited with preempt_count 1
   Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
   SMP: stopping secondary CPUs
   Kernel Offset: 0x35abaf140000 from 0xffff800010000000
   PHYS_OFFSET: 0x40000000
   CPU features: 0x0a7e0152,61c0a030
   Memory Limit: none
   ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---

This series fixes the behavior of addr_has_metadata() that now returns
true only when the address is valid.

This patch (of 2):

With the introduction of KASAN_HW_TAGS, kasan_report() accesses the
metadata only when addr_has_metadata() succeeds.

Add a comment to make sure that the preconditions to the function are
explicitly clarified.

Link: https://lkml.kernel.org/r/20210126134409.47894-1-vincenzo.frascino@arm.com
Link: https://lkml.kernel.org/r/20210126134409.47894-2-vincenzo.frascino@arm.comSigned-off-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: NAndrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When VM_MAP_PUT_PAGES was added, it was defined with the same value as
VM_FLUSH_RESET_PERMS.  This doesn't seem like it will cause any big
functional problems other than some excess flushing for VM_MAP_PUT_PAGES
allocations.

Redefine VM_MAP_PUT_PAGES to have its own value.  Also, rearrange things
so flags are less likely to be missed in the future.

Link: https://lkml.kernel.org/r/20210122233706.9304-1-rick.p.edgecombe@intel.com
Fixes: b944afc9 ("mm: add a VM_MAP_PUT_PAGES flag for vmap")
Signed-off-by: NRick Edgecombe <rick.p.edgecombe@intel.com>
Suggested-by: NMatthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Axtens <dja@axtens.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If a new hugetlb page is allocated during fallocate it will not be
marked as active (set_page_huge_active) which will result in a later
isolate_huge_page failure when the page migration code would like to
move that page.  Such a failure would be unexpected and wrong.

Only export set_page_huge_active, just leave clear_page_huge_active as
static.  Because there are no external users.

Link: https://lkml.kernel.org/r/20210115124942.46403-3-songmuchun@bytedance.com
Fixes: 70c3547e (hugetlbfs: add hugetlbfs_fallocate())
Signed-off-by: NMuchun Song <songmuchun@bytedance.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: NMike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: NOscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When iteratively computing a checksum with csum_block_add, track the
offset "pos" to correctly rotate in csum_block_add when offset is odd.

The open coded implementation of skb_copy_and_csum_datagram did this.
With the switch to __skb_datagram_iter calling csum_and_copy_to_iter,
pos was reinitialized to 0 on each call.

Bring back the pos by passing it along with the csum to the callback.

Changes v1->v2
  - pass csum value, instead of csump pointer (Alexander Duyck)

Link: https://lore.kernel.org/netdev/20210128152353.GB27281@optiplex/
Fixes: 950fcaec ("datagram: consolidate datagram copy to iter helpers")
Reported-by: NOliver Graute <oliver.graute@gmail.com>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Reviewed-by: NAlexander Duyck <alexanderduyck@fb.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20210203192952.1849843-1-willemdebruijn.kernel@gmail.comSigned-off-by: NJakub Kicinski <kuba@kernel.org>

The dev_iommu_priv_get() needs a similar check to
dev_iommu_fwspec_get() to make sure no NULL-ptr is dereferenced.

Fixes: 05a0542b ("iommu/amd: Store dev_data as device iommu private data")
Cc: stable@vger.kernel.org	# v5.8+
Link: https://lore.kernel.org/r/20210202145419.29143-1-joro@8bytes.org
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=211241Signed-off-by: NJoerg Roedel <jroedel@suse.de>

When executing a tracepoint, the tracepoint's func is dereferenced twice -
in __DO_TRACE() (where the returned pointer is checked) and later on in
__traceiter_##_name where the returned pointer is dereferenced without
checking which leads to races against tracepoint_removal_sync() and
crashes.

This adds a check before referencing the pointer in tracepoint_ptr_deref.

Link: https://lkml.kernel.org/r/20210202072326.120557-1-aik@ozlabs.ru

Cc: stable@vger.kernel.org
Fixes: d25e37d8 ("tracepoint: Optimize using static_call()")
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

When MSI_FLAG_ACTIVATE_EARLY is set (which is the case for PCI),
__msi_domain_alloc_irqs() performs the activation of the interrupt (which
in the case of PCI results in the endpoint being programmed) as soon as the
interrupt is allocated.

But it appears that this is only done for the first vector, introducing an
inconsistent behaviour for PCI Multi-MSI.

Fix it by iterating over the number of vectors allocated to each MSI
descriptor. This is easily achieved by introducing a new
"for_each_msi_vector" iterator, together with a tiny bit of refactoring.

Fixes: f3b0946d ("genirq/msi: Make sure PCI MSIs are activated early")
Reported-by: NShameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: NMarc Zyngier <maz@kernel.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NShameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210123122759.1781359-1-maz@kernel.org

Fix kprobe_on_func_entry() returns error code instead of false so that
register_kretprobe() can return an appropriate error code.

append_trace_kprobe() expects the kprobe registration returns -ENOENT
when the target symbol is not found, and it checks whether the target
module is unloaded or not. If the target module doesn't exist, it
defers to probe the target symbol until the module is loaded.

However, since register_kretprobe() returns -EINVAL instead of -ENOENT
in that case, it always fail on putting the kretprobe event on unloaded
modules. e.g.

Kprobe event:
/sys/kernel/debug/tracing # echo p xfs:xfs_end_io >> kprobe_events
[   16.515574] trace_kprobe: This probe might be able to register after target module is loaded. Continue.

Kretprobe event: (p -> r)
/sys/kernel/debug/tracing # echo r xfs:xfs_end_io >> kprobe_events
sh: write error: Invalid argument
/sys/kernel/debug/tracing # cat error_log
[   41.122514] trace_kprobe: error: Failed to register probe event
  Command: r xfs:xfs_end_io
             ^

To fix this bug, change kprobe_on_func_entry() to detect symbol lookup
failure and return -ENOENT in that case. Otherwise it returns -EINVAL
or 0 (succeeded, given address is on the entry).

Link: https://lkml.kernel.org/r/161176187132.1067016.8118042342894378981.stgit@devnote2

Cc: stable@vger.kernel.org
Fixes: 59158ec4 ("tracing/kprobes: Check the probe on unloaded module correctly")
Reported-by: NJianlin Lv <Jianlin.Lv@arm.com>
Signed-off-by: NMasami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

The comment says:
  /* task_struct member predeclarations (sorted alphabetically): */

So move io_uring_task where it belongs (alphabetically).
Signed-off-by: NPeter Oskolkov <posk@google.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210126193449.487547-1-posk@google.com

The deduplicating sort in sched_init_numa() assumes that the first line in
the distance table contains all unique values in the entire table. I've
been trying to pen what this exactly means for the topology, but it's not
straightforward. For instance, topology.c uses this example:

  node   0   1   2   3
    0:  10  20  20  30
    1:  20  10  20  20
    2:  20  20  10  20
    3:  30  20  20  10

  0 ----- 1
  |     / |
  |   /   |
  | /     |
  2 ----- 3

Which works out just fine. However, if we swap nodes 0 and 1:

  1 ----- 0
  |     / |
  |   /   |
  | /     |
  2 ----- 3

we get this distance table:

  node   0  1  2  3
    0:  10 20 20 20
    1:  20 10 20 30
    2:  20 20 10 20
    3:  20 30 20 10

Which breaks the deduplicating sort (non-representative first line). In
this case this would just be a renumbering exercise, but it so happens that
we can have a deduplicating sort that goes through the whole table in O(n²)
at the extra cost of a temporary memory allocation (i.e. any form of set).

The ACPI spec (SLIT) mentions distances are encoded on 8 bits. Following
this, implement the set as a 256-bits bitmap. Should this not be
satisfactory (i.e. we want to support 32-bit values), then we'll have to go
for some other sparse set implementation.

This has the added benefit of letting us allocate just the right amount of
memory for sched_domains_numa_distance[], rather than an arbitrary
(nr_node_ids + 1).

Note: DT binding equivalent (distance-map) decodes distances as 32-bit
values.
Signed-off-by: NValentin Schneider <valentin.schneider@arm.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210122123943.1217-2-valentin.schneider@arm.com

Remove duplicated helper functions to parse opaque XDR objects
and place inside new file net/sunrpc/auth_gss/auth_gss_internal.h.
In the new file carry the license and copyright from the source file
net/sunrpc/auth_gss/auth_gss.c.  Finally, update the comment inside
include/linux/sunrpc/xdr.h since lockd is not the only user of
struct xdr_netobj.
Signed-off-by: NDave Wysochanski <dwysocha@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>

layer to use write_iter. Fix the redirected_tty_write declaration
also in n_tty and change the comparisons to use write_iter instead of
write.

[ Also moved the declaration of redirected_tty_write() to the proper
  location in a header file. The reason for the bug was the bogus extern
  declaration in n_tty.c silently not matching the changed definition in
  tty_io.c, and because it wasn't in a shared header file, there was no
  cross-checking of the declaration.

  Sami noticed because Clang's Control Flow Integrity checking ended up
  incidentally noticing the inconsistent declaration.    - Linus ]

Fixes: 9bb48c82 ("tty: implement write_iter")
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is a need to distinguish geniune per-cpu kthreads from kthreads
that happen to have a single CPU affinity.

Geniune per-cpu kthreads are kthreads that are CPU affine for
correctness, these will obviously have PF_KTHREAD set, but must also
have PF_NO_SETAFFINITY set, lest userspace modify their affinity and
ruins things.

However, these two things are not sufficient, PF_NO_SETAFFINITY is
also set on other tasks that have their affinities controlled through
other means, like for instance workqueues.

Therefore another bit is needed; it turns out kthread_create_per_cpu()
already has such a bit: KTHREAD_IS_PER_CPU, which is used to make
kthread_park()/kthread_unpark() work correctly.

Expose this flag and remove the implicit setting of it from
kthread_create_on_cpu(); the io_uring usage of it seems dubious at
best.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: NValentin Schneider <valentin.schneider@arm.com>
Tested-by: NValentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20210121103506.557620262@infradead.org

The device link device's name was of the form:
<supplier-dev-name>--<consumer-dev-name>

This can cause name collision as reported here [1] as device names are
not globally unique. Since device names have to be unique within the
bus/class, add the bus/class name as a prefix to the device names used to
construct the device link device name.

So the devuce link device's name will be of the form:
<supplier-bus-name>:<supplier-dev-name>--<consumer-bus-name>:<consumer-dev-name>

[1] - https://lore.kernel.org/lkml/20201229033440.32142-1-michael@walle.cc/

Fixes: 287905e6 ("driver core: Expose device link details in sysfs")
Cc: stable@vger.kernel.org
Reported-by: NMichael Walle <michael@walle.cc>
Tested-by: NMichael Walle <michael@walle.cc>
Signed-off-by: NSaravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210110175408.1465657-1-saravanak@google.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add missing stubs to regulator/consumer.h in order to fix COMPILE_TEST
of the kernel. In particular this should fix compile-testing of OPP core
because of a missing stub for regulator_sync_voltage().
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NDmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20210120205844.12658-1-digetx@gmail.comSigned-off-by: NMark Brown <broonie@kernel.org>

RTL8156 sends notifications about every 32ms.
Only display/log notifications when something changes.

This issue has been reported by others:
	https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1832472
	https://lkml.org/lkml/2020/8/27/1083

...
[785962.779840] usb 1-1: new high-speed USB device number 5 using xhci_hcd
[785962.929944] usb 1-1: New USB device found, idVendor=0bda, idProduct=8156, bcdDevice=30.00
[785962.929949] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=6
[785962.929952] usb 1-1: Product: USB 10/100/1G/2.5G LAN
[785962.929954] usb 1-1: Manufacturer: Realtek
[785962.929956] usb 1-1: SerialNumber: 000000001
[785962.991755] usbcore: registered new interface driver cdc_ether
[785963.017068] cdc_ncm 1-1:2.0: MAC-Address: 00:24:27:88:08:15
[785963.017072] cdc_ncm 1-1:2.0: setting rx_max = 16384
[785963.017169] cdc_ncm 1-1:2.0: setting tx_max = 16384
[785963.017682] cdc_ncm 1-1:2.0 usb0: register 'cdc_ncm' at usb-0000:00:14.0-1, CDC NCM, 00:24:27:88:08:15
[785963.019211] usbcore: registered new interface driver cdc_ncm
[785963.023856] usbcore: registered new interface driver cdc_wdm
[785963.025461] usbcore: registered new interface driver cdc_mbim
[785963.038824] cdc_ncm 1-1:2.0 enx002427880815: renamed from usb0
[785963.089586] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected
[785963.121673] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected
[785963.153682] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected
...

This is about 2KB per second and will overwrite all contents of a 1MB
dmesg buffer in under 10 minutes rendering them useless for debugging
many kernel problems.

This is also an extra 180 MB/day in /var/logs (or 1GB per week) rendering
the majority of those logs useless too.

When the link is up (expected state), spew amount is >2x higher:
...
[786139.600992] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected
[786139.632997] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink
[786139.665097] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected
[786139.697100] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink
[786139.729094] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected
[786139.761108] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink
...

Chrome OS cannot support RTL8156 until this is fixed.
Signed-off-by: NGrant Grundler <grundler@chromium.org>
Reviewed-by: NHayes Wang <hayeswang@realtek.com>
Link: https://lore.kernel.org/r/20210120011208.3768105-1-grundler@chromium.orgSigned-off-by: NJakub Kicinski <kuba@kernel.org>

This reverts commit fbdd0049.

Due to commit in fixes tag, netdevice events were received only in one net
namespace of mlx5_core_dev. Due to this when netdevice events arrive in
net namespace other than net namespace of mlx5_core_dev, they are missed.

This results in empty GID table due to RDMA device being detached from its
net device.

Hence, revert back to receive netdevice events in all net namespaces to
restore back RDMA functionality in non init_net net namespace. The
deadlock will have to be addressed in another patch.

Fixes: fbdd0049 ("RDMA/mlx5: Fix devlink deadlock on net namespace deletion")
Link: https://lore.kernel.org/r/20210117092633.10690-1-leon@kernel.orgSigned-off-by: NParav Pandit <parav@nvidia.com>
Signed-off-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>

Export mdiobb_read() and mdiobb_write(), so Ethernet controller drivers
can call them from their MDIO read/write wrappers.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Tested-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

Since NVMe v1.4 the Controller Memory Buffer must be explicitly enabled
by the host.
Signed-off-by: NKlaus Jensen <k.jensen@samsung.com>
[hch: avoid a local variable and add a comment]
Signed-off-by: NChristoph Hellwig <hch@lst.de>

GCC versions >= 4.9 and < 5.1 have been shown to emit memory references
beyond the stack pointer, resulting in memory corruption if an interrupt
is taken after the stack pointer has been adjusted but before the
reference has been executed. This leads to subtle, infrequent data
corruption such as the EXT4 problems reported by Russell King at the
link below.

Life is too short for buggy compilers, so raise the minimum GCC version
required by arm64 to 5.1.
Reported-by: NRussell King <linux@armlinux.org.uk>
Suggested-by: NArnd Bergmann <arnd@kernel.org>
Signed-off-by: NWill Deacon <will@kernel.org>
Tested-by: NNathan Chancellor <natechancellor@gmail.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NNathan Chancellor <natechancellor@gmail.com>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20210105154726.GD1551@shell.armlinux.org.uk
Link: https://lore.kernel.org/r/20210112224832.10980-1-will@kernel.orgSigned-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Arnd found a randconfig that produces the warning:

  arch/x86/entry/thunk_64.o: warning: objtool: missing symbol for insn at
  offset 0x3e

when building with LLVM_IAS=1 (Clang's integrated assembler). Josh
notes:

  With the LLVM assembler not generating section symbols, objtool has no
  way to reference this code when it generates ORC unwinder entries,
  because this code is outside of any ELF function.

  The limitation now being imposed by objtool is that all code must be
  contained in an ELF symbol.  And .L symbols don't create such symbols.

  So basically, you can use an .L symbol *inside* a function or a code
  segment, you just can't use the .L symbol to contain the code using a
  SYM_*_START/END annotation pair.

Fangrui notes that this optimization is helpful for reducing image size
when compiling with -ffunction-sections and -fdata-sections. I have
observed on the order of tens of thousands of symbols for the kernel
images built with those flags.

A patch has been authored against GNU binutils to match this behavior
of not generating unused section symbols ([1]), so this will
also become a problem for users of GNU binutils once they upgrade to 2.36.

Omit the .L prefix on a label so that the assembler will emit an entry
into the symbol table for the label, with STB_LOCAL binding. This
enables objtool to generate proper unwind info here with LLVM_IAS=1 or
GNU binutils 2.36+.

 [ bp: Massage commit message. ]
Reported-by: NArnd Bergmann <arnd@arndb.de>
Suggested-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Suggested-by: NBorislav Petkov <bp@alien8.de>
Suggested-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20210112194625.4181814-1-ndesaulniers@google.com
Link: https://github.com/ClangBuiltLinux/linux/issues/1209
Link: https://reviews.llvm.org/D93783
Link: https://sourceware.org/binutils/docs/as/Symbol-Names.html
Link: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d1bcae833b32f1408485ce69f844dcd7ded093a8 [1]

There is nothing schedutil specific in schedutil_cpu_util(), rename it
to effective_cpu_util(). Also create and expose another wrapper
sched_cpu_util() which can be used by other parts of the kernel, like
thermal core (that will be done in a later commit).
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/db011961fb3bb8bef1c0eda5cd64564637d3ef31.1607400596.git.viresh.kumar@linaro.org

This reverts commit 367c820e.

lockup_detector_init() makes heavy use of per-cpu variables and must be
called with preemption disabled. Usually, it's handled early during boot
in kernel_init_freeable(), before SMP has been initialised.

Since we do not know whether or not our PMU interrupt can be signalled
as an NMI until considerably later in the boot process, the Arm PMU
driver attempts to re-initialise the lockup detector off the back of a
device_initcall(). Unfortunately, this is called from preemptible
context and results in the following splat:

  | BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
  | caller is debug_smp_processor_id+0x20/0x2c
  | CPU: 2 PID: 1 Comm: swapper/0 Not tainted 5.10.0+ #276
  | Hardware name: linux,dummy-virt (DT)
  | Call trace:
  |   dump_backtrace+0x0/0x3c0
  |   show_stack+0x20/0x6c
  |   dump_stack+0x2f0/0x42c
  |   check_preemption_disabled+0x1cc/0x1dc
  |   debug_smp_processor_id+0x20/0x2c
  |   hardlockup_detector_event_create+0x34/0x18c
  |   hardlockup_detector_perf_init+0x2c/0x134
  |   watchdog_nmi_probe+0x18/0x24
  |   lockup_detector_init+0x44/0xa8
  |   armv8_pmu_driver_init+0x54/0x78
  |   do_one_initcall+0x184/0x43c
  |   kernel_init_freeable+0x368/0x380
  |   kernel_init+0x1c/0x1cc
  |   ret_from_fork+0x10/0x30

Rather than bodge this with raw_smp_processor_id() or randomly disabling
preemption, simply revert the culprit for now until we figure out how to
do this properly.
Reported-by: NLecopzer Chen <lecopzer.chen@mediatek.com>
Signed-off-by: NWill Deacon <will@kernel.org>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20201221162249.3119-1-lecopzer.chen@mediatek.com
Link: https://lore.kernel.org/r/20210112221855.10666-1-will@kernel.orgSigned-off-by: NCatalin Marinas <catalin.marinas@arm.com>

The size of kasan_early_shadow_pte[] now is PTRS_PER_PTE which defined
to 512 for arm.  This means that it only covers the prev Linux pte
entries, but not the HWTABLE pte entries for arm.

The reason it currently works is that the symbol kasan_early_shadow_page
immediately following kasan_early_shadow_pte in memory is page aligned,
which makes kasan_early_shadow_pte look like a 4KB size array.  But we
can't ensure the order is always right with different compiler/linker,
or if more bss symbols are introduced.

We had a test with QEMU + vexpress：put a 512KB-size symbol with
attribute __section(".bss..page_aligned") after kasan_early_shadow_pte,
and poisoned it after kasan_early_init().  Then enabled CONFIG_KASAN, it
failed to boot up.

Link: https://lkml.kernel.org/r/20210109044622.8312-1-hailongliiu@yeah.netSigned-off-by: NHailong Liu <liu.hailong6@zte.com.cn>
Signed-off-by: NZiliang Guo <guo.ziliang@zte.com.cn>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Boot a CONFIG_MEMCG=y kernel with "cgroup_disabled=memory" and you are
met by a series of warnings from the VM_WARN_ON_ONCE_PAGE(!memcg, page)
recently added to the inline mem_cgroup_page_lruvec().

An earlier attempt to place that warning, in mem_cgroup_lruvec(), had
been careful to do so after weeding out the mem_cgroup_disabled() case;
but was itself invalid because of the mem_cgroup_lruvec(NULL, pgdat) in
clear_pgdat_congested() and age_active_anon().

Warning in mem_cgroup_page_lruvec() was once useful in detecting a KSM
charge bug, so may be worth keeping: but skip if mem_cgroup_disabled().

Link: https://lkml.kernel.org/r/alpine.LSU.2.11.2101032056260.1093@eggly.anvils
Fixes: 9a1ac228 ("mm/memcontrol:rewrite mem_cgroup_page_lruvec()")
Signed-off-by: NHugh Dickins <hughd@google.com>
Reviewed-by: NAlex Shi <alex.shi@linux.alibaba.com>
Acked-by: NRoman Gushchin <guro@fb.com>
Acked-by: NChris Down <chris@chrisdown.name>
Reviewed-by: NBaoquan He <bhe@redhat.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Hui Su <sh_def@163.com>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The get_seconds() cleanup seems to have been completed, now it is
time to delete the legacy interface to avoid misuse later.
Signed-off-by: NChunguang Xu <brookxu@tencent.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/1606816351-26900-1-git-send-email-brookxu@tencent.com