This patch adds a few kernel function bpf_kfunc_call_test*() for the
selftest's test_run purpose.  They will be allowed for tc_cls prog.

The selftest calling the kernel function bpf_kfunc_call_test*()
is also added in this patch.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015252.1551395-1-kafai@fb.com

This patch adds support to BPF verifier to allow bpf program calling
kernel function directly.

The use case included in this set is to allow bpf-tcp-cc to directly
call some tcp-cc helper functions (e.g. "tcp_cong_avoid_ai()").  Those
functions have already been used by some kernel tcp-cc implementations.

This set will also allow the bpf-tcp-cc program to directly call the
kernel tcp-cc implementation,  For example, a bpf_dctcp may only want to
implement its own dctcp_cwnd_event() and reuse other dctcp_*() directly
from the kernel tcp_dctcp.c instead of reimplementing (or
copy-and-pasting) them.

The tcp-cc kernel functions mentioned above will be white listed
for the struct_ops bpf-tcp-cc programs to use in a later patch.
The white listed functions are not bounded to a fixed ABI contract.
Those functions have already been used by the existing kernel tcp-cc.
If any of them has changed, both in-tree and out-of-tree kernel tcp-cc
implementations have to be changed.  The same goes for the struct_ops
bpf-tcp-cc programs which have to be adjusted accordingly.

This patch is to make the required changes in the bpf verifier.

First change is in btf.c, it adds a case in "btf_check_func_arg_match()".
When the passed in "btf->kernel_btf == true", it means matching the
verifier regs' states with a kernel function.  This will handle the
PTR_TO_BTF_ID reg.  It also maps PTR_TO_SOCK_COMMON, PTR_TO_SOCKET,
and PTR_TO_TCP_SOCK to its kernel's btf_id.

In the later libbpf patch, the insn calling a kernel function will
look like:

insn->code == (BPF_JMP | BPF_CALL)
insn->src_reg == BPF_PSEUDO_KFUNC_CALL /* <- new in this patch */
insn->imm == func_btf_id /* btf_id of the running kernel */

[ For the future calling function-in-kernel-module support, an array
  of module btf_fds can be passed at the load time and insn->off
  can be used to index into this array. ]

At the early stage of verifier, the verifier will collect all kernel
function calls into "struct bpf_kfunc_desc".  Those
descriptors are stored in "prog->aux->kfunc_tab" and will
be available to the JIT.  Since this "add" operation is similar
to the current "add_subprog()" and looking for the same insn->code,
they are done together in the new "add_subprog_and_kfunc()".

In the "do_check()" stage, the new "check_kfunc_call()" is added
to verify the kernel function call instruction:
1. Ensure the kernel function can be used by a particular BPF_PROG_TYPE.
   A new bpf_verifier_ops "check_kfunc_call" is added to do that.
   The bpf-tcp-cc struct_ops program will implement this function in
   a later patch.
2. Call "btf_check_kfunc_args_match()" to ensure the regs can be
   used as the args of a kernel function.
3. Mark the regs' type, subreg_def, and zext_dst.

At the later do_misc_fixups() stage, the new fixup_kfunc_call()
will replace the insn->imm with the function address (relative
to __bpf_call_base).  If needed, the jit can find the btf_func_model
by calling the new bpf_jit_find_kfunc_model(prog, insn).
With the imm set to the function address, "bpftool prog dump xlated"
will be able to display the kernel function calls the same way as
it displays other bpf helper calls.

gpl_compatible program is required to call kernel function.

This feature currently requires JIT.

The verifier selftests are adjusted because of the changes in
the verbose log in add_subprog_and_kfunc().
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015142.1544736-1-kafai@fb.com

This patch moved the subprog specific logic from
btf_check_func_arg_match() to the new btf_check_subprog_arg_match().
The core logic is left in btf_check_func_arg_match() which
will be reused later to check the kernel function call.

The "if (!btf_type_is_ptr(t))" is checked first to improve the
indentation which will be useful for a later patch.

Some of the "btf_kind_str[]" usages is replaced with the shortcut
"btf_type_str(t)".
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015136.1544504-1-kafai@fb.com

This patch simplifies the linfo freeing logic by combining
"bpf_prog_free_jited_linfo()" and "bpf_prog_free_unused_jited_linfo()"
into the new "bpf_prog_jit_attempt_done()".
It is a prep work for the kernel function call support.  In a later
patch, freeing the kernel function call descriptors will also
be done in the "bpf_prog_jit_attempt_done()".

"bpf_prog_free_linfo()" is removed since it is only called by
"__bpf_prog_put_noref()".  The kvfree() are directly called
instead.

It also takes this chance to s/kcalloc/kvcalloc/ for the jited_linfo
allocation.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210325015130.1544323-1-kafai@fb.com

Jiri Olsa reported a bug ([1]) in kernel where cgroup local
storage pointer may be NULL in bpf_get_local_storage() helper.
There are two issues uncovered by this bug:
  (1). kprobe or tracepoint prog incorrectly sets cgroup local storage
       before prog run,
  (2). due to change from preempt_disable to migrate_disable,
       preemption is possible and percpu storage might be overwritten
       by other tasks.

This issue (1) is fixed in [2]. This patch tried to address issue (2).
The following shows how things can go wrong:
  task 1:   bpf_cgroup_storage_set() for percpu local storage
         preemption happens
  task 2:   bpf_cgroup_storage_set() for percpu local storage
         preemption happens
  task 1:   run bpf program

task 1 will effectively use the percpu local storage setting by task 2
which will be either NULL or incorrect ones.

Instead of just one common local storage per cpu, this patch fixed
the issue by permitting 8 local storages per cpu and each local
storage is identified by a task_struct pointer. This way, we
allow at most 8 nested preemption between bpf_cgroup_storage_set()
and bpf_cgroup_storage_unset(). The percpu local storage slot
is released (calling bpf_cgroup_storage_unset()) by the same task
after bpf program finished running.
bpf_test_run() is also fixed to use the new bpf_cgroup_storage_set()
interface.

The patch is tested on top of [2] with reproducer in [1].
Without this patch, kernel will emit error in 2-3 minutes.
With this patch, after one hour, still no error.

 [1] https://lore.kernel.org/bpf/CAKH8qBuXCfUz=w8L+Fj74OaUpbosO29niYwTki7e3Ag044_aww@mail.gmail.com/T
 [2] https://lore.kernel.org/bpf/20210309185028.3763817-1-yhs@fb.comSigned-off-by: NYonghong Song <yhs@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NRoman Gushchin <guro@fb.com>
Link: https://lore.kernel.org/bpf/20210323055146.3334476-1-yhs@fb.com

Trivial fix.
Signed-off-by: NRicardo Ribalda <ribalda@chromium.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210318202223.164873-8-ribalda@chromium.org

Commit 34dc2efb ("memblock: fix section mismatch warning") marked
memblock_bottom_up() and memblock_set_bottom_up() as __init, but they
could be referenced from non-init functions like
memblock_find_in_range_node() on architectures that enable
CONFIG_ARCH_KEEP_MEMBLOCK.

For such builds kernel test robot reports:

   WARNING: modpost: vmlinux.o(.text+0x74fea4): Section mismatch in reference from the function memblock_find_in_range_node() to the function .init.text:memblock_bottom_up()
   The function memblock_find_in_range_node() references the function __init memblock_bottom_up().
   This is often because memblock_find_in_range_node lacks a __init  annotation or the annotation of memblock_bottom_up is wrong.

Replace __init annotations with __init_memblock annotations so that the
appropriate section will be selected depending on
CONFIG_ARCH_KEEP_MEMBLOCK.

Link: https://lore.kernel.org/lkml/202103160133.UzhgY0wt-lkp@intel.com
Link: https://lkml.kernel.org/r/20210316171347.14084-1-rppt@kernel.org
Fixes: 34dc2efb ("memblock: fix section mismatch warning")
Signed-off-by: NMike Rapoport <rppt@linux.ibm.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Reported-by: Nkernel test robot <lkp@intel.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Acked-by: NNick Desaulniers <ndesaulniers@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If one or more notifiers fails .invalidate_range_start(), invoke
.invalidate_range_end() for "all" notifiers.  If there are multiple
notifiers, those that did not fail are expecting _start() and _end() to
be paired, e.g.  KVM's mmu_notifier_count would become imbalanced.
Disallow notifiers that can fail _start() from implementing _end() so
that it's unnecessary to either track which notifiers rejected _start(),
or had already succeeded prior to a failed _start().

Note, the existing behavior of calling _start() on all notifiers even
after a previous notifier failed _start() was an unintented "feature".
Make it canon now that the behavior is depended on for correctness.

As of today, the bug is likely benign:

  1. The only caller of the non-blocking notifier is OOM kill.
  2. The only notifiers that can fail _start() are the i915 and Nouveau
     drivers.
  3. The only notifiers that utilize _end() are the SGI UV GRU driver
     and KVM.
  4. The GRU driver will never coincide with the i195/Nouveau drivers.
  5. An imbalanced kvm->mmu_notifier_count only causes soft lockup in the
     _guest_, and the guest is already doomed due to being an OOM victim.

Fix the bug now to play nice with future usage, e.g.  KVM has a
potential use case for blocking memslot updates in KVM while an
invalidation is in-progress, and failure to unblock would result in said
updates being blocked indefinitely and hanging.

Found by inspection.  Verified by adding a second notifier in KVM that
periodically returns -EAGAIN on non-blockable ranges, triggering OOM,
and observing that KVM exits with an elevated notifier count.

Link: https://lkml.kernel.org/r/20210311180057.1582638-1-seanjc@google.com
Fixes: 93065ac7 ("mm, oom: distinguish blockable mode for mmu notifiers")
Signed-off-by: NSean Christopherson <seanjc@google.com>
Suggested-by: NJason Gunthorpe <jgg@ziepe.ca>
Reviewed-by: NJason Gunthorpe <jgg@nvidia.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ben Gardon <bgardon@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

To allow performing tag checks on page_alloc addresses obtained via
page_address(), tag-based KASAN modes store tags for page_alloc
allocations in page->flags.

Currently, the default tag value stored in page->flags is 0x00.
Therefore, page_address() returns a 0x00ffff...  address for pages that
were not allocated via page_alloc.

This might cause problems.  A particular case we encountered is a
conflict with KFENCE.  If a KFENCE-allocated slab object is being freed
via kfree(page_address(page) + offset), the address passed to kfree()
will get tagged with 0x00 (as slab pages keep the default per-page
tags).  This leads to is_kfence_address() check failing, and a KFENCE
object ending up in normal slab freelist, which causes memory
corruptions.

This patch changes the way KASAN stores tag in page-flags: they are now
stored xor'ed with 0xff.  This way, KASAN doesn't need to initialize
per-page flags for every created page, which might be slow.

With this change, page_address() returns natively-tagged (with 0xff)
pointers for pages that didn't have tags set explicitly.

This patch fixes the encountered conflict with KFENCE and prevents more
similar issues that can occur in the future.

Link: https://lkml.kernel.org/r/1a41abb11c51b264511d9e71c303bb16d5cb367b.1615475452.git.andreyknvl@google.com
Fixes: 2813b9c0 ("kasan, mm, arm64: tag non slab memory allocated via pagealloc")
Signed-off-by: NAndrey Konovalov <andreyknvl@google.com>
Reviewed-by: NMarco Elver <elver@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The current implementation of hugetlb_cgroup for shared mappings could
have different behavior.  Consider the following two scenarios:

 1.Assume initial css reference count of hugetlb_cgroup is 1:
  1.1 Call hugetlb_reserve_pages with from = 1, to = 2. So css reference
      count is 2 associated with 1 file_region.
  1.2 Call hugetlb_reserve_pages with from = 2, to = 3. So css reference
      count is 3 associated with 2 file_region.
  1.3 coalesce_file_region will coalesce these two file_regions into
      one. So css reference count is 3 associated with 1 file_region
      now.

 2.Assume initial css reference count of hugetlb_cgroup is 1 again:
  2.1 Call hugetlb_reserve_pages with from = 1, to = 3. So css reference
      count is 2 associated with 1 file_region.

Therefore, we might have one file_region while holding one or more css
reference counts. This inconsistency could lead to imbalanced css_get()
and css_put() pair. If we do css_put one by one (i.g. hole punch case),
scenario 2 would put one more css reference. If we do css_put all
together (i.g. truncate case), scenario 1 will leak one css reference.

The imbalanced css_get() and css_put() pair would result in a non-zero
reference when we try to destroy the hugetlb cgroup. The hugetlb cgroup
directory is removed __but__ associated resource is not freed. This
might result in OOM or can not create a new hugetlb cgroup in a busy
workload ultimately.

In order to fix this, we have to make sure that one file_region must
hold exactly one css reference. So in coalesce_file_region case, we
should release one css reference before coalescence. Also only put css
reference when the entire file_region is removed.

The last thing to note is that the caller of region_add() will only hold
one reference to h_cg->css for the whole contiguous reservation region.
But this area might be scattered when there are already some
file_regions reside in it. As a result, many file_regions may share only
one h_cg->css reference. In order to ensure that one file_region must
hold exactly one css reference, we should do css_get() for each
file_region and release the reference held by caller when they are done.

[linmiaohe@huawei.com: fix imbalanced css_get and css_put pair for shared mappings]
  Link: https://lkml.kernel.org/r/20210316023002.53921-1-linmiaohe@huawei.com

Link: https://lkml.kernel.org/r/20210301120540.37076-1-linmiaohe@huawei.com
Fixes: 075a61d0 ("hugetlb_cgroup: add accounting for shared mappings")
Reported-by: kernel test robot <lkp@intel.com> (auto build test ERROR)
Signed-off-by: NMiaohe Lin <linmiaohe@huawei.com>
Reviewed-by: NMike Kravetz <mike.kravetz@oracle.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Wanpeng Li <liwp.linux@gmail.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In order to discover whether remote station supports frame preemption,
local station sends verify mPacket and expects response mPacket in
return from the remote station.

So, we add the functions to send and handle event when verify mPacket
and response mPacket are exchanged between the networked stations.

The mechanism to handle different FPE states between local and remote
station (link partner) is implemented using workqueue which starts a
task each time there is some sign of verify & response mPacket exchange
as check in FPE IRQ event. The task retries couple of times to try to
spot the states that both stations are ready to enter FPE ON. This allows
different end points to enable FPE at different time and verify-response
mPacket can happen asynchronously. Ultimately, the task will only turn
FPE ON when local station have both exchange response in both directions.

Thanks to Voon Weifeng for implementing the core functions for detecting
FPE events and send mPacket and phylink related change.
Signed-off-by: NOng Boon Leong <boon.leong.ong@intel.com>
Co-developed-by: NVoon Weifeng <weifeng.voon@intel.com>
Signed-off-by: NVoon Weifeng <weifeng.voon@intel.com>
Co-developed-by: NTan Tee Min <tee.min.tan@intel.com>
Signed-off-by: NTan Tee Min <tee.min.tan@intel.com>
Co-developed-by: NMohammad Athari Bin Ismail <mohammad.athari.ismail@intel.com>
Signed-off-by: NMohammad Athari Bin Ismail <mohammad.athari.ismail@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add generic code to enable C45 PHY loopback into the common phy-c45.c
file. This will allow C45 PHY drivers aceess this by setting
.set_loopback.
Suggested-by: NHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: NWong Vee Khee <vee.khee.wong@linux.intel.com>
Reviewed-by: NHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cross timestamping is supported on Integrated Ethernet Controller in
Intel SoC such as EHL and TGL with Always Running Timer.

The hardware cross-timestamp result is made available to
applications through the PTP_SYS_OFFSET_PRECISE ioctl which calls
stmmac_getcrosststamp().

Device time is stored in the MAC Auxiliary register. The 64-bit System
time (ART timestamp) is stored in registers that are only addressable
by using MDIO space.
Signed-off-by: NTan Tee Min <tee.min.tan@intel.com>
Co-developed-by: NWong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: NWong Vee Khee <vee.khee.wong@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The switch might have already added the VLAN tag through PVID hardware
offload. Keep this extra VLAN in the flowtable but skip it on egress.
Signed-off-by: NFelix Fietkau <nbd@nbd.name>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add .ndo_fill_forward_path for dsa slave port devices
Signed-off-by: NFelix Fietkau <nbd@nbd.name>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass on the PPPoE session ID, destination hardware address and the real
device.
Signed-off-by: NFelix Fietkau <nbd@nbd.name>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Depending on the VLAN settings of the bridge and the port, the bridge can
either add or remove a tag. When vlan filtering is enabled, the fdb lookup
also needs to know the VLAN tag/proto for the destination address
To provide this, keep track of the stack of VLAN tags for the path in the
lookup context
Signed-off-by: NFelix Fietkau <nbd@nbd.name>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add .ndo_fill_forward_path for bridge devices.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add .ndo_fill_forward_path for vlan devices.

For instance, assuming the following topology:

                   IP forwarding
                  /             \
            eth0.100             eth0
            |
            eth0
            .
            .
            .
           ethX
     ab:cd:ef:ab:cd:ef

For packets going through IP forwarding to eth0.100 whose destination
MAC address is ab:cd:ef:ab:cd:ef, dev_fill_forward_path() provides the
following path:

        eth0.100 -> eth0
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds dev_fill_forward_path() which resolves the path to reach
the real netdevice from the IP forwarding side. This function takes as
input the netdevice and the destination hardware address and it walks
down the devices calling .ndo_fill_forward_path() for each device until
the real device is found.

For instance, assuming the following topology:

               IP forwarding
              /             \
           br0              eth0
           / \
       eth1  eth2
        .
        .
        .
       ethX
 ab:cd:ef:ab:cd:ef

where eth1 and eth2 are bridge ports and eth0 provides WAN connectivity.
ethX is the interface in another box which is connected to the eth1
bridge port.

For packets going through IP forwarding to br0 whose destination MAC
address is ab:cd:ef:ab:cd:ef, dev_fill_forward_path() provides the
following path:

	br0 -> eth1

.ndo_fill_forward_path for br0 looks up at the FDB for the bridge port
from the destination MAC address to get the bridge port eth1.

This information allows to create a fast path that bypasses the classic
bridge and IP forwarding paths, so packets go directly from the bridge
port eth1 to eth0 (wan interface) and vice versa.

             fast path
      .------------------------.
     /                          \
    |           IP forwarding   |
    |          /             \  \/
    |       br0               eth0
    .       / \
     -> eth1  eth2
        .
        .
        .
       ethX
 ab:cd:ef:ab:cd:ef
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

netdev_wait_allrefs() issues a warning if refcount does not drop to 0
after 10 seconds. While 10 second wait generally should not happen
under normal workload in normal environment, it seems to fire falsely
very often during fuzzing and/or in qemu emulation (~10x slower).
At least it's not possible to understand if it's really a false
positive or not. Automated testing generally bumps all timeouts
to very high values to avoid flake failures.
Add net.core.netdev_unregister_timeout_secs sysctl to make
the timeout configurable for automated testing systems.
Lowering the timeout may also be useful for e.g. manual bisection.
The default value matches the current behavior.
Signed-off-by: NDmitry Vyukov <dvyukov@google.com>
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=211877
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently this simple setup with DSA:

ip link add br0 type bridge vlan_filtering 1
ip link add bond0 type bond
ip link set bond0 master br0
ip link set swp0 master bond0

will not work because the bridge has created the PVID in br_add_if ->
nbp_vlan_init, and it has notified switchdev of the existence of VLAN 1,
but that was too early, since swp0 was not yet a lower of bond0, so it
had no reason to act upon that notification.

We need a helper in the bridge to replay the switchdev VLAN objects that
were notified since the bridge port creation, because some of them may
have been missed.

As opposed to the br_mdb_replay function, the vg->vlan_list write side
protection is offered by the rtnl_mutex which is sleepable, so we don't
need to queue up the objects in atomic context, we can replay them right
away.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a switchdev port starts offloading a LAG that is already in a
bridge and has an FDB entry pointing to it:

ip link set bond0 master br0
bridge fdb add dev bond0 00:01:02:03:04:05 master static
ip link set swp0 master bond0

the switchdev driver will have no idea that this FDB entry is there,
because it missed the switchdev event emitted at its creation.

Ido Schimmel pointed this out during a discussion about challenges with
switchdev offloading of stacked interfaces between the physical port and
the bridge, and recommended to just catch that condition and deny the
CHANGEUPPER event:
https://lore.kernel.org/netdev/20210210105949.GB287766@shredder.lan/

But in fact, we might need to deal with the hard thing anyway, which is
to replay all FDB addresses relevant to this port, because it isn't just
static FDB entries, but also local addresses (ones that are not
forwarded but terminated by the bridge). There, we can't just say 'oh
yeah, there was an upper already so I'm not joining that'.

So, similar to the logic for replaying MDB entries, add a function that
must be called by individual switchdev drivers and replays local FDB
entries as well as ones pointing towards a bridge port. This time, we
use the atomic switchdev notifier block, since that's what FDB entries
expect for some reason.
Reported-by: NIdo Schimmel <idosch@idosch.org>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I have a system with DSA ports, and udhcpcd is configured to bring
interfaces up as soon as they are created.

I create a bridge as follows:

ip link add br0 type bridge

As soon as I create the bridge and udhcpcd brings it up, I also have
avahi which automatically starts sending IPv6 packets to advertise some
local services, and because of that, the br0 bridge joins the following
IPv6 groups due to the code path detailed below:

33:33:ff:6d:c1:9c vid 0
33:33:00:00:00:6a vid 0
33:33:00:00:00:fb vid 0

br_dev_xmit
-> br_multicast_rcv
   -> br_ip6_multicast_add_group
      -> __br_multicast_add_group
         -> br_multicast_host_join
            -> br_mdb_notify

This is all fine, but inside br_mdb_notify we have br_mdb_switchdev_host
hooked up, and switchdev will attempt to offload the host joined groups
to an empty list of ports. Of course nobody offloads them.

Then when we add a port to br0:

ip link set swp0 master br0

the bridge doesn't replay the host-joined MDB entries from br_add_if,
and eventually the host joined addresses expire, and a switchdev
notification for deleting it is emitted, but surprise, the original
addition was already completely missed.

The strategy to address this problem is to replay the MDB entries (both
the port ones and the host joined ones) when the new port joins the
bridge, similar to what vxlan_fdb_replay does (in that case, its FDB can
be populated and only then attached to a bridge that you offload).
However there are 2 possibilities: the addresses can be 'pushed' by the
bridge into the port, or the port can 'pull' them from the bridge.

Considering that in the general case, the new port can be really late to
the party, and there may have been many other switchdev ports that
already received the initial notification, we would like to avoid
delivering duplicate events to them, since they might misbehave. And
currently, the bridge calls the entire switchdev notifier chain, whereas
for replaying it should just call the notifier block of the new guy.
But the bridge doesn't know what is the new guy's notifier block, it
just knows where the switchdev notifier chain is. So for simplification,
we make this a driver-initiated pull for now, and the notifier block is
passed as an argument.

To emulate the calling context for mdb objects (deferred and put on the
blocking notifier chain), we must iterate under RCU protection through
the bridge's mdb entries, queue them, and only call them once we're out
of the RCU read-side critical section.

There was some opportunity for reuse between br_mdb_switchdev_host_port,
br_mdb_notify and the newly added br_mdb_queue_one in how the switchdev
mdb object is created, so a helper was created.
Suggested-by: NIdo Schimmel <idosch@idosch.org>
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME attribute is only emitted from:

sysfs/ioctl/netlink
-> br_set_ageing_time
   -> __set_ageing_time

therefore not at bridge port creation time, so:
(a) switchdev drivers have to hardcode the initial value for the address
    ageing time, because they didn't get any notification
(b) that hardcoded value can be out of sync, if the user changes the
    ageing time before enslaving the port to the bridge

We need a helper in the bridge, such that switchdev drivers can query
the current value of the bridge ageing time when they start offloading
it.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NTobias Waldekranz <tobias@waldekranz.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It may happen that we have the following topology with DSA or any other
switchdev driver with LAG offload:

ip link add br0 type bridge stp_state 1
ip link add bond0 type bond
ip link set bond0 master br0
ip link set swp0 master bond0
ip link set swp1 master bond0

STP decides that it should put bond0 into the BLOCKING state, and
that's that. The ports that are actively listening for the switchdev
port attributes emitted for the bond0 bridge port (because they are
offloading it) and have the honor of seeing that switchdev port
attribute can react to it, so we can program swp0 and swp1 into the
BLOCKING state.

But if then we do:

ip link set swp2 master bond0

then as far as the bridge is concerned, nothing has changed: it still
has one bridge port. But this new bridge port will not see any STP state
change notification and will remain FORWARDING, which is how the
standalone code leaves it in.

We need a function in the bridge driver which retrieves the current STP
state, such that drivers can synchronize to it when they may have missed
switchdev events.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NTobias Waldekranz <tobias@waldekranz.com>
Acked-by: NNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is the killable version of wait_on_page_writeback.
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: kafs-testing@auristor.com
cc: linux-afs@lists.infradead.org
cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/20210320054104.1300774-3-willy@infradead.org

Cachefiles was relying on wait_page_key and wait_bit_key being the
same layout, which is fragile.  Now that wait_page_key is exposed in
the pagemap.h header, we can remove that fragility

A comment on the need to maintain structure layout equivalence was added by
Linus[1] and that is no longer applicable.

Fixes: 62906027 ("mm: add PageWaiters indicating tasks are waiting for a page bit")
Signed-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: kafs-testing@auristor.com
cc: linux-cachefs@redhat.com
cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/20210320054104.1300774-2-willy@infradead.org/
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3510ca20ece0150af6b10c77a74ff1b5c198e3e2 [1]

Report the driver name, ASIC ID and the switch name via devlink. This is a
useful information for user space tooling.
Signed-off-by: NKurt Kanzenbach <kurt@kmk-computers.de>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVladimir Oltean <olteanv@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When adding CONFIG_PCPU_DEV_REFCNT, I forgot that the
initial net device refcount was 0.

When CONFIG_PCPU_DEV_REFCNT is not set, this means
the first dev_hold() triggers an illegal refcount
operation (addition on 0)

refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 1 at lib/refcount.c:25 refcount_warn_saturate+0x128/0x1a4

Fix is to change initial (and final) refcount to be 1.

Also add a missing kerneldoc piece, as reported by
Stephen Rothwell.

Fixes: 919067cc ("net: add CONFIG_PCPU_DEV_REFCNT")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NGuenter Roeck <groeck@google.com>
Tested-by: NGuenter Roeck <groeck@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ptype_all and ptype_base are declared in net/core/dev.c as non-static,
because they are used by net-procfs.c too. However, a "make W=1" build
complains that there was no previous declaration of ptype_all and
ptype_base in a header file, so this way of declaring things constitutes
a violation of coding style.

Let's move the extern declarations of ptype_all and ptype_base to the
linux/netdevice.h file, which is included by net-procfs.c too.
Signed-off-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

s/unrequired/"not required"/
s/consme/consume/ .....two different places
s/accros/across/
Signed-off-by: NBhaskar Chowdhury <unixbhaskar@gmail.com>
Acked-by: NIgor Russkikh <irusskikh@marvell.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a function to set the dynamic queue limit minimum value.

Some specific drivers might have legitimate reasons to configure
dql.min_limit to a given value. Typically, this is the case when the
PDU of the protocol is smaller than the packet size to used to
carry those frames to the device.

Concrete example: a CAN (Control Area Network) device with an USB 2.0
interface.  The PDU of classical CAN protocol are roughly 16 bytes but
the USB packet size (which is used to carry the CAN frames to the
device) might be up to 512 bytes.  Wen small traffic burst occurs, BQL
algorithm is not able to immediately adjust and this would result in
having to send many small USB packets (i.e packet of 16 bytes for each
CAN frame). Filling up the USB packet with CAN frames is relatively
fast (small latency issue) but the gain of not having to send several
small USB packets is huge (big throughput increase). In this case,
forcing dql.min_limit to a given value that would allow to stuff the
USB packet is always a win.

This function is to be used by network drivers which are able to prove
through a rationale and through empirical tests on several environment
(with other applications, heavy context switching, virtualization...),
that they constantly reach better performances with a specific
predefined dql.min_limit value with no noticeable latency impact.
Signed-off-by: NVincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The virtual channel is going to be extended to support FDIR and
RSS configure from AVF. New data structures and OP codes will be
added, the patch enable the FDIR part.

To support above advanced AVF feature, we need to figure out
what kind of data structure should be passed from VF to PF to describe
an FDIR rule or RSS config rule. The common part of the requirement is
we need a data structure to represent the input set selection of a rule's
hash key.

An input set selection is a group of fields be selected from one or more
network protocol layers that could be identified as a specific flow.
For example, select dst IP address from an IPv4 header combined with
dst port from the TCP header as the input set for an IPv4/TCP flow.

The patch adds a new data structure virtchnl_proto_hdrs to abstract
a network protocol headers group which is composed of layers of network
protocol header(virtchnl_proto_hdr).

A protocol header contains a 32 bits mask (field_selector) to describe
which fields are selected as input sets, as well as a header type
(enum virtchnl_proto_hdr_type). Each bit is mapped to a field in
enum virtchnl_proto_hdr_field guided by its header type.

+------------+-----------+------------------------------+
|            | Proto Hdr | Header Type A                |
|            |           +------------------------------+
|            |           | BIT 31 | ... | BIT 1 | BIT 0 |
|            |-----------+------------------------------+
|Proto Hdrs  | Proto Hdr | Header Type B                |
|            |           +------------------------------+
|            |           | BIT 31 | ... | BIT 1 | BIT 0 |
|            |-----------+------------------------------+
|            | Proto Hdr | Header Type C                |
|            |           +------------------------------+
|            |           | BIT 31 | ... | BIT 1 | BIT 0 |
|            |-----------+------------------------------+
|            |    ....                                  |
+-------------------------------------------------------+

All fields in enum virtchnl_proto_hdr_fields are grouped with header type
and the value of the first field of a header type is always 32 aligned.

enum proto_hdr_type {
        header_type_A = 0;
        header_type_B = 1;
        ....
}

enum proto_hdr_field {
        /* header type A */
        header_A_field_0 = 0,
        header_A_field_1 = 1,
        header_A_field_2 = 2,
        header_A_field_3 = 3,

        /* header type B */
        header_B_field_0 = 32, // = header_type_B << 5
        header_B_field_0 = 33,
        header_B_field_0 = 34
        header_B_field_0 = 35,
        ....
};

So we have:
proto_hdr_type = proto_hdr_field / 32
bit offset = proto_hdr_field % 32

To simply the protocol header's operations, couple help macros are added.
For example, to select src IP and dst port as input set for an IPv4/UDP
flow.

we have:
struct virtchnl_proto_hdr hdr[2];

VIRTCHNL_SET_PROTO_HDR_TYPE(&hdr[0], IPV4)
VIRTCHNL_ADD_PROTO_HDR_FIELD(&hdr[0], IPV4, SRC)

VIRTCHNL_SET_PROTO_HDR_TYPE(&hdr[1], UDP)
VIRTCHNL_ADD_PROTO_HDR_FIELD(&hdr[1], UDP, DST)

The byte array is used to store the protocol header of a training package.
The byte array must be network order.

The patch added virtual channel support for iAVF FDIR add/validate/delete
filter. iAVF FDIR is Flow Director for Intel Adaptive Virtual Function
which can direct Ethernet packets to the queues of the Network Interface
Card. Add/delete command is adding or deleting one rule for each virtual
channel message, while validate command is just verifying if this rule
is valid without any other operations.

To add or delete one rule, driver needs to config TCAM and Profile,
build training packets which contains the input set value, and send
the training packets through FDIR Tx queue. In addition, driver needs to
manage the software context to avoid adding duplicated rules, deleting
non-existent rule, input set conflicts and other invalid cases.

NOTE:
Supported pattern/actions and their parse functions are not be included in
this patch, they will be added in a separate one.
Signed-off-by: NJeff Guo <jia.guo@intel.com>
Signed-off-by: NYahui Cao <yahui.cao@intel.com>
Signed-off-by: NSimei Su <simei.su@intel.com>
Signed-off-by: NBeilei Xing <beilei.xing@intel.com>
Signed-off-by: NQi Zhang <qi.z.zhang@intel.com>
Tested-by: NChen Bo <BoX.C.Chen@intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>

The syzbot reported a memleak as follows:

BUG: memory leak
unreferenced object 0xffff888101b41d00 (size 120):
  comm "kworker/u4:0", pid 8, jiffies 4294944270 (age 12.780s)
  backtrace:
    [<ffffffff8125dc56>] alloc_pid+0x66/0x560
    [<ffffffff81226405>] copy_process+0x1465/0x25e0
    [<ffffffff81227943>] kernel_clone+0xf3/0x670
    [<ffffffff812281a1>] kernel_thread+0x61/0x80
    [<ffffffff81253464>] call_usermodehelper_exec_work
    [<ffffffff81253464>] call_usermodehelper_exec_work+0xc4/0x120
    [<ffffffff812591c9>] process_one_work+0x2c9/0x600
    [<ffffffff81259ab9>] worker_thread+0x59/0x5d0
    [<ffffffff812611c8>] kthread+0x178/0x1b0
    [<ffffffff8100227f>] ret_from_fork+0x1f/0x30

unreferenced object 0xffff888110ef5c00 (size 232):
  comm "kworker/u4:0", pid 8414, jiffies 4294944270 (age 12.780s)
  backtrace:
    [<ffffffff8154a0cf>] kmem_cache_zalloc
    [<ffffffff8154a0cf>] __alloc_file+0x1f/0xf0
    [<ffffffff8154a809>] alloc_empty_file+0x69/0x120
    [<ffffffff8154a8f3>] alloc_file+0x33/0x1b0
    [<ffffffff8154ab22>] alloc_file_pseudo+0xb2/0x140
    [<ffffffff81559218>] create_pipe_files+0x138/0x2e0
    [<ffffffff8126c793>] umd_setup+0x33/0x220
    [<ffffffff81253574>] call_usermodehelper_exec_async+0xb4/0x1b0
    [<ffffffff8100227f>] ret_from_fork+0x1f/0x30

After the UMD process exits, the pipe_to_umh/pipe_from_umh and
tgid need to be released.

Fixes: d71fa5c9 ("bpf: Add kernel module with user mode driver that populates bpffs.")
Reported-by: syzbot+44908bb56d2bfe56b28e@syzkaller.appspotmail.com
Signed-off-by: NZqiang <qiang.zhang@windriver.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210317030915.2865-1-qiang.zhang@windriver.com

I was working on a syzbot issue, claiming one device could not be
dismantled because its refcount was -1

unregister_netdevice: waiting for sit0 to become free. Usage count = -1

It would be nice if syzbot could trigger a warning at the time
this reference count became negative.

This patch adds CONFIG_PCPU_DEV_REFCNT options which defaults
to per cpu variables (as before this patch) on SMP builds.

v2: free_dev label in alloc_netdev_mqs() is moved to avoid
    a compiler warning (-Wunused-label), as reported
    by kernel test robot <lkp@intel.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 494c704f ("efi: Use 32-bit alignment for efi_guid_t") updated
the type definition of efi_guid_t to ensure that it always appears
sufficiently aligned (the UEFI spec is ambiguous about this, but given
the fact that its EFI_GUID type is defined in terms of a struct carrying
a uint32_t, the natural alignment is definitely >= 32 bits).

However, we missed the EFI_GUID() macro which is used to instantiate
efi_guid_t literals: that macro is still based on the guid_t type,
which does not have a minimum alignment at all. This results in warnings
such as

  In file included from drivers/firmware/efi/mokvar-table.c:35:
  include/linux/efi.h:1093:34: warning: passing 1-byte aligned argument to
      4-byte aligned parameter 2 of 'get_var' may result in an unaligned pointer
      access [-Walign-mismatch]
          status = get_var(L"SecureBoot", &EFI_GLOBAL_VARIABLE_GUID, NULL, &size,
                                          ^
  include/linux/efi.h:1101:24: warning: passing 1-byte aligned argument to
      4-byte aligned parameter 2 of 'get_var' may result in an unaligned pointer
      access [-Walign-mismatch]
          get_var(L"SetupMode", &EFI_GLOBAL_VARIABLE_GUID, NULL, &size, &setupmode);

The distinction only matters on CPUs that do not support misaligned loads
fully, but 32-bit ARM's load-multiple instructions fall into that category,
and these are likely to be emitted by the compiler that built the firmware
for loading word-aligned 128-bit GUIDs from memory

So re-implement the initializer in terms of our own efi_guid_t type, so that
the alignment becomes a property of the literal's type.

Fixes: 494c704f ("efi: Use 32-bit alignment for efi_guid_t")
Reported-by: NNathan Chancellor <nathan@kernel.org>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NNathan Chancellor <nathan@kernel.org>
Tested-by: NNathan Chancellor <nathan@kernel.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/1327Signed-off-by: NArd Biesheuvel <ardb@kernel.org>

Intel mGbE variant implemented in EHL and TGL can be set to select
different clock frequency based on GPO bits in MAC_GPIO_STATUS register.

We introduce a new "void (*ptp_clk_freq_config)(void *priv)" in platform
data so that if a platform is required to configure the frequency of clock
source, in this case Intel mGBE does, the platform-specific configuration
of the PTP clock setting is done when stmmac_ptp_register() is called.
Signed-off-by: NWong, Vee Khee <vee.khee.wong@intel.com>
Signed-off-by: NVoon Weifeng <weifeng.voon@intel.com>
Co-developed-by: NOng Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: NOng Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the xps maps (xps_cpus_map and xps_rxqs_map) to an array in
net_device. That will simplify a lot the code removing the need for lots
of if/else conditionals as the correct map will be available using its
offset in the array.

This should not modify the xps maps behaviour in any way.
Suggested-by: NAlexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: NAntoine Tenart <atenart@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Embed nr_ids (the number of cpu for the xps cpus map, and the number of
rxqs for the xps cpus map) in dev_maps. That will help not accessing out
of bound memory if those values change after dev_maps was allocated.
Suggested-by: NAlexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: NAntoine Tenart <atenart@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>