Newline characters are added in two verifier error messages,
refactored in Commit afbf21dce6 ("bpf: Support readonly/readwrite
buffers in verifier"). This way, they do not mix with
messages afterwards.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200728221801.1090349-1-yhs@fb.com
Entire net/core subsystem is not built without CONFIG_NET. linux/netdevice.h
just assumes that it's always there, so the easiest way to fix this is to
conditionally compile out bpf_xdp_link_attach() use in bpf/syscall.c.
Fixes: aa8d3a716b ("bpf, xdp: Add bpf_link-based XDP attachment API")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200728190527.110830-1-andriin@fb.com
There are a couple of arguments of the boolean flag zero_size_allowed and
the char pointer buf_info when calling to function check_buffer_access that
are swapped by mistake. Fix these by swapping them to correct the argument
ordering.
Fixes: afbf21dce6 ("bpf: Support readonly/readwrite buffers in verifier")
Addresses-Coverity: ("Array compared to 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200727175411.155179-1-colin.king@canonical.com
Add bpf_link-based API (bpf_xdp_link) to attach BPF XDP program through
BPF_LINK_CREATE command.
bpf_xdp_link is mutually exclusive with direct BPF program attachment,
previous BPF program should be detached prior to attempting to create a new
bpf_xdp_link attachment (for a given XDP mode). Once BPF link is attached, it
can't be replaced by other BPF program attachment or link attachment. It will
be detached only when the last BPF link FD is closed.
bpf_xdp_link will be auto-detached when net_device is shutdown, similarly to
how other BPF links behave (cgroup, flow_dissector). At that point bpf_link
will become defunct, but won't be destroyed until last FD is closed.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200722064603.3350758-5-andriin@fb.com
Architectures like s390, powerpc, arm64, riscv have speical definition of
bpf_user_pt_regs_t. So we need to cast the pointer before passing it to
bpf_get_stack(). This is similar to bpf_get_stack_tp().
Fixes: 03d42fd2d83f ("bpf: Separate bpf_get_[stack|stackid] for perf events BPF")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200724200503.3629591-1-songliubraving@fb.com
local_storage.o has its compile guard as CONFIG_BPF_SYSCALL, which
does not imply that CONFIG_CGROUP is on. Including cgroup-internal.h
when CONFIG_CGROUP is off cause a compilation failure.
Fixes: f67cfc233706 ("bpf: Make cgroup storages shared between programs on the same cgroup")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200724211753.902969-1-zhuyifei1999@gmail.com
This change comes in several parts:
One, the restriction that the CGROUP_STORAGE map can only be used
by one program is removed. This results in the removal of the field
'aux' in struct bpf_cgroup_storage_map, and removal of relevant
code associated with the field, and removal of now-noop functions
bpf_free_cgroup_storage and bpf_cgroup_storage_release.
Second, we permit a key of type u64 as the key to the map.
Providing such a key type indicates that the map should ignore
attach type when comparing map keys. However, for simplicity newly
linked storage will still have the attach type at link time in
its key struct. cgroup_storage_check_btf is adapted to accept
u64 as the type of the key.
Third, because the storages are now shared, the storages cannot
be unconditionally freed on program detach. There could be two
ways to solve this issue:
* A. Reference count the usage of the storages, and free when the
last program is detached.
* B. Free only when the storage is impossible to be referred to
again, i.e. when either the cgroup_bpf it is attached to, or
the map itself, is freed.
Option A has the side effect that, when the user detach and
reattach a program, whether the program gets a fresh storage
depends on whether there is another program attached using that
storage. This could trigger races if the user is multi-threaded,
and since nondeterminism in data races is evil, go with option B.
The both the map and the cgroup_bpf now tracks their associated
storages, and the storage unlink and free are removed from
cgroup_bpf_detach and added to cgroup_bpf_release and
cgroup_storage_map_free. The latter also new holds the cgroup_mutex
to prevent any races with the former.
Fourth, on attach, we reuse the old storage if the key already
exists in the map, via cgroup_storage_lookup. If the storage
does not exist yet, we create a new one, and publish it at the
last step in the attach process. This does not create a race
condition because for the whole attach the cgroup_mutex is held.
We keep track of an array of new storages that was allocated
and if the process fails only the new storages would get freed.
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/d5401c6106728a00890401190db40020a1f84ff1.1595565795.git.zhuyifei@google.com
bpf_get_[stack|stackid] on perf_events with precise_ip uses callchain
attached to perf_sample_data. If this callchain is not presented, do not
allow attaching BPF program that calls bpf_get_[stack|stackid] to this
event.
In the error case, -EPROTO is returned so that libbpf can identify this
error and print proper hint message.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723180648.1429892-3-songliubraving@fb.com
Calling get_perf_callchain() on perf_events from PEBS entries may cause
unwinder errors. To fix this issue, the callchain is fetched early. Such
perf_events are marked with __PERF_SAMPLE_CALLCHAIN_EARLY.
Similarly, calling bpf_get_[stack|stackid] on perf_events from PEBS may
also cause unwinder errors. To fix this, add separate version of these
two helpers, bpf_get_[stack|stackid]_pe. These two hepers use callchain in
bpf_perf_event_data_kern->data->callchain.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723180648.1429892-2-songliubraving@fb.com
The bpf iterators for array and percpu array
are implemented. Similar to hash maps, for percpu
array map, bpf program will receive values
from all cpus.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184115.590532-1-yhs@fb.com
The bpf iterators for hash, percpu hash, lru hash
and lru percpu hash are implemented. During link time,
bpf_iter_reg->check_target() will check map type
and ensure the program access key/value region is
within the map defined key/value size limit.
For percpu hash and lru hash maps, the bpf program
will receive values for all cpus. The map element
bpf iterator infrastructure will prepare value
properly before passing the value pointer to the
bpf program.
This patch set supports readonly map keys and
read/write map values. It does not support deleting
map elements, e.g., from hash tables. If there is
a user case for this, the following mechanism can
be used to support map deletion for hashtab, etc.
- permit a new bpf program return value, e.g., 2,
to let bpf iterator know the map element should
be removed.
- since bucket lock is taken, the map element will be
queued.
- once bucket lock is released after all elements under
this bucket are traversed, all to-be-deleted map
elements can be deleted.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184114.590470-1-yhs@fb.com
The bpf iterator for map elements are implemented.
The bpf program will receive four parameters:
bpf_iter_meta *meta: the meta data
bpf_map *map: the bpf_map whose elements are traversed
void *key: the key of one element
void *value: the value of the same element
Here, meta and map pointers are always valid, and
key has register type PTR_TO_RDONLY_BUF_OR_NULL and
value has register type PTR_TO_RDWR_BUF_OR_NULL.
The kernel will track the access range of key and value
during verification time. Later, these values will be compared
against the values in the actual map to ensure all accesses
are within range.
A new field iter_seq_info is added to bpf_map_ops which
is used to add map type specific information, i.e., seq_ops,
init/fini seq_file func and seq_file private data size.
Subsequent patches will have actual implementation
for bpf_map_ops->iter_seq_info.
In user space, BPF_ITER_LINK_MAP_FD needs to be
specified in prog attr->link_create.flags, which indicates
that attr->link_create.target_fd is a map_fd.
The reason for such an explicit flag is for possible
future cases where one bpf iterator may allow more than
one possible customization, e.g., pid and cgroup id for
task_file.
Current kernel internal implementation only allows
the target to register at most one required bpf_iter_link_info.
To support the above case, optional bpf_iter_link_info's
are needed, the target can be extended to register such link
infos, and user provided link_info needs to match one of
target supported ones.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184112.590360-1-yhs@fb.com
Readonly and readwrite buffer register states
are introduced. Totally four states,
PTR_TO_RDONLY_BUF[_OR_NULL] and PTR_TO_RDWR_BUF[_OR_NULL]
are supported. As suggested by their respective
names, PTR_TO_RDONLY_BUF[_OR_NULL] are for
readonly buffers and PTR_TO_RDWR_BUF[_OR_NULL]
for read/write buffers.
These new register states will be used
by later bpf map element iterator.
New register states share some similarity to
PTR_TO_TP_BUFFER as it will calculate accessed buffer
size during verification time. The accessed buffer
size will be later compared to other metrics during
later attach/link_create time.
Similar to reg_state PTR_TO_BTF_ID_OR_NULL in bpf
iterator programs, PTR_TO_RDONLY_BUF_OR_NULL or
PTR_TO_RDWR_BUF_OR_NULL reg_types can be set at
prog->aux->bpf_ctx_arg_aux, and bpf verifier will
retrieve the values during btf_ctx_access().
Later bpf map element iterator implementation
will show how such information will be assigned
during target registeration time.
The verifier is also enhanced such that PTR_TO_RDONLY_BUF
can be passed to ARG_PTR_TO_MEM[_OR_NULL] helper argument, and
PTR_TO_RDWR_BUF can be passed to ARG_PTR_TO_MEM[_OR_NULL] or
ARG_PTR_TO_UNINIT_MEM.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184111.590274-1-yhs@fb.com
This patch refactored target bpf_iter_init_seq_priv_t callback
function to accept additional information. This will be needed
in later patches for map element targets since a particular
map should be passed to traverse elements for that particular
map. In the future, other information may be passed to target
as well, e.g., pid, cgroup id, etc. to customize the iterator.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184110.590156-1-yhs@fb.com
There is no functionality change for this patch.
Struct bpf_iter_reg is used to register a bpf_iter target,
which includes information for both prog_load, link_create
and seq_file creation.
This patch puts fields related seq_file creation into
a different structure. This will be useful for map
elements iterator where one iterator covers different
map types and different map types may have different
seq_ops, init/fini private_data function and
private_data size.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184109.590030-1-yhs@fb.com
It's mostly a copy paste of commit 6086d29def ("bpf: Add bpf_map iterator")
that is use to implement bpf_seq_file opreations to traverse all bpf programs.
v1->v2: Tweak to use build time btf_id
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Currently, the pos pointer in bpf iterator map/task/task_file
seq_ops->start() is always incremented.
This is incorrect. It should be increased only if
*pos is 0 (for SEQ_START_TOKEN) since these start()
function actually returns the first real object.
If *pos is not 0, it merely found the object
based on the state in seq->private, and not really
advancing the *pos. This patch fixed this issue
by only incrementing *pos if it is 0.
Note that the old *pos calculation, although not
correct, does not affect correctness of bpf_iter
as bpf_iter seq_file->read() does not support llseek.
This patch also renamed "mid" in bpf_map iterator
seq_file private data to "map_id" for better clarity.
Fixes: 6086d29def ("bpf: Add bpf_map iterator")
Fixes: eaaacd2391 ("bpf: Add task and task/file iterator targets")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200722195156.4029817-1-yhs@fb.com
The UDP reuseport conflict was a little bit tricky.
The net-next code, via bpf-next, extracted the reuseport handling
into a helper so that the BPF sk lookup code could invoke it.
At the same time, the logic for reuseport handling of unconnected
sockets changed via commit efc6b6f6c3
which changed the logic to carry on the reuseport result into the
rest of the lookup loop if we do not return immediately.
This requires moving the reuseport_has_conns() logic into the callers.
While we are here, get rid of inline directives as they do not belong
in foo.c files.
The other changes were cases of more straightforward overlapping
modifications.
Signed-off-by: David S. Miller <davem@davemloft.net>
If a tracee is uprobed and it hits int3 inserted by debugger, handle_swbp()
does send_sig(SIGTRAP, current, 0) which means si_code == SI_USER. This used
to work when this code was written, but then GDB started to validate si_code
and now it simply can't use breakpoints if the tracee has an active uprobe:
# cat test.c
void unused_func(void)
{
}
int main(void)
{
return 0;
}
# gcc -g test.c -o test
# perf probe -x ./test -a unused_func
# perf record -e probe_test:unused_func gdb ./test -ex run
GNU gdb (GDB) 10.0.50.20200714-git
...
Program received signal SIGTRAP, Trace/breakpoint trap.
0x00007ffff7ddf909 in dl_main () from /lib64/ld-linux-x86-64.so.2
(gdb)
The tracee hits the internal breakpoint inserted by GDB to monitor shared
library events but GDB misinterprets this SIGTRAP and reports a signal.
Change handle_swbp() to use force_sig(SIGTRAP), this matches do_int3_user()
and fixes the problem.
This is the minimal fix for -stable, arch/x86/kernel/uprobes.c is equally
wrong; it should use send_sigtrap(TRAP_TRACE) instead of send_sig(SIGTRAP),
but this doesn't confuse GDB and needs another x86-specific patch.
Reported-by: Aaron Merey <amerey@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200723154420.GA32043@redhat.com
Since the default_wake_function() passes its flags onto
try_to_wake_up(), warn if those flags collide with internal values.
Given that the supplied flags are garbage, no repair can be done but at
least alert the user to the damage they are causing.
In the belief that these errors should be picked up during testing, the
warning is only compiled in under CONFIG_SCHED_DEBUG.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20200723201042.18861-1-chris@chris-wilson.co.uk
There is apparently one site that violates the rule that only current
and ttwu() will modify task->state, namely ptrace_{,un}freeze_traced()
will change task->state for a remote task.
Oleg explains:
"TASK_TRACED/TASK_STOPPED was always protected by siglock. In
particular, ttwu(__TASK_TRACED) must be always called with siglock
held. That is why ptrace_freeze_traced() assumes it can safely do
s/TASK_TRACED/__TASK_TRACED/ under spin_lock(siglock)."
This breaks the ordering scheme introduced by commit:
dbfb089d36 ("sched: Fix loadavg accounting race")
Specifically, the reload not matching no longer implies we don't have
to block.
Simply things by noting that what we need is a LOAD->STORE ordering
and this can be provided by a control dependency.
So replace:
prev_state = prev->state;
raw_spin_lock(&rq->lock);
smp_mb__after_spinlock(); /* SMP-MB */
if (... && prev_state && prev_state == prev->state)
deactivate_task();
with:
prev_state = prev->state;
if (... && prev_state) /* CTRL-DEP */
deactivate_task();
Since that already implies the 'prev->state' load must be complete
before allowing the 'prev->on_rq = 0' store to become visible.
Fixes: dbfb089d36 ("sched: Fix loadavg accounting race")
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Tested-by: Christian Brauner <christian.brauner@ubuntu.com>
One additional field btf_id is added to struct
bpf_ctx_arg_aux to store the precomputed btf_ids.
The btf_id is computed at build time with
BTF_ID_LIST or BTF_ID_LIST_GLOBAL macro definitions.
All existing bpf iterators are changed to used
pre-compute btf_ids.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720163403.1393551-1-yhs@fb.com
Currently, socket types (struct tcp_sock, udp_sock, etc.)
used by bpf_skc_to_*() helpers are computed when vmlinux_btf
is first built in the kernel.
Commit 5a2798ab32
("bpf: Add BTF_ID_LIST/BTF_ID/BTF_ID_UNUSED macros")
implemented a mechanism to compute btf_ids at kernel build
time which can simplify kernel implementation and reduce
runtime overhead by removing in-kernel btf_id calculation.
This patch did exactly this, removing in-kernel btf_id
computation and utilizing build-time btf_id computation.
If CONFIG_DEBUG_INFO_BTF is not defined, BTF_ID_LIST will
define an array with size of 5, which is not enough for
btf_sock_ids. So define its own static array if
CONFIG_DEBUG_INFO_BTF is not defined.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720163358.1393023-1-yhs@fb.com
When CONFIG_NET is set but CONFIG_INET isn't, build fails with:
ld: kernel/bpf/net_namespace.o: in function `netns_bpf_attach_type_unneed':
kernel/bpf/net_namespace.c:32: undefined reference to `bpf_sk_lookup_enabled'
ld: kernel/bpf/net_namespace.o: in function `netns_bpf_attach_type_need':
kernel/bpf/net_namespace.c:43: undefined reference to `bpf_sk_lookup_enabled'
This is because without CONFIG_INET bpf_sk_lookup_enabled symbol is not
available. Wrap references to bpf_sk_lookup_enabled with preprocessor
conditionals.
Fixes: 1559b4aa1d ("inet: Run SK_LOOKUP BPF program on socket lookup")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/bpf/20200721100716.720477-1-jakub@cloudflare.com
- A timer which is already expired at enqueue time can set the
base->next_expiry value backwards. As a consequence base->clk can be set
back as well. This can lead to timers expiring early. Add a sanity check
to prevent this.
- When a timer is queued with an expiry time beyond the wheel capacity
then it should be queued in the bucket of the last wheel level which is
expiring last. The code adjusts expiry time to the maximum wheel
capacity, which is only correct when the wheel clock is 0. Aside of that
the check whether the delta is larger than wheel capacity does not check
the delta, it checks the expiry value itself. As a result timers can
expire at random.
Fix this by checking the right variable and adjust expiry time so it
becomes base->clock plus capacity which places it into the outmost
bucket in the last wheel level.
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Merge tag 'timers-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull timer fixes from Thomas Gleixner:
"Two fixes for the timer wheel:
- A timer which is already expired at enqueue time can set the
base->next_expiry value backwards. As a consequence base->clk can
be set back as well. This can lead to timers expiring early. Add a
sanity check to prevent this.
- When a timer is queued with an expiry time beyond the wheel
capacity then it should be queued in the bucket of the last wheel
level which is expiring last.
The code adjusted the expiry time to the maximum wheel capacity,
which is only correct when the wheel clock is 0. Aside of that the
check whether the delta is larger than wheel capacity does not
check the delta, it checks the expiry value itself. As a result
timers can expire at random.
Fix this by checking the right variable and adjust expiry time so
it becomes base->clock plus capacity which places it into the
outmost bucket in the last wheel level"
* tag 'timers-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timer: Fix wheel index calculation on last level
timer: Prevent base->clk from moving backward
- Plug a load average accounting race which was introduced with a recent
optimization casing load average to show bogus numbers.
- Fix the rseq CPU id initialization for new tasks. sched_fork() does not
update the rseq CPU id so the id is the stale id of the parent task,
which can cause user space data corruption.
- Handle a 0 return value of task_h_load() correctly in the load balancer,
which does not decrease imbalance and therefore pulls until the maximum
number of loops is reached, which might be all tasks just created by a
fork bomb.
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Merge tag 'sched-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull scheduler fixes from Thomas Gleixner:
"A set of scheduler fixes:
- Plug a load average accounting race which was introduced with a
recent optimization casing load average to show bogus numbers.
- Fix the rseq CPU id initialization for new tasks. sched_fork() does
not update the rseq CPU id so the id is the stale id of the parent
task, which can cause user space data corruption.
- Handle a 0 return value of task_h_load() correctly in the load
balancer, which does not decrease imbalance and therefore pulls
until the maximum number of loops is reached, which might be all
tasks just created by a fork bomb"
* tag 'sched-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: handle case of task_h_load() returning 0
sched: Fix unreliable rseq cpu_id for new tasks
sched: Fix loadavg accounting race
- Make the handling of the firmware node consistent and do not free the
node after the domain has been created successfully. The core code
stores a pointer to it which can lead to a use after free or double
free.
This used to "work" because the pointer was not stored when the initial
code was written, but at some point later it was required to store
it. Of course nobody noticed that the existing users break that way.
- Handle affinity setting on inactive interrupts correctly when
hierarchical irq domains are enabled. When interrupts are inactive with
the modern hierarchical irqdomain design, the interrupt chips are not
necessarily in a state where affinity changes can be handled. The legacy
irq chip design allowed this because interrupts are immediately fully
initialized at allocation time. X86 has a hacky workaround for this, but
other implementations do not. This cased malfunction on GIC-V3. Instead
of playing whack a mole to find all affected drivers, change the core
code to store the requested affinity setting and then establish it when
the interrupt is allocated, which makes the X86 hack go away.
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Merge tag 'irq-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull irq fixes from Thomas Gleixner:
"Two fixes for the interrupt subsystem:
- Make the handling of the firmware node consistent and do not free
the node after the domain has been created successfully. The core
code stores a pointer to it which can lead to a use after free or
double free.
This used to "work" because the pointer was not stored when the
initial code was written, but at some point later it was required
to store it. Of course nobody noticed that the existing users break
that way.
- Handle affinity setting on inactive interrupts correctly when
hierarchical irq domains are enabled.
When interrupts are inactive with the modern hierarchical irqdomain
design, the interrupt chips are not necessarily in a state where
affinity changes can be handled. The legacy irq chip design allowed
this because interrupts are immediately fully initialized at
allocation time. X86 has a hacky workaround for this, but other
implementations do not.
This cased malfunction on GIC-V3. Instead of playing whack a mole
to find all affected drivers, change the core code to store the
requested affinity setting and then establish it when the interrupt
is allocated, which makes the X86 hack go away"
* tag 'irq-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/affinity: Handle affinity setting on inactive interrupts correctly
irqdomain/treewide: Keep firmware node unconditionally allocated
Run a BPF program before looking up a listening socket on the receive path.
Program selects a listening socket to yield as result of socket lookup by
calling bpf_sk_assign() helper and returning SK_PASS code. Program can
revert its decision by assigning a NULL socket with bpf_sk_assign().
Alternatively, BPF program can also fail the lookup by returning with
SK_DROP, or let the lookup continue as usual with SK_PASS on return, when
no socket has been selected with bpf_sk_assign().
This lets the user match packets with listening sockets freely at the last
possible point on the receive path, where we know that packets are destined
for local delivery after undergoing policing, filtering, and routing.
With BPF code selecting the socket, directing packets destined to an IP
range or to a port range to a single socket becomes possible.
In case multiple programs are attached, they are run in series in the order
in which they were attached. The end result is determined from return codes
of all the programs according to following rules:
1. If any program returned SK_PASS and selected a valid socket, the socket
is used as result of socket lookup.
2. If more than one program returned SK_PASS and selected a socket,
last selection takes effect.
3. If any program returned SK_DROP, and no program returned SK_PASS and
selected a socket, socket lookup fails with -ECONNREFUSED.
4. If all programs returned SK_PASS and none of them selected a socket,
socket lookup continues to htable-based lookup.
Suggested-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200717103536.397595-5-jakub@cloudflare.com
Add a new program type BPF_PROG_TYPE_SK_LOOKUP with a dedicated attach type
BPF_SK_LOOKUP. The new program kind is to be invoked by the transport layer
when looking up a listening socket for a new connection request for
connection oriented protocols, or when looking up an unconnected socket for
a packet for connection-less protocols.
When called, SK_LOOKUP BPF program can select a socket that will receive
the packet. This serves as a mechanism to overcome the limits of what
bind() API allows to express. Two use-cases driving this work are:
(1) steer packets destined to an IP range, on fixed port to a socket
192.0.2.0/24, port 80 -> NGINX socket
(2) steer packets destined to an IP address, on any port to a socket
198.51.100.1, any port -> L7 proxy socket
In its run-time context program receives information about the packet that
triggered the socket lookup. Namely IP version, L4 protocol identifier, and
address 4-tuple. Context can be further extended to include ingress
interface identifier.
To select a socket BPF program fetches it from a map holding socket
references, like SOCKMAP or SOCKHASH, and calls bpf_sk_assign(ctx, sk, ...)
helper to record the selection. Transport layer then uses the selected
socket as a result of socket lookup.
In its basic form, SK_LOOKUP acts as a filter and hence must return either
SK_PASS or SK_DROP. If the program returns with SK_PASS, transport should
look for a socket to receive the packet, or use the one selected by the
program if available, while SK_DROP informs the transport layer that the
lookup should fail.
This patch only enables the user to attach an SK_LOOKUP program to a
network namespace. Subsequent patches hook it up to run on local delivery
path in ipv4 and ipv6 stacks.
Suggested-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200717103536.397595-3-jakub@cloudflare.com
Extend the BPF netns link callbacks to rebuild (grow/shrink) or update the
prog_array at given position when link gets attached/updated/released.
This let's us lift the limit of having just one link attached for the new
attach type introduced by subsequent patch.
No functional changes intended.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200717103536.397595-2-jakub@cloudflare.com
Setting interrupt affinity on inactive interrupts is inconsistent when
hierarchical irq domains are enabled. The core code should just store the
affinity and not call into the irq chip driver for inactive interrupts
because the chip drivers may not be in a state to handle such requests.
X86 has a hacky workaround for that but all other irq chips have not which
causes problems e.g. on GIC V3 ITS.
Instead of adding more ugly hacks all over the place, solve the problem in
the core code. If the affinity is set on an inactive interrupt then:
- Store it in the irq descriptors affinity mask
- Update the effective affinity to reflect that so user space has
a consistent view
- Don't call into the irq chip driver
This is the core equivalent of the X86 workaround and works correctly
because the affinity setting is established in the irq chip when the
interrupt is activated later on.
Note, that this is only effective when hierarchical irq domains are enabled
by the architecture. Doing it unconditionally would break legacy irq chip
implementations.
For hierarchial irq domains this works correctly as none of the drivers can
have a dependency on affinity setting in inactive state by design.
Remove the X86 workaround as it is not longer required.
Fixes: 02edee152d ("x86/apic/vector: Ignore set_affinity call for inactive interrupts")
Reported-by: Ali Saidi <alisaidi@amazon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Ali Saidi <alisaidi@amazon.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200529015501.15771-1-alisaidi@amazon.com
Link: https://lkml.kernel.org/r/877dv2rv25.fsf@nanos.tec.linutronix.de
When an expiration delta falls into the last level of the wheel, that delta
has be compared against the maximum possible delay and reduced to fit in if
necessary.
However instead of comparing the delta against the maximum, the code
compares the actual expiry against the maximum. Then instead of fixing the
delta to fit in, it sets the maximum delta as the expiry value.
This can result in various undesired outcomes, the worst possible one
being a timer expiring 15 days ahead to fire immediately.
Fixes: 500462a9de ("timers: Switch to a non-cascading wheel")
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200717140551.29076-2-frederic@kernel.org
task_h_load() can return 0 in some situations like running stress-ng
mmapfork, which forks thousands of threads, in a sched group on a 224 cores
system. The load balance doesn't handle this correctly because
env->imbalance never decreases and it will stop pulling tasks only after
reaching loop_max, which can be equal to the number of running tasks of
the cfs. Make sure that imbalance will be decreased by at least 1.
misfit task is the other feature that doesn't handle correctly such
situation although it's probably more difficult to face the problem
because of the smaller number of CPUs and running tasks on heterogenous
system.
We can't simply ensure that task_h_load() returns at least one because it
would imply to handle underflow in other places.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: <stable@vger.kernel.org> # v4.4+
Link: https://lkml.kernel.org/r/20200710152426.16981-1-vincent.guittot@linaro.org
Introduce XDP_REDIRECT support for eBPF programs attached to cpumap
entries.
This patch has been tested on Marvell ESPRESSObin using a modified
version of xdp_redirect_cpu sample in order to attach a XDP program
to CPUMAP entries to perform a redirect on the mvneta interface.
In particular the following scenario has been tested:
rq (cpu0) --> mvneta - XDP_REDIRECT (cpu0) --> CPUMAP - XDP_REDIRECT (cpu1) --> mvneta
$./xdp_redirect_cpu -p xdp_cpu_map0 -d eth0 -c 1 -e xdp_redirect \
-f xdp_redirect_kern.o -m tx_port -r eth0
tx: 285.2 Kpps rx: 285.2 Kpps
Attaching a simple XDP program on eth0 to perform XDP_TX gives
comparable results:
tx: 288.4 Kpps rx: 288.4 Kpps
Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/2cf8373a731867af302b00c4ff16c122630c4980.1594734381.git.lorenzo@kernel.org
Introduce the capability to attach an eBPF program to cpumap entries.
The idea behind this feature is to add the possibility to define on
which CPU run the eBPF program if the underlying hw does not support
RSS. Current supported verdicts are XDP_DROP and XDP_PASS.
This patch has been tested on Marvell ESPRESSObin using xdp_redirect_cpu
sample available in the kernel tree to identify possible performance
regressions. Results show there are no observable differences in
packet-per-second:
$./xdp_redirect_cpu --progname xdp_cpu_map0 --dev eth0 --cpu 1
rx: 354.8 Kpps
rx: 356.0 Kpps
rx: 356.8 Kpps
rx: 356.3 Kpps
rx: 356.6 Kpps
rx: 356.6 Kpps
rx: 356.7 Kpps
rx: 355.8 Kpps
rx: 356.8 Kpps
rx: 356.8 Kpps
Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/5c9febdf903d810b3415732e5cd98491d7d9067a.1594734381.git.lorenzo@kernel.org
As it has been already done for devmap, introduce 'struct bpf_cpumap_val'
to formalize the expected values that can be passed in for a CPUMAP.
Update cpumap code to use the struct.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/754f950674665dae6139c061d28c1d982aaf4170.1594734381.git.lorenzo@kernel.org
Commit 77361825bb ("bpf: cpumap use ptr_ring_consume_batched") changed
away from using single frame ptr_ring dequeue (__ptr_ring_consume) to
consume a batched, but it uses a locked version, which as the comment
explain isn't needed.
Change to use the non-locked version __ptr_ring_consume_batched.
Fixes: 77361825bb ("bpf: cpumap use ptr_ring_consume_batched")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/a9c7d06f9a009e282209f0c8c7b2c5d9b9ad60b9.1594734381.git.lorenzo@kernel.org
There is no guarantee to CMA's placement, so allocating a zone specific
atomic pool from CMA might return memory from a completely different
memory zone. So stop using it.
Fixes: c84dc6e68a ("dma-pool: add additional coherent pools to map to gfp mask")
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
When allocating DMA memory from a pool, the core can only guess which
atomic pool will fit a device's constraints. If it doesn't, get a safer
atomic pool and try again.
Fixes: c84dc6e68a ("dma-pool: add additional coherent pools to map to gfp mask")
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
dma-pool's dev_to_pool() creates the false impression that there is a
way to grantee a mapping between a device's DMA constraints and an
atomic pool. It tuns out it's just a guess, and the device might need to
use an atomic pool containing memory from a 'safer' (or lower) memory
zone.
To help mitigate this, introduce dma_guess_pool() which can be fed a
device's DMA constraints and atomic pools already known to be faulty, in
order for it to provide an better guess on which pool to use.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The function is only used once and can be simplified to a one-liner.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
dma_coherent_ok() checks if a physical memory area fits a device's DMA
constraints.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-07-13
The following pull-request contains BPF updates for your *net-next* tree.
We've added 36 non-merge commits during the last 7 day(s) which contain
a total of 62 files changed, 2242 insertions(+), 468 deletions(-).
The main changes are:
1) Avoid trace_printk warning banner by switching bpf_trace_printk to use
its own tracing event, from Alan.
2) Better libbpf support on older kernels, from Andrii.
3) Additional AF_XDP stats, from Ciara.
4) build time resolution of BTF IDs, from Jiri.
5) BPF_CGROUP_INET_SOCK_RELEASE hook, from Stanislav.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The bpf helper bpf_trace_printk() uses trace_printk() under the hood.
This leads to an alarming warning message originating from trace
buffer allocation which occurs the first time a program using
bpf_trace_printk() is loaded.
We can instead create a trace event for bpf_trace_printk() and enable
it in-kernel when/if we encounter a program using the
bpf_trace_printk() helper. With this approach, trace_printk()
is not used directly and no warning message appears.
This work was started by Steven (see Link) and finished by Alan; added
Steven's Signed-off-by with his permission.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/r/20200628194334.6238b933@oasis.local.home
Link: https://lore.kernel.org/bpf/1594641154-18897-2-git-send-email-alan.maguire@oracle.com
This way the ID is resolved during compile time,
and we can remove the runtime name search.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-7-jolsa@kernel.org
Now when we moved the helpers btf_id arrays into .BTF_ids section,
we can remove the code that resolve those IDs in runtime.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-6-jolsa@kernel.org
Using BTF_ID_LIST macro to define lists for several helpers
using BTF arguments.
And running resolve_btfids on vmlinux elf object during linking,
so the .BTF_ids section gets the IDs resolved.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-5-jolsa@kernel.org
