Since the function __lockdep_init_map() only has one caller, inline it
into its caller. This patch does not change any functionality.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20181207011148.251812-10-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch avoids that sparse complains about a missing declaration for
the lock_classes array when building with CONFIG_DEBUG_LOCKDEP=n.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: johannes.berg@intel.com
Cc: tj@kernel.org
Link: https://lkml.kernel.org/r/20181207011148.251812-9-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The SPDX tags are not present in cpufreq.c and cpufreq_schedutil.c.
Add them and remove the license descriptions
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-12-11
The following pull-request contains BPF updates for your *net-next* tree.
It has three minor merge conflicts, resolutions:
1) tools/testing/selftests/bpf/test_verifier.c
Take first chunk with alignment_prevented_execution.
2) net/core/filter.c
[...]
case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
case bpf_ctx_range(struct __sk_buff, wire_len):
return false;
[...]
3) include/uapi/linux/bpf.h
Take the second chunk for the two cases each.
The main changes are:
1) Add support for BPF line info via BTF and extend libbpf as well
as bpftool's program dump to annotate output with BPF C code to
facilitate debugging and introspection, from Martin.
2) Add support for BPF_ALU | BPF_ARSH | BPF_{K,X} in interpreter
and all JIT backends, from Jiong.
3) Improve BPF test coverage on archs with no efficient unaligned
access by adding an "any alignment" flag to the BPF program load
to forcefully disable verifier alignment checks, from David.
4) Add a new bpf_prog_test_run_xattr() API to libbpf which allows for
proper use of BPF_PROG_TEST_RUN with data_out, from Lorenz.
5) Extend tc BPF programs to use a new __sk_buff field called wire_len
for more accurate accounting of packets going to wire, from Petar.
6) Improve bpftool to allow dumping the trace pipe from it and add
several improvements in bash completion and map/prog dump,
from Quentin.
7) Optimize arm64 BPF JIT to always emit movn/movk/movk sequence for
kernel addresses and add a dedicated BPF JIT backend allocator,
from Ard.
8) Add a BPF helper function for IR remotes to report mouse movements,
from Sean.
9) Various cleanups in BPF prog dump e.g. to make UAPI bpf_prog_info
member naming consistent with existing conventions, from Yonghong
and Song.
10) Misc cleanups and improvements in allowing to pass interface name
via cmdline for xdp1 BPF example, from Matteo.
11) Fix a potential segfault in BPF sample loader's kprobes handling,
from Daniel T.
12) Fix SPDX license in libbpf's README.rst, from Andrey.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
In uapi bpf.h, currently we have the following fields in
the struct bpf_prog_info:
__u32 func_info_cnt;
__u32 line_info_cnt;
__u32 jited_line_info_cnt;
The above field names "func_info_cnt" and "line_info_cnt"
also appear in union bpf_attr for program loading.
The original intention is to keep the names the same
between bpf_prog_info and bpf_attr
so it will imply what we returned to user space will be
the same as what the user space passed to the kernel.
Such a naming convention in bpf_prog_info is not consistent
with other fields like:
__u32 nr_jited_ksyms;
__u32 nr_jited_func_lens;
This patch made this adjustment so in bpf_prog_info
newly introduced *_info_cnt becomes nr_*_info.
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
info.nr_jited_ksyms and info.nr_jited_func_lens cannot be 0 in these two
statements, so we don't need to check them.
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Currently, the destination register is marked as unknown for 32-bit
sub-register move (BPF_MOV | BPF_ALU) whenever the source register type is
SCALAR_VALUE.
This is too conservative that some valid cases will be rejected.
Especially, this may turn a constant scalar value into unknown value that
could break some assumptions of verifier.
For example, test_l4lb_noinline.c has the following C code:
struct real_definition *dst
1: if (!get_packet_dst(&dst, &pckt, vip_info, is_ipv6))
2: return TC_ACT_SHOT;
3:
4: if (dst->flags & F_IPV6) {
get_packet_dst is responsible for initializing "dst" into valid pointer and
return true (1), otherwise return false (0). The compiled instruction
sequence using alu32 will be:
412: (54) (u32) r7 &= (u32) 1
413: (bc) (u32) r0 = (u32) r7
414: (95) exit
insn 413, a BPF_MOV | BPF_ALU, however will turn r0 into unknown value even
r7 contains SCALAR_VALUE 1.
This causes trouble when verifier is walking the code path that hasn't
initialized "dst" inside get_packet_dst, for which case 0 is returned and
we would then expect verifier concluding line 1 in the above C code pass
the "if" check, therefore would skip fall through path starting at line 4.
Now, because r0 returned from callee has became unknown value, so verifier
won't skip analyzing path starting at line 4 and "dst->flags" requires
dereferencing the pointer "dst" which actually hasn't be initialized for
this path.
This patch relaxed the code marking sub-register move destination. For a
SCALAR_VALUE, it is safe to just copy the value from source then truncate
it into 32-bit.
A unit test also included to demonstrate this issue. This test will fail
before this patch.
This relaxation could let verifier skipping more paths for conditional
comparison against immediate. It also let verifier recording a more
accurate/strict value for one register at one state, if this state end up
with going through exit without rejection and it is used for state
comparison later, then it is possible an inaccurate/permissive value is
better. So the real impact on verifier processed insn number is complex.
But in all, without this fix, valid program could be rejected.
>From real benchmarking on kernel selftests and Cilium bpf tests, there is
no impact on processed instruction number when tests ares compiled with
default compilation options. There is slightly improvements when they are
compiled with -mattr=+alu32 after this patch.
Also, test_xdp_noinline/-mattr=+alu32 now passed verification. It is
rejected before this fix.
Insn processed before/after this patch:
default -mattr=+alu32
Kernel selftest
===
test_xdp.o 371/371 369/369
test_l4lb.o 6345/6345 5623/5623
test_xdp_noinline.o 2971/2971 rejected/2727
test_tcp_estates.o 429/429 430/430
Cilium bpf
===
bpf_lb-DLB_L3.o: 2085/2085 1685/1687
bpf_lb-DLB_L4.o: 2287/2287 1986/1982
bpf_lb-DUNKNOWN.o: 690/690 622/622
bpf_lxc.o: 95033/95033 N/A
bpf_netdev.o: 7245/7245 N/A
bpf_overlay.o: 2898/2898 3085/2947
NOTE:
- bpf_lxc.o and bpf_netdev.o compiled by -mattr=+alu32 are rejected by
verifier due to another issue inside verifier on supporting alu32
binary.
- Each cilium bpf program could generate several processed insn number,
above number is sum of them.
v1->v2:
- Restrict the change on SCALAR_VALUE.
- Update benchmark numbers on Cilium bpf tests.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Since printk_time can be toggled via /sys/module/printk/parameters/time ,
it is not safe to assume that output length does not change across
multiple msg_print_text() calls. If we hit this race, we can observe
failures such as SYSLOG_ACTION_READ_ALL writes more bytes than userspace
has supplied, SYSLOG_ACTION_SIZE_UNREAD returns -EFAULT when succeeded,
SYSLOG_ACTION_READ reads garbage memory or even triggers an kernel oops
at _copy_to_user() due to integer overflow.
To close this race, get a snapshot value of printk_time and pass it to
SYSLOG_ACTION_READ, SYSLOG_ACTION_READ_ALL, SYSLOG_ACTION_SIZE_UNREAD and
kmsg_dump_get_buffer().
Link: http://lkml.kernel.org/r/555af37c-b9e0-f940-cb73-a78eba2d4944@i-love.sakura.ne.jp
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Several conflicts, seemingly all over the place.
I used Stephen Rothwell's sample resolutions for many of these, if not
just to double check my own work, so definitely the credit largely
goes to him.
The NFP conflict consisted of a bug fix (moving operations
past the rhashtable operation) while chaning the initial
argument in the function call in the moved code.
The net/dsa/master.c conflict had to do with a bug fix intermixing of
making dsa_master_set_mtu() static with the fixing of the tagging
attribute location.
cls_flower had a conflict because the dup reject fix from Or
overlapped with the addition of port range classifiction.
__set_phy_supported()'s conflict was relatively easy to resolve
because Andrew fixed it in both trees, so it was just a matter
of taking the net-next copy. Or at least I think it was :-)
Joe Stringer's fix to the handling of netns id 0 in bpf_sk_lookup()
intermixed with changes on how the sdif and caller_net are calculated
in these code paths in net-next.
The remaining BPF conflicts were largely about the addition of the
__bpf_md_ptr stuff in 'net' overlapping with adjustments and additions
to the relevant data structure where the MD pointer macros are used.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
"A decent batch of fixes here. I'd say about half are for problems that
have existed for a while, and half are for new regressions added in
the 4.20 merge window.
1) Fix 10G SFP phy module detection in mvpp2, from Baruch Siach.
2) Revert bogus emac driver change, from Benjamin Herrenschmidt.
3) Handle BPF exported data structure with pointers when building
32-bit userland, from Daniel Borkmann.
4) Memory leak fix in act_police, from Davide Caratti.
5) Check RX checksum offload in RX descriptors properly in aquantia
driver, from Dmitry Bogdanov.
6) SKB unlink fix in various spots, from Edward Cree.
7) ndo_dflt_fdb_dump() only works with ethernet, enforce this, from
Eric Dumazet.
8) Fix FID leak in mlxsw driver, from Ido Schimmel.
9) IOTLB locking fix in vhost, from Jean-Philippe Brucker.
10) Fix SKB truesize accounting in ipv4/ipv6/netfilter frag memory
limits otherwise namespace exit can hang. From Jiri Wiesner.
11) Address block parsing length fixes in x25 from Martin Schiller.
12) IRQ and ring accounting fixes in bnxt_en, from Michael Chan.
13) For tun interfaces, only iface delete works with rtnl ops, enforce
this by disallowing add. From Nicolas Dichtel.
14) Use after free in liquidio, from Pan Bian.
15) Fix SKB use after passing to netif_receive_skb(), from Prashant
Bhole.
16) Static key accounting and other fixes in XPS from Sabrina Dubroca.
17) Partially initialized flow key passed to ip6_route_output(), from
Shmulik Ladkani.
18) Fix RTNL deadlock during reset in ibmvnic driver, from Thomas
Falcon.
19) Several small TCP fixes (off-by-one on window probe abort, NULL
deref in tail loss probe, SNMP mis-estimations) from Yuchung
Cheng"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (93 commits)
net/sched: cls_flower: Reject duplicated rules also under skip_sw
bnxt_en: Fix _bnxt_get_max_rings() for 57500 chips.
bnxt_en: Fix NQ/CP rings accounting on the new 57500 chips.
bnxt_en: Keep track of reserved IRQs.
bnxt_en: Fix CNP CoS queue regression.
net/mlx4_core: Correctly set PFC param if global pause is turned off.
Revert "net/ibm/emac: wrong bit is used for STA control"
neighbour: Avoid writing before skb->head in neigh_hh_output()
ipv6: Check available headroom in ip6_xmit() even without options
tcp: lack of available data can also cause TSO defer
ipv6: sr: properly initialize flowi6 prior passing to ip6_route_output
mlxsw: spectrum_switchdev: Fix VLAN device deletion via ioctl
mlxsw: spectrum_router: Relax GRE decap matching check
mlxsw: spectrum_switchdev: Avoid leaking FID's reference count
mlxsw: spectrum_nve: Remove easily triggerable warnings
ipv4: ipv6: netfilter: Adjust the frag mem limit when truesize changes
sctp: frag_point sanity check
tcp: fix NULL ref in tail loss probe
tcp: Do not underestimate rwnd_limited
net: use skb_list_del_init() to remove from RX sublists
...
This patch adds bpf_line_info support.
It accepts an array of bpf_line_info objects during BPF_PROG_LOAD.
The "line_info", "line_info_cnt" and "line_info_rec_size" are added
to the "union bpf_attr". The "line_info_rec_size" makes
bpf_line_info extensible in the future.
The new "check_btf_line()" ensures the userspace line_info is valid
for the kernel to use.
When the verifier is translating/patching the bpf_prog (through
"bpf_patch_insn_single()"), the line_infos' insn_off is also
adjusted by the newly added "bpf_adj_linfo()".
If the bpf_prog is jited, this patch also provides the jited addrs (in
aux->jited_linfo) for the corresponding line_info.insn_off.
"bpf_prog_fill_jited_linfo()" is added to fill the aux->jited_linfo.
It is currently called by the x86 jit. Other jits can also use
"bpf_prog_fill_jited_linfo()" and it will be done in the followup patches.
In the future, if it deemed necessary, a particular jit could also provide
its own "bpf_prog_fill_jited_linfo()" implementation.
A few "*line_info*" fields are added to the bpf_prog_info such
that the user can get the xlated line_info back (i.e. the line_info
with its insn_off reflecting the translated prog). The jited_line_info
is available if the prog is jited. It is an array of __u64.
If the prog is not jited, jited_line_info_cnt is 0.
The verifier's verbose log with line_info will be done in
a follow up patch.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch remove the rejection on BPF_ALU | BPF_ARSH as we have supported
them on interpreter and all JIT back-ends
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch implements interpreting BPF_ALU | BPF_ARSH. Do arithmetic right
shift on low 32-bit sub-register, and zero the high 32 bits.
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
due to a missing mutex protection.
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Merge tag 'trace-v4.20-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"This is a single commit that fixes a bug in uprobes SDT code due to a
missing mutex protection"
* tag 'trace-v4.20-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
Uprobes: Fix kernel oops with delayed_uprobe_remove()
In kdump case, there exists only one dedicated memblock region as usable
memory (crashk_res). With this patch, kexec_walk_memblock() runs a given
callback function on this region.
Cosmetic change: 0 to MEMBLOCK_NONE at for_each_free_mem_range*()
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Memblock list is another source for usable system memory layout.
So move powerpc's arch_kexec_walk_mem() to common code so that other
memblock-based architectures, particularly arm64, can also utilise it.
A moved function is now renamed to kexec_walk_memblock() and integrated
into kexec_locate_mem_hole(), which will now be usable for all
architectures with no need for overriding arch_kexec_walk_mem().
With this change, arch_kexec_walk_mem() need no longer be a weak function,
and was now renamed to kexec_walk_resources().
Since powerpc doesn't support kdump in its kexec_file_load(), the current
kexec_walk_memblock() won't work for kdump either in this form, this will
be fixed in the next patch.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Acked-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Since s390 already knows where to locate buffers, calling
arch_kexec_mem_walk() has no sense. So we can just drop it as kbuf->mem
indicates this while all other architectures sets it to 0 initially.
This change is a preparatory work for the next patch, where all the
variant memory walks, either on system resource or memblock, will be
put in one common place so that it will satisfy all the architectures'
need.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Change this function from static to global so that arm64 can implement
its own arch_kimage_file_post_load_cleanup() later using
kexec_image_post_load_cleanup_default().
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
There could be a race between task exit and probe unregister:
exit_mm()
mmput()
__mmput() uprobe_unregister()
uprobe_clear_state() put_uprobe()
delayed_uprobe_remove() delayed_uprobe_remove()
put_uprobe() is calling delayed_uprobe_remove() without taking
delayed_uprobe_lock and thus the race sometimes results in a
kernel crash. Fix this by taking delayed_uprobe_lock before
calling delayed_uprobe_remove() from put_uprobe().
Detailed crash log can be found at:
Link: http://lkml.kernel.org/r/000000000000140c370577db5ece@google.com
Link: http://lkml.kernel.org/r/20181205033423.26242-1-ravi.bangoria@linux.ibm.com
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reported-by: syzbot+cb1fb754b771caca0a88@syzkaller.appspotmail.com
Fixes: 1cc33161a8 ("uprobes: Support SDT markers having reference count (semaphore)")
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Function graph tracing recurses into itself when stackleak is enabled,
causing the ftrace graph selftest to run for up to 90 seconds and
trigger the softlockup watchdog.
Breakpoint 2, ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:200
200 mcount_get_lr_addr x0 // pointer to function's saved lr
(gdb) bt
\#0 ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:200
\#1 0xffffff80081d5280 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:153
\#2 0xffffff8008555484 in stackleak_track_stack () at ../kernel/stackleak.c:106
\#3 0xffffff8008421ff8 in ftrace_ops_test (ops=0xffffff8009eaa840 <graph_ops>, ip=18446743524091297036, regs=<optimized out>) at ../kernel/trace/ftrace.c:1507
\#4 0xffffff8008428770 in __ftrace_ops_list_func (regs=<optimized out>, ignored=<optimized out>, parent_ip=<optimized out>, ip=<optimized out>) at ../kernel/trace/ftrace.c:6286
\#5 ftrace_ops_no_ops (ip=18446743524091297036, parent_ip=18446743524091242824) at ../kernel/trace/ftrace.c:6321
\#6 0xffffff80081d5280 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:153
\#7 0xffffff800832fd10 in irq_find_mapping (domain=0xffffffc03fc4bc80, hwirq=27) at ../kernel/irq/irqdomain.c:876
\#8 0xffffff800832294c in __handle_domain_irq (domain=0xffffffc03fc4bc80, hwirq=27, lookup=true, regs=0xffffff800814b840) at ../kernel/irq/irqdesc.c:650
\#9 0xffffff80081d52b4 in ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:205
Rework so we mark stackleak_track_stack as notrace
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
The later patch will introduce "struct bpf_line_info" which
has member "line_off" and "file_off" referring back to the
string section in btf. The line_"off" and file_"off"
are more consistent to the naming convention in btf.h that
means "offset" (e.g. name_off in "struct btf_type").
The to-be-added "struct bpf_line_info" also has another
member, "insn_off" which is the same as the "insn_offset"
in "struct bpf_func_info". Hence, this patch renames "insn_offset"
to "insn_off" for "struct bpf_func_info".
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
1) When bpf_dump_raw_ok() == false and the kernel can provide >=1
func_info to the userspace, the current behavior is setting
the info.func_info_cnt to 0 instead of setting info.func_info
to 0.
It is different from the behavior in jited_func_lens/nr_jited_func_lens,
jited_ksyms/nr_jited_ksyms...etc.
This patch fixes it. (i.e. set func_info to 0 instead of
func_info_cnt to 0 when bpf_dump_raw_ok() == false).
2) When the userspace passed in info.func_info_cnt == 0, the kernel
will set the expected func_info size back to the
info.func_info_rec_size. It is a way for the userspace to learn
the kernel expected func_info_rec_size introduced in
commit 838e96904f ("bpf: Introduce bpf_func_info").
An exception is the kernel expected size is not set when
func_info is not available for a bpf_prog. This makes the
returned info.func_info_rec_size has different values
depending on the returned value of info.func_info_cnt.
This patch sets the kernel expected size to info.func_info_rec_size
independent of the info.func_info_cnt.
3) The current logic only rejects invalid func_info_rec_size if
func_info_cnt is non zero. This patch also rejects invalid
nonzero info.func_info_rec_size and not equal to the kernel
expected size.
4) Set info.btf_id as long as prog->aux->btf != NULL. That will
setup the later copy_to_user() codes look the same as others
which then easier to understand and maintain.
prog->aux->btf is not NULL only if prog->aux->func_info_cnt > 0.
Breaking up info.btf_id from prog->aux->func_info_cnt is needed
for the later line info patch anyway.
A similar change is made to bpf_get_prog_name().
Fixes: 838e96904f ("bpf: Introduce bpf_func_info")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Alexei Starovoitov says:
====================
pull-request: bpf 2018-12-05
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) fix bpf uapi pointers for 32-bit architectures, from Daniel.
2) improve verifer ability to handle progs with a lot of branches, from Alexei.
3) strict btf checks, from Yonghong.
4) bpf_sk_lookup api cleanup, from Joe.
5) other misc fixes
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
By default, BPF uses module_alloc() to allocate executable memory,
but this is not necessary on all arches and potentially undesirable
on some of them.
So break out the module_alloc() and module_memfree() calls into __weak
functions to allow them to be overridden in arch code.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
tk_core.seq is initialized open coded, but that misses to initialize the
lockdep map when lockdep is enabled. Lockdep splats involving tk_core seq
consequently lack a name and are hard to read.
Use the proper initializer which takes care of the lockdep map
initialization.
[ tglx: Massaged changelog ]
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: tj@kernel.org
Cc: johannes.berg@intel.com
Link: https://lkml.kernel.org/r/20181128234325.110011-12-bvanassche@acm.org
malicious bpf program may try to force the verifier to remember
a lot of distinct verifier states.
Put a limit to number of per-insn 'struct bpf_verifier_state'.
Note that hitting the limit doesn't reject the program.
It potentially makes the verifier do more steps to analyze the program.
It means that malicious programs will hit BPF_COMPLEXITY_LIMIT_INSNS sooner
instead of spending cpu time walking long link list.
The limit of BPF_COMPLEXITY_LIMIT_STATES==64 affects cilium progs
with slight increase in number of "steps" it takes to successfully verify
the programs:
before after
bpf_lb-DLB_L3.o 1940 1940
bpf_lb-DLB_L4.o 3089 3089
bpf_lb-DUNKNOWN.o 1065 1065
bpf_lxc-DDROP_ALL.o 28052 | 28162
bpf_lxc-DUNKNOWN.o 35487 | 35541
bpf_netdev.o 10864 10864
bpf_overlay.o 6643 6643
bpf_lcx_jit.o 38437 38437
But it also makes malicious program to be rejected in 0.4 seconds vs 6.5
Hence apply this limit to unprivileged programs only.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
pathological bpf programs may try to force verifier to explode in
the number of branch states:
20: (d5) if r1 s<= 0x24000028 goto pc+0
21: (b5) if r0 <= 0xe1fa20 goto pc+2
22: (d5) if r1 s<= 0x7e goto pc+0
23: (b5) if r0 <= 0xe880e000 goto pc+0
24: (c5) if r0 s< 0x2100ecf4 goto pc+0
25: (d5) if r1 s<= 0xe880e000 goto pc+1
26: (c5) if r0 s< 0xf4041810 goto pc+0
27: (d5) if r1 s<= 0x1e007e goto pc+0
28: (b5) if r0 <= 0xe86be000 goto pc+0
29: (07) r0 += 16614
30: (c5) if r0 s< 0x6d0020da goto pc+0
31: (35) if r0 >= 0x2100ecf4 goto pc+0
Teach verifier to recognize always taken and always not taken branches.
This analysis is already done for == and != comparison.
Expand it to all other branches.
It also helps real bpf programs to be verified faster:
before after
bpf_lb-DLB_L3.o 2003 1940
bpf_lb-DLB_L4.o 3173 3089
bpf_lb-DUNKNOWN.o 1080 1065
bpf_lxc-DDROP_ALL.o 29584 28052
bpf_lxc-DUNKNOWN.o 36916 35487
bpf_netdev.o 11188 10864
bpf_overlay.o 6679 6643
bpf_lcx_jit.o 39555 38437
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Malicious user space may try to force the verifier to use as much cpu
time and memory as possible. Hence check for pending signals
while verifying the program.
Note that suspend of sys_bpf(PROG_LOAD) syscall will lead to EAGAIN,
since the kernel has to release the resources used for program verification.
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Pull RCU changes from Paul E. McKenney:
- Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.
- Replace calls of RCU-bh and RCU-sched update-side functions
to their vanilla RCU counterparts. This series is a step
towards complete removal of the RCU-bh and RCU-sched update-side
functions.
( Note that some of these conversions are going upstream via their
respective maintainers. )
- Documentation updates, including a number of flavor-consolidation
updates from Joel Fernandes.
- Miscellaneous fixes.
- Automate generation of the initrd filesystem used for
rcutorture testing.
- Convert spin_is_locked() assertions to instead use lockdep.
( Note that some of these conversions are going upstream via their
respective maintainers. )
- SRCU updates, especially including a fix from Dennis Krein
for a bag-on-head-class bug.
- RCU torture-test updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since the vast majority of files (99.993% on a typical system) have no
fcaps, display "0" instead of the full zero-padded 16 hex digits in the
two PATH record cap_f* fields to save netlink bandwidth and disk space.
Simply changing the format to %x won't work since the value is two (or
possibly more in the future) 32-bit hexadecimal values concatenated and
bits in higher order values will be misrepresented.
Passes audit-testsuite and userspace tools already work fine.
Please see the github issue tracker for more details
https://github.com/linux-audit/audit-kernel/issues/101
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Acked-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Go over the scheduler source code and fix common typos
in comments - and a typo in an actual variable name.
No change in functionality intended.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix two typos in kernel/events/*.
No change in functionality intended.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The aux->func_info and aux->btf are leaked in the error out cases
during bpf_prog_load(). This patch fixes it.
Fixes: ba64e7d852 ("bpf: btf: support proper non-jit func info")
Cc: Yonghong Song <yhs@fb.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The "busted" rcutorture type is an intentionally broken implementation
of RCU. Doing forward-progress testing on this implementation is not
particularly meaningful on the one hand and can result in fatal abuse
of the memory allocator on the other. This commit therefore disables
forward-progress testing of the "busted" rcutorture type.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit narrows the scope of each bucket of the forward-progress
callback-invocation histograms from one second to 100 milliseconds, which
aids debugging of forward-progress problems by making shorter-duration
callback-invocation stalls visible.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit causes the OOM handler to do rcu_barrier() calls and to
free up forward-progress callbacks in order to recover from OOM events.
The current test is terminated, but subsequent forward-progress tests can
proceed. This allows a long test to result in multiple forward-progress
failures, greatly reducing the required testing time.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit prints the age of the forward-progress test in jiffies,
in order to allow better interpretation of the callback-invocation
histograms.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
If rcutorture's forward-progress tests fail while a grace period is not
in progress, it is useful to print the time since the last grace period
ended as a way to detect failure to launch a new grace period. This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
One reason why a forward-progress test might fail would be if something
prevented or delayed callback invocation. This commit therefore adds a
callback-invocation histogram printout when OOM is reported to rcutorture.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit prints out the non-zero per-CPU callback counts when a
forware-progress error (OOM event) occurs.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
[ paulmck: Fix a pair of uninitialized locals spotted by kbuild test robot. ]
The RCU CPU stall warnings print an estimate of the total number of
RCU callbacks queued in the system, but this estimate leaves out
the callbacks queued for nocbs CPUs. This commit therefore introduces
rcu_get_n_cbs_cpu(), which gives an accurate callback estimate for
both nocbs and normal CPUs, and uses this new function as needed.
This commit also introduces a rcu_get_n_cbs_nocb_cpu() helper function
that returns the number of callbacks for nocbs CPUs or zero otherwise,
and also uses this function in place of direct access to ->nocb_q_count
while in the area (fewer characters, you see).
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adds an OOM notifier during rcutorture forward-progress
testing. If this notifier is invoked, it dumps out some grace-period
state to help debug the forward-progress problem.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Because rcutorture's forward-progress checking will trigger from an
OOM notifier, this notifier will introduce asynchronous concurrent
access to the rcu_fwd_startat variable. This commit therefore prepares
for this by converting updates to WRITE_ONCE().
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Remove return variables (declared as "ret") in cases where,
depending on whether a condition evaluates as true, the result of a
function call can be immediately returned instead of storing the result in
the return variable. When the condition evaluates as false, the constant
initially stored in the return variable at declaration is returned instead.
Signed-off-by: Pierce Griffiths <pierceagriffiths@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit affinities the forward-progress tests to avoid hogging a
housekeeping CPU on the theory that the offloaded callbacks will be
running on those housekeeping CPUs.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
[ paulmck: Fix NULL-pointer issue located by kbuild test robot. ]
Tested-by: Rong Chen <rong.a.chen@intel.com>
This commit splits rcu_torture_fwd_prog_nr() and rcu_torture_fwd_prog_cr()
functions out of rcu_torture_fwd_prog() in order to reduce indentation
pain and because rcu_torture_fwd_prog() was getting a bit too long.
In addition, this will enable easier conditional execution of the
rcu_torture_fwd_prog_cr() function, which can give false-positive
failures in some NO_HZ_FULL configurations due to overloading the
housekeeping CPUs.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now that the forward-progress code does a full-bore continuous callback
flood lasting multiple seconds, there is little point in also posting a
mere 60,000 callbacks every second or so. This commit therefore removes
the old cbflood testing. Over time, it may be desirable to concurrently
do full-bore continuous callback floods on all CPUs simultaneously, but
one dragon at a time.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, the torture scripts rely on the initrd/init script to bring
any extra CPUs online, for example, in the case where the kernel and
qemu have different ideas about how many CPUs are present. This works,
but is an unnecessary dependency on initrd, which needs to vary depending
on the distro. This commit therefore causes torture_onoff() to check
for additional CPUs, attempting to bring any found online. Errors are
ignored, just as they are by the initrd/init script.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit adds a call_rcu() flooding loop to the forward-progress test.
This emulates tight userspace loops that force call_rcu() invocations,
for example, the infamous loop containing close(open()) that instigated
the addition of blimit. If RCU does not make sufficient forward progress
in invoking the resulting flood of callbacks, rcutorture emits a warning.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
bug.2018.11.12a: Get rid of BUG_ON() and friends
consolidate.2018.12.01a: Continued RCU flavor-consolidation cleanup
doc.2018.11.12a: Documentation updates
fixes.2018.11.12a: Miscellaneous fixes
initrd.2018.11.08b: Automate creation of rcutorture initrd
sil.2018.11.12a: Remove more spin_unlock_wait() calls
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu(). This commit therefore makes this change,
even though it is but a comment.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu(). This commit therefore makes this change,
even though it is but a comment.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Dennis Zhou (Facebook)" <dennisszhou@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Pull STIBP fallout fixes from Thomas Gleixner:
"The performance destruction department finally got it's act together
and came up with a cure for the STIPB regression:
- Provide a command line option to control the spectre v2 user space
mitigations. Default is either seccomp or prctl (if seccomp is
disabled in Kconfig). prctl allows mitigation opt-in, seccomp
enables the migitation for sandboxed processes.
- Rework the code to handle the conditional STIBP/IBPB control and
remove the now unused ptrace_may_access_sched() optimization
attempt
- Disable STIBP automatically when SMT is disabled
- Optimize the switch_to() logic to avoid MSR writes and invocations
of __switch_to_xtra().
- Make the asynchronous speculation TIF updates synchronous to
prevent stale mitigation state.
As a general cleanup this also makes retpoline directly depend on
compiler support and removes the 'minimal retpoline' option which just
pretended to provide some form of security while providing none"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
x86/speculation: Provide IBPB always command line options
x86/speculation: Add seccomp Spectre v2 user space protection mode
x86/speculation: Enable prctl mode for spectre_v2_user
x86/speculation: Add prctl() control for indirect branch speculation
x86/speculation: Prepare arch_smt_update() for PRCTL mode
x86/speculation: Prevent stale SPEC_CTRL msr content
x86/speculation: Split out TIF update
ptrace: Remove unused ptrace_may_access_sched() and MODE_IBRS
x86/speculation: Prepare for conditional IBPB in switch_mm()
x86/speculation: Avoid __switch_to_xtra() calls
x86/process: Consolidate and simplify switch_to_xtra() code
x86/speculation: Prepare for per task indirect branch speculation control
x86/speculation: Add command line control for indirect branch speculation
x86/speculation: Unify conditional spectre v2 print functions
x86/speculataion: Mark command line parser data __initdata
x86/speculation: Mark string arrays const correctly
x86/speculation: Reorder the spec_v2 code
x86/l1tf: Show actual SMT state
x86/speculation: Rework SMT state change
sched/smt: Expose sched_smt_present static key
...
Often we want to write tests cases that check things like bad context
offset accesses. And one way to do this is to use an odd offset on,
for example, a 32-bit load.
This unfortunately triggers the alignment checks first on platforms
that do not set CONFIG_EFFICIENT_UNALIGNED_ACCESS. So the test
case see the alignment failure rather than what it was testing for.
It is often not completely possible to respect the original intention
of the test, or even test the same exact thing, while solving the
alignment issue.
Another option could have been to check the alignment after the
context and other validations are performed by the verifier, but
that is a non-trivial change to the verifier.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge misc fixes from Andrew Morton:
"31 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (31 commits)
ocfs2: fix potential use after free
mm/khugepaged: fix the xas_create_range() error path
mm/khugepaged: collapse_shmem() do not crash on Compound
mm/khugepaged: collapse_shmem() without freezing new_page
mm/khugepaged: minor reorderings in collapse_shmem()
mm/khugepaged: collapse_shmem() remember to clear holes
mm/khugepaged: fix crashes due to misaccounted holes
mm/khugepaged: collapse_shmem() stop if punched or truncated
mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
mm/huge_memory: splitting set mapping+index before unfreeze
mm/huge_memory: rename freeze_page() to unmap_page()
initramfs: clean old path before creating a hardlink
kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace
psi: make disabling/enabling easier for vendor kernels
proc: fixup map_files test on arm
debugobjects: avoid recursive calls with kmemleak
userfaultfd: shmem: UFFDIO_COPY: set the page dirty if VM_WRITE is not set
userfaultfd: shmem: add i_size checks
userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas
userfaultfd: shmem: allocate anonymous memory for MAP_PRIVATE shmem
...
- Fix crash by not allowing kprobing of stackleak_erase() (Alexander Popov)
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Merge tag 'gcc-plugins-v4.20-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull stackleak plugin fix from Kees Cook:
"Fix crash by not allowing kprobing of stackleak_erase() (Alexander
Popov)"
* tag 'gcc-plugins-v4.20-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
stackleak: Disable function tracing and kprobes for stackleak_erase()
Since __sanitizer_cov_trace_pc() is marked as notrace, function calls in
__sanitizer_cov_trace_pc() shouldn't be traced either.
ftrace_graph_caller() gets called for each function that isn't marked
'notrace', like canonicalize_ip(). This is the call trace from a run:
[ 139.644550] ftrace_graph_caller+0x1c/0x24
[ 139.648352] canonicalize_ip+0x18/0x28
[ 139.652313] __sanitizer_cov_trace_pc+0x14/0x58
[ 139.656184] sched_clock+0x34/0x1e8
[ 139.659759] trace_clock_local+0x40/0x88
[ 139.663722] ftrace_push_return_trace+0x8c/0x1f0
[ 139.667767] prepare_ftrace_return+0xa8/0x100
[ 139.671709] ftrace_graph_caller+0x1c/0x24
Rework so that check_kcov_mode() and canonicalize_ip() that are called
from __sanitizer_cov_trace_pc() are also marked as notrace.
Link: http://lkml.kernel.org/r/20181128081239.18317-1-anders.roxell@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signen-off-by: Anders Roxell <anders.roxell@linaro.org>
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman reports a hackbench regression with psi that would prohibit
shipping the suse kernel with it default-enabled, but he'd still like
users to be able to opt in at little to no cost to others.
With the current combination of CONFIG_PSI and the psi_disabled bool set
from the commandline, this is a challenge. Do the following things to
make it easier:
1. Add a config option CONFIG_PSI_DEFAULT_DISABLED that allows distros
to enable CONFIG_PSI in their kernel but leave the feature disabled
unless a user requests it at boot-time.
To avoid double negatives, rename psi_disabled= to psi=.
2. Make psi_disabled a static branch to eliminate any branch costs
when the feature is disabled.
In terms of numbers before and after this patch, Mel says:
: The following is a comparision using CONFIG_PSI=n as a baseline against
: your patch and a vanilla kernel
:
: 4.20.0-rc4 4.20.0-rc4 4.20.0-rc4
: kconfigdisable-v1r1 vanilla psidisable-v1r1
: Amean 1 1.3100 ( 0.00%) 1.3923 ( -6.28%) 1.3427 ( -2.49%)
: Amean 3 3.8860 ( 0.00%) 4.1230 * -6.10%* 3.8860 ( -0.00%)
: Amean 5 6.8847 ( 0.00%) 8.0390 * -16.77%* 6.7727 ( 1.63%)
: Amean 7 9.9310 ( 0.00%) 10.8367 * -9.12%* 9.9910 ( -0.60%)
: Amean 12 16.6577 ( 0.00%) 18.2363 * -9.48%* 17.1083 ( -2.71%)
: Amean 18 26.5133 ( 0.00%) 27.8833 * -5.17%* 25.7663 ( 2.82%)
: Amean 24 34.3003 ( 0.00%) 34.6830 ( -1.12%) 32.0450 ( 6.58%)
: Amean 30 40.0063 ( 0.00%) 40.5800 ( -1.43%) 41.5087 ( -3.76%)
: Amean 32 40.1407 ( 0.00%) 41.2273 ( -2.71%) 39.9417 ( 0.50%)
:
: It's showing that the vanilla kernel takes a hit (as the bisection
: indicated it would) and that disabling PSI by default is reasonably
: close in terms of performance for this particular workload on this
: particular machine so;
Link: http://lkml.kernel.org/r/20181127165329.GA29728@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Change idx variable in DO_TRACE macro to __idx to avoid name conflicts.
A kvm event had "idx" as a parameter and it confused the macro.
- Fix a race where interrupts would be traced when set_graph_function was set.
The previous patch set increased a race window that tricked the function graph
tracer to think it should trace interrupts when it really should not have.
The bug has been there before, but was seldom hit. Only the last patch series
made it more common.
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Merge tag 'trace-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull more tracing fixes from Steven Rostedt:
"Two more fixes:
- Change idx variable in DO_TRACE macro to __idx to avoid name
conflicts. A kvm event had "idx" as a parameter and it confused the
macro.
- Fix a race where interrupts would be traced when set_graph_function
was set. The previous patch set increased a race window that
tricked the function graph tracer to think it should trace
interrupts when it really should not have.
The bug has been there before, but was seldom hit. Only the last
patch series made it more common"
* tag 'trace-v4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/fgraph: Fix set_graph_function from showing interrupts
tracepoint: Use __idx instead of idx in DO_TRACE macro to make it unique
was introduced by a patch that tried to fix one bug, but by doing so created
another bug. As both bugs corrupt the output (but they do not crash the
kernel), I decided to fix the design such that it could have both bugs
fixed. The original fix, fixed time reporting of the function graph tracer
when doing a max_depth of one. This was code that can test how much the
kernel interferes with userspace. But in doing so, it could corrupt the time
keeping of the function profiler.
The issue is that the curr_ret_stack variable was being used for two
different meanings. One was to keep track of the stack pointer on the
ret_stack (shadow stack used by the function graph tracer), and the other
use case was the graph call depth. Although, the two may be closely
related, where they got updated was the issue that lead to the two different
bugs that required the two use cases to be updated differently.
The big issue with this fix is that it requires changing each architecture.
The good news is, I was able to remove a lot of code that was duplicated
within the architectures and place it into a single location. Then I could
make the fix in one place.
I pushed this code into linux-next to let it settle over a week, and before
doing so, I cross compiled all the affected architectures to make sure that
they built fine.
In the mean time, I also pulled in a patch that fixes the sched_switch
previous tasks state output, that was not actually correct.
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Merge tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"While rewriting the function graph tracer, I discovered a design flaw
that was introduced by a patch that tried to fix one bug, but by doing
so created another bug.
As both bugs corrupt the output (but they do not crash the kernel), I
decided to fix the design such that it could have both bugs fixed. The
original fix, fixed time reporting of the function graph tracer when
doing a max_depth of one. This was code that can test how much the
kernel interferes with userspace. But in doing so, it could corrupt
the time keeping of the function profiler.
The issue is that the curr_ret_stack variable was being used for two
different meanings. One was to keep track of the stack pointer on the
ret_stack (shadow stack used by the function graph tracer), and the
other use case was the graph call depth. Although, the two may be
closely related, where they got updated was the issue that lead to the
two different bugs that required the two use cases to be updated
differently.
The big issue with this fix is that it requires changing each
architecture. The good news is, I was able to remove a lot of code
that was duplicated within the architectures and place it into a
single location. Then I could make the fix in one place.
I pushed this code into linux-next to let it settle over a week, and
before doing so, I cross compiled all the affected architectures to
make sure that they built fine.
In the mean time, I also pulled in a patch that fixes the sched_switch
previous tasks state output, that was not actually correct"
* tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
sched, trace: Fix prev_state output in sched_switch tracepoint
function_graph: Have profiler use curr_ret_stack and not depth
function_graph: Reverse the order of pushing the ret_stack and the callback
function_graph: Move return callback before update of curr_ret_stack
function_graph: Use new curr_ret_depth to manage depth instead of curr_ret_stack
function_graph: Make ftrace_push_return_trace() static
sparc/function_graph: Simplify with function_graph_enter()
sh/function_graph: Simplify with function_graph_enter()
s390/function_graph: Simplify with function_graph_enter()
riscv/function_graph: Simplify with function_graph_enter()
powerpc/function_graph: Simplify with function_graph_enter()
parisc: function_graph: Simplify with function_graph_enter()
nds32: function_graph: Simplify with function_graph_enter()
MIPS: function_graph: Simplify with function_graph_enter()
microblaze: function_graph: Simplify with function_graph_enter()
arm64: function_graph: Simplify with function_graph_enter()
ARM: function_graph: Simplify with function_graph_enter()
x86/function_graph: Simplify with function_graph_enter()
function_graph: Create function_graph_enter() to consolidate architecture code
The stackleak_erase() function is called on the trampoline stack at the
end of syscall. This stack is not big enough for ftrace and kprobes
operations, e.g. it can be exhausted if we use kprobe_events for
stackleak_erase().
So let's disable function tracing and kprobes of stackleak_erase().
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 10e9ae9fab ("gcc-plugins: Add STACKLEAK plugin for tracking the kernel stack")
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
The tracefs file set_graph_function is used to only function graph functions
that are listed in that file (or all functions if the file is empty). The
way this is implemented is that the function graph tracer looks at every
function, and if the current depth is zero and the function matches
something in the file then it will trace that function. When other functions
are called, the depth will be greater than zero (because the original
function will be at depth zero), and all functions will be traced where the
depth is greater than zero.
The issue is that when a function is first entered, and the handler that
checks this logic is called, the depth is set to zero. If an interrupt comes
in and a function in the interrupt handler is traced, its depth will be
greater than zero and it will automatically be traced, even if the original
function was not. But because the logic only looks at depth it may trace
interrupts when it should not be.
The recent design change of the function graph tracer to fix other bugs
caused the depth to be zero while the function graph callback handler is
being called for a longer time, widening the race of this happening. This
bug was actually there for a longer time, but because the race window was so
small it seldom happened. The Fixes tag below is for the commit that widen
the race window, because that commit belongs to a series that will also help
fix the original bug.
Cc: stable@kernel.org
Fixes: 39eb456dac ("function_graph: Use new curr_ret_depth to manage depth instead of curr_ret_stack")
Reported-by: Joe Lawrence <joe.lawrence@redhat.com>
Tested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
bpf-next 2018-11-30
The following pull-request contains BPF updates for your *net-next* tree.
(Getting out bit earlier this time to pull in a dependency from bpf.)
The main changes are:
1) Add libbpf ABI versioning and document API naming conventions
as well as ABI versioning process, from Andrey.
2) Add a new sk_msg_pop_data() helper for sk_msg based BPF
programs that is used in conjunction with sk_msg_push_data()
for adding / removing meta data to the msg data, from John.
3) Optimize convert_bpf_ld_abs() for 0 offset and fix various
lib and testsuite build failures on 32 bit, from David.
4) Make BPF prog dump for !JIT identical to how we dump subprogs
when JIT is in use, from Yonghong.
5) Rename btf_get_from_id() to make it more conform with libbpf
API naming conventions, from Martin.
6) Add a missing BPF kselftest config item, from Naresh.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The module loader internally works with both exported symbols
represented as struct kernel_symbol, as well as Elf symbols from a
module's symbol table. It's hard to distinguish sometimes which type of
symbol we're handling given that some helper function names are not
consistent or helpful. Take get_ksymbol() for instance - are we
looking for an exported symbol or a kallsyms symbol here? Or symname()
and kernel_symbol_name() - which function handles an exported symbol and
which one an Elf symbol?
Clean up and unify the function naming scheme a bit to make it clear
which kind of symbol we're handling. This change only affects static
functions internal to the module loader.
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
printk_emit() is called from only devkmsg_write() in the same file.
Save object size by making it a local function.
Link: http://lkml.kernel.org/r/5cc99d2c-c408-34f7-d1fc-e1cd2a9e31da@i-love.sakura.ne.jp
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Trivial conflict in net/core/filter.c, a locally computed
'sdif' is now an argument to the function.
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch added name checking for the following types:
. BTF_KIND_PTR, BTF_KIND_ARRAY, BTF_KIND_VOLATILE,
BTF_KIND_CONST, BTF_KIND_RESTRICT:
the name must be null
. BTF_KIND_STRUCT, BTF_KIND_UNION: the struct/member name
is either null or a valid identifier
. BTF_KIND_ENUM: the enum type name is either null or a valid
identifier; the enumerator name must be a valid identifier.
. BTF_KIND_FWD: the name must be a valid identifier
. BTF_KIND_TYPEDEF: the name must be a valid identifier
For those places a valid name is required, the name must be
a valid C identifier. This can be relaxed later if we found
use cases for a different (non-C) frontend.
Fixes: 69b693f0ae ("bpf: btf: Introduce BPF Type Format (BTF)")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Function btf_name_valid_identifier() have been implemented in
bpf-next commit 2667a2626f ("bpf: btf: Add BTF_KIND_FUNC and
BTF_KIND_FUNC_PROTO"). Backport this function so later patch
can use it.
Fixes: 69b693f0ae ("bpf: btf: Introduce BPF Type Format (BTF)")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull networking fixes from David Miller:
1) ARM64 JIT fixes for subprog handling from Daniel Borkmann.
2) Various sparc64 JIT bug fixes (fused branch convergance, frame
pointer usage detection logic, PSEODU call argument handling).
3) Fix to use BH locking in nf_conncount, from Taehee Yoo.
4) Fix race of TX skb freeing in ipheth driver, from Bernd Eckstein.
5) Handle return value of TX NAPI completion properly in lan743x
driver, from Bryan Whitehead.
6) MAC filter deletion in i40e driver clears wrong state bit, from
Lihong Yang.
7) Fix use after free in rionet driver, from Pan Bian.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (53 commits)
s390/qeth: fix length check in SNMP processing
net: hisilicon: remove unexpected free_netdev
rapidio/rionet: do not free skb before reading its length
i40e: fix kerneldoc for xsk methods
ixgbe: recognize 1000BaseLX SFP modules as 1Gbps
i40e: Fix deletion of MAC filters
igb: fix uninitialized variables
netfilter: nf_tables: deactivate expressions in rule replecement routine
lan743x: Enable driver to work with LAN7431
tipc: fix lockdep warning during node delete
lan743x: fix return value for lan743x_tx_napi_poll
net: via: via-velocity: fix spelling mistake "alignement" -> "alignment"
qed: fix spelling mistake "attnetion" -> "attention"
net: thunderx: fix NULL pointer dereference in nic_remove
sctp: increase sk_wmem_alloc when head->truesize is increased
firestream: fix spelling mistake: "Inititing" -> "Initializing"
net: phy: add workaround for issue where PHY driver doesn't bind to the device
usbnet: ipheth: fix potential recvmsg bug and recvmsg bug 2
sparc: Adjust bpf JIT prologue for PSEUDO calls.
bpf, doc: add entries of who looks over which jits
...
The IBPB control code in x86 removed the usage. Remove the functionality
which was introduced for this.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185005.559149393@linutronix.de
arch_smt_update() is only called when the sysfs SMT control knob is
changed. This means that when SMT is enabled in the sysfs control knob the
system is considered to have SMT active even if all siblings are offline.
To allow finegrained control of the speculation mitigations, the actual SMT
state is more interesting than the fact that siblings could be enabled.
Rework the code, so arch_smt_update() is invoked from each individual CPU
hotplug function, and simplify the update function while at it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185004.521974984@linutronix.de
Make the scheduler's 'sched_smt_present' static key globaly available, so
it can be used in the x86 speculation control code.
Provide a query function and a stub for the CONFIG_SMP=n case.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185004.430168326@linutronix.de
Currently the 'sched_smt_present' static key is enabled when at CPU bringup
SMT topology is observed, but it is never disabled. However there is demand
to also disable the key when the topology changes such that there is no SMT
present anymore.
Implement this by making the key count the number of cores that have SMT
enabled.
In particular, the SMT topology bits are set before interrrupts are enabled
and similarly, are cleared after interrupts are disabled for the last time
and the CPU dies.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20181125185004.246110444@linutronix.de
The profiler uses trace->depth to find its entry on the ret_stack, but the
depth may not match the actual location of where its entry is (if an
interrupt were to preempt the processing of the profiler for another
function, the depth and the curr_ret_stack will be different).
Have it use the curr_ret_stack as the index to find its ret_stack entry
instead of using the depth variable, as that is no longer guaranteed to be
the same.
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The function graph profiler uses the ret_stack to store the "subtime" and
reuse it by nested functions and also on the return. But the current logic
has the profiler callback called before the ret_stack is updated, and it is
just modifying the ret_stack that will later be allocated (it's just lucky
that the "subtime" is not touched when it is allocated).
This could also cause a crash if we are at the end of the ret_stack when
this happens.
By reversing the order of the allocating the ret_stack and then calling the
callbacks attached to a function being traced, the ret_stack entry is no
longer used before it is allocated.
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In the past, curr_ret_stack had two functions. One was to denote the depth
of the call graph, the other is to keep track of where on the ret_stack the
data is used. Although they may be slightly related, there are two cases
where they need to be used differently.
The one case is that it keeps the ret_stack data from being corrupted by an
interrupt coming in and overwriting the data still in use. The other is just
to know where the depth of the stack currently is.
The function profiler uses the ret_stack to save a "subtime" variable that
is part of the data on the ret_stack. If curr_ret_stack is modified too
early, then this variable can be corrupted.
The "max_depth" option, when set to 1, will record the first functions going
into the kernel. To see all top functions (when dealing with timings), the
depth variable needs to be lowered before calling the return hook. But by
lowering the curr_ret_stack, it makes the data on the ret_stack still being
used by the return hook susceptible to being overwritten.
Now that there's two variables to handle both cases (curr_ret_depth), we can
move them to the locations where they can handle both cases.
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently, the depth of the ret_stack is determined by curr_ret_stack index.
The issue is that there's a race between setting of the curr_ret_stack and
calling of the callback attached to the return of the function.
Commit 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling
trace return callback") moved the calling of the callback to after the
setting of the curr_ret_stack, even stating that it was safe to do so, when
in fact, it was the reason there was a barrier() there (yes, I should have
commented that barrier()).
Not only does the curr_ret_stack keep track of the current call graph depth,
it also keeps the ret_stack content from being overwritten by new data.
The function profiler, uses the "subtime" variable of ret_stack structure
and by moving the curr_ret_stack, it allows for interrupts to use the same
structure it was using, corrupting the data, and breaking the profiler.
To fix this, there needs to be two variables to handle the call stack depth
and the pointer to where the ret_stack is being used, as they need to change
at two different locations.
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As all architectures now call function_graph_enter() to do the entry work,
no architecture should ever call ftrace_push_return_trace(). Make it static.
This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In RCU, the distinction between "rsp", "rnp", and "rdp" has served well
for a great many years, but in SRCU, "sp" vs. "sdp" has proven confusing.
This commit therefore renames SRCU's "sp" pointers to "ssp", so that there
is "ssp" for srcu_struct pointer, "snp" for srcu_node pointer, and "sdp"
for srcu_data pointer.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The srcu_gp_start() function is called with the srcu_struct structure's
->lock held, but not with the srcu_data structure's ->lock. This is
problematic because this function accesses and updates the srcu_data
structure's ->srcu_cblist, which is protected by that lock. Failing to
hold this lock can result in corruption of the SRCU callback lists,
which in turn can result in arbitrarily bad results.
This commit therefore makes srcu_gp_start() acquire the srcu_data
structure's ->lock across the calls to rcu_segcblist_advance() and
rcu_segcblist_accelerate(), thus preventing this corruption.
Reported-by: Bart Van Assche <bvanassche@acm.org>
Reported-by: Christoph Hellwig <hch@infradead.org>
Reported-by: Sebastian Kuzminsky <seb.kuzminsky@gmail.com>
Signed-off-by: Dennis Krein <Dennis.Krein@netapp.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Tested-by: Dennis Krein <Dennis.Krein@netapp.com>
Cc: <stable@vger.kernel.org> # 4.16.x
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu(). This commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Now that call_rcu()'s callback is not invoked until after all
preempt-disable regions of code have completed (in addition to explicitly
marked RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_sched(). This commit therefore makes that change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can
be replaced by synchronize_rcu(). Similarly, call_rcu_sched() can be
replaced by call_rcu(). This commit therefore makes these changes.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu(). This commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu(). This commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu(). This commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can
be replaced by synchronize_rcu(). Similarly, call_rcu_sched() can be
replaced by call_rcu(). This commit therefore makes these changes.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <linux-kernel@vger.kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit 838e96904f ("bpf: Introduce bpf_func_info")
added bpf func info support. The userspace is able
to get better ksym's for bpf programs with jit, and
is able to print out func prototypes.
For a program containing func-to-func calls, the existing
implementation returns user specified number of function
calls and BTF types if jit is enabled. If the jit is not
enabled, it only returns the type for the main function.
This is undesirable. Interpreter may still be used
and we should keep feature identical regardless of
whether jit is enabled or not.
This patch fixed this discrepancy.
Fixes: 838e96904f ("bpf: Introduce bpf_func_info")
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Make fetching of the BPF call address from ppc64 JIT generic. ppc64
was using a slightly different variant rather than through the insns'
imm field encoding as the target address would not fit into that space.
Therefore, the target subprog number was encoded into the insns' offset
and fetched through fp->aux->func[off]->bpf_func instead. Given there
are other JITs with this issue and the mechanism of fetching the address
is JIT-generic, move it into the core as a helper instead. On the JIT
side, we get information on whether the retrieved address is a fixed
one, that is, not changing through JIT passes, or a dynamic one. For
the former, JITs can optimize their imm emission because this doesn't
change jump offsets throughout JIT process.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Tested-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There are many places, notably audit_log_task_info() and
audit_log_exit(), that take task_struct pointers but in reality they
are always working on the current task. This patch eliminates the
task_struct arguments and uses current directly which allows a number
of cleanups as well.
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
There are some cases where we are making multiple audit_log_format()
calls in a row, for no apparent reason. Squash these down to a
single audit_log_format() call whenever possible.
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Currently all the architectures do basically the same thing in preparing the
function graph tracer on entry to a function. This code can be pulled into a
generic location and then this will allow the function graph tracer to be
fixed, as well as extended.
Create a new function graph helper function_graph_enter() that will call the
hook function (ftrace_graph_entry) and the shadow stack operation
(ftrace_push_return_trace), and remove the need of the architecture code to
manage the shadow stack.
This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-11-26
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Extend BTF to support function call types and improve the BPF
symbol handling with this info for kallsyms and bpftool program
dump to make debugging easier, from Martin and Yonghong.
2) Optimize LPM lookups by making longest_prefix_match() handle
multiple bytes at a time, from Eric.
3) Adds support for loading and attaching flow dissector BPF progs
from bpftool, from Stanislav.
4) Extend the sk_lookup() helper to be supported from XDP, from Nitin.
5) Enable verifier to support narrow context loads with offset > 0
to adapt to LLVM code generation (currently only offset of 0 was
supported). Add test cases as well, from Andrey.
6) Simplify passing device functions for offloaded BPF progs by
adding callbacks to bpf_prog_offload_ops instead of ndo_bpf.
Also convert nfp and netdevsim to make use of them, from Quentin.
7) Add support for sock_ops based BPF programs to send events to
the perf ring-buffer through perf_event_output helper, from
Sowmini and Daniel.
8) Add read / write support for skb->tstamp from tc BPF and cg BPF
programs to allow for supporting rate-limiting in EDT qdiscs
like fq from BPF side, from Vlad.
9) Extend libbpf API to support map in map types and add test cases
for it as well to BPF kselftests, from Nikita.
10) Account the maximum packet offset accessed by a BPF program in
the verifier and use it for optimizing nfp JIT, from Jiong.
11) Fix error handling regarding kprobe_events in BPF sample loader,
from Daniel T.
12) Add support for queue and stack map type in bpftool, from David.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2018-11-25
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix an off-by-one bug when adjusting subprog start offsets after
patching, from Edward.
2) Fix several bugs such as overflow in size allocation in queue /
stack map creation, from Alexei.
3) Fix wrong IPv6 destination port byte order in bpf_sk_lookup_udp
helper, from Andrey.
4) Fix several bugs in bpftool such as preventing an infinite loop
in get_fdinfo, error handling and man page references, from Quentin.
5) Fix a warning in bpf_trace_printk() that wasn't catching an
invalid format string, from Martynas.
6) Fix a bug in BPF cgroup local storage where non-atomic allocation
was used in atomic context, from Roman.
7) Fix a NULL pointer dereference bug in bpftool from reallocarray()
error handling, from Jakub and Wen.
8) Add a copy of pkt_cls.h and tc_bpf.h uapi headers to the tools
include infrastructure so that bpftool compiles on older RHEL7-like
user space which does not ship these headers, from Yonghong.
9) Fix BPF kselftests for user space where to get ping test working
with ping6 and ping -6, from Li.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a spelling mistake in a btf_verifier_log_member message,
fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Building tags produces warning:
ctags: Warning: kernel/bpf/local_storage.c:10: null expansion of name pattern "\1"
Let's use the same fix as in commit 25528213fe ("tags: Fix DEFINE_PER_CPU
expansions"), even though it violates the usual code style.
Signed-off-by: Rustam Kovhaev <rkovhaev@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
A format string consisting of "%p" or "%s" followed by an invalid
specifier (e.g. "%p%\n" or "%s%") could pass the check which
would make format_decode (lib/vsprintf.c) to warn.
Fixes: 9c959c863f ("tracing: Allow BPF programs to call bpf_trace_printk()")
Reported-by: syzbot+1ec5c5ec949c4adaa0c4@syzkaller.appspotmail.com
Signed-off-by: Martynas Pumputis <m@lambda.lt>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The SPDX identifier defines the license of the file already. No need for
the boilerplate.
Remove also the completely outdated Montavista snail mail address.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lkml.kernel.org/r/20181031182253.479792883@linutronix.de
The SPDX identifier defines the license of the file already. No need for
the boilerplate.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Manfred Rudigier <manfred.rudigier@omicronenergy.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lkml.kernel.org/r/20181031182253.385909804@linutronix.de
The SPDX identifier defines the license of the file already. No need for
the boilerplate.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lkml.kernel.org/r/20181031182253.300140921@linutronix.de
The SPDX identifier defines the license of the file already. No need for
the boilerplate.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lkml.kernel.org/r/20181031182253.215825217@linutronix.de
The SPDX identifier defines the license of the files already. No need for
the boilerplates.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20181031182253.132458951@linutronix.de
The SPDX identifier is enough. Remove the license boilerplate.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lkml.kernel.org/r/20181031182253.047449481@linutronix.de
"For licencing details see kernel-base/COPYING" and similar license
references have no value over the SPDX identifier. Remove them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lkml.kernel.org/r/20181031182252.963632760@linutronix.de
Update the time(r) core files files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of the
full boiler plate text.
This work is based on a script and data from Philippe Ombredanne, Kate
Stewart and myself. The data has been created with two independent license
scanners and manual inspection.
The following files do not contain any direct license information and have
been omitted from the big initial SPDX changes:
timeconst.bc: The .bc files were not touched
time.c, timer.c, timekeeping.c: Licence was deduced from EXPORT_SYMBOL_GPL
As those files do not contain direct license references they fall under the
project license, i.e. GPL V2 only.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20181031182252.879109557@linutronix.de
Remove the pointless filenames in the top level comments. They have no
value at all and just occupy space. While at it tidy up some of the
comments and remove a stale one.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: David Riley <davidriley@chromium.org>
Cc: Colin Cross <ccross@android.com>
Cc: Mark Brown <broonie@kernel.org>
Link: https://lkml.kernel.org/r/20181031182252.794898238@linutronix.de
Commit:
142b18ddc8 ("uprobes: Fix handle_swbp() vs unregister() + register() race")
added the UPROBE_COPY_INSN flag, and corresponding smp_wmb() and smp_rmb()
memory barriers, to ensure that handle_swbp() uses fully-initialized
uprobes only.
However, the smp_rmb() is mis-placed: this barrier should be placed
after handle_swbp() has tested for the flag, thus guaranteeing that
(program-order) subsequent loads from the uprobe can see the initial
stores performed by prepare_uprobe().
Move the smp_rmb() accordingly. Also amend the comments associated
to the two memory barriers to indicate their actual locations.
Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@kernel.org
Fixes: 142b18ddc8 ("uprobes: Fix handle_swbp() vs unregister() + register() race")
Link: http://lkml.kernel.org/r/20181122161031.15179-1-andrea.parri@amarulasolutions.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
From printk()/serial console point of view panic() is special, because
it may force CPU to re-enter printk() or/and serial console driver.
Therefore, some of serial consoles drivers are re-entrant. E.g. 8250:
serial8250_console_write()
{
if (port->sysrq)
locked = 0;
else if (oops_in_progress)
locked = spin_trylock_irqsave(&port->lock, flags);
else
spin_lock_irqsave(&port->lock, flags);
...
}
panic() does set oops_in_progress via bust_spinlocks(1), so in theory
we should be able to re-enter serial console driver from panic():
CPU0
<NMI>
uart_console_write()
serial8250_console_write() // if (oops_in_progress)
// spin_trylock_irqsave()
call_console_drivers()
console_unlock()
console_flush_on_panic()
bust_spinlocks(1) // oops_in_progress++
panic()
<NMI/>
spin_lock_irqsave(&port->lock, flags) // spin_lock_irqsave()
serial8250_console_write()
call_console_drivers()
console_unlock()
printk()
...
However, this does not happen and we deadlock in serial console on
port->lock spinlock. And the problem is that console_flush_on_panic()
called after bust_spinlocks(0):
void panic(const char *fmt, ...)
{
bust_spinlocks(1);
...
bust_spinlocks(0);
console_flush_on_panic();
...
}
bust_spinlocks(0) decrements oops_in_progress, so oops_in_progress
can go back to zero. Thus even re-entrant console drivers will simply
spin on port->lock spinlock. Given that port->lock may already be
locked either by a stopped CPU, or by the very same CPU we execute
panic() on (for instance, NMI panic() on printing CPU) the system
deadlocks and does not reboot.
Fix this by removing bust_spinlocks(0), so oops_in_progress is always
set in panic() now and, thus, re-entrant console drivers will trylock
the port->lock instead of spinning on it forever, when we call them
from console_flush_on_panic().
Link: http://lkml.kernel.org/r/20181025101036.6823-1-sergey.senozhatsky@gmail.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Daniel Wang <wonderfly@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: linux-serial@vger.kernel.org
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
At LPC 2018 in Vancouver, Vlad Dumitrescu mentioned that longest_prefix_match()
has a high cost [1].
One reason for that cost is a loop handling one byte at a time.
We can handle more bytes at a time, if enough attention is paid
to endianness.
I was able to remove ~55 % of longest_prefix_match() cpu costs.
[1] https://linuxplumbersconf.org/event/2/contributions/88/attachments/76/87/lpc-bpf-2018-shaping.pdf
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vlad Dumitrescu <vladum@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
If swiotlb_bounce_page() failed, calling arch_sync_dma_for_device() may
lead to such delights as performing cache maintenance on whatever
address phys_to_virt(SWIOTLB_MAP_ERROR) looks like, which is typically
outside the kernel memory map and goes about as well as expected.
Don't do that.
Fixes: a4a4330db4 ("swiotlb: add support for non-coherent DMA")
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This patch added interface to load a program with the following
additional information:
. prog_btf_fd
. func_info, func_info_rec_size and func_info_cnt
where func_info will provide function range and type_id
corresponding to each function.
The func_info_rec_size is introduced in the UAPI to specify
struct bpf_func_info size passed from user space. This
intends to make bpf_func_info structure growable in the future.
If the kernel gets a different bpf_func_info size from userspace,
it will try to handle user request with part of bpf_func_info
it can understand. In this patch, kernel can understand
struct bpf_func_info {
__u32 insn_offset;
__u32 type_id;
};
If user passed a bpf func_info record size of 16 bytes, the
kernel can still handle part of records with the above definition.
If verifier agrees with function range provided by the user,
the bpf_prog ksym for each function will use the func name
provided in the type_id, which is supposed to provide better
encoding as it is not limited by 16 bytes program name
limitation and this is better for bpf program which contains
multiple subprograms.
The bpf_prog_info interface is also extended to
return btf_id, func_info, func_info_rec_size and func_info_cnt
to userspace, so userspace can print out the function prototype
for each xlated function. The insn_offset in the returned
func_info corresponds to the insn offset for xlated functions.
With other jit related fields in bpf_prog_info, userspace can also
print out function prototypes for each jited function.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch adds BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
to support the function debug info.
BTF_KIND_FUNC_PROTO must not have a name (i.e. !t->name_off)
and it is followed by >= 0 'struct bpf_param' objects to
describe the function arguments.
The BTF_KIND_FUNC must have a valid name and it must
refer back to a BTF_KIND_FUNC_PROTO.
The above is the conclusion after the discussion between
Edward Cree, Alexei, Daniel, Yonghong and Martin.
By combining BTF_KIND_FUNC and BTF_LIND_FUNC_PROTO,
a complete function signature can be obtained. It will be
used in the later patches to learn the function signature of
a running bpf program.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch breaks up btf_type_is_void() into
btf_type_is_void() and btf_type_is_fwd().
It also adds btf_type_nosize() to better describe it is
testing a type has nosize info.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a new flag BPF_F_ZERO_SEED, which forces a hash map
to initialize the seed to zero. This is useful when doing
performance analysis both on individual BPF programs, as
well as the kernel's hash table implementation.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Remove the CONFIG_AUDIT_WATCH and CONFIG_AUDIT_TREE config options since
they are both dependent on CONFIG_AUDITSYSCALL and force
CONFIG_FSNOTIFY.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
There are still a couple of places (mark and watch config changes) that
open code auid and ses fields in sequence in records instead of using
the audit_log_session_info() helper. Use the helper. Adjust the helper
to accommodate being the first fields. Passes audit-testsuite.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: fixed misspellings in the description]
Signed-off-by: Paul Moore <paul@paul-moore.com>
The audit_log_session_info() function is only used in kernel/audit*, so
move its prototype to kernel/audit.h
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Merge misc fixes from Andrew Morton:
"16 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/memblock.c: fix a typo in __next_mem_pfn_range() comments
mm, page_alloc: check for max order in hot path
scripts/spdxcheck.py: make python3 compliant
tmpfs: make lseek(SEEK_DATA/SEK_HOLE) return ENXIO with a negative offset
lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturn
mm/vmstat.c: fix NUMA statistics updates
mm/gup.c: fix follow_page_mask() kerneldoc comment
ocfs2: free up write context when direct IO failed
scripts/faddr2line: fix location of start_kernel in comment
mm: don't reclaim inodes with many attached pages
mm, memory_hotplug: check zone_movable in has_unmovable_pages
mm/swapfile.c: use kvzalloc for swap_info_struct allocation
MAINTAINERS: update OMAP MMC entry
hugetlbfs: fix kernel BUG at fs/hugetlbfs/inode.c:444!
kernel/sched/psi.c: simplify cgroup_move_task()
z3fold: fix possible reclaim races
Pull scheduler fix from Ingo Molnar:
"Fix an exec() related scalability/performance regression, which was
caused by incorrectly calculating load and migrating tasks on exec()
when they shouldn't be"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix cpu_util_wake() for 'execl' type workloads
The existing code triggered an invalid warning about 'rq' possibly being
used uninitialized. Instead of doing the silly warning suppression by
initializa it to NULL, refactor the code to bail out early instead.
Warning was:
kernel/sched/psi.c: In function `cgroup_move_task':
kernel/sched/psi.c:639:13: warning: `rq' may be used uninitialized in this function [-Wmaybe-uninitialized]
Link: http://lkml.kernel.org/r/20181103183339.8669-1-olof@lixom.net
Fixes: 2ce7135adc ("psi: cgroup support")
Signed-off-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When patching in a new sequence for the first insn of a subprog, the start
of that subprog does not change (it's the first insn of the sequence), so
adjust_subprog_starts should check start <= off (rather than < off).
Also added a test to test_verifier.c (it's essentially the syz reproducer).
Fixes: cc8b0b92a1 ("bpf: introduce function calls (function boundaries)")
Reported-by: syzbot+4fc427c7af994b0948be@syzkaller.appspotmail.com
Signed-off-by: Edward Cree <ecree@solarflare.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pointer offload is being null checked however the following statement
dereferences the potentially null pointer offload when assigning
offload->dev_state. Fix this by only assigning it if offload is not
null.
Detected by CoverityScan, CID#1475437 ("Dereference after null check")
Fixes: 00db12c3d1 ("bpf: call verifier_prep from its callback in struct bpf_offload_dev")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Trivial fix to clean up an indentation issue
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Notice that in this particular case, I replaced the code comments with
a proper "fall through" annotation, which is what GCC is expecting
to find.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Notice that in this particular case, I replaced the code comments with
a proper "fall through" annotation, which is what GCC is expecting
to find.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Replace the whole switch statement with a for loop. This makes the
code clearer and easy to read.
This also addresses the following Coverity warnings:
Addresses-Coverity-ID: 115090 ("Missing break in switch")
Addresses-Coverity-ID: 115091 ("Missing break in switch")
Addresses-Coverity-ID: 114700 ("Missing break in switch")
Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
[daniel.thompson@linaro.org: Tiny grammar change in description]
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
gcc 8.1.0 warns with:
kernel/debug/kdb/kdb_support.c: In function ‘kallsyms_symbol_next’:
kernel/debug/kdb/kdb_support.c:239:4: warning: ‘strncpy’ specified bound depends on the length of the source argument [-Wstringop-overflow=]
strncpy(prefix_name, name, strlen(name)+1);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/debug/kdb/kdb_support.c:239:31: note: length computed here
Use strscpy() with the destination buffer size, and use ellipses when
displaying truncated symbols.
v2: Use strscpy()
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Jonathan Toppins <jtoppins@redhat.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: kgdb-bugreport@lists.sourceforge.net
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Since commit ad67b74d24 ("printk: hash addresses printed with %p"),
all pointers printed with %p are printed with hashed addresses
instead of real addresses in order to avoid leaking addresses in
dmesg and syslog. But this applies to kdb too, with is unfortunate:
Entering kdb (current=0x(ptrval), pid 329) due to Keyboard Entry
kdb> ps
15 sleeping system daemon (state M) processes suppressed,
use 'ps A' to see all.
Task Addr Pid Parent [*] cpu State Thread Command
0x(ptrval) 329 328 1 0 R 0x(ptrval) *sh
0x(ptrval) 1 0 0 0 S 0x(ptrval) init
0x(ptrval) 3 2 0 0 D 0x(ptrval) rcu_gp
0x(ptrval) 4 2 0 0 D 0x(ptrval) rcu_par_gp
0x(ptrval) 5 2 0 0 D 0x(ptrval) kworker/0:0
0x(ptrval) 6 2 0 0 D 0x(ptrval) kworker/0:0H
0x(ptrval) 7 2 0 0 D 0x(ptrval) kworker/u2:0
0x(ptrval) 8 2 0 0 D 0x(ptrval) mm_percpu_wq
0x(ptrval) 10 2 0 0 D 0x(ptrval) rcu_preempt
The whole purpose of kdb is to debug, and for debugging real addresses
need to be known. In addition, data displayed by kdb doesn't go into
dmesg.
This patch replaces all %p by %px in kdb in order to display real
addresses.
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Cc: <stable@vger.kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
On a powerpc 8xx, 'btc' fails as follows:
Entering kdb (current=0x(ptrval), pid 282) due to Keyboard Entry
kdb> btc
btc: cpu status: Currently on cpu 0
Available cpus: 0
kdb_getarea: Bad address 0x0
when booting the kernel with 'debug_boot_weak_hash', it fails as well
Entering kdb (current=0xba99ad80, pid 284) due to Keyboard Entry
kdb> btc
btc: cpu status: Currently on cpu 0
Available cpus: 0
kdb_getarea: Bad address 0xba99ad80
On other platforms, Oopses have been observed too, see
https://github.com/linuxppc/linux/issues/139
This is due to btc calling 'btt' with %p pointer as an argument.
This patch replaces %p by %px to get the real pointer value as
expected by 'btt'
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Cc: <stable@vger.kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
lockdep_assert_held() is better suited to checking locking requirements,
since it only checks if the current thread holds the lock regardless of
whether someone else does. This is also a step towards possibly removing
spin_is_locked().
Signed-off-by: Lance Roy <ldr709@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Subtracting INT_MIN can be interpreted as unconditional signed integer
overflow, which according to the C standard is undefined behavior.
Therefore, kernel build arguments notwithstanding, it would be good to
future-proof the code. This commit therefore substitutes INT_MAX for
INT_MIN in order to avoid undefined behavior.
While in the neighborhood, this commit also creates some meaningful names
for INT_MAX and friends in order to improve readability, as suggested
by Joel Fernandes.
Reported-by: Ran Rozenstein <ranro@mellanox.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Because __this_cpu_read() can be lighter weight than equivalent uses of
this_cpu_ptr(), this commit replaces the latter with the former.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
In PREEMPT kernels, an expedited grace period might send an IPI to a
CPU that is executing an RCU read-side critical section. In that case,
it would be nice if the rcu_read_unlock() directly interacted with the
RCU core code to immediately report the quiescent state. And this does
happen in the case where the reader has been preempted. But it would
also be a nice performance optimization if immediate reporting also
happened in the preemption-free case.
This commit therefore adds an ->exp_hint field to the task_struct structure's
->rcu_read_unlock_special field. The IPI handler sets this hint when
it has interrupted an RCU read-side critical section, and this causes
the outermost rcu_read_unlock() call to invoke rcu_read_unlock_special(),
which, if preemption is enabled, reports the quiescent state immediately.
If preemption is disabled, then the report is required to be deferred
until preemption (or bottom halves or interrupts or whatever) is re-enabled.
Because this is a hint, it does nothing for more complicated cases. For
example, if the IPI interrupts an RCU reader, but interrupts are disabled
across the rcu_read_unlock(), but another rcu_read_lock() is executed
before interrupts are re-enabled, the hint will already have been cleared.
If you do crazy things like this, reporting will be deferred until some
later RCU_SOFTIRQ handler, context switch, cond_resched(), or similar.
Reported-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Currently, rcu_gp_cleanup() traces the end of the old grace period after
the old grace period has officially ended. This might make intuitive
sense, but it also makes for confusing event-trace output because the
"end" trace displays not the old but instead the new grace-period number.
This commit therefore traces the end of an old grace period just before
that grace period officially ends.
Reported-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Because RCU avoids interrupting idle CPUs, rcu_is_watching() is used to
test whether or not it is currently legal to run RCU read-side critical
sections on this CPU. However, the first sentence and last sentences
of current comment for rcu_is_watching have opposite meaning of what
is expected. This commit therefore fixes this header comment.
Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adds a printout of the number of jiffies since the last time
that the RCU grace-period kthread did any processing. This can be useful
when tracking down forward-progress issues.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adds the name of the RCU grace-period state to
the show_rcu_gp_kthreads() output in order to ease debugging.
This commit also moves gp_state_getname() up in the code so that
show_rcu_gp_kthreads() can use it.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
In order to debug forward-progress stalls, it is necessary to check
for excessively delayed grace-period starts. This is currently done
for RCU CPU stall warnings by rcu_check_gp_start_stall(), which checks
to see if the start of a requested grace period has been delayed by an
RCU CPU stall warning period. Because rcutorture will need to check
for the time consumed by an RCU forward-progress delay, this commit
promotes gpssdelay from a local variable to a formal parameter. It is
not necessary to export rcu_check_gp_start_stall() because rcutorture
will access it via a wrapper function.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The rcu_check_gp_start_stall() function multiplies the return value
from rcu_jiffies_till_stall_check() by HZ, but the units are already
in jiffies. This commit therefore avoids the need for introduction of
a jiffies-squared unit by removing the extraneous multiplication.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The update.c file has a number of calls to BUG_ON(), which panics the
kernel, which is not a good strategy for devices (like embedded) that
don't have a way to capture console output. This commit therefore
converts these BUG_ON() calls to WARN_ON_ONCE() and WARN_ONCE().
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The tree_plugin.h file has a number of calls to BUG_ON(), which panics
the kernel, which is not a good strategy for devices (like embedded)
that don't have a way to capture console output. This commit therefore
converts these BUG_ON() calls to WARN_ON_ONCE() and WARN_ONCE().
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
[ paulmck: Fix typo: s/rcuo/rcub/. ]
Variables pointing to fsnotify_mark are sometimes called 'entry' and
sometimes 'mark'. Use 'mark' in all places.
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
[PM: minor merge fuzz due to updated patches previously in the series]
Signed-off-by: Paul Moore <paul@paul-moore.com>
