Pull networking fixes from David Miller:
"Nothing earth shattering here, lots of small fixes (f.e. missing RCU
protection, bad ref counting, missing memset(), etc.) all over the
place:
1) Use get_file_rcu() in task_file iterator, from Yonghong Song.
2) There are two ways to set remote source MAC addresses in macvlan
driver, but only one of which validates things properly. Fix this.
From Alvin Šipraga.
3) Missing of_node_put() in gianfar probing, from Sumera
Priyadarsini.
4) Preserve device wanted feature bits across multiple netlink
ethtool requests, from Maxim Mikityanskiy.
5) Fix rcu_sched stall in task and task_file bpf iterators, from
Yonghong Song.
6) Avoid reset after device destroy in ena driver, from Shay
Agroskin.
7) Missing memset() in netlink policy export reallocation path, from
Johannes Berg.
8) Fix info leak in __smc_diag_dump(), from Peilin Ye.
9) Decapsulate ECN properly for ipv6 in ipv4 tunnels, from Mark
Tomlinson.
10) Fix number of data stream negotiation in SCTP, from David Laight.
11) Fix double free in connection tracker action module, from Alaa
Hleihel.
12) Don't allow empty NHA_GROUP attributes, from Nikolay Aleksandrov"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (46 commits)
net: nexthop: don't allow empty NHA_GROUP
bpf: Fix two typos in uapi/linux/bpf.h
net: dsa: b53: check for timeout
tipc: call rcu_read_lock() in tipc_aead_encrypt_done()
net/sched: act_ct: Fix skb double-free in tcf_ct_handle_fragments() error flow
net: sctp: Fix negotiation of the number of data streams.
dt-bindings: net: renesas, ether: Improve schema validation
gre6: Fix reception with IP6_TNL_F_RCV_DSCP_COPY
hv_netvsc: Fix the queue_mapping in netvsc_vf_xmit()
hv_netvsc: Remove "unlikely" from netvsc_select_queue
bpf: selftests: global_funcs: Check err_str before strstr
bpf: xdp: Fix XDP mode when no mode flags specified
selftests/bpf: Remove test_align leftovers
tools/resolve_btfids: Fix sections with wrong alignment
net/smc: Prevent kernel-infoleak in __smc_diag_dump()
sfc: fix build warnings on 32-bit
net: phy: mscc: Fix a couple of spelling mistakes "spcified" -> "specified"
libbpf: Fix map index used in error message
net: gemini: Fix missing free_netdev() in error path of gemini_ethernet_port_probe()
net: atlantic: Use readx_poll_timeout() for large timeout
...
Pull kvm fixes from Paolo Bonzini:
- PAE and PKU bugfixes for x86
- selftests fix for new binutils
- MMU notifier fix for arm64
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: arm64: Only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is not set
KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()
kvm: x86: Toggling CR4.PKE does not load PDPTEs in PAE mode
kvm: x86: Toggling CR4.SMAP does not load PDPTEs in PAE mode
KVM: x86: fix access code passed to gva_to_gpa
selftests: kvm: Use a shorter encoding to clear RAX
Alexei Starovoitov says:
====================
pull-request: bpf 2020-08-21
The following pull-request contains BPF updates for your *net* tree.
We've added 11 non-merge commits during the last 5 day(s) which contain
a total of 12 files changed, 78 insertions(+), 24 deletions(-).
The main changes are:
1) three fixes in BPF task iterator logic, from Yonghong.
2) fix for compressed dwarf sections in vmlinux, from Jiri.
3) fix xdp attach regression, from Andrii.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The error path in libbpf.c:load_program() has calls to pr_warn()
which ends up for global_funcs tests to
test_global_funcs.c:libbpf_debug_print().
For the tests with no struct test_def::err_str initialized with a
string, it causes call of strstr() with NULL as the second argument
and it segfaults.
Fix it by calling strstr() only for non-NULL err_str.
Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200820115843.39454-1-yauheni.kaliuta@redhat.com
On ppc64le we get the following warning:
In file included from btf_dump.c:16:0:
btf_dump.c: In function ‘btf_dump_emit_struct_def’:
../include/linux/kernel.h:20:17: error: comparison of distinct pointer types lacks a cast [-Werror]
(void) (&_max1 == &_max2); \
^
btf_dump.c:882:11: note: in expansion of macro ‘max’
m_sz = max(0LL, btf__resolve_size(d->btf, m->type));
^~~
Fix by explicitly casting to __s64, which is a return type from
btf__resolve_size().
Fixes: 702eddc77a ("libbpf: Handle GCC built-in types for Arm NEON")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200818164456.1181661-1-andriin@fb.com
Pull networking fixes from David Miller:
"Another batch of fixes:
1) Remove nft_compat counter flush optimization, it generates warnings
from the refcount infrastructure. From Florian Westphal.
2) Fix BPF to search for build id more robustly, from Jiri Olsa.
3) Handle bogus getopt lengths in ebtables, from Florian Westphal.
4) Infoleak and other fixes to j1939 CAN driver, from Eric Dumazet and
Oleksij Rempel.
5) Reset iter properly on mptcp sendmsg() error, from Florian
Westphal.
6) Show a saner speed in bonding broadcast mode, from Jarod Wilson.
7) Various kerneldoc fixes in bonding and elsewhere, from Lee Jones.
8) Fix double unregister in bonding during namespace tear down, from
Cong Wang.
9) Disable RP filter during icmp_redirect selftest, from David Ahern"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (75 commits)
otx2_common: Use devm_kcalloc() in otx2_config_npa()
net: qrtr: fix usage of idr in port assignment to socket
selftests: disable rp_filter for icmp_redirect.sh
Revert "net: xdp: pull ethernet header off packet after computing skb->protocol"
phylink: <linux/phylink.h>: fix function prototype kernel-doc warning
mptcp: sendmsg: reset iter on error redux
net: devlink: Remove overzealous WARN_ON with snapshots
tipc: not enable tipc when ipv6 works as a module
tipc: fix uninit skb->data in tipc_nl_compat_dumpit()
net: Fix potential wrong skb->protocol in skb_vlan_untag()
net: xdp: pull ethernet header off packet after computing skb->protocol
ipvlan: fix device features
bonding: fix a potential double-unregister
can: j1939: add rxtimer for multipacket broadcast session
can: j1939: abort multipacket broadcast session when timeout occurs
can: j1939: cancel rxtimer on multipacket broadcast session complete
can: j1939: fix support for multipacket broadcast message
net: fddi: skfp: cfm: Remove seemingly unused variable 'ID_sccs'
net: fddi: skfp: cfm: Remove set but unused variable 'oldstate'
net: fddi: skfp: smt: Remove seemingly unused variable 'ID_sccs'
...
h1 is initially configured to reach h2 via r1 rather than the
more direct path through r2. If rp_filter is set and inherited
for r2, forwarding fails since the source address of h1 is
reachable from eth0 vs the packet coming to it via r1 and eth1.
Since rp_filter setting affects the test, explicitly reset it.
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If debug_regs.c is built with newer binutils, the resulting binary is "optimized"
by the assembler:
asm volatile("ss_start: "
"xor %%rax,%%rax\n\t"
"cpuid\n\t"
"movl $0x1a0,%%ecx\n\t"
"rdmsr\n\t"
: : : "rax", "ecx");
is translated to :
000000000040194e <ss_start>:
40194e: 31 c0 xor %eax,%eax <----- rax->eax?
401950: 0f a2 cpuid
401952: b9 a0 01 00 00 mov $0x1a0,%ecx
401957: 0f 32 rdmsr
As you can see rax is replaced with eax in target binary code.
This causes a difference is the length of xor instruction (2 Byte vs 3 Byte),
and makes the hard-coded instruction length check fail:
/* Instruction lengths starting at ss_start */
int ss_size[4] = {
3, /* xor */ <-------- 2 or 3?
2, /* cpuid */
5, /* mov */
2, /* rdmsr */
};
Encode the shorter version directly and, while at it, fix the "clobbers"
of the asm.
Cc: stable@vger.kernel.org
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
1) Endianness issue in IPv4 option support in nft_exthdr,
from Stephen Suryaputra.
2) Removes the waitcount optimization in nft_compat,
from Florian Westphal.
3) Remove ipv6 -> nf_defrag_ipv6 module dependency, from
Florian Westphal.
4) Memleak in chain binding support, also from Florian.
5) Simplify nft_flowtable.sh selftest, from Fabian Frederick.
6) Optional MTU arguments for selftest nft_flowtable.sh,
also from Fabian.
7) Remove noise error report when killing process in
selftest nft_flowtable.sh, from Fabian Frederick.
8) Reject bogus getsockopt option length in ebtables,
from Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull arch/sh updates from Rich Felker:
"Cleanup, SECCOMP_FILTER support, message printing fixes, and other
changes to arch/sh"
* tag 'sh-for-5.9' of git://git.libc.org/linux-sh: (34 commits)
sh: landisk: Add missing initialization of sh_io_port_base
sh: bring syscall_set_return_value in line with other architectures
sh: Add SECCOMP_FILTER
sh: Rearrange blocks in entry-common.S
sh: switch to copy_thread_tls()
sh: use the generic dma coherent remap allocator
sh: don't allow non-coherent DMA for NOMMU
dma-mapping: consolidate the NO_DMA definition in kernel/dma/Kconfig
sh: unexport register_trapped_io and match_trapped_io_handler
sh: don't include <asm/io_trapped.h> in <asm/io.h>
sh: move the ioremap implementation out of line
sh: move ioremap_fixed details out of <asm/io.h>
sh: remove __KERNEL__ ifdefs from non-UAPI headers
sh: sort the selects for SUPERH alphabetically
sh: remove -Werror from Makefiles
sh: Replace HTTP links with HTTPS ones
arch/sh/configs: remove obsolete CONFIG_SOC_CAMERA*
sh: stacktrace: Remove stacktrace_ops.stack()
sh: machvec: Modernize printing of kernel messages
sh: pci: Modernize printing of kernel messages
...
Pull more perf tools updates from Arnaldo Carvalho de Melo:
"Fixes:
- Fixes for 'perf bench numa'.
- Always memset source before memcpy in 'perf bench mem'.
- Quote CC and CXX for their arguments to fix build in environments
using those variables to pass more than just the compiler names.
- Fix module symbol processing, addressing regression detected via
"perf test".
- Allow multiple probes in record+script_probe_vfs_getname.sh 'perf
test' entry.
Improvements:
- Add script to autogenerate socket family name id->string table from
copy of kernel header, used so far in 'perf trace'.
- 'perf ftrace' improvements to provide similar options for this
utility so that one can go from 'perf record', 'perf trace', etc to
'perf ftrace' just by changing the name of the subcommand.
- Prefer new "sched:sched_waking" trace event when it exists in 'perf
sched' post processing.
- Update POWER9 metrics to utilize other metrics.
- Fall back to querying debuginfod if debuginfo not found locally.
Miscellaneous:
- Sync various kvm headers with kernel sources"
* tag 'perf-tools-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (40 commits)
perf ftrace: Make option description initials all capital letters
perf build-ids: Fall back to debuginfod query if debuginfo not found
perf bench numa: Remove dead code in parse_nodes_opt()
perf stat: Update POWER9 metrics to utilize other metrics
perf ftrace: Add change log
perf: ftrace: Add set_tracing_options() to set all trace options
perf ftrace: Add option --tid to filter by thread id
perf ftrace: Add option -D/--delay to delay tracing
perf: ftrace: Allow set graph depth by '--graph-opts'
perf ftrace: Add support for trace option tracing_thresh
perf ftrace: Add option 'verbose' to show more info for graph tracer
perf ftrace: Add support for tracing option 'irq-info'
perf ftrace: Add support for trace option funcgraph-irqs
perf ftrace: Add support for trace option sleep-time
perf ftrace: Add support for tracing option 'func_stack_trace'
perf tools: Add general function to parse sublevel options
perf ftrace: Add option '--inherit' to trace children processes
perf ftrace: Show trace column header
perf ftrace: Add option '-m/--buffer-size' to set per-cpu buffer size
perf ftrace: Factor out function write_tracing_file_int()
...
Daniel Borkmann says:
====================
pull-request: bpf 2020-08-15
The following pull-request contains BPF updates for your *net* tree.
We've added 23 non-merge commits during the last 4 day(s) which contain
a total of 32 files changed, 421 insertions(+), 141 deletions(-).
The main changes are:
1) Fix sock_ops ctx access splat due to register override, from John Fastabend.
2) Batch of various fixes to libbpf, bpftool, and selftests when testing build
in 32-bit mode, from Andrii Nakryiko.
3) Fix vmlinux.h generation on ARM by mapping GCC built-in types (__Poly*_t)
to equivalent ones clang can work with, from Jean-Philippe Brucker.
4) Fix build_id lookup in bpf_get_stackid() helper by walking all NOTE ELF
sections instead of just first, from Jiri Olsa.
5) Avoid use of __builtin_offsetof() in libbpf for CO-RE, from Yonghong Song.
6) Fix segfault in test_mmap due to inconsistent length params, from Jianlin Lv.
7) Don't override errno in libbpf when logging errors, from Toke Høiland-Jørgensen.
8) Fix v4_to_v6 sockaddr conversion in sk_lookup test, from Stanislav Fomichev.
9) Add link to bpf-helpers(7) man page to BPF doc, from Joe Stringer.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
During a perf-record, use the -ldebuginfod API to query a debuginfod
server, should the debug data not be found in the usual system
locations. If successful, the usual $HOME/.debug dir is populated.
Tested with:
$ find .
.
./ctags-debuginfo-5.8-26.fc31.x86_64.rpm
./usr
./usr/lib
./usr/lib/debug
./usr/lib/debug/.build-id
./usr/lib/debug/.build-id/ca
./usr/lib/debug/.build-id/ca/46f6ae6a0cee57d85abc1d461c49074248908d
./usr/lib/debug/.build-id/ca/46f6ae6a0cee57d85abc1d461c49074248908d.debug
./usr/lib/debug/usr
./usr/lib/debug/usr/bin
./usr/lib/debug/usr/bin/ctags-5.8-26.fc31.x86_64.debug
$ debuginfod -F .
...
$ rm -rf ~/.debug/ ; mkdir ~/.debug
$ perf record make tags
BUILD: Doing 'make -j8' parallel build
GEN tags
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.107 MB perf.data (1483 samples) ]
$ find ~/.debug | grep ctags
/home/jolsa/.debug/usr/bin/ctags
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/elf
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/probes
$ rm -rf ~/.debug/ ; mkdir ~/.debug
$ DEBUGINFOD_URLS=http://localhost:8002 perf record make tags
BUILD: Doing 'make -j8' parallel build
GEN tags
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.108 MB perf.data (1531 samples) ]
$ find ~/.debug | grep ctag
/home/jolsa/.debug/usr/bin/ctags
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/debug
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/elf
/home/jolsa/.debug/usr/bin/ctags/ca46f6ae6a0cee57d85abc1d461c49074248908d/probes
Note the 'debug' file is created in the last run.
Note that currently the debuginfo data are downloaded only on record path,
we still need add this support to perf build-id/report.. and test ;-)
Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Frank Ch. Eigler <fche@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This adds an option '-m/--buffer-size' to allow us set the size of per-cpu
tracing buffer.
Committer testing:
Before running with this option:
# find /sys/kernel/tracing/ -name buffer_size_kb | xargs cat
1408
1408
1408
1408
1408
1408
1408
1408
1408
#
Then, run:
# perf ftrace -m 2048K | head -10
2) | mutex_unlock() {
2) ==========> |
2) | smp_irq_work_interrupt() {
2) | irq_enter() {
2) 0.121 us | rcu_irq_enter();
2) 0.128 us | irqtime_account_irq();
2) 0.719 us | }
2) | __wake_up() {
2) | __wake_up_common_lock() {
2) 0.105 us | _raw_spin_lock_irqsave();
#
Now look at those tracefs knobs:
# find /sys/kernel/tracing/ -name buffer_size_kb | xargs cat
2048
2048
2048
2048
2048
2048
2048
2048
2048
#
This should be similar to the -m option in the other perf tools, such as
'perf record', 'perf trace', etc.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lore.kernel.org/lkml/20200808023141.14227-5-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This adds an option '-F/--funcs' to list all available functions to
trace, which is read from tracing file 'available_filter_functions'.
$ sudo ./perf ftrace -F | head
trace_initcall_finish_cb
initcall_blacklisted
do_one_initcall
do_one_initcall
trace_initcall_start_cb
run_init_process
try_to_run_init_process
match_dev_by_label
match_dev_by_uuid
rootfs_init_fs_context
$
Committer notes:
This is the same command line option and for the same purpose as in
'perf probe'.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lore.kernel.org/lkml/20200808023141.14227-3-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The '-g/-G' options have already implied function_graph tracer should be
used instead of function tracer. So we don't need extra option
'--tracer' in this case.
This patch changes the behavior as below:
- If '-g' or '-G' option is on, then function_graph tracer is used.
- If '-T' or '-N' option is on, then function tracer is used.
- The function_graph has priority over function tracer.
- The option '--tracer' only take effect if neither -g/-G nor -T/-N
is specified.
Here are some examples.
This will start tracing all functions using default tracer:
$ sudo perf ftrace
This will trace all functions using function graph tracer:
$ sudo perf ftrace -G '*'
This will trace function vfs_read using function graph tracer:
$ sudo perf ftrace -G vfs_read
This will trace function vfs_read using function tracer:
$ sudo perf ftrace -T vfs_read
Committer notes:
Using '-h -G' will tell what that option is about, so to further clarify
the above examples:
# perf ftrace -h -G
-G, --graph-funcs <func> Set graph filter on given functions
# perf ftrace -h -g
-g, --nograph-funcs <func> Set nograph filter on given functions
# perf ftrace -h -T
-T, --trace-funcs <func> trace given functions only
# perf ftrace -h -N
-N, --notrace-funcs <func> do not trace given functions
#
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lore.kernel.org/lkml/20200808023141.14227-2-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull networking fixes from David Miller:
"Some merge window fallout, some longer term fixes:
1) Handle headroom properly in lapbether and x25_asy drivers, from
Xie He.
2) Fetch MAC address from correct r8152 device node, from Thierry
Reding.
3) In the sw kTLS path we should allow MSG_CMSG_COMPAT in sendmsg,
from Rouven Czerwinski.
4) Correct fdputs in socket layer, from Miaohe Lin.
5) Revert troublesome sockptr_t optimization, from Christoph Hellwig.
6) Fix TCP TFO key reading on big endian, from Jason Baron.
7) Missing CAP_NET_RAW check in nfc, from Qingyu Li.
8) Fix inet fastreuse optimization with tproxy sockets, from Tim
Froidcoeur.
9) Fix 64-bit divide in new SFC driver, from Edward Cree.
10) Add a tracepoint for prandom_u32 so that we can more easily
perform usage analysis. From Eric Dumazet.
11) Fix rwlock imbalance in AF_PACKET, from John Ogness"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (49 commits)
net: openvswitch: introduce common code for flushing flows
af_packet: TPACKET_V3: fix fill status rwlock imbalance
random32: add a tracepoint for prandom_u32()
Revert "ipv4: tunnel: fix compilation on ARCH=um"
net: accept an empty mask in /sys/class/net/*/queues/rx-*/rps_cpus
net: ethernet: stmmac: Disable hardware multicast filter
net: stmmac: dwmac1000: provide multicast filter fallback
ipv4: tunnel: fix compilation on ARCH=um
vsock: fix potential null pointer dereference in vsock_poll()
sfc: fix ef100 design-param checking
net: initialize fastreuse on inet_inherit_port
net: refactor bind_bucket fastreuse into helper
net: phy: marvell10g: fix null pointer dereference
net: Fix potential memory leak in proto_register()
net: qcom/emac: add missed clk_disable_unprepare in error path of emac_clks_phase1_init
ionic_lif: Use devm_kcalloc() in ionic_qcq_alloc()
net/nfc/rawsock.c: add CAP_NET_RAW check.
hinic: fix strncpy output truncated compile warnings
drivers/net/wan/x25_asy: Added needed_headroom and a skb->len check
net/tls: Fix kmap usage
...
Despite bpftool generating data section memory layout that will work for
32-bit architectures on user-space side, BPF programs should be careful to not
use ambiguous types like `long`, which have different size in 32-bit and
64-bit environments. Fix that in test by using __u64 explicitly, which is
a recommended approach anyway.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-10-andriin@fb.com
Fix btf_dump test cases by hard-coding BPF's pointer size of 8 bytes for cases
where it's impossible to deterimne the pointer size (no long type in BTF). In
cases where it's known, validate libbpf correctly determines it as 8.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-6-andriin@fb.com
With libbpf and BTF it is pretty common to have libbpf built for one
architecture, while BTF information was generated for a different architecture
(typically, but not always, BPF). In such case, the size of a pointer might
differ betweem architectures. libbpf previously was always making an
assumption that pointer size for BTF is the same as native architecture
pointer size, but that breaks for cases where libbpf is built as 32-bit
library, while BTF is for 64-bit architecture.
To solve this, add heuristic to determine pointer size by searching for `long`
or `unsigned long` integer type and using its size as a pointer size. Also,
allow to override the pointer size with a new API btf__set_pointer_size(), for
cases where application knows which pointer size should be used. User
application can check what libbpf "guessed" by looking at the result of
btf__pointer_size(). If it's not 0, then libbpf successfully determined a
pointer size, otherwise native arch pointer size will be used.
For cases where BTF is parsed from ELF file, use ELF's class (32-bit or
64-bit) to determine pointer size.
Fixes: 8a138aed4a ("bpf: btf: Add BTF support to libbpf")
Fixes: 351131b51c ("libbpf: add btf_dump API for BTF-to-C conversion")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-5-andriin@fb.com
Libbpf built in 32-bit mode should be careful about not conflating 64-bit BPF
pointers in BPF ELF file and host architecture pointers. This patch fixes
issue of incorrect initializating of map-in-map inner map slots due to such
difference.
Fixes: 646f02ffdd ("libbpf: Add BTF-defined map-in-map support")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-4-andriin@fb.com