linux-stable.git/tools, branch v5.4.282

selftests/bpf: Fix send_signal test with nested CONFIG_PARAVIRT

2024-08-19T03:33:47+00:00

[ Upstream commit 7015843afcaf68c132784c89528dfddc0005e483 ]

Alexei reported that send_signal test may fail with nested CONFIG_PARAVIRT
configs. In this particular case, the base VM is AMD with 166 cpus, and I
run selftests with regular qemu on top of that and indeed send_signal test
failed. I also tried with an Intel box with 80 cpus and there is no issue.

The main qemu command line includes:

  -enable-kvm -smp 16 -cpu host

The failure log looks like:

  $ ./test_progs -t send_signal
  [   48.501588] watchdog: BUG: soft lockup - CPU#9 stuck for 26s! [test_progs:2225]
  [   48.503622] Modules linked in: bpf_testmod(O)
  [   48.503622] CPU: 9 PID: 2225 Comm: test_progs Tainted: G           O       6.9.0-08561-g2c1713a8f1c9-dirty #69
  [   48.507629] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
  [   48.511635] RIP: 0010:handle_softirqs+0x71/0x290
  [   48.511635] Code: [...] 10 0a 00 00 00 31 c0 65 66 89 05 d5 f4 fa 7e fb bb ff ff ff ff <49> c7 c2 cb
  [   48.518527] RSP: 0018:ffffc90000310fa0 EFLAGS: 00000246
  [   48.519579] RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 00000000000006e0
  [   48.522526] RDX: 0000000000000006 RSI: ffff88810791ae80 RDI: 0000000000000000
  [   48.523587] RBP: ffffc90000fabc88 R08: 00000005a0af4f7f R09: 0000000000000000
  [   48.525525] R10: 0000000561d2f29c R11: 0000000000006534 R12: 0000000000000280
  [   48.528525] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
  [   48.528525] FS:  00007f2f2885cd00(0000) GS:ffff888237c40000(0000) knlGS:0000000000000000
  [   48.531600] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   48.535520] CR2: 00007f2f287059f0 CR3: 0000000106a28002 CR4: 00000000003706f0
  [   48.537538] Call Trace:
  [   48.537538]  
  [   48.537538]  ? watchdog_timer_fn+0x1cd/0x250
  [   48.539590]  ? lockup_detector_update_enable+0x50/0x50
  [   48.539590]  ? __hrtimer_run_queues+0xff/0x280
  [   48.542520]  ? hrtimer_interrupt+0x103/0x230
  [   48.544524]  ? __sysvec_apic_timer_interrupt+0x4f/0x140
  [   48.545522]  ? sysvec_apic_timer_interrupt+0x3a/0x90
  [   48.547612]  ? asm_sysvec_apic_timer_interrupt+0x1a/0x20
  [   48.547612]  ? handle_softirqs+0x71/0x290
  [   48.547612]  irq_exit_rcu+0x63/0x80
  [   48.551585]  sysvec_apic_timer_interrupt+0x75/0x90
  [   48.552521]  
  [   48.553529]  
  [   48.553529]  asm_sysvec_apic_timer_interrupt+0x1a/0x20
  [   48.555609] RIP: 0010:finish_task_switch.isra.0+0x90/0x260
  [   48.556526] Code: [...] 9f 58 0a 00 00 48 85 db 0f 85 89 01 00 00 4c 89 ff e8 53 d9 bd 00 fb 66 90 <4d> 85 ed 74
  [   48.562524] RSP: 0018:ffffc90000fabd38 EFLAGS: 00000282
  [   48.563589] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff83385620
  [   48.563589] RDX: ffff888237c73ae4 RSI: 0000000000000000 RDI: ffff888237c6fd00
  [   48.568521] RBP: ffffc90000fabd68 R08: 0000000000000000 R09: 0000000000000000
  [   48.569528] R10: 0000000000000001 R11: 0000000000000000 R12: ffff8881009d0000
  [   48.573525] R13: ffff8881024e5400 R14: ffff88810791ae80 R15: ffff888237c6fd00
  [   48.575614]  ? finish_task_switch.isra.0+0x8d/0x260
  [   48.576523]  __schedule+0x364/0xac0
  [   48.577535]  schedule+0x2e/0x110
  [   48.578555]  pipe_read+0x301/0x400
  [   48.579589]  ? destroy_sched_domains_rcu+0x30/0x30
  [   48.579589]  vfs_read+0x2b3/0x2f0
  [   48.579589]  ksys_read+0x8b/0xc0
  [   48.583590]  do_syscall_64+0x3d/0xc0
  [   48.583590]  entry_SYSCALL_64_after_hwframe+0x4b/0x53
  [   48.586525] RIP: 0033:0x7f2f28703fa1
  [   48.587592] Code: [...] 00 00 00 0f 1f 44 00 00 f3 0f 1e fa 80 3d c5 23 14 00 00 74 13 31 c0 0f 05 <48> 3d 00 f0
  [   48.593534] RSP: 002b:00007ffd90f8cf88 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
  [   48.595589] RAX: ffffffffffffffda RBX: 00007ffd90f8d5e8 RCX: 00007f2f28703fa1
  [   48.595589] RDX: 0000000000000001 RSI: 00007ffd90f8cfb0 RDI: 0000000000000006
  [   48.599592] RBP: 00007ffd90f8d2f0 R08: 0000000000000064 R09: 0000000000000000
  [   48.602527] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  [   48.603589] R13: 00007ffd90f8d608 R14: 00007f2f288d8000 R15: 0000000000f6bdb0
  [   48.605527]  

In the test, two processes are communicating through pipe. Further debugging
with strace found that the above splat is triggered as read() syscall could
not receive the data even if the corresponding write() syscall in another
process successfully wrote data into the pipe.

The failed subtest is "send_signal_perf". The corresponding perf event has
sample_period 1 and config PERF_COUNT_SW_CPU_CLOCK. sample_period 1 means every
overflow event will trigger a call to the BPF program. So I suspect this may
overwhelm the system. So I increased the sample_period to 100,000 and the test
passed. The sample_period 10,000 still has the test failed.

In other parts of selftest, e.g., [1], sample_freq is used instead. So I
decided to use sample_freq = 1,000 since the test can pass as well.

  [1] https://lore.kernel.org/bpf/20240604070700.3032142-1-song@kernel.org/

Reported-by: Alexei Starovoitov 
Signed-off-by: Yonghong Song 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20240605201203.2603846-1-yonghong.song@linux.dev
Signed-off-by: Sasha Levin

libbpf: Fix no-args func prototype BTF dumping syntax

2024-08-19T03:33:41+00:00

[ Upstream commit 189f1a976e426011e6a5588f1d3ceedf71fe2965 ]

For all these years libbpf's BTF dumper has been emitting not strictly
valid syntax for function prototypes that have no input arguments.

Instead of `int (*blah)()` we should emit `int (*blah)(void)`.

This is not normally a problem, but it manifests when we get kfuncs in
vmlinux.h that have no input arguments. Due to compiler internal
specifics, we get no BTF information for such kfuncs, if they are not
declared with proper `(void)`.

The fix is trivial. We also need to adjust a few ancient tests that
happily assumed `()` is correct.

Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion")
Reported-by: Tejun Heo 
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Stanislav Fomichev 
Link: https://lore.kernel.org/bpf/20240712224442.282823-1-andrii@kernel.org
Signed-off-by: Sasha Levin

selftests/sigaltstack: Fix ppc64 GCC build

2024-08-19T03:33:39+00:00

commit 17c743b9da9e0d073ff19fd5313f521744514939 upstream.

Building the sigaltstack test with GCC on 64-bit powerpc errors with:

  gcc -Wall     sas.c  -o /home/michael/linux/.build/kselftest/sigaltstack/sas
  In file included from sas.c:23:
  current_stack_pointer.h:22:2: error: #error "implement current_stack_pointer equivalent"
     22 | #error "implement current_stack_pointer equivalent"
        |  ^~~~~
  sas.c: In function ‘my_usr1’:
  sas.c:50:13: error: ‘sp’ undeclared (first use in this function); did you mean ‘p’?
     50 |         if (sp < (unsigned long)sstack ||
        |             ^~

This happens because GCC doesn't define __ppc__ for 64-bit builds, only
32-bit builds. Instead use __powerpc__ to detect powerpc builds, which
is defined by clang and GCC for 64-bit and 32-bit builds.

Fixes: 05107edc9101 ("selftests: sigaltstack: fix -Wuninitialized")
Cc: stable@vger.kernel.org # v6.3+
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/20240520062647.688667-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman

tools/memory-model: Fix bug in lock.cat

2024-08-19T03:33:37+00:00

commit 4c830eef806679dc243e191f962c488dd9d00708 upstream.

Andrea reported that the following innocuous litmus test:

C T

{}

P0(spinlock_t *x)
{
	int r0;

	spin_lock(x);
	spin_unlock(x);
	r0 = spin_is_locked(x);
}

gives rise to a nonsensical empty result with no executions:

$ herd7 -conf linux-kernel.cfg T.litmus
Test T Required
States 0
Ok
Witnesses
Positive: 0 Negative: 0
Condition forall (true)
Observation T Never 0 0
Time T 0.00
Hash=6fa204e139ddddf2cb6fa963bad117c0

The problem is caused by a bug in the lock.cat part of the LKMM.  Its
computation of the rf relation for RU (read-unlocked) events is
faulty; it implicitly assumes that every RU event must read from
either a UL (unlock) event in another thread or from the lock's
initial state.  Neither is true in the litmus test above, so the
computation yields no possible executions.

The lock.cat code tries to make up for this deficiency by allowing RU
events outside of critical sections to read from the last po-previous
UL event.  But it does this incorrectly, trying to keep these rfi links
separate from the rfe links that might also be needed, and passing only
the latter to herd7's cross() macro.

The problem is fixed by merging the two sets of possible rf links for
RU events and using them all in the call to cross().

Signed-off-by: Alan Stern 
Reported-by: Andrea Parri 
Closes: https://lore.kernel.org/linux-arch/ZlC0IkzpQdeGj+a3@andrea/
Tested-by: Andrea Parri 
Acked-by: Andrea Parri 
Fixes: 15553dcbca06 ("tools/memory-model: Add model support for spin_is_locked()")
CC: 
Signed-off-by: Paul E. McKenney 
Signed-off-by: Greg Kroah-Hartman

perf report: Fix condition in sort__sym_cmp()

2024-08-19T03:33:31+00:00

[ Upstream commit cb39d05e67dc24985ff9f5150e71040fa4d60ab8 ]

It's expected that both hist entries are in the same hists when
comparing two.  But the current code in the function checks one without
dso sort key and other with the key.  This would make the condition true
in any case.

I guess the intention of the original commit was to add '!' for the
right side too.  But as it should be the same, let's just remove it.

Fixes: 69849fc5d2119 ("perf hists: Move sort__has_dso into struct perf_hpp_list")
Reviewed-by: Kan Liang 
Signed-off-by: Namhyung Kim 
Link: https://lore.kernel.org/r/20240621170528.608772-2-namhyung@kernel.org
Signed-off-by: Sasha Levin

selftests: forwarding: devlink_lib: Wait for udev events after reloading

2024-08-19T03:33:30+00:00

[ Upstream commit f67a90a0c8f5b3d0acc18f10650d90fec44775f9 ]

Lately, an additional locking was added by commit c0a40097f0bc
("drivers: core: synchronize really_probe() and dev_uevent()"). The
locking protects dev_uevent() calling. This function is used to send
messages from the kernel to user space. Uevent messages notify user space
about changes in device states, such as when a device is added, removed,
or changed. These messages are used by udev (or other similar user-space
tools) to apply device-specific rules.

After reloading devlink instance, udev events should be processed. This
locking causes a short delay of udev events handling.

One example for useful udev rule is renaming ports. 'forwading.config'
can be configured to use names after udev rules are applied. Some tests run
devlink_reload() and immediately use the updated names. This worked before
the above mentioned commit was pushed, but now the delay of uevent messages
causes that devlink_reload() returns before udev events are handled and
tests fail.

Adjust devlink_reload() to not assume that udev events are already
processed when devlink reload is done, instead, wait for udev events to
ensure they are processed before returning from the function.

Without this patch:
TESTS='rif_mac_profile' ./resource_scale.sh
TEST: 'rif_mac_profile' 4 [ OK ]
sysctl: cannot stat /proc/sys/net/ipv6/conf/swp1/disable_ipv6: No such file or directory
sysctl: cannot stat /proc/sys/net/ipv6/conf/swp1/disable_ipv6: No such file or directory
sysctl: cannot stat /proc/sys/net/ipv6/conf/swp2/disable_ipv6: No such file or directory
sysctl: cannot stat /proc/sys/net/ipv6/conf/swp2/disable_ipv6: No such file or directory
Cannot find device "swp1"
Cannot find device "swp2"
TEST: setup_wait_dev (: Interface swp1 does not come up.) [FAIL]

With this patch:
$ TESTS='rif_mac_profile' ./resource_scale.sh
TEST: 'rif_mac_profile' 4 [ OK ]
TEST: 'rif_mac_profile' overflow 5 [ OK ]

This is relevant not only for this test.

Fixes: bc7cbb1e9f4c ("selftests: forwarding: Add devlink_lib.sh")
Signed-off-by: Amit Cohen
Reviewed-by: Ido Schimmel
Signed-off-by: Petr Machata
Link: https://patch.msgid.link/89367666e04b38a8993027f1526801ca327ab96a.1720709333.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski
Signed-off-by: Sasha Levin

selftests/bpf: Check length of recv in test_sockmap

2024-08-19T03:33:28+00:00

[ Upstream commit de1b5ea789dc28066cc8dc634b6825bd6148f38b ]

The value of recv in msg_loop may be negative, like EWOULDBLOCK, so it's
necessary to check if it is positive before accumulating it to bytes_recvd.

Fixes: 16962b2404ac ("bpf: sockmap, add selftests")
Signed-off-by: Geliang Tang 
Signed-off-by: Daniel Borkmann 
Tested-by: Jakub Sitnicki 
Acked-by: John Fastabend 
Link: https://lore.kernel.org/bpf/5172563f7c7b2a2e953cef02e89fc34664a7b190.1716446893.git.tanggeliang@kylinos.cn
Signed-off-by: Sasha Levin

selftests/vDSO: fix clang build errors and warnings

2024-07-27T08:38:32+00:00

[ Upstream commit 73810cd45b99c6c418e1c6a487b52c1e74edb20d ]

When building with clang, via:

    make LLVM=1 -C tools/testing/selftests

...there are several warnings, and an error. This fixes all of those and
allows these tests to run and pass.

1. Fix linker error (undefined reference to memcpy) by providing a local
   version of memcpy.

2. clang complains about using this form:

    if (g = h & 0xf0000000)

...so factor out the assignment into a separate step.

3. The code is passing a signed const char* to elf_hash(), which expects
   a const unsigned char *. There are several callers, so fix this at
   the source by allowing the function to accept a signed argument, and
   then converting to unsigned operations, once inside the function.

4. clang doesn't have __attribute__((externally_visible)) and generates
   a warning to that effect. Fortunately, gcc 12 and gcc 13 do not seem
   to require that attribute in order to build, run and pass tests here,
   so remove it.

Reviewed-by: Carlos Llamas 
Reviewed-by: Edward Liaw 
Reviewed-by: Muhammad Usama Anjum 
Tested-by: Muhammad Usama Anjum 
Signed-off-by: John Hubbard 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

selftests: make order checking verbose in msg_zerocopy selftest

2024-07-18T09:40:50+00:00

[ Upstream commit 7d6d8f0c8b700c9493f2839abccb6d29028b4219 ]

We find that when lock debugging is on, notifications may not come in
order. Thus, we have order checking outputs managed by cfg_verbose, to
avoid too many outputs in this case.

Fixes: 07b65c5b31ce ("test: add msg_zerocopy test")
Signed-off-by: Zijian Zhang 
Signed-off-by: Xiaochun Lu 
Reviewed-by: Willem de Bruijn 
Link: https://patch.msgid.link/20240701225349.3395580-3-zijianzhang@bytedance.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

selftests: fix OOM in msg_zerocopy selftest

2024-07-18T09:40:50+00:00

[ Upstream commit af2b7e5b741aaae9ffbba2c660def434e07aa241 ]

In selftests/net/msg_zerocopy.c, it has a while loop keeps calling sendmsg
on a socket with MSG_ZEROCOPY flag, and it will recv the notifications
until the socket is not writable. Typically, it will start the receiving
process after around 30+ sendmsgs. However, as the introduction of commit
dfa2f0483360 ("tcp: get rid of sysctl_tcp_adv_win_scale"), the sender is
always writable and does not get any chance to run recv notifications.
The selftest always exits with OUT_OF_MEMORY because the memory used by
opt_skb exceeds the net.core.optmem_max. Meanwhile, it could be set to a
different value to trigger OOM on older kernels too.

Thus, we introduce "cfg_notification_limit" to force sender to receive
notifications after some number of sendmsgs.

Fixes: 07b65c5b31ce ("test: add msg_zerocopy test")
Signed-off-by: Zijian Zhang 
Signed-off-by: Xiaochun Lu 
Reviewed-by: Willem de Bruijn 
Link: https://patch.msgid.link/20240701225349.3395580-2-zijianzhang@bytedance.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin