[ Upstream commit a0982dfa03 ]
The rcutorture test suite occasionally provokes a splat due to invoking
resched_cpu() on an offline CPU:
WARNING: CPU: 2 PID: 8 at /home/paulmck/public_git/linux-rcu/arch/x86/kernel/smp.c:128 native_smp_send_reschedule+0x37/0x40
Modules linked in:
CPU: 2 PID: 8 Comm: rcu_preempt Not tainted 4.14.0-rc4+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
task: ffff902ede9daf00 task.stack: ffff96c50010c000
RIP: 0010:native_smp_send_reschedule+0x37/0x40
RSP: 0018:ffff96c50010fdb8 EFLAGS: 00010096
RAX: 000000000000002e RBX: ffff902edaab4680 RCX: 0000000000000003
RDX: 0000000080000003 RSI: 0000000000000000 RDI: 00000000ffffffff
RBP: ffff96c50010fdb8 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 00000000299f36ae R12: 0000000000000001
R13: ffffffff9de64240 R14: 0000000000000001 R15: ffffffff9de64240
FS: 0000000000000000(0000) GS:ffff902edfc80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000f7d4c642 CR3: 000000001e0e2000 CR4: 00000000000006e0
Call Trace:
resched_curr+0x8f/0x1c0
resched_cpu+0x2c/0x40
rcu_implicit_dynticks_qs+0x152/0x220
force_qs_rnp+0x147/0x1d0
? sync_rcu_exp_select_cpus+0x450/0x450
rcu_gp_kthread+0x5a9/0x950
kthread+0x142/0x180
? force_qs_rnp+0x1d0/0x1d0
? kthread_create_on_node+0x40/0x40
ret_from_fork+0x27/0x40
Code: 14 01 0f 92 c0 84 c0 74 14 48 8b 05 14 4f f4 00 be fd 00 00 00 ff 90 a0 00 00 00 5d c3 89 fe 48 c7 c7 38 89 ca 9d e8 e5 56 08 00 <0f> ff 5d c3 0f 1f 44 00 00 8b 05 52 9e 37 02 85 c0 75 38 55 48
---[ end trace 26df9e5df4bba4ac ]---
This splat cannot be generated by expedited grace periods because they
always invoke resched_cpu() on the current CPU, which is good because
expedited grace periods require that resched_cpu() unconditionally
succeed. However, other parts of RCU can tolerate resched_cpu() acting
as a no-op, at least as long as it doesn't happen too often.
This commit therefore makes resched_cpu() invoke resched_curr() only if
the CPU is either online or is the current CPU.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2fe2582649 ]
The rcutorture test suite occasionally provokes a splat due to invoking
rt_mutex_lock() which needs to boost the priority of a task currently
sitting on a runqueue that belongs to an offline CPU:
WARNING: CPU: 0 PID: 12 at /home/paulmck/public_git/linux-rcu/arch/x86/kernel/smp.c:128 native_smp_send_reschedule+0x37/0x40
Modules linked in:
CPU: 0 PID: 12 Comm: rcub/7 Not tainted 4.14.0-rc4+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
task: ffff9ed3de5f8cc0 task.stack: ffffbbf80012c000
RIP: 0010:native_smp_send_reschedule+0x37/0x40
RSP: 0018:ffffbbf80012fd10 EFLAGS: 00010082
RAX: 000000000000002f RBX: ffff9ed3dd9cb300 RCX: 0000000000000004
RDX: 0000000080000004 RSI: 0000000000000086 RDI: 00000000ffffffff
RBP: ffffbbf80012fd10 R08: 000000000009da7a R09: 0000000000007b9d
R10: 0000000000000001 R11: ffffffffbb57c2cd R12: 000000000000000d
R13: ffff9ed3de5f8cc0 R14: 0000000000000061 R15: ffff9ed3ded59200
FS: 0000000000000000(0000) GS:ffff9ed3dea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000080686f0 CR3: 000000001b9e0000 CR4: 00000000000006f0
Call Trace:
resched_curr+0x61/0xd0
switched_to_rt+0x8f/0xa0
rt_mutex_setprio+0x25c/0x410
task_blocks_on_rt_mutex+0x1b3/0x1f0
rt_mutex_slowlock+0xa9/0x1e0
rt_mutex_lock+0x29/0x30
rcu_boost_kthread+0x127/0x3c0
kthread+0x104/0x140
? rcu_report_unblock_qs_rnp+0x90/0x90
? kthread_create_on_node+0x40/0x40
ret_from_fork+0x22/0x30
Code: f0 00 0f 92 c0 84 c0 74 14 48 8b 05 34 74 c5 00 be fd 00 00 00 ff 90 a0 00 00 00 5d c3 89 fe 48 c7 c7 a0 c6 fc b9 e8 d5 b5 06 00 <0f> ff 5d c3 0f 1f 44 00 00 8b 05 a2 d1 13 02 85 c0 75 38 55 48
But the target task's priority has already been adjusted, so the only
purpose of switched_to_rt() invoking resched_curr() is to wake up the
CPU running some task that needs to be preempted by the boosted task.
But the CPU is offline, which presumably means that the task must be
migrated to some other CPU, and that this other CPU will undertake any
needed preemption at the time of migration. Because the runqueue lock
is held when resched_curr() is invoked, we know that the boosted task
cannot go anywhere, so it is not necessary to invoke resched_curr()
in this particular case.
This commit therefore makes switched_to_rt() refrain from invoking
resched_curr() when the target CPU is offline.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ upstream commit ca36960211 ]
The requirements around atomic_add() / atomic64_add() resp. their
JIT implementations differ across architectures. E.g. while x86_64
seems just fine with BPF's xadd on unaligned memory, on arm64 it
triggers via interpreter but also JIT the following crash:
[ 830.864985] Unable to handle kernel paging request at virtual address ffff8097d7ed6703
[...]
[ 830.916161] Internal error: Oops: 96000021 [#1] SMP
[ 830.984755] CPU: 37 PID: 2788 Comm: test_verifier Not tainted 4.16.0-rc2+ #8
[ 830.991790] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.29 07/17/2017
[ 830.998998] pstate: 80400005 (Nzcv daif +PAN -UAO)
[ 831.003793] pc : __ll_sc_atomic_add+0x4/0x18
[ 831.008055] lr : ___bpf_prog_run+0x1198/0x1588
[ 831.012485] sp : ffff00001ccabc20
[ 831.015786] x29: ffff00001ccabc20 x28: ffff8017d56a0f00
[ 831.021087] x27: 0000000000000001 x26: 0000000000000000
[ 831.026387] x25: 000000c168d9db98 x24: 0000000000000000
[ 831.031686] x23: ffff000008203878 x22: ffff000009488000
[ 831.036986] x21: ffff000008b14e28 x20: ffff00001ccabcb0
[ 831.042286] x19: ffff0000097b5080 x18: 0000000000000a03
[ 831.047585] x17: 0000000000000000 x16: 0000000000000000
[ 831.052885] x15: 0000ffffaeca8000 x14: 0000000000000000
[ 831.058184] x13: 0000000000000000 x12: 0000000000000000
[ 831.063484] x11: 0000000000000001 x10: 0000000000000000
[ 831.068783] x9 : 0000000000000000 x8 : 0000000000000000
[ 831.074083] x7 : 0000000000000000 x6 : 000580d428000000
[ 831.079383] x5 : 0000000000000018 x4 : 0000000000000000
[ 831.084682] x3 : ffff00001ccabcb0 x2 : 0000000000000001
[ 831.089982] x1 : ffff8097d7ed6703 x0 : 0000000000000001
[ 831.095282] Process test_verifier (pid: 2788, stack limit = 0x0000000018370044)
[ 831.102577] Call trace:
[ 831.105012] __ll_sc_atomic_add+0x4/0x18
[ 831.108923] __bpf_prog_run32+0x4c/0x70
[ 831.112748] bpf_test_run+0x78/0xf8
[ 831.116224] bpf_prog_test_run_xdp+0xb4/0x120
[ 831.120567] SyS_bpf+0x77c/0x1110
[ 831.123873] el0_svc_naked+0x30/0x34
[ 831.127437] Code: 97fffe97 17ffffec 00000000 f9800031 (885f7c31)
Reason for this is because memory is required to be aligned. In
case of BPF, we always enforce alignment in terms of stack access,
but not when accessing map values or packet data when the underlying
arch (e.g. arm64) has CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS set.
xadd on packet data that is local to us anyway is just wrong, so
forbid this case entirely. The only place where xadd makes sense in
fact are map values; xadd on stack is wrong as well, but it's been
around for much longer. Specifically enforce strict alignment in case
of xadd, so that we handle this case generically and avoid such crashes
in the first place.
Fixes: 17a5267067 ("bpf: verifier (add verifier core)")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ upstream commit 32fff239de ]
syszbot managed to trigger RCU detected stalls in
bpf_array_free_percpu()
It takes time to allocate a huge percpu map, but even more time to free
it.
Since we run in process context, use cond_resched() to yield cpu if
needed.
Fixes: a10423b87a ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ upstream commit 6c5f61023c ]
Commit 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
fixed a memory leak and removed unnecessary locks in map_free callback function.
Unfortrunately, it introduced a lockdep warning. When lockdep checking is turned on,
running tools/testing/selftests/bpf/test_lpm_map will have:
[ 98.294321] =============================
[ 98.294807] WARNING: suspicious RCU usage
[ 98.295359] 4.16.0-rc2+ #193 Not tainted
[ 98.295907] -----------------------------
[ 98.296486] /home/yhs/work/bpf/kernel/bpf/lpm_trie.c:572 suspicious rcu_dereference_check() usage!
[ 98.297657]
[ 98.297657] other info that might help us debug this:
[ 98.297657]
[ 98.298663]
[ 98.298663] rcu_scheduler_active = 2, debug_locks = 1
[ 98.299536] 2 locks held by kworker/2:1/54:
[ 98.300152] #0: ((wq_completion)"events"){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0
[ 98.301381] #1: ((work_completion)(&map->work)){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0
Since actual trie tree removal happens only after no other
accesses to the tree are possible, replacing
rcu_dereference_protected(*slot, lockdep_is_held(&trie->lock))
with
rcu_dereference_protected(*slot, 1)
fixed the issue.
Fixes: 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
Reported-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ upstream commit 9a3efb6b66 ]
There is a memory leak happening in lpm_trie map_free callback
function trie_free. The trie structure itself does not get freed.
Also, trie_free function did not do synchronize_rcu before freeing
various data structures. This is incorrect as some rcu_read_lock
region(s) for lookup, update, delete or get_next_key may not complete yet.
The fix is to add synchronize_rcu in the beginning of trie_free.
The useless spin_lock is removed from this function as well.
Fixes: b95a5c4db0 ("bpf: add a longest prefix match trie map implementation")
Reported-by: Mathieu Malaterre <malat@debian.org>
Reported-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ upstream commit 9c2d63b843 ]
syzkaller recently triggered OOM during percpu map allocation;
while there is work in progress by Dennis Zhou to add __GFP_NORETRY
semantics for percpu allocator under pressure, there seems also a
missing bpf_map_precharge_memlock() check in array map allocation.
Given today the actual bpf_map_charge_memlock() happens after the
find_and_alloc_map() in syscall path, the bpf_map_precharge_memlock()
is there to bail out early before we go and do the map setup work
when we find that we hit the limits anyway. Therefore add this for
array map as well.
Fixes: 6c90598174 ("bpf: pre-allocate hash map elements")
Fixes: a10423b87a ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map")
Reported-by: syzbot+adb03f3f0bb57ce3acda@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Dennis Zhou <dennisszhou@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c52232a49e upstream.
On CPU hotunplug the enqueued timers of the unplugged CPU are migrated to a
live CPU. This happens from the control thread which initiated the unplug.
If the CPU on which the control thread runs came out from a longer idle
period then the base clock of that CPU might be stale because the control
thread runs prior to any event which forwards the clock.
In such a case the timers from the unplugged CPU are queued on the live CPU
based on the stale clock which can cause large delays due to increased
granularity of the outer timer wheels which are far away from base:;clock.
But there is a worse problem than that. The following sequence of events
illustrates it:
- CPU0 timer1 is queued expires = 59969 and base->clk = 59131.
The timer is queued at wheel level 2, with resulting expiry time = 60032
(due to level granularity).
- CPU1 enters idle @60007, with next timer expiry @60020.
- CPU0 is hotplugged at @60009
- CPU1 exits idle and runs the control thread which migrates the
timers from CPU0
timer1 is now queued in level 0 for immediate handling in the next
softirq because the requested expiry time 59969 is before CPU1 base->clk
60007
- CPU1 runs code which forwards the base clock which succeeds because the
next expiring timer. which was collected at idle entry time is still set
to 60020.
So it forwards beyond 60007 and therefore misses to expire the migrated
timer1. That timer gets expired when the wheel wraps around again, which
takes between 63 and 630ms depending on the HZ setting.
Address both problems by invoking forward_timer_base() for the control CPUs
timer base. All other places, which might run into a similar problem
(mod_timer()/add_timer_on()) already invoke forward_timer_base() to avoid
that.
[ tglx: Massaged comment and changelog ]
Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Co-developed-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: linux-arm-msm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180118115022.6368-1-clingutla@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 651ca2c004 upstream.
At CPU hotunplug the corresponding per cpu matrix allocator is shut down and
the allocated interrupt bits are discarded under the assumption that all
allocated bits have been either migrated away or shut down through the
managed interrupts mechanism.
This is not true because interrupts which are not started up might have a
vector allocated on the outgoing CPU. When the interrupt is started up
later or completely shutdown and freed then the allocated vector is handed
back, triggering warnings or causing accounting issues which result in
suspend failures and other issues.
Change the CPU hotplug mechanism of the matrix allocator so that the
remaining allocations at unplug time are preserved and global accounting at
hotplug is correctly readjusted to take the dormant vectors into account.
Fixes: 2f75d9e1c9 ("genirq: Implement bitmap matrix allocator")
Reported-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180222112316.849980972@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0723402141 upstream.
Al Viro reported:
For substring - sure, but what about something like "*a*b" and "a*b"?
AFAICS, filter_parse_regex() ends up with identical results in both
cases - MATCH_GLOB and *search = "a*b". And no way for the caller
to tell one from another.
Testing this with the following:
# cd /sys/kernel/tracing
# echo '*raw*lock' > set_ftrace_filter
bash: echo: write error: Invalid argument
With this patch:
# echo '*raw*lock' > set_ftrace_filter
# cat set_ftrace_filter
_raw_read_trylock
_raw_write_trylock
_raw_read_unlock
_raw_spin_unlock
_raw_write_unlock
_raw_spin_trylock
_raw_spin_lock
_raw_write_lock
_raw_read_lock
Al recommended not setting the search buffer to skip the first '*' unless we
know we are not using MATCH_GLOB. This implements his suggested logic.
Link: http://lkml.kernel.org/r/20180127170748.GF13338@ZenIV.linux.org.uk
Cc: stable@vger.kernel.org
Fixes: 60f1d5e3ba ("ftrace: Support full glob matching")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Suggsted-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 10a0cd6e49 upstream.
The functions devm_memremap_pages() and devm_memremap_pages_release() use
different ways to calculate the section-aligned amount of memory. The
latter function may use an incorrect size if the memory region is small
but straddles a section border.
Use the same code for both.
Cc: <stable@vger.kernel.org>
Fixes: 5f29a77cd9 ("mm: fix mixed zone detection in devm_memremap_pages")
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0e4d819d08 upstream.
Recently, how the pointers being printed with %p has been changed
by commit ad67b74d24 ("printk: hash addresses printed with %p").
This is causing a regression while showing offset in the
uprobe_events file. Instead of %p, use %px to display offset.
Before patch:
# perf probe -vv -x /tmp/a.out main
Opening /sys/kernel/debug/tracing//uprobe_events write=1
Writing event: p:probe_a/main /tmp/a.out:0x58c
# cat /sys/kernel/debug/tracing/uprobe_events
p:probe_a/main /tmp/a.out:0x0000000049a0f352
After patch:
# cat /sys/kernel/debug/tracing/uprobe_events
p:probe_a/main /tmp/a.out:0x000000000000058c
Link: http://lkml.kernel.org/r/20180106054246.15375-1-ravi.bangoria@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 156baec397 upstream.
Use of init_rcu_head() and destroy_rcu_head() from modules results in
the following build-time error with CONFIG_DEBUG_OBJECTS_RCU_HEAD=y:
ERROR: "init_rcu_head" [drivers/scsi/scsi_mod.ko] undefined!
ERROR: "destroy_rcu_head" [drivers/scsi/scsi_mod.ko] undefined!
This commit therefore adds EXPORT_SYMBOL_GPL() for each to allow them to
be used by GPL-licensed kernel modules.
Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7b65865627 upstream.
__unregister_ftrace_function_probe() will incorrectly parse the glob filter
because it resets the search variable that was setup by filter_parse_regex().
Al Viro reported this:
After that call of filter_parse_regex() we could have func_g.search not
equal to glob only if glob started with '!' or '*'. In the former case
we would've buggered off with -EINVAL (not = 1). In the latter we
would've set func_g.search equal to glob + 1, calculated the length of
that thing in func_g.len and proceeded to reset func_g.search back to
glob.
Suppose the glob is e.g. *foo*. We end up with
func_g.type = MATCH_MIDDLE_ONLY;
func_g.len = 3;
func_g.search = "*foo";
Feeding that to ftrace_match_record() will not do anything sane - we
will be looking for names containing "*foo" (->len is ignored for that
one).
Link: http://lkml.kernel.org/r/20180127031706.GE13338@ZenIV.linux.org.uk
Fixes: 3ba0092971 ("ftrace: Introduce ftrace_glob structure")
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1beaeacdc8 upstream.
Meelis reported the following warning on a quad P3 HP NetServer museum piece:
WARNING: CPU: 3 PID: 258 at kernel/irq/chip.c:244 __irq_startup+0x80/0x100
EIP: __irq_startup+0x80/0x100
irq_startup+0x7e/0x170
probe_irq_on+0x128/0x2b0
parport_irq_probe.constprop.18+0x8d/0x1af [parport_pc]
parport_pc_probe_port+0xf11/0x1260 [parport_pc]
parport_pc_init+0x78a/0xf10 [parport_pc]
parport_parse_param.constprop.16+0xf0/0xf0 [parport_pc]
do_one_initcall+0x45/0x1e0
This is caused by the rewrite of the irq activation/startup sequence which
missed to convert a callsite in the irq legacy auto probing code.
To fix this irq_activate_and_startup() needs to gain a return value so the
pending logic can work proper.
Fixes: c942cee46b ("genirq: Separate activation and startup")
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Meelis Roos <mroos@linux.ee>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801301935410.1797@nanos
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4f7e988e63 upstream.
This reverts commit 92266d6ef6 ("async: simplify lowest_in_progress()")
which was simply wrong: In the case where domain is NULL, we now use the
wrong offsetof() in the list_first_entry macro, so we don't actually
fetch the ->cookie value, but rather the eight bytes located
sizeof(struct list_head) further into the struct async_entry.
On 64 bit, that's the data member, while on 32 bit, that's a u64 built
from func and data in some order.
I think the bug happens to be harmless in practice: It obviously only
affects callers which pass a NULL domain, and AFAICT the only such
caller is
async_synchronize_full() ->
async_synchronize_full_domain(NULL) ->
async_synchronize_cookie_domain(ASYNC_COOKIE_MAX, NULL)
and the ASYNC_COOKIE_MAX means that in practice we end up waiting for
the async_global_pending list to be empty - but it would break if
somebody happened to pass (void*)-1 as the data element to
async_schedule, and of course also if somebody ever does a
async_synchronize_cookie_domain(, NULL) with a "finite" cookie value.
Maybe the "harmless in practice" means this isn't -stable material. But
I'm not completely confident my quick git grep'ing is enough, and there
might be affected code in one of the earlier kernels that has since been
removed, so I'll leave the decision to the stable guys.
Link: http://lkml.kernel.org/r/20171128104938.3921-1-linux@rasmusvillemoes.dk
Fixes: 92266d6ef6 "async: simplify lowest_in_progress()"
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Adam Wallis <awallis@codeaurora.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 364f566537 upstream.
When issuing an IPI RT push, where an IPI is sent to each CPU that has more
than one RT task scheduled on it, it references the root domain's rto_mask,
that contains all the CPUs within the root domain that has more than one RT
task in the runable state. The problem is, after the IPIs are initiated, the
rq->lock is released. This means that the root domain that is associated to
the run queue could be freed while the IPIs are going around.
Add a sched_get_rd() and a sched_put_rd() that will increment and decrement
the root domain's ref count respectively. This way when initiating the IPIs,
the scheduler will up the root domain's ref count before releasing the
rq->lock, ensuring that the root domain does not go away until the IPI round
is complete.
Reported-by: Pavan Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 4bdced5c9a ("sched/rt: Simplify the IPI based RT balancing logic")
Link: http://lkml.kernel.org/r/CAEU1=PkiHO35Dzna8EQqNSKW1fr1y1zRQ5y66X117MG06sQtNA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ad0f1d9d65 upstream.
When the rto_push_irq_work_func() is called, it looks at the RT overloaded
bitmask in the root domain via the runqueue (rq->rd). The problem is that
during CPU up and down, nothing here stops rq->rd from changing between
taking the rq->rd->rto_lock and releasing it. That means the lock that is
released is not the same lock that was taken.
Instead of using this_rq()->rd to get the root domain, as the irq work is
part of the root domain, we can simply get the root domain from the irq work
that is passed to the routine:
container_of(work, struct root_domain, rto_push_work)
This keeps the root domain consistent.
Reported-by: Pavan Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 4bdced5c9a ("sched/rt: Simplify the IPI based RT balancing logic")
Link: http://lkml.kernel.org/r/CAEU1=PkiHO35Dzna8EQqNSKW1fr1y1zRQ5y66X117MG06sQtNA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit caf7501a1b
There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.
To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.
If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.
[ tglx: Massaged changelog ]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull timer fix from Thomas Gleixner:
"A single fix for a ~10 years old problem which causes high resolution
timers to stop after a CPU unplug/plug cycle due to a stale flag in
the per CPU hrtimer base struct.
Paul McKenney was hunting this for about a year, but the heisenbug
nature made it resistant against debug attempts for quite some time"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimer: Reset hrtimer cpu base proper on CPU hotplug
Pull scheduler fix from Thomas Gleixner:
"A single bug fix to prevent a subtle deadlock in the scheduler core
code vs cpu hotplug"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Fix cpu.max vs. cpuhotplug deadlock
Pull perf fixes from Thomas Gleixner:
"Four patches which all address lock inversions and deadlocks in the
perf core code and the Intel debug store"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Fix perf,x86,cpuhp deadlock
perf/core: Fix ctx::mutex deadlock
perf/core: Fix another perf,trace,cpuhp lock inversion
perf/core: Fix lock inversion between perf,trace,cpuhp
Pull locking fixes from Thomas Gleixner:
"Two final locking fixes for 4.15:
- Repair the OWNER_DIED logic in the futex code which got wreckaged
with the recent fix for a subtle race condition.
- Prevent the hard lockup detector from triggering when dumping all
held locks in the system"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Avoid triggering hardlockup from debug_show_all_locks()
futex: Fix OWNER_DEAD fixup
The hrtimer interrupt code contains a hang detection and mitigation
mechanism, which prevents that a long delayed hrtimer interrupt causes a
continous retriggering of interrupts which prevent the system from making
progress. If a hang is detected then the timer hardware is programmed with
a certain delay into the future and a flag is set in the hrtimer cpu base
which prevents newly enqueued timers from reprogramming the timer hardware
prior to the chosen delay. The subsequent hrtimer interrupt after the delay
clears the flag and resumes normal operation.
If such a hang happens in the last hrtimer interrupt before a CPU is
unplugged then the hang_detected flag is set and stays that way when the
CPU is plugged in again. At that point the timer hardware is not armed and
it cannot be armed because the hang_detected flag is still active, so
nothing clears that flag. As a consequence the CPU does not receive hrtimer
interrupts and no timers expire on that CPU which results in RCU stalls and
other malfunctions.
Clear the flag along with some other less critical members of the hrtimer
cpu base to ensure starting from a clean state when a CPU is plugged in.
Thanks to Paul, Sebastian and Anna-Maria for their help to get down to the
root cause of that hard to reproduce heisenbug. Once understood it's
trivial and certainly justifies a brown paperbag.
Fixes: 41d2e49493 ("hrtimer: Tune hrtimer_interrupt hang logic")
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Sewior <bigeasy@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801261447590.2067@nanos
Lockdep noticed the following 3-way lockup scenario:
sys_perf_event_open()
perf_event_alloc()
perf_try_init_event()
#0 ctx = perf_event_ctx_lock_nested(1)
perf_swevent_init()
swevent_hlist_get()
#1 mutex_lock(&pmus_lock)
perf_event_init_cpu()
#1 mutex_lock(&pmus_lock)
#2 mutex_lock(&ctx->mutex)
sys_perf_event_open()
mutex_lock_double()
#2 mutex_lock()
#0 mutex_lock_nested()
And while we need that perf_event_ctx_lock_nested() for HW PMUs such
that they can iterate the sibling list, trying to match it to the
available counters, the software PMUs need do no such thing. Exclude
them.
In particular the swevent triggers the above invertion, while the
tpevent PMU triggers a more elaborate one through their event_mutex.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
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: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Lockdep noticed the following 3-way lockup race:
perf_trace_init()
#0 mutex_lock(&event_mutex)
perf_trace_event_init()
perf_trace_event_reg()
tp_event->class->reg() := tracepoint_probe_register
#1 mutex_lock(&tracepoints_mutex)
trace_point_add_func()
#2 static_key_enable()
#2 do_cpu_up()
perf_event_init_cpu()
#3 mutex_lock(&pmus_lock)
#4 mutex_lock(&ctx->mutex)
perf_ioctl()
#4 ctx = perf_event_ctx_lock()
_perf_iotcl()
ftrace_profile_set_filter()
#0 mutex_lock(&event_mutex)
Fudge it for now by noting that the tracepoint state does not depend
on the event <-> context relation. Ugly though :/
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With the addition of ORC unwinder and FRAME POINTER unwinder, the stack
trace skipping requirements have changed.
I went through the tracing stack trace dumps with ORC and with frame
pointers and recalculated the proper values.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The function tracer can create a dynamically allocated trampoline that is
called by the function mcount or fentry hook that is used to call the
function callback that is registered. The problem is that the orc undwinder
will bail if it encounters one of these trampolines. This breaks the stack
trace of function callbacks, which include the stack tracer and setting the
stack trace for individual functions.
Since these dynamic trampolines are basically copies of the static ftrace
trampolines defined in ftrace_*.S, we do not need to create new orc entries
for the dynamic trampolines. Finding the return address on the stack will be
identical as the functions that were copied to create the dynamic
trampolines. When encountering a ftrace dynamic trampoline, we can just use
the orc entry of the ftrace static function that was copied for that
trampoline.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull irq fix from Thomas Gleixner:
"A single fix for the new matrix allocator to prevent vector exhaustion
by certain network drivers which allocate gazillions of unused vectors
which cannot be put into reservation mode due to MSI and the lack of
MSI entry masking.
The fix/workaround is to spread the vectors across CPUs by searching
the supplied target CPU mask for the CPU with the smallest number of
allocated vectors"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq/matrix: Spread interrupts on allocation
Pull tracing fixes from Steven Rostedt:
"Two more small fixes
- The conversion of enums into their actual numbers to display in the
event format file had an off-by-one bug, that could cause an enum
not to be converted, and break user space parsing tools.
- A fix to a previous fix to bring back the context recursion checks.
The interrupt case checks for NMI, IRQ and softirq, but the softirq
returned the same number regardless if it was set or not, although
the logic would force it to be set if it were hit"
* tag 'trace-v4.15-rc4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix converting enum's from the map in trace_event_eval_update()
ring-buffer: Fix duplicate results in mapping context to bits in recursive lock
Pull cgroup fix from Tejun Heo:
"cgroup.threads should be delegatable (ie. a container should be able
to write to it from inside) but was missing the flag.
The change is very low risk"
* 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: make cgroup.threads delegatable
Pull workqueue fixlet from Tejun Heo:
"One patch to add touch_nmi_watchdog() while dumping workqueue debug
messages to avoid triggering the lockup detector spuriously.
The change is very low risk"
* 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: avoid hard lockups in show_workqueue_state()
Pull networking fixes from David Miller:
1) Fix BPF divides by zero, from Eric Dumazet and Alexei Starovoitov.
2) Reject stores into bpf context via st and xadd, from Daniel
Borkmann.
3) Fix a memory leak in TUN, from Cong Wang.
4) Disable RX aggregation on a specific troublesome configuration of
r8152 in a Dell TB16b dock.
5) Fix sw_ctx leak in tls, from Sabrina Dubroca.
6) Fix program replacement in cls_bpf, from Daniel Borkmann.
7) Fix uninitialized station_info structures in cfg80211, from Johannes
Berg.
8) Fix miscalculation of transport header offset field in flow
dissector, from Eric Dumazet.
9) Fix LPM tree leak on failure in mlxsw driver, from Ido Schimmel.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (29 commits)
ibmvnic: Fix IPv6 packet descriptors
ibmvnic: Fix IP offload control buffer
ipv6: don't let tb6_root node share routes with other node
ip6_gre: init dev->mtu and dev->hard_header_len correctly
mlxsw: spectrum_router: Free LPM tree upon failure
flow_dissector: properly cap thoff field
fm10k: mark PM functions as __maybe_unused
cfg80211: fix station info handling bugs
netlink: reset extack earlier in netlink_rcv_skb
can: af_can: canfd_rcv(): replace WARN_ONCE by pr_warn_once
can: af_can: can_rcv(): replace WARN_ONCE by pr_warn_once
bpf: mark dst unknown on inconsistent {s, u}bounds adjustments
bpf: fix cls_bpf on filter replace
Net: ethernet: ti: netcp: Fix inbound ping crash if MTU size is greater than 1500
tls: reset crypto_info when do_tls_setsockopt_tx fails
tls: return -EBUSY if crypto_info is already set
tls: fix sw_ctx leak
net/tls: Only attach to sockets in ESTABLISHED state
net: fs_enet: do not call phy_stop() in interrupts
r8152: disable RX aggregation on Dell TB16 dock
...
Since enums do not get converted by the TRACE_EVENT macro into their values,
the event format displaces the enum name and not the value. This breaks
tools like perf and trace-cmd that need to interpret the raw binary data. To
solve this, an enum map was created to convert these enums into their actual
numbers on boot up. This is done by TRACE_EVENTS() adding a
TRACE_DEFINE_ENUM() macro.
Some enums were not being converted. This was caused by an optization that
had a bug in it.
All calls get checked against this enum map to see if it should be converted
or not, and it compares the call's system to the system that the enum map
was created under. If they match, then they call is processed.
To cut down on the number of iterations needed to find the maps with a
matching system, since calls and maps are grouped by system, when a match is
made, the index into the map array is saved, so that the next call, if it
belongs to the same system as the previous call, could start right at that
array index and not have to scan all the previous arrays.
The problem was, the saved index was used as the variable to know if this is
a call in a new system or not. If the index was zero, it was assumed that
the call is in a new system and would keep incrementing the saved index
until it found a matching system. The issue arises when the first matching
system was at index zero. The next map, if it belonged to the same system,
would then think it was the first match and increment the index to one. If
the next call belong to the same system, it would begin its search of the
maps off by one, and miss the first enum that should be converted. This left
a single enum not converted properly.
Also add a comment to describe exactly what that index was for. It took me a
bit too long to figure out what I was thinking when debugging this issue.
Link: http://lkml.kernel.org/r/717BE572-2070-4C1E-9902-9F2E0FEDA4F8@oracle.com
Cc: stable@vger.kernel.org
Fixes: 0c564a538a ("tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values")
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Teste-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In bringing back the context checks, the code checks first if its normal
(non-interrupt) context, and then for NMI then IRQ then softirq. The final
check is redundant. Since the if branch is only hit if the context is one of
NMI, IRQ, or SOFTIRQ, if it's not NMI or IRQ there's no reason to check if
it is SOFTIRQ. The current code returns the same result even if its not a
SOFTIRQ. Which is confusing.
pc & SOFTIRQ_OFFSET ? 2 : RB_CTX_SOFTIRQ
Is redundant as RB_CTX_SOFTIRQ *is* 2!
Fixes: a0e3a18f4b ("ring-buffer: Bring back context level recursive checks")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
pull-request: bpf 2018-01-18
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix a divide by zero due to wrong if (src_reg == 0) check in
64-bit mode. Properly handle this in interpreter and mask it
also generically in verifier to guard against similar checks
in JITs, from Eric and Alexei.
2) Fix a bug in arm64 JIT when tail calls are involved and progs
have different stack sizes, from Daniel.
3) Reject stores into BPF context that are not expected BPF_STX |
BPF_MEM variant, from Daniel.
4) Mark dst reg as unknown on {s,u}bounds adjustments when the
src reg has derived bounds from dead branches, from Daniel.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Keith reported an issue with vector space exhaustion on a server machine
which is caused by the i40e driver allocating 168 MSI interrupts when the
driver is initialized, even when most of these interrupts are not used at
all.
The x86 vector allocation code tries to avoid the immediate allocation with
the reservation mode, but the card uses MSI and does not support MSI entry
masking, which prevents reservation mode and requires immediate vector
allocation.
The matrix allocator is a bit naive and prefers the first CPU in the
cpumask which describes the possible target CPUs for an allocation. That
results in allocating all 168 vectors on CPU0 which later causes vector
space exhaustion when the NVMe driver tries to allocate managed interrupts
on each CPU for the per CPU queues.
Avoid this by finding the CPU which has the lowest vector allocation count
to spread out the non managed interrupt accross the possible target CPUs.
Fixes: 2f75d9e1c9 ("genirq: Implement bitmap matrix allocator")
Reported-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Keith Busch <keith.busch@intel.com>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801171557330.1777@nanos
syzkaller generated a BPF proglet and triggered a warning with
the following:
0: (b7) r0 = 0
1: (d5) if r0 s<= 0x0 goto pc+0
R0=inv0 R1=ctx(id=0,off=0,imm=0) R10=fp0
2: (1f) r0 -= r1
R0=inv0 R1=ctx(id=0,off=0,imm=0) R10=fp0
verifier internal error: known but bad sbounds
What happens is that in the first insn, r0's min/max value
are both 0 due to the immediate assignment, later in the jsle
test the bounds are updated for the min value in the false
path, meaning, they yield smin_val = 1, smax_val = 0, and when
ctx pointer is subtracted from r0, verifier bails out with the
internal error and throwing a WARN since smin_val != smax_val
for the known constant.
For min_val > max_val scenario it means that reg_set_min_max()
and reg_set_min_max_inv() (which both refine existing bounds)
demonstrated that such branch cannot be taken at runtime.
In above scenario for the case where it will be taken, the
existing [0, 0] bounds are kept intact. Meaning, the rejection
is not due to a verifier internal error, and therefore the
WARN() is not necessary either.
We could just reject such cases in adjust_{ptr,scalar}_min_max_vals()
when either known scalars have smin_val != smax_val or
umin_val != umax_val or any scalar reg with bounds
smin_val > smax_val or umin_val > umax_val. However, there
may be a small risk of breakage of buggy programs, so handle
this more gracefully and in adjust_{ptr,scalar}_min_max_vals()
just taint the dst reg as unknown scalar when we see ops with
such kind of src reg.
Reported-by: syzbot+6d362cadd45dc0a12ba4@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
