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2018-10-16locking/qspinlock, x86: Provide liveness guaranteePeter Zijlstra
On x86 we cannot do fetch_or() with a single instruction and thus end up using a cmpxchg loop, this reduces determinism. Replace the fetch_or() with a composite operation: tas-pending + load. Using two instructions of course opens a window we previously did not have. Consider the scenario: CPU0 CPU1 CPU2 1) lock trylock -> (0,0,1) 2) lock trylock /* fail */ 3) unlock -> (0,0,0) 4) lock trylock -> (0,0,1) 5) tas-pending -> (0,1,1) load-val <- (0,1,0) from 3 6) clear-pending-set-locked -> (0,0,1) FAIL: _2_ owners where 5) is our new composite operation. When we consider each part of the qspinlock state as a separate variable (as we can when _Q_PENDING_BITS == 8) then the above is entirely possible, because tas-pending will only RmW the pending byte, so the later load is able to observe prior tail and lock state (but not earlier than its own trylock, which operates on the whole word, due to coherence). To avoid this we need 2 things: - the load must come after the tas-pending (obviously, otherwise it can trivially observe prior state). - the tas-pending must be a full word RmW instruction, it cannot be an XCHGB for example, such that we cannot observe other state prior to setting pending. On x86 we can realize this by using "LOCK BTS m32, r32" for tas-pending followed by a regular load. Note that observing later state is not a problem: - if we fail to observe a later unlock, we'll simply spin-wait for that store to become visible. - if we observe a later xchg_tail(), there is no difference from that xchg_tail() having taken place before the tas-pending. Suggested-by: Will Deacon <will.deacon@arm.com> Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: andrea.parri@amarulasolutions.com Cc: longman@redhat.com Fixes: 59fb586b4a07 ("locking/qspinlock: Remove unbounded cmpxchg() loop from locking slowpath") Link: https://lkml.kernel.org/r/20181003130957.183726335@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16locking/qspinlock: Rework some commentsPeter Zijlstra
While working my way through the code again; I felt the comments could use help. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: andrea.parri@amarulasolutions.com Cc: longman@redhat.com Link: https://lkml.kernel.org/r/20181003130257.156322446@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16locking/qspinlock: Re-order codePeter Zijlstra
Flip the branch condition after atomic_fetch_or_acquire(_Q_PENDING_VAL) such that we loose the indent. This also result in a more natural code flow IMO. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: andrea.parri@amarulasolutions.com Cc: longman@redhat.com Link: https://lkml.kernel.org/r/20181003130257.156322446@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16Merge branch 'x86/build' into locking/core, to pick up dependent patches and ↵Ingo Molnar
unify jump-label work Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16sched/fair: Fix the min_vruntime update logic in dequeue_entity()Song Muchun
The comment and the code around the update_min_vruntime() call in dequeue_entity() are not in agreement. From commit: b60205c7c558 ("sched/fair: Fix min_vruntime tracking") I think that we want to update min_vruntime when a task is sleeping/migrating. So, the check is inverted there - fix it. Signed-off-by: Song Muchun <smuchun@gmail.com> 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: b60205c7c558 ("sched/fair: Fix min_vruntime tracking") Link: http://lkml.kernel.org/r/20181014112612.2614-1-smuchun@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16locking/lockdep: Remove duplicated 'lock_class_ops' percpu arrayWaiman Long
Remove the duplicated 'lock_class_ops' percpu array that is not used anywhere. Signed-off-by: Waiman Long <longman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Fixes: 8ca2b56cd7da ("locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y") Link: http://lkml.kernel.org/r/1539380547-16726-1-git-send-email-longman@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf-next 2018-10-16 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Convert BPF sockmap and kTLS to both use a new sk_msg API and enable sk_msg BPF integration for the latter, from Daniel and John. 2) Enable BPF syscall side to indicate for maps that they do not support a map lookup operation as opposed to just missing key, from Prashant. 3) Add bpftool map create command which after map creation pins the map into bpf fs for further processing, from Jakub. 4) Add bpftool support for attaching programs to maps allowing sock_map and sock_hash to be used from bpftool, from John. 5) Improve syscall BPF map update/delete path for map-in-map types to wait a RCU grace period for pending references to complete, from Daniel. 6) Couple of follow-up fixes for the BPF socket lookup to get it enabled also when IPv6 is compiled as a module, from Joe. 7) Fix a generic-XDP bug to handle the case when the Ethernet header was mangled and thus update skb's protocol and data, from Jesper. 8) Add a missing BTF header length check between header copies from user space, from Wenwen. 9) Minor fixups in libbpf to use __u32 instead u32 types and include proper perf_event.h uapi header instead of perf internal one, from Yonghong. 10) Allow to pass user-defined flags through EXTRA_CFLAGS and EXTRA_LDFLAGS to bpftool's build, from Jiri. 11) BPF kselftest tweaks to add LWTUNNEL to config fragment and to install with_addr.sh script from flow dissector selftest, from Anders. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15bpf, sockmap: convert to generic sk_msg interfaceDaniel Borkmann
Add a generic sk_msg layer, and convert current sockmap and later kTLS over to make use of it. While sk_buff handles network packet representation from netdevice up to socket, sk_msg handles data representation from application to socket layer. This means that sk_msg framework spans across ULP users in the kernel, and enables features such as introspection or filtering of data with the help of BPF programs that operate on this data structure. Latter becomes in particular useful for kTLS where data encryption is deferred into the kernel, and as such enabling the kernel to perform L7 introspection and policy based on BPF for TLS connections where the record is being encrypted after BPF has run and came to a verdict. In order to get there, first step is to transform open coding of scatter-gather list handling into a common core framework that subsystems can use. The code itself has been split and refactored into three bigger pieces: i) the generic sk_msg API which deals with managing the scatter gather ring, providing helpers for walking and mangling, transferring application data from user space into it, and preparing it for BPF pre/post-processing, ii) the plain sock map itself where sockets can be attached to or detached from; these bits are independent of i) which can now be used also without sock map, and iii) the integration with plain TCP as one protocol to be used for processing L7 application data (later this could e.g. also be extended to other protocols like UDP). The semantics are the same with the old sock map code and therefore no change of user facing behavior or APIs. While pursuing this work it also helped finding a number of bugs in the old sockmap code that we've fixed already in earlier commits. The test_sockmap kselftest suite passes through fine as well. Joint work with John. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15tcp, ulp: remove ulp bits from sockmapDaniel Borkmann
In order to prepare sockmap logic to be used in combination with kTLS we need to detangle it from ULP, and further split it in later commits into a generic API. Joint work with John. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2018-10-14 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) Fix xsk map update and delete operation to not call synchronize_net() but to piggy back on SOCK_RCU_FREE for sockets instead as we are not allowed to sleep under RCU, from Björn. 2) Do not change RLIMIT_MEMLOCK in reuseport_bpf selftest if the process already has unlimited RLIMIT_MEMLOCK, from Eric. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts were easy to resolve using immediate context mostly, except the cls_u32.c one where I simply too the entire HEAD chunk. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12bpf: wait for running BPF programs when updating map-in-mapDaniel Colascione
The map-in-map frequently serves as a mechanism for atomic snapshotting of state that a BPF program might record. The current implementation is dangerous to use in this way, however, since userspace has no way of knowing when all programs that might have retrieved the "old" value of the map may have completed. This change ensures that map update operations on map-in-map map types always wait for all references to the old map to drop before returning to userspace. Signed-off-by: Daniel Colascione <dancol@google.com> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-12tracing: probeevent: Fix uninitialized used of offset in parse argsSteven Rostedt (VMware)
Dan's smatch utility found an uninitialized use of offset in a path in parse_probe_args(). Unless an offset is specifically specified for commands that allow them, it should default to zero. Link: http://lkml.kernel.org/r/20181012134246.5doqaobxunlqqs53@mwanda Fixes: 533059281ee5 ("tracing: probeevent: Introduce new argument fetching code") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> (smatch) Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-12Merge branch 'for-linus' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input Dmitry writes: "Input updates for v4.19-rc7 - we added a few scheduling points into various input interfaces to ensure that large writes will not cause RCU stalls - fixed configuring PS/2 keyboards as wakeup devices on newer platforms - added a new Xbox gamepad ID." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: uinput - add a schedule point in uinput_inject_events() Input: evdev - add a schedule point in evdev_write() Input: mousedev - add a schedule point in mousedev_write() Input: i8042 - enable keyboard wakeups by default when s2idle is used Input: xpad - add support for Xbox1 PDP Camo series gamepad
2018-10-12printk: fix integer overflow in setup_log_buf()Sergey Senozhatsky
The way we calculate logbuf free space percentage overflows signed integer: int free; free = __LOG_BUF_LEN - log_next_idx; pr_info("early log buf free: %u(%u%%)\n", free, (free * 100) / __LOG_BUF_LEN); We support LOG_BUF_LEN of up to 1<<25 bytes. Since setup_log_buf() is called during early init, logbuf is mostly empty, so __LOG_BUF_LEN - log_next_idx is close to 1<<25. Thus when we multiply it by 100, we overflow signed integer value range: 100 is 2^6 + 2^5 + 2^2. Example, booting with LOG_BUF_LEN 1<<25 and log_buf_len=2G boot param: [ 0.075317] log_buf_len: -2147483648 bytes [ 0.075319] early log buf free: 33549896(-28%) Make "free" unsigned integer and use appropriate printk() specifier. Link: http://lkml.kernel.org/r/20181010113308.9337-1-sergey.senozhatsky@gmail.com To: Steven Rostedt <rostedt@goodmis.org> Cc: linux-kernel@vger.kernel.org Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12printk: do not preliminary split up cont bufferSergey Senozhatsky
We have a proper 'overflow' check which tells us that we need to split up existing cont buffer in separate records: if (cont.len + len > sizeof(cont.buf)) cont_flush(); At the same time we also have one extra flush: "if cont buffer is 80% full then split it up" in cont_add(): if (cont.len > (sizeof(cont.buf) * 80) / 100) cont_flush(); This looks to be redundant, since the existing "overflow" check should work just fine, so remove this 80% check and wait for either a normal cont termination \n, for preliminary flush due to possible buffer overflow or for preliminary flush due to cont race. Link: http://lkml.kernel.org/r/20181002023836.4487-4-sergey.senozhatsky@gmail.com To: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: LKML <linux-kernel@vger.kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12printk: lock/unlock console only for new logbuf entriesSergey Senozhatsky
Prior to commit 5c2992ee7fd8a29 ("printk: remove console flushing special cases for partial buffered lines") we would do console_cont_flush() for each pr_cont() to print cont fragments, so console_unlock() would actually print data: pr_cont(); console_lock(); console_unlock() console_cont_flush(); // print cont fragment ... pr_cont(); console_lock(); console_unlock() console_cont_flush(); // print cont fragment We don't do console_cont_flush() anymore, so when we do pr_cont() console_unlock() does nothing (unless we flushed the cont buffer): pr_cont(); console_lock(); console_unlock(); // noop ... pr_cont(); console_lock(); console_unlock(); // noop ... pr_cont(); cont_flush(); console_lock(); console_unlock(); // print data We also wakeup klogd purposelessly for pr_cont() output - un-flushed cont buffer is not stored in log_buf; there is nothing to pull. Thus we can console_lock()/console_unlock()/wake_up_klogd() only when we know that we log_store()-ed a message and there is something to print to the consoles/syslog. Link: http://lkml.kernel.org/r/20181002023836.4487-3-sergey.senozhatsky@gmail.com To: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: LKML <linux-kernel@vger.kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12printk: keep kernel cont support always enabledSergey Senozhatsky
Since commit 5c2992ee7fd8a29 ("printk: remove console flushing special cases for partial buffered lines") we don't print cont fragments to the consoles; cont lines are now proper log_buf entries and there is no "consecutive continuation flag" anymore: we either have 'c' entries that mark continuation lines without fragments; or '-' entries that mark normal logbuf entries. There are no '+' entries anymore. However, we still have a small leftover - presence of ext_console drivers disables kernel cont support and we flush each pr_cont() and store it as a separate log_buf entry. Previously, it worked because msg_print_ext_header() had that "an optional external merge of the records" functionality: if (msg->flags & LOG_CONT) cont = (prev_flags & LOG_CONT) ? '+' : 'c'; We don't do this as of now, so keep kernel cont always enabled. Note from pmladek: The original purpose was to get full information including the metadata and dictionary via extended console drivers, see commit 6fe29354befe4c46e ("printk: implement support for extended console drivers"). The dictionary probably was the most important part but it was actually lost: static void cont_flush(void) { [...] log_store(cont.facility, cont.level, cont.flags, cont.ts_nsec, NULL, 0, cont.buf, cont.len); Nobody noticed because the only dictionary user is dev_printk() and dev_cont() is _not_ defined. Link: http://lkml.kernel.org/r/20181002023836.4487-2-sergey.senozhatsky@gmail.com To: Steven Rostedt <rostedt@goodmis.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: LKML <linux-kernel@vger.kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> [pmladek@suse.com: Updated commit message] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-11Merge branch 'for-4.19-fixes' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Tejun writes: "cgroup fixes for v4.19-rc7 One cgroup2 threaded mode fix for v4.19-rc7. While threaded mode isn't used widely (yet) and the bug requires somewhat convoluted sequence of operations, it causes a userland visible malfunction - EINVAL on a valid attempt to enable threaded mode. This pull request contains the fix" * 'for-4.19-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Fix dom_cgrp propagation when enabling threaded mode
2018-10-11sched/fair: Fix throttle_list starvation with low CFS quotaPhil Auld
With a very low cpu.cfs_quota_us setting, such as the minimum of 1000, distribute_cfs_runtime may not empty the throttled_list before it runs out of runtime to distribute. In that case, due to the change from c06f04c7048 to put throttled entries at the head of the list, later entries on the list will starve. Essentially, the same X processes will get pulled off the list, given CPU time and then, when expired, get put back on the head of the list where distribute_cfs_runtime will give runtime to the same set of processes leaving the rest. Fix the issue by setting a bit in struct cfs_bandwidth when distribute_cfs_runtime is running, so that the code in throttle_cfs_rq can decide to put the throttled entry on the tail or the head of the list. The bit is set/cleared by the callers of distribute_cfs_runtime while they hold cfs_bandwidth->lock. This is easy to reproduce with a handful of CPU consumers. I use 'crash' on the live system. In some cases you can simply look at the throttled list and see the later entries are not changing: crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1" "$4}' | pr -t -n3 1 ffff90b56cb2d200 -976050 2 ffff90b56cb2cc00 -484925 3 ffff90b56cb2bc00 -658814 4 ffff90b56cb2ba00 -275365 5 ffff90b166a45600 -135138 6 ffff90b56cb2da00 -282505 7 ffff90b56cb2e000 -148065 8 ffff90b56cb2fa00 -872591 9 ffff90b56cb2c000 -84687 10 ffff90b56cb2f000 -87237 11 ffff90b166a40a00 -164582 crash> list cfs_rq.throttled_list -H 0xffff90b54f6ade40 -s cfs_rq.runtime_remaining | paste - - | awk '{print $1" "$4}' | pr -t -n3 1 ffff90b56cb2d200 -994147 2 ffff90b56cb2cc00 -306051 3 ffff90b56cb2bc00 -961321 4 ffff90b56cb2ba00 -24490 5 ffff90b166a45600 -135138 6 ffff90b56cb2da00 -282505 7 ffff90b56cb2e000 -148065 8 ffff90b56cb2fa00 -872591 9 ffff90b56cb2c000 -84687 10 ffff90b56cb2f000 -87237 11 ffff90b166a40a00 -164582 Sometimes it is easier to see by finding a process getting starved and looking at the sched_info: crash> task ffff8eb765994500 sched_info PID: 7800 TASK: ffff8eb765994500 CPU: 16 COMMAND: "cputest" sched_info = { pcount = 8, run_delay = 697094208, last_arrival = 240260125039, last_queued = 240260327513 }, crash> task ffff8eb765994500 sched_info PID: 7800 TASK: ffff8eb765994500 CPU: 16 COMMAND: "cputest" sched_info = { pcount = 8, run_delay = 697094208, last_arrival = 240260125039, last_queued = 240260327513 }, Signed-off-by: Phil Auld <pauld@redhat.com> Reviewed-by: Ben Segall <bsegall@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: c06f04c70489 ("sched: Fix potential near-infinite distribute_cfs_runtime() loop") Link: http://lkml.kernel.org/r/20181008143639.GA4019@pauld.bos.csb Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-11xsk: do not call synchronize_net() under RCU read lockBjörn Töpel
The XSKMAP update and delete functions called synchronize_net(), which can sleep. It is not allowed to sleep during an RCU read section. Instead we need to make sure that the sock sk_destruct (xsk_destruct) function is asynchronously called after an RCU grace period. Setting the SOCK_RCU_FREE flag for XDP sockets takes care of this. Fixes: fbfc504a24f5 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP") Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-10tracing/kprobes: Allow kprobe-events to record module symbolMasami Hiramatsu
Allow kprobe-events to record module symbols. Since data symbols in a non-loaded module doesn't exist, it fails to define such symbol as an argument of kprobe-event. But if the kprobe event is defined on that module, we can defer to resolve the symbol address. Note that if given symbol is not found, the event is kept unavailable. User can enable it but the event is not recorded. Link: http://lkml.kernel.org/r/153547312336.26502.11432902826345374463.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing/kprobes: Check the probe on unloaded module correctlyMasami Hiramatsu
Current kprobe event doesn't checks correctly whether the given event is on unloaded module or not. It just checks the event has ":" in the name. That is not enough because if we define a probe on non-exist symbol on loaded module, it allows to define that (with warning message) To ensure it correctly, this searches the module name on loaded module list and only if there is not, it allows to define it. (this event will be available when the target module is loaded) Link: http://lkml.kernel.org/r/153547309528.26502.8300278470528281328.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing/uprobes: Fix to return -EFAULT if copy_from_user failedMasami Hiramatsu
Fix probe_mem_read() to return -EFAULT if copy_from_user() failed. The copy_from_user() returns remaining bytes when it failed, but probe_mem_read() caller expects it returns error code like as probe_kernel_read(). Link: http://lkml.kernel.org/r/153547306719.26502.8353484532699160223.stgit@devbox Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Add $argN for accessing function argsMasami Hiramatsu
Add $argN special fetch variable for accessing function arguments. This allows user to trace the Nth argument easily at the function entry. Note that this returns most probably assignment of registers and stacks. In some case, it may not work well. If you need to access correct registers or stacks you should use perf-probe. Link: http://lkml.kernel.org/r/152465888632.26224.3412465701570253696.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Add array type supportMasami Hiramatsu
Add array type support for probe events. This allows user to get arraied types from memory address. The array type syntax is TYPE[N] Where TYPE is one of types (u8/16/32/64,s8/16/32/64, x8/16/32/64, symbol, string) and N is a fixed value less than 64. The string array type is a bit different from other types. For other base types, <base-type>[1] is equal to <base-type> (e.g. +0(%di):x32[1] is same as +0(%di):x32.) But string[1] is not equal to string. The string type itself represents "char array", but string array type represents "char * array". So, for example, +0(%di):string[1] is equal to +0(+0(%di)):string. Link: http://lkml.kernel.org/r/152465891533.26224.6150658225601339931.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Add symbol typeMasami Hiramatsu
Add "symbol" type to probeevent, which is an alias of u32 or u64 (depends on BITS_PER_LONG). This shows the result value in symbol+offset style. This type is only available with kprobe events. Link: http://lkml.kernel.org/r/152465882860.26224.14779072294412467338.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Unify fetch_insn processing common partMasami Hiramatsu
Unify the fetch_insn bottom process (from stage 2: dereference indirect data) from kprobe and uprobe events, since those are mostly same. Link: http://lkml.kernel.org/r/152465879965.26224.8547240824606804815.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Append traceprobe_ for exported functionMasami Hiramatsu
Append traceprobe_ for exported function set_print_fmt() as same as other functions. Link: http://lkml.kernel.org/r/152465877071.26224.11143125027282999726.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Return consumed bytes of dynamic areaMasami Hiramatsu
Cleanup string fetching routine so that returns the consumed bytes of dynamic area and store the string information as data_loc format instead of data_rloc. This simplifies the fetcharg loop. Link: http://lkml.kernel.org/r/152465874163.26224.12125143907501289031.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Unify fetch type tablesMasami Hiramatsu
Unify {k,u}probe_fetch_type_table to probe_fetch_type_table because the main difference of those type tables (fetcharg methods) are gone. Now we can consolidate it. Link: http://lkml.kernel.org/r/152465871274.26224.13999436317830479698.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Introduce new argument fetching codeMasami Hiramatsu
Replace {k,u}probe event argument fetching framework with switch-case based. Currently that is implemented with structures, macros and chain of function-pointers, which is more complicated than necessary and may get a performance penalty by retpoline. This simplify that with an array of "fetch_insn" (opcode and oprands), and make process_fetch_insn() just interprets it. No function pointers are used. Link: http://lkml.kernel.org/r/152465868340.26224.2551120475197839464.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Remove NOKPROBE_SYMBOL from print functionsMasami Hiramatsu
Remove unneeded NOKPROBE_SYMBOL from print functions since the print functions are only used when printing out the trace data, and not from kprobe handler. Link: http://lkml.kernel.org/r/152465865422.26224.10111548170594014954.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Cleanup argument field definitionMasami Hiramatsu
Cleanup event argument definition code in one place for maintenancability. Link: http://lkml.kernel.org/r/152465862529.26224.9068605421476018902.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Cleanup print argument functionsMasami Hiramatsu
Cleanup the print-argument function to decouple it into print-name and print-value, so that it can support more flexible expression, like array type. Link: http://lkml.kernel.org/r/152465859635.26224.13452846788717102315.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10trace_uprobe: support reference counter in fd-based uprobeSong Liu
This patch enables uprobes with reference counter in fd-based uprobe. Highest 32 bits of perf_event_attr.config is used to stored offset of the reference count (semaphore). Format information in /sys/bus/event_source/devices/uprobe/format/ is updated to reflect this new feature. Link: http://lkml.kernel.org/r/20181002053636.1896903-1-songliubraving@fb.com Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10signal: Guard against negative signal numbers in copy_siginfo_from_user32Eric W. Biederman
While fixing an out of bounds array access in known_siginfo_layout reported by the kernel test robot it became apparent that the same bug exists in siginfo_layout and affects copy_siginfo_from_user32. The straight forward fix that makes guards against making this mistake in the future and should keep the code size small is to just take an unsigned signal number instead of a signed signal number, as I did to fix known_siginfo_layout. Cc: stable@vger.kernel.org Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-10signal: Guard against negative signal numbers in copy_siginfo_from_userEric W. Biederman
The bounds checks in known_siginfo_layout only guards against positive numbers that are too large, large negative can slip through and can cause out of bounds accesses. Ordinarily this is not a concern because early in signal processing the signal number is filtered with valid_signal which ensures it is a small positive signal number, but copy_siginfo_from_user is called before this check is performed. [ 73.031126] BUG: unable to handle kernel paging request at ffffffff6281bcb6 [ 73.032038] PGD 3014067 P4D 3014067 PUD 0 [ 73.032565] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI [ 73.033287] CPU: 0 PID: 732 Comm: trinity-c3 Tainted: G W T 4.19.0-rc1-00077-g4ce5f9c #1 [ 73.034423] RIP: 0010:copy_siginfo_from_user+0x4d/0xd0 [ 73.034908] Code: 00 8b 53 08 81 fa 80 00 00 00 0f 84 90 00 00 00 85 d2 7e 2d 48 63 0b 83 f9 1f 7f 1c 8d 71 ff bf d8 04 01 50 48 0f a3 f7 73 0e <0f> b6 8c 09 20 bb 81 82 39 ca 7f 15 eb 68 31 c0 83 fa 06 7f 0c eb [ 73.036665] RSP: 0018:ffff88001b8f7e20 EFLAGS: 00010297 [ 73.037160] RAX: 0000000000000000 RBX: ffff88001b8f7e90 RCX: fffffffff00000cb [ 73.037865] RDX: 0000000000000001 RSI: 00000000f00000ca RDI: 00000000500104d8 [ 73.038546] RBP: ffff88001b8f7e80 R08: 0000000000000000 R09: 0000000000000000 [ 73.039201] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000008 [ 73.039874] R13: 00000000000002dc R14: 0000000000000000 R15: 0000000000000000 [ 73.040613] FS: 000000000104a880(0000) GS:ffff88001f000000(0000) knlGS:0000000000000000 [ 73.041649] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 73.042405] CR2: ffffffff6281bcb6 CR3: 000000001cb52003 CR4: 00000000001606b0 [ 73.043351] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 73.044286] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 [ 73.045221] Call Trace: [ 73.045556] __x64_sys_rt_tgsigqueueinfo+0x34/0xa0 [ 73.046199] do_syscall_64+0x1a4/0x390 [ 73.046708] ? vtime_user_enter+0x61/0x80 [ 73.047242] ? __context_tracking_enter+0x4e/0x60 [ 73.047714] ? __context_tracking_enter+0x4e/0x60 [ 73.048278] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Therefore fix known_siginfo_layout to take an unsigned signal number instead of a signed signal number. All valid signal numbers are small positive numbers so they will not be affected, but invalid negative signal numbers will now become large positive signal numbers and will not be used as indices into the sig_sicodes array. Making the signal number unsigned makes it difficult for similar mistakes to happen in the future. Fixes: 4ce5f9c9e754 ("signal: Use a smaller struct siginfo in the kernel") Inspired-by: Sean Christopherson <sean.j.christopherson@intel.com> Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-10-10tick/sched : Remove redundant cpu_online() checkPeng Hao
can_stop_idle_tick() checks cpu_online() twice. The first check leaves the function when the CPU is not online, so the second check it redundant. Remove it. Signed-off-by: Peng Hao <peng.hao2@zte.com.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: fweisbec@gmail.com Link: https://lkml.kernel.org/r/1539099815-2943-1-git-send-email-penghao122@sina.com.cn
2018-10-09bpf: return EOPNOTSUPP when map lookup isn't supportedPrashant Bhole
Return ERR_PTR(-EOPNOTSUPP) from map_lookup_elem() methods of below map types: - BPF_MAP_TYPE_PROG_ARRAY - BPF_MAP_TYPE_STACK_TRACE - BPF_MAP_TYPE_XSKMAP - BPF_MAP_TYPE_SOCKMAP/BPF_MAP_TYPE_SOCKHASH Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09bpf: error handling when map_lookup_elem isn't supportedPrashant Bhole
The error value returned by map_lookup_elem doesn't differentiate whether lookup was failed because of invalid key or lookup is not supported. Lets add handling for -EOPNOTSUPP return value of map_lookup_elem() method of map, with expectation from map's implementation that it should return -EOPNOTSUPP if lookup is not supported. The errno for bpf syscall for BPF_MAP_LOOKUP_ELEM command will be set to EOPNOTSUPP if map lookup is not supported. Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09bpf: btf: Fix a missing check bugWenwen Wang
In btf_parse_hdr(), the length of the btf data header is firstly copied from the user space to 'hdr_len' and checked to see whether it is larger than 'btf_data_size'. If yes, an error code EINVAL is returned. Otherwise, the whole header is copied again from the user space to 'btf->hdr'. However, after the second copy, there is no check between 'btf->hdr->hdr_len' and 'hdr_len' to confirm that the two copies get the same value. Given that the btf data is in the user space, a malicious user can race to change the data between the two copies. By doing so, the user can provide malicious data to the kernel and cause undefined behavior. This patch adds a necessary check after the second copy, to make sure 'btf->hdr->hdr_len' has the same value as 'hdr_len'. Otherwise, an error code EINVAL will be returned. Signed-off-by: Wenwen Wang <wang6495@umn.edu> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-09resource: Clean it up a bitBorislav Petkov
- Drop BUG_ON()s and do normal error handling instead, in find_next_iomem_res(). - Align function arguments on opening braces. - Get rid of local var sibling_only in find_next_iomem_res(). - Shorten unnecessarily long first_level_children_only arg name. Signed-off-by: Borislav Petkov <bp@suse.de> CC: Andrew Morton <akpm@linux-foundation.org> CC: Bjorn Helgaas <bhelgaas@google.com> CC: Brijesh Singh <brijesh.singh@amd.com> CC: Dan Williams <dan.j.williams@intel.com> CC: H. Peter Anvin <hpa@zytor.com> CC: Lianbo Jiang <lijiang@redhat.com> CC: Takashi Iwai <tiwai@suse.de> CC: Thomas Gleixner <tglx@linutronix.de> CC: Tom Lendacky <thomas.lendacky@amd.com> CC: Vivek Goyal <vgoyal@redhat.com> CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com> CC: bhe@redhat.com CC: dan.j.williams@intel.com CC: dyoung@redhat.com CC: kexec@lists.infradead.org CC: mingo@redhat.com Link: <new submission>
2018-10-09resource: Fix find_next_iomem_res() iteration issueBjorn Helgaas
Previously find_next_iomem_res() used "*res" as both an input parameter for the range to search and the type of resource to search for, and an output parameter for the resource we found, which makes the interface confusing. The current callers use find_next_iomem_res() incorrectly because they allocate a single struct resource and use it for repeated calls to find_next_iomem_res(). When find_next_iomem_res() returns a resource, it overwrites the start, end, flags, and desc members of the struct. If we call find_next_iomem_res() again, we must update or restore these fields. The previous code restored res.start and res.end, but not res.flags or res.desc. Since the callers did not restore res.flags, if they searched for flags IORESOURCE_MEM | IORESOURCE_BUSY and found a resource with flags IORESOURCE_MEM | IORESOURCE_BUSY | IORESOURCE_SYSRAM, the next search would incorrectly skip resources unless they were also marked as IORESOURCE_SYSRAM. Fix this by restructuring the interface so it takes explicit "start, end, flags" parameters and uses "*res" only as an output parameter. Based on a patch by Lianbo Jiang <lijiang@redhat.com>. [ bp: While at it: - make comments kernel-doc style. - Originally-by: http://lore.kernel.org/lkml/20180921073211.20097-2-lijiang@redhat.com Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> CC: Andrew Morton <akpm@linux-foundation.org> CC: Brijesh Singh <brijesh.singh@amd.com> CC: Dan Williams <dan.j.williams@intel.com> CC: H. Peter Anvin <hpa@zytor.com> CC: Lianbo Jiang <lijiang@redhat.com> CC: Takashi Iwai <tiwai@suse.de> CC: Thomas Gleixner <tglx@linutronix.de> CC: Tom Lendacky <thomas.lendacky@amd.com> CC: Vivek Goyal <vgoyal@redhat.com> CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com> CC: bhe@redhat.com CC: dan.j.williams@intel.com CC: dyoung@redhat.com CC: kexec@lists.infradead.org CC: mingo@redhat.com CC: x86-ml <x86@kernel.org> Link: http://lkml.kernel.org/r/153805812916.1157.177580438135143788.stgit@bhelgaas-glaptop.roam.corp.google.com
2018-10-09resource: Include resource end in walk_*() interfacesBjorn Helgaas
find_next_iomem_res() finds an iomem resource that covers part of a range described by "start, end". All callers expect that range to be inclusive, i.e., both start and end are included, but find_next_iomem_res() doesn't handle the end address correctly. If it finds an iomem resource that contains exactly the end address, it skips it, e.g., if "start, end" is [0x0-0x10000] and there happens to be an iomem resource [mem 0x10000-0x10000] (the single byte at 0x10000), we skip it: find_next_iomem_res(...) { start = 0x0; end = 0x10000; for (p = next_resource(...)) { # p->start = 0x10000; # p->end = 0x10000; # we *should* return this resource, but this condition is false: if ((p->end >= start) && (p->start < end)) break; Adjust find_next_iomem_res() so it allows a resource that includes the single byte at the end of the range. This is a corner case that we probably don't see in practice. Fixes: 58c1b5b07907 ("[PATCH] memory hotadd fixes: find_next_system_ram catch range fix") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Borislav Petkov <bp@suse.de> CC: Andrew Morton <akpm@linux-foundation.org> CC: Brijesh Singh <brijesh.singh@amd.com> CC: Dan Williams <dan.j.williams@intel.com> CC: H. Peter Anvin <hpa@zytor.com> CC: Lianbo Jiang <lijiang@redhat.com> CC: Takashi Iwai <tiwai@suse.de> CC: Thomas Gleixner <tglx@linutronix.de> CC: Tom Lendacky <thomas.lendacky@amd.com> CC: Vivek Goyal <vgoyal@redhat.com> CC: Yaowei Bai <baiyaowei@cmss.chinamobile.com> CC: bhe@redhat.com CC: dan.j.williams@intel.com CC: dyoung@redhat.com CC: kexec@lists.infradead.org CC: mingo@redhat.com CC: x86-ml <x86@kernel.org> Link: http://lkml.kernel.org/r/153805812254.1157.16736368485811773752.stgit@bhelgaas-glaptop.roam.corp.google.com
2018-10-09smp,cpumask: introduce on_each_cpu_cond_maskRik van Riel
Introduce a variant of on_each_cpu_cond that iterates only over the CPUs in a cpumask, in order to avoid making callbacks for every single CPU in the system when we only need to test a subset. Cc: npiggin@gmail.com Cc: mingo@kernel.org Cc: will.deacon@arm.com Cc: songliubraving@fb.com Cc: kernel-team@fb.com Cc: hpa@zytor.com Cc: luto@kernel.org Signed-off-by: Rik van Riel <riel@surriel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180926035844.1420-5-riel@surriel.com
2018-10-09smp: use __cpumask_set_cpu in on_each_cpu_condRik van Riel
The code in on_each_cpu_cond sets CPUs in a locally allocated bitmask, which should never be used by other CPUs simultaneously. There is no need to use locked memory accesses to set the bits in this bitmap. Switch to __cpumask_set_cpu. Cc: npiggin@gmail.com Cc: mingo@kernel.org Cc: will.deacon@arm.com Cc: songliubraving@fb.com Cc: kernel-team@fb.com Cc: hpa@zytor.com Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Rik van Riel <riel@surriel.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/20180926035844.1420-4-riel@surriel.com
2018-10-09dma-direct: respect DMA_ATTR_NO_WARNChristoph Hellwig
Respect the DMA_ATTR_NO_WARN flags for allocations in dma-direct. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Robin Murphy <robin.murphy@arm.com>
2018-10-09printk: Give error on attempt to set log buffer length to over 2GHe Zhe
The current printk() is ready to handle log buffer size up to 2G. Give an explicit error for users who want to use larger log buffer. Also fix printk formatting to show the 2G as a positive number. Link: http://lkml.kernel.org/r/20181008135916.gg4kkmoki5bgtco5@pathway.suse.cz Cc: rostedt@goodmis.org Cc: linux-kernel@vger.kernel.org Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: He Zhe <zhe.he@windriver.com> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> [pmladek: Fixed to the really safe limit 2GB.] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-09futex: Replace spin_is_locked() with lockdepLance Roy
lockdep_assert_held() is better suited for checking locking requirements, since it won't get confused when the lock is held by some other task. This is also a step towards possibly removing spin_is_locked(). Signed-off-by: Lance Roy <ldr709@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "Paul E. McKenney" <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Darren Hart <dvhart@infradead.org> Link: https://lkml.kernel.org/r/20181003053902.6910-12-ldr709@gmail.com