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* Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-06-251-25/+46
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "A few fixes for timekeeping and timers: - Plug a subtle race due to a missing READ_ONCE() in the timekeeping code where reloading of a pointer results in an inconsistent callback argument being supplied to the clocksource->read function. - Correct the CLOCK_MONOTONIC_RAW sub-nanosecond accounting in the time keeping core code, to prevent a possible discontuity. - Apply a similar fix to the arm64 vdso clock_gettime() implementation - Add missing includes to clocksource drivers, which relied on indirect includes which fails in certain configs. - Use the proper iomem pointer for read/iounmap in a probe function" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW time: Fix CLOCK_MONOTONIC_RAW sub-nanosecond accounting time: Fix clock->read(clock) race around clocksource changes clocksource: Explicitly include linux/clocksource.h when needed clocksource/drivers/arm_arch_timer: Fix read and iounmap of incorrect variable
| * time: Fix CLOCK_MONOTONIC_RAW sub-nanosecond accountingJohn Stultz2017-06-201-9/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Due to how the MONOTONIC_RAW accumulation logic was handled, there is the potential for a 1ns discontinuity when we do accumulations. This small discontinuity has for the most part gone un-noticed, but since ARM64 enabled CLOCK_MONOTONIC_RAW in their vDSO clock_gettime implementation, we've seen failures with the inconsistency-check test in kselftest. This patch addresses the issue by using the same sub-ns accumulation handling that CLOCK_MONOTONIC uses, which avoids the issue for in-kernel users. Since the ARM64 vDSO implementation has its own clock_gettime calculation logic, this patch reduces the frequency of errors, but failures are still seen. The ARM64 vDSO will need to be updated to include the sub-nanosecond xtime_nsec values in its calculation for this issue to be completely fixed. Signed-off-by: John Stultz <john.stultz@linaro.org> Tested-by: Daniel Mentz <danielmentz@google.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <stephen.boyd@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Cc: "stable #4 . 8+" <stable@vger.kernel.org> Cc: Miroslav Lichvar <mlichvar@redhat.com> Link: http://lkml.kernel.org/r/1496965462-20003-3-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * time: Fix clock->read(clock) race around clocksource changesJohn Stultz2017-06-201-16/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In tests, which excercise switching of clocksources, a NULL pointer dereference can be observed on AMR64 platforms in the clocksource read() function: u64 clocksource_mmio_readl_down(struct clocksource *c) { return ~(u64)readl_relaxed(to_mmio_clksrc(c)->reg) & c->mask; } This is called from the core timekeeping code via: cycle_now = tkr->read(tkr->clock); tkr->read is the cached tkr->clock->read() function pointer. When the clocksource is changed then tkr->clock and tkr->read are updated sequentially. The code above results in a sequential load operation of tkr->read and tkr->clock as well. If the store to tkr->clock hits between the loads of tkr->read and tkr->clock, then the old read() function is called with the new clock pointer. As a consequence the read() function dereferences a different data structure and the resulting 'reg' pointer can point anywhere including NULL. This problem was introduced when the timekeeping code was switched over to use struct tk_read_base. Before that, it was theoretically possible as well when the compiler decided to reload clock in the code sequence: now = tk->clock->read(tk->clock); Add a helper function which avoids the issue by reading tk_read_base->clock once into a local variable clk and then issue the read function via clk->read(clk). This guarantees that the read() function always gets the proper clocksource pointer handed in. Since there is now no use for the tkr.read pointer, this patch also removes it, and to address stopping the fast timekeeper during suspend/resume, it introduces a dummy clocksource to use rather then just a dummy read function. Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <stephen.boyd@linaro.org> Cc: stable <stable@vger.kernel.org> Cc: Miroslav Lichvar <mlichvar@redhat.com> Cc: Daniel Mentz <danielmentz@google.com> Link: http://lkml.kernel.org/r/1496965462-20003-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2017-06-251-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "Three fixlets for perf: - Return the proper error code if aux buffers for a event are not supported. - Calculate the probe offset for inlined functions correctly - Update the Skylake DTLB load/store miss event so it can count 1G TLB entries as well" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf probe: Fix probe definition for inlined functions perf/x86/intel: Add 1G DTLB load/store miss support for SKL perf/aux: Correct return code of rb_alloc_aux() if !has_aux(ev)
| * | perf/aux: Correct return code of rb_alloc_aux() if !has_aux(ev)Hendrik Brueckner2017-06-211-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the event for which an AUX area is about to be allocated, does not support setting up an AUX area, rb_alloc_aux() return -ENOTSUPP. This error condition is being returned unfiltered to the user space, and, for example, the perf tools fails with: failed to mmap with 524 (INTERNAL ERROR: strerror_r(524, 0x3fff497a1c8, 512)=22) This error can be easily seen with "perf record -m 128,256 -e cpu-clock". The 524 error code maps to -ENOTSUPP (in rb_alloc_aux()). The -ENOTSUPP error code shall be only used within the kernel. So the correct error code would then be -EOPNOTSUPP. With this commit, the perf tool then reports: failed to mmap with 95 (Operation not supported) which is more clear. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pu Hou <bjhoupu@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com> Cc: acme@kernel.org Cc: linux-s390@vger.kernel.org Link: http://lkml.kernel.org/r/1497954399-6355-1-git-send-email-brueckner@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2017-06-241-6/+14
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull timer fix from Eric Biederman: "This fixes an issue of confusing injected signals with the signals from posix timers that has existed since posix timers have been in the kernel. This patch is slightly simpler than my earlier version of this patch as I discovered in testing that I had misspelled "#ifdef CONFIG_POSIX_TIMERS". So I deleted that unnecessary test and made setting of resched_timer uncondtional. I have tested this and verified that without this patch there is a nasty hang that is easy to trigger, and with this patch everything works properly" Thomas Gleixner dixit: "It fixes the problem at hand and covers the ptrace case as well, which I missed. Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: signal: Only reschedule timers on signals timers have sent
| * | signal: Only reschedule timers on signals timers have sentEric W. Biederman2017-06-171-6/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Thomas Gleixner wrote: > The CRIU support added a 'feature' which allows a user space task to send > arbitrary (kernel) signals to itself. The changelog says: > > The kernel prevents sending of siginfo with positive si_code, because > these codes are reserved for kernel. I think we can allow a task to > send such a siginfo to itself. This operation should not be dangerous. > > Quite contrary to that claim, it turns out that it is outright dangerous > for signals with info->si_code == SI_TIMER. The following code sequence in > a user space task allows to crash the kernel: > > id = timer_create(CLOCK_XXX, ..... signo = SIGX); > timer_set(id, ....); > info->si_signo = SIGX; > info->si_code = SI_TIMER: > info->_sifields._timer._tid = id; > info->_sifields._timer._sys_private = 2; > rt_[tg]sigqueueinfo(..., SIGX, info); > sigemptyset(&sigset); > sigaddset(&sigset, SIGX); > rt_sigtimedwait(sigset, info); > > For timers based on CLOCK_PROCESS_CPUTIME_ID, CLOCK_THREAD_CPUTIME_ID this > results in a kernel crash because sigwait() dequeues the signal and the > dequeue code observes: > > info->si_code == SI_TIMER && info->_sifields._timer._sys_private != 0 > > which triggers the following callchain: > > do_schedule_next_timer() -> posix_cpu_timer_schedule() -> arm_timer() > > arm_timer() executes a list_add() on the timer, which is already armed via > the timer_set() syscall. That's a double list add which corrupts the posix > cpu timer list. As a consequence the kernel crashes on the next operation > touching the posix cpu timer list. > > Posix clocks which are internally implemented based on hrtimers are not > affected by this because hrtimer_start() can handle already armed timers > nicely, but it's a reliable way to trigger the WARN_ON() in > hrtimer_forward(), which complains about calling that function on an > already armed timer. This problem has existed since the posix timer code was merged into 2.5.63. A few releases earlier in 2.5.60 ptrace gained the ability to inject not just a signal (which linux has supported since 1.0) but the full siginfo of a signal. The core problem is that the code will reschedule in response to signals getting dequeued not just for signals the timers sent but for other signals that happen to a si_code of SI_TIMER. Avoid this confusion by testing to see if the queued signal was preallocated as all timer signals are preallocated, and so far only the timer code preallocates signals. Move the check for if a timer needs to be rescheduled up into collect_signal where the preallocation check must be performed, and pass the result back to dequeue_signal where the code reschedules timers. This makes it clear why the code cares about preallocated timers. Cc: stable@vger.kernel.org Reported-by: Thomas Gleixner <tglx@linutronix.de> History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Reference: 66dd34ad31e5 ("signal: allow to send any siginfo to itself") Reference: 1669ce53e2ff ("Add PTRACE_GETSIGINFO and PTRACE_SETSIGINFO") Fixes: db8b50ba75f2 ("[PATCH] POSIX clocks & timers") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* | | Merge branch 'for-linus' of ↵Linus Torvalds2017-06-212-7/+37
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull livepatching fix from Jiri Kosina: "Fix the way how livepatches are being stacked with respect to RCU, from Petr Mladek" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: Fix stacking of patches with respect to RCU
| * | livepatch: Fix stacking of patches with respect to RCUPetr Mladek2017-06-202-7/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rcu_read_(un)lock(), list_*_rcu(), and synchronize_rcu() are used for a secure access and manipulation of the list of patches that modify the same function. In particular, it is the variable func_stack that is accessible from the ftrace handler via struct ftrace_ops and klp_ops. Of course, it synchronizes also some states of the patch on the top of the stack, e.g. func->transition in klp_ftrace_handler. At the same time, this mechanism guards also the manipulation of task->patch_state. It is modified according to the state of the transition and the state of the process. Now, all this works well as long as RCU works well. Sadly livepatching might get into some corner cases when this is not true. For example, RCU is not watching when rcu_read_lock() is taken in idle threads. It is because they might sleep and prevent reaching the grace period for too long. There are ways how to make RCU watching even in idle threads, see rcu_irq_enter(). But there is a small location inside RCU infrastructure when even this does not work. This small problematic location can be detected either before calling rcu_irq_enter() by rcu_irq_enter_disabled() or later by rcu_is_watching(). Sadly, there is no safe way how to handle it. Once we detect that RCU was not watching, we might see inconsistent state of the function stack and the related variables in klp_ftrace_handler(). Then we could do a wrong decision, use an incompatible implementation of the function and break the consistency of the system. We could warn but we could not avoid the damage. Fortunately, ftrace has similar problems and they seem to be solved well there. It uses a heavy weight implementation of some RCU operations. In particular, it replaces: + rcu_read_lock() with preempt_disable_notrace() + rcu_read_unlock() with preempt_enable_notrace() + synchronize_rcu() with schedule_on_each_cpu(sync_work) My understanding is that this is RCU implementation from a stone age. It meets the core RCU requirements but it is rather ineffective. Especially, it does not allow to batch or speed up the synchronize calls. On the other hand, it is very trivial. It allows to safely trace and/or livepatch even the RCU core infrastructure. And the effectiveness is a not a big issue because using ftrace or livepatches on productive systems is a rare operation. The safety is much more important than a negligible extra load. Note that the alternative implementation follows the RCU principles. Therefore, we could and actually must use list_*_rcu() variants when manipulating the func_stack. These functions allow to access the pointers in the right order and with the right barriers. But they do not use any other information that would be set only by rcu_read_lock(). Also note that there are actually two problems solved in ftrace: First, it cares about the consistency of RCU read sections. It is being solved the way as described and used in this patch. Second, ftrace needs to make sure that nobody is inside the dynamic trampoline when it is being freed. For this, it also calls synchronize_rcu_tasks() in preemptive kernel in ftrace_shutdown(). Livepatch has similar problem but it is solved by ftrace for free. klp_ftrace_handler() is a good guy and never sleeps. In addition, it is registered with FTRACE_OPS_FL_DYNAMIC. It causes that unregister_ftrace_function() calls: * schedule_on_each_cpu(ftrace_sync) - always * synchronize_rcu_tasks() - in preemptive kernel The effect is that nobody is neither inside the dynamic trampoline nor inside the ftrace handler after unregister_ftrace_function() returns. [jkosina@suse.cz: reformat changelog, fix comment] Signed-off-by: Petr Mladek <pmladek@suse.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-06-183-6/+14
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Three fixlets for timers: - Two hot-fixes for the alarmtimer based posix timers, which prevent a nasty DOS by self rescheduling timers. The proper cleanup of that mess is queued for 4.13 - Make a function static" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick/broadcast: Make tick_broadcast_setup_oneshot() static alarmtimer: Rate limit periodic intervals alarmtimer: Prevent overflow of relative timers
| * | | tick/broadcast: Make tick_broadcast_setup_oneshot() staticStephen Boyd2017-06-122-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This function isn't used outside of tick-broadcast.c, so let's mark it static. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Link: http://lkml.kernel.org/r/20170608063603.13276-1-sboyd@codeaurora.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | alarmtimer: Rate limit periodic intervalsThomas Gleixner2017-06-041-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The alarmtimer code has another source of potentially rearming itself too fast. Interval timers with a very samll interval have a similar CPU hog effect as the previously fixed overflow issue. The reason is that alarmtimers do not implement the normal protection against this kind of problem which the other posix timer use: timer expires -> queue signal -> deliver signal -> rearm timer This scheme brings the rearming under scheduler control and prevents permanently firing timers which hog the CPU. Bringing this scheme to the alarm timer code is a major overhaul because it lacks all the necessary mechanisms completely. So for a quick fix limit the interval to one jiffie. This is not problematic in practice as alarmtimers are usually backed by an RTC for suspend which have 1 second resolution. It could be therefor argued that the resolution of this clock should be set to 1 second in general, but that's outside the scope of this fix. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kostya Serebryany <kcc@google.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170530211655.896767100@linutronix.de
| * | | alarmtimer: Prevent overflow of relative timersThomas Gleixner2017-06-041-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andrey reported a alartimer related RCU stall while fuzzing the kernel with syzkaller. The reason for this is an overflow in ktime_add() which brings the resulting time into negative space and causes immediate expiry of the timer. The following rearm with a small interval does not bring the timer back into positive space due to the same issue. This results in a permanent firing alarmtimer which hogs the CPU. Use ktime_add_safe() instead which detects the overflow and clamps the result to KTIME_SEC_MAX. Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kostya Serebryany <kcc@google.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170530211655.802921648@linutronix.de
* | | | Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds2017-06-182-2/+2
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "Two small fixes for the schedulre core: - Use the proper switch_mm() variant in idle_task_exit() because that code is not called with interrupts disabled. - Fix a confusing typo in a printk" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/core: Idle_task_exit() shouldn't use switch_mm_irqs_off() sched/fair: Fix typo in printk message
| * | | | sched/core: Idle_task_exit() shouldn't use switch_mm_irqs_off()Andy Lutomirski2017-06-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | idle_task_exit() can be called with IRQs on x86 on and therefore should use switch_mm(), not switch_mm_irqs_off(). This doesn't seem to cause any problems right now, but it will confuse my upcoming TLB flush changes. Nonetheless, I think it should be backported because it's trivial. There won't be any meaningful performance impact because idle_task_exit() is only used when offlining a CPU. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@suse.de> 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: f98db6013c55 ("sched/core: Add switch_mm_irqs_off() and use it in the scheduler") Link: http://lkml.kernel.org/r/ca3d1a9fa93a0b49f5a8ff729eda3640fb6abdf9.1497034141.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | sched/fair: Fix typo in printk messageMarcin Nowakowski2017-06-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'schedstats' kernel parameter should be set to enable/disable, so correct the printk hint saying that it should be set to 'enable' rather than 'enabled' to enable scheduler tracepoints. Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1496995229-31245-1-git-send-email-marcin.nowakowski@imgtec.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds2017-06-181-1/+3
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fix from Thomas Gleixner: "Add a missing resource release to an error path" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Release resources in __setup_irq() error path
| * | | | | genirq: Release resources in __setup_irq() error pathHeiner Kallweit2017-06-131-1/+3
| |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case __irq_set_trigger() fails the resources requested via irq_request_resources() are not released. Add the missing release call into the error handling path. Fixes: c1bacbae8192 ("genirq: Provide irq_request/release_resources chip callbacks") Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/655538f5-cb20-a892-ff15-fbd2dd1fa4ec@gmail.com
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*-. | | | | Merge branches 'pm-cpufreq', 'pm-cpuidle' and 'pm-devfreq'Rafael J. Wysocki2017-06-15136-3847/+8988
|\ \| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * pm-cpufreq: cpufreq: conservative: Allow down_threshold to take values from 1 to 10 Revert "cpufreq: schedutil: Reduce frequencies slower" * pm-cpuidle: cpuidle: dt: Add missing 'of_node_put()' * pm-devfreq: PM / devfreq: exynos-ppmu: Staticize event list PM / devfreq: exynos-ppmu: Handle return value of clk_prepare_enable PM / devfreq: exynos-nocp: Handle return value of clk_prepare_enable
| | * | | | Merge branch 'smp-urgent-for-linus' of ↵Linus Torvalds2017-06-101-2/+2
| | |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU hotplug fix from Ingo Molnar: "An error handling corner case fix" * 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: cpu/hotplug: Drop the device lock on error
| | | * | | | cpu/hotplug: Drop the device lock on errorSebastian Andrzej Siewior2017-06-031-2/+2
| | | |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a custom CPU target is specified and that one is not available _or_ can't be interrupted then the code returns to userland without dropping a lock as notices by lockdep: |echo 133 > /sys/devices/system/cpu/cpu7/hotplug/target | ================================================ | [ BUG: lock held when returning to user space! ] | ------------------------------------------------ | bash/503 is leaving the kernel with locks still held! | 1 lock held by bash/503: | #0: (device_hotplug_lock){+.+...}, at: [<ffffffff815b5650>] lock_device_hotplug_sysfs+0x10/0x40 So release the lock then. Fixes: 757c989b9994 ("cpu/hotplug: Make target state writeable") Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170602142714.3ogo25f2wbq6fjpj@linutronix.de
| | * | | | Merge branch 'rcu-urgent-for-linus' of ↵Linus Torvalds2017-06-103-9/+8
| | |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fixes from Ingo Molnar: "Fix an SRCU bug affecting KVM IRQ injection" * 'rcu-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: srcu: Allow use of Classic SRCU from both process and interrupt context srcu: Allow use of Tiny/Tree SRCU from both process and interrupt context
| | | * \ \ \ Merge branch 'rcu/urgent' of ↵Ingo Molnar2017-06-093-9/+8
| | | |\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into rcu/urgent Pull RCU fix from Paul E. McKenney: " This series enables srcu_read_lock() and srcu_read_unlock() to be used from interrupt handlers, which fixes a bug in KVM's use of SRCU in delivery of interrupts to guest OSes. " Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | | | * | | | srcu: Allow use of Classic SRCU from both process and interrupt contextPaolo Bonzini2017-06-081-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linu Cherian reported a WARN in cleanup_srcu_struct() when shutting down a guest running iperf on a VFIO assigned device. This happens because irqfd_wakeup() calls srcu_read_lock(&kvm->irq_srcu) in interrupt context, while a worker thread does the same inside kvm_set_irq(). If the interrupt happens while the worker thread is executing __srcu_read_lock(), updates to the Classic SRCU ->lock_count[] field or the Tree SRCU ->srcu_lock_count[] field can be lost. The docs say you are not supposed to call srcu_read_lock() and srcu_read_unlock() from irq context, but KVM interrupt injection happens from (host) interrupt context and it would be nice if SRCU supported the use case. KVM is using SRCU here not really for the "sleepable" part, but rather due to its IPI-free fast detection of grace periods. It is therefore not desirable to switch back to RCU, which would effectively revert commit 719d93cd5f5c ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING", 2014-01-16). However, the docs are overly conservative. You can have an SRCU instance only has users in irq context, and you can mix process and irq context as long as process context users disable interrupts. In addition, __srcu_read_unlock() actually uses this_cpu_dec() on both Tree SRCU and Classic SRCU. For those two implementations, only srcu_read_lock() is unsafe. When Classic SRCU's __srcu_read_unlock() was changed to use this_cpu_dec(), in commit 5a41344a3d83 ("srcu: Simplify __srcu_read_unlock() via this_cpu_dec()", 2012-11-29), __srcu_read_lock() did two increments. Therefore it kept __this_cpu_inc(), with preempt_disable/enable in the caller. Tree SRCU however only does one increment, so on most architectures it is more efficient for __srcu_read_lock() to use this_cpu_inc(), and any performance differences appear to be down in the noise. Cc: stable@vger.kernel.org Fixes: 719d93cd5f5c ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING") Reported-by: Linu Cherian <linuc.decode@gmail.com> Suggested-by: Linu Cherian <linuc.decode@gmail.com> Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| | | | * | | | srcu: Allow use of Tiny/Tree SRCU from both process and interrupt contextPaolo Bonzini2017-06-082-6/+6
| | | | |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Linu Cherian reported a WARN in cleanup_srcu_struct() when shutting down a guest running iperf on a VFIO assigned device. This happens because irqfd_wakeup() calls srcu_read_lock(&kvm->irq_srcu) in interrupt context, while a worker thread does the same inside kvm_set_irq(). If the interrupt happens while the worker thread is executing __srcu_read_lock(), updates to the Classic SRCU ->lock_count[] field or the Tree SRCU ->srcu_lock_count[] field can be lost. The docs say you are not supposed to call srcu_read_lock() and srcu_read_unlock() from irq context, but KVM interrupt injection happens from (host) interrupt context and it would be nice if SRCU supported the use case. KVM is using SRCU here not really for the "sleepable" part, but rather due to its IPI-free fast detection of grace periods. It is therefore not desirable to switch back to RCU, which would effectively revert commit 719d93cd5f5c ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING", 2014-01-16). However, the docs are overly conservative. You can have an SRCU instance only has users in irq context, and you can mix process and irq context as long as process context users disable interrupts. In addition, __srcu_read_unlock() actually uses this_cpu_dec() on both Tree SRCU and Classic SRCU. For those two implementations, only srcu_read_lock() is unsafe. When Classic SRCU's __srcu_read_unlock() was changed to use this_cpu_dec(), in commit 5a41344a3d83 ("srcu: Simplify __srcu_read_unlock() via this_cpu_dec()", 2012-11-29), __srcu_read_lock() did two increments. Therefore it kept __this_cpu_inc(), with preempt_disable/enable in the caller. Tree SRCU however only does one increment, so on most architectures it is more efficient for __srcu_read_lock() to use this_cpu_inc(), and any performance differences appear to be down in the noise. Unlike Classic and Tree SRCU, Tiny SRCU does increments and decrements on a single variable. Therefore, as Peter Zijlstra pointed out, Tiny SRCU's implementation already supports mixed-context use of srcu_read_lock() and srcu_read_unlock(), at least as long as uses of srcu_read_lock() and srcu_read_unlock() in each handler are nested and paired properly. In other words, it is still illegal to (say) invoke srcu_read_lock() in an interrupt handler and to invoke the matching srcu_read_unlock() in a softirq handler. Therefore, the only change required for Tiny SRCU is to its comments. Fixes: 719d93cd5f5c ("kvm/irqchip: Speed up KVM_SET_GSI_ROUTING") Reported-by: Linu Cherian <linuc.decode@gmail.com> Suggested-by: Linu Cherian <linuc.decode@gmail.com> Cc: kvm@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | | | | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2017-06-101-0/+21
| | |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "This is mostly tooling fixes, plus an instruction pointer filtering fix. It's more fixes than usual - Arnaldo got back from a longer vacation and there was a backlog" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) perf symbols: Kill dso__build_id_is_kmod() perf symbols: Keep DSO->symtab_type after decompress perf tests: Decompress kernel module before objdump perf tools: Consolidate error path in __open_dso() perf tools: Decompress kernel module when reading DSO data perf annotate: Use dso__decompress_kmodule_path() perf tools: Introduce dso__decompress_kmodule_{fd,path} perf tools: Fix a memory leak in __open_dso() perf annotate: Fix symbolic link of build-id cache perf/core: Drop kernel samples even though :u is specified perf script python: Remove dups in documentation examples perf script python: Updated trace_unhandled() signature perf script python: Fix wrong code snippets in documentation perf script: Fix documentation errors perf script: Fix outdated comment for perf-trace-python perf probe: Fix examples section of documentation perf report: Ensure the perf DSO mapping matches what libdw sees perf report: Include partial stacks unwound with libdw perf annotate: Add missing powerpc triplet perf test: Disable breakpoint signal tests for powerpc ...
| | | * | | | | perf/core: Drop kernel samples even though :u is specifiedJin Yao2017-06-081-0/+21
| | | |/ / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When doing sampling, for example: perf record -e cycles:u ... On workloads that do a lot of kernel entry/exits we see kernel samples, even though :u is specified. This is due to skid existing. This might be a security issue because it can leak kernel addresses even though kernel sampling support is disabled. The patch drops the kernel samples if exclude_kernel is specified. For example, test on Haswell desktop: perf record -e cycles:u <mgen> perf report --stdio Before patch applied: 99.77% mgen mgen [.] buf_read 0.20% mgen mgen [.] rand_buf_init 0.01% mgen [kernel.vmlinux] [k] apic_timer_interrupt 0.00% mgen mgen [.] last_free_elem 0.00% mgen libc-2.23.so [.] __random_r 0.00% mgen libc-2.23.so [.] _int_malloc 0.00% mgen mgen [.] rand_array_init 0.00% mgen [kernel.vmlinux] [k] page_fault 0.00% mgen libc-2.23.so [.] __random 0.00% mgen libc-2.23.so [.] __strcasestr 0.00% mgen ld-2.23.so [.] strcmp 0.00% mgen ld-2.23.so [.] _dl_start 0.00% mgen libc-2.23.so [.] sched_setaffinity@@GLIBC_2.3.4 0.00% mgen ld-2.23.so [.] _start We can see kernel symbols apic_timer_interrupt and page_fault. After patch applied: 99.79% mgen mgen [.] buf_read 0.19% mgen mgen [.] rand_buf_init 0.00% mgen libc-2.23.so [.] __random_r 0.00% mgen mgen [.] rand_array_init 0.00% mgen mgen [.] last_free_elem 0.00% mgen libc-2.23.so [.] vfprintf 0.00% mgen libc-2.23.so [.] rand 0.00% mgen libc-2.23.so [.] __random 0.00% mgen libc-2.23.so [.] _int_malloc 0.00% mgen libc-2.23.so [.] _IO_doallocbuf 0.00% mgen ld-2.23.so [.] do_lookup_x 0.00% mgen ld-2.23.so [.] open_verify.constprop.7 0.00% mgen ld-2.23.so [.] _dl_important_hwcaps 0.00% mgen libc-2.23.so [.] sched_setaffinity@@GLIBC_2.3.4 0.00% mgen ld-2.23.so [.] _start There are only userspace symbols. Signed-off-by: Jin Yao <yao.jin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.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: Namhyung Kim <namhyung@kernel.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: acme@kernel.org Cc: jolsa@kernel.org Cc: kan.liang@intel.com Cc: mark.rutland@arm.com Cc: will.deacon@arm.com Cc: yao.jin@intel.com Link: http://lkml.kernel.org/r/1495706947-3744-1-git-send-email-yao.jin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | Merge tag 'pm-4.12-rc5' of ↵Linus Torvalds2017-06-082-26/+5
| | |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fixes from Rafael Wysocki: "These revert one problematic commit related to system sleep and fix one recent intel_pstate regression. Specifics: - Revert a recent commit that attempted to avoid spurious wakeups from suspend-to-idle via ACPI SCI, but introduced regressions on some systems (Rafael Wysocki). We will get back to the problem it tried to address in the next cycle. - Fix a possible division by 0 during intel_pstate initialization due to a missing check (Rafael Wysocki)" * tag 'pm-4.12-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: Revert "ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle" cpufreq: intel_pstate: Avoid division by 0 in min_perf_pct_min()
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| | | *-. \ \ \ \ Merge branches 'intel_pstate' and 'pm-sleep'Rafael J. Wysocki2017-06-092-26/+5
| | | |\ \ \ \ \ \ | | | | |_|_|/ / / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * intel_pstate: cpufreq: intel_pstate: Avoid division by 0 in min_perf_pct_min() * pm-sleep: Revert "ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle"
| | | | | * | | | Revert "ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle"Rafael J. Wysocki2017-06-072-26/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert commit eed4d47efe95 (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle) as it turned out to be premature and triggered a number of different issues on various systems. That includes, but is not limited to, premature suspend-to-RAM aborts on Dell XPS 13 (9343) reported by Dominik. The issue the commit in question attempted to address is real and will need to be taken care of going forward, but evidently more work is needed for this purpose. Reported-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| | * | | | | | | Merge branch 'for-linus' of ↵Linus Torvalds2017-06-081-36/+10
| | |\ \ \ \ \ \ \ | | | |_|_|_|/ / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk Pull printk fix from Petr Mladek: "This reverts a fix added into 4.12-rc1. It caused the kernel log to be printed on another console when two consoles of the same type were defined, e.g. console=ttyS0 console=ttyS1. This configuration was never supported by kernel itself, but it started to make sense with systemd. In other words, the commit broke userspace" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: Revert "printk: fix double printing with earlycon"
| | | * | | | | | Revert "printk: fix double printing with earlycon"Petr Mladek2017-06-081-36/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit cf39bf58afdaabc0b86f141630fb3fd18190294e. The commit regression to users that define both console=ttyS1 and console=ttyS0 on the command line, see https://lkml.kernel.org/r/20170509082915.GA13236@bistromath.localdomain The kernel log messages always appeared only on one serial port. It is even documented in Documentation/admin-guide/serial-console.rst: "Note that you can only define one console per device type (serial, video)." The above mentioned commit changed the order in which the command line parameters are searched. As a result, the kernel log messages go to the last mentioned ttyS* instead of the first one. We long thought that using two console=ttyS* on the command line did not make sense. But then we realized that console= parameters were handled also by systemd, see http://0pointer.de/blog/projects/serial-console.html "By default systemd will instantiate one serial-getty@.service on the main kernel console, if it is not a virtual terminal." where "[4] If multiple kernel consoles are used simultaneously, the main console is the one listed first in /sys/class/tty/console/active, which is the last one listed on the kernel command line." This puts the original report into another light. The system is running in qemu. The first serial port is used to store the messages into a file. The second one is used to login to the system via a socket. It depends on systemd and the historic kernel behavior. By other words, systemd causes that it makes sense to define both console=ttyS1 console=ttyS0 on the command line. The kernel fix caused regression related to userspace (systemd) and need to be reverted. In addition, it went out that the fix helped only partially. The messages still were duplicated when the boot console was removed early by late_initcall(printk_late_init). Then the entire log was replayed when the same console was registered as a normal one. Link: 20170606160339.GC7604@pathway.suse.cz Cc: Aleksey Makarov <aleksey.makarov@linaro.org> Cc: Sabrina Dubroca <sd@queasysnail.net> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Robin Murphy <robin.murphy@arm.com>, Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Nair, Jayachandran" <Jayachandran.Nair@cavium.com> Cc: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reported-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
| | * | | | | | | Merge branch 'for-4.12-fixes' of ↵Linus Torvalds2017-06-052-2/+7
| | |\ \ \ \ \ \ \ | | | |_|/ / / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: "Two cgroup fixes. One to address RCU delay of cpuset removal affecting userland visible behaviors. The other fixes a race condition between controller disable and cgroup removal" * 'for-4.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cpuset: consider dying css as offline cgroup: Prevent kill_css() from being called more than once
| | | * | | | | | cpuset: consider dying css as offlineTejun Heo2017-05-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In most cases, a cgroup controller don't care about the liftimes of cgroups. For the controller, a css becomes online when ->css_online() is called on it and offline when ->css_offline() is called. However, cpuset is special in that the user interface it exposes cares whether certain cgroups exist or not. Combined with the RCU delay between cgroup removal and css offlining, this can lead to user visible behavior oddities where operations which should succeed after cgroup removals fail for some time period. The effects of cgroup removals are delayed when seen from userland. This patch adds css_is_dying() which tests whether offline is pending and updates is_cpuset_online() so that the function returns false also while offline is pending. This gets rid of the userland visible delays. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Daniel Jordan <daniel.m.jordan@oracle.com> Link: http://lkml.kernel.org/r/327ca1f5-7957-fbb9-9e5f-9ba149d40ba2@oracle.com Cc: stable@vger.kernel.org Signed-off-by: Tejun Heo <tj@kernel.org>
| | | * | | | | | cgroup: Prevent kill_css() from being called more than onceWaiman Long2017-05-171-0/+5
| | | | |/ / / / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kill_css() function may be called more than once under the condition that the css was killed but not physically removed yet followed by the removal of the cgroup that is hosting the css. This patch prevents any harmm from being done when that happens. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org # v4.5+
| | * | | | | | Merge branch 'for-linus' of ↵Linus Torvalds2017-06-021-0/+1
| | |\ \ \ \ \ \ | | | | |_|_|/ / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching Pull livepatching fix from Jiri Kosina: "Kconfig dependency fix for livepatching infrastructure from Miroslav Benes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching: livepatch: Make livepatch dependent on !TRIM_UNUSED_KSYMS
| | | * | | | | livepatch: Make livepatch dependent on !TRIM_UNUSED_KSYMSMiroslav Benes2017-05-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If TRIM_UNUSED_KSYMS is enabled, all unneeded exported symbols are made unexported. Two-pass build of the kernel is done to find out which symbols are needed based on a configuration. This effectively complicates things for out-of-tree modules. Livepatch exports functions to (un)register and enable/disable a live patch. The only in-tree module which uses these functions is a sample in samples/livepatch/. If the sample is disabled, the functions are trimmed and out-of-tree live patches cannot be built. Note that live patches are intended to be built out-of-tree. Suggested-by: Michal Marek <mmarek@suse.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Jessica Yu <jeyu@redhat.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
| | * | | | | | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2017-05-271-8/+16
| | |\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixlet from Thomas Gleixner: "Silence dmesg spam by making the posix cpu timer printks depend on print_fatal_signals" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: posix-timers: Make signal printks conditional
| | | * | | | | | posix-timers: Make signal printks conditionalThomas Gleixner2017-05-231-8/+16
| | | | |_|_|_|/ | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A recent commit added extra printks for CPU/RT limits. This can result in excessive spam in dmesg. Make the printks conditional on print_fatal_signals. Fixes: e7ea7c9806a2 ("rlimits: Print more information when CPU/RT limits are exceeded") Reported-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arun Raghavan <arun@arunraghavan.net>
| | * | | | | | Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds2017-05-271-6/+18
| | |\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fix from Thomas Gleixner: "A fix for a state leak which was introduced in the recent rework of futex/rtmutex interaction" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock()
| | | * | | | | | futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock()Peter Zijlstra2017-05-221-6/+18
| | | |/ / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Markus reported that the glibc/nptl/tst-robustpi8 test was failing after commit: cfafcd117da0 ("futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock()") The following trace shows the problem: ld-linux-x86-64-2161 [019] .... 410.760971: SyS_futex: 00007ffbeb76b028: 80000875 op=FUTEX_LOCK_PI ld-linux-x86-64-2161 [019] ...1 410.760972: lock_pi_update_atomic: 00007ffbeb76b028: curval=80000875 uval=80000875 newval=80000875 ret=0 ld-linux-x86-64-2165 [011] .... 410.760978: SyS_futex: 00007ffbeb76b028: 80000875 op=FUTEX_UNLOCK_PI ld-linux-x86-64-2165 [011] d..1 410.760979: do_futex: 00007ffbeb76b028: curval=80000875 uval=80000875 newval=80000871 ret=0 ld-linux-x86-64-2165 [011] .... 410.760980: SyS_futex: 00007ffbeb76b028: 80000871 ret=0000 ld-linux-x86-64-2161 [019] .... 410.760980: SyS_futex: 00007ffbeb76b028: 80000871 ret=ETIMEDOUT Task 2165 does an UNLOCK_PI, assigning the lock to the waiter task 2161 which then returns with -ETIMEDOUT. That wrecks the lock state, because now the owner isn't aware it acquired the lock and removes the pending robust list entry. If 2161 is killed, the robust list will not clear out this futex and the subsequent acquire on this futex will then (correctly) result in -ESRCH which is unexpected by glibc, triggers an internal assertion and dies. Task 2161 Task 2165 rt_mutex_wait_proxy_lock() timeout(); /* T2161 is still queued in the waiter list */ return -ETIMEDOUT; futex_unlock_pi() spin_lock(hb->lock); rtmutex_unlock() remove_rtmutex_waiter(T2161); mark_lock_available(); /* Make the next waiter owner of the user space side */ futex_uval = 2161; spin_unlock(hb->lock); spin_lock(hb->lock); rt_mutex_cleanup_proxy_lock() if (rtmutex_owner() !== current) ... return FAIL; .... return -ETIMEOUT; This means that rt_mutex_cleanup_proxy_lock() needs to call try_to_take_rt_mutex() so it can take over the rtmutex correctly which was assigned by the waker. If the rtmutex is owned by some other task then this call is harmless and just confirmes that the waiter is not able to acquire it. While there, fix what looks like a merge error which resulted in rt_mutex_cleanup_proxy_lock() having two calls to fixup_rt_mutex_waiters() and rt_mutex_wait_proxy_lock() not having any. Both should have one, since both potentially touch the waiter list. Fixes: 38d589f2fd08 ("futex,rt_mutex: Restructure rt_mutex_finish_proxy_lock()") Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Bug-Spotted-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Markus Trippelsdorf <markus@trippelsdorf.de> Link: http://lkml.kernel.org/r/20170519154850.mlomgdsd26drq5j6@hirez.programming.kicks-ass.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | | Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2017-05-271-5/+12
| | |\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull kthread fix from Thomas Gleixner: "A single fix which prevents a use after free when kthread fork fails" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kthread: Fix use-after-free if kthread fork fails
| | | * | | | | | kthread: Fix use-after-free if kthread fork failsVegard Nossum2017-05-221-5/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a kthread forks (e.g. usermodehelper since commit 1da5c46fa965) but fails in copy_process() between calling dup_task_struct() and setting p->set_child_tid, then the value of p->set_child_tid will be inherited from the parent and get prematurely freed by free_kthread_struct(). kthread() - worker_thread() - process_one_work() | - call_usermodehelper_exec_work() | - kernel_thread() | - _do_fork() | - copy_process() | - dup_task_struct() | - arch_dup_task_struct() | - tsk->set_child_tid = current->set_child_tid // implied | - ... | - goto bad_fork_* | - ... | - free_task(tsk) | - free_kthread_struct(tsk) | - kfree(tsk->set_child_tid) - ... - schedule() - __schedule() - wq_worker_sleeping() - kthread_data(task)->flags // UAF The problem started showing up with commit 1da5c46fa965 since it reused ->set_child_tid for the kthread worker data. A better long-term solution might be to get rid of the ->set_child_tid abuse. The comment in set_kthread_struct() also looks slightly wrong. Debugged-by: Jamie Iles <jamie.iles@oracle.com> Fixes: 1da5c46fa965 ("kthread: Make struct kthread kmalloc'ed") Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jamie Iles <jamie.iles@oracle.com> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20170509073959.17858-1-vegard.nossum@oracle.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| | * | | | | | | Merge tag 'trace-v4.12-rc2' of ↵Linus Torvalds2017-05-272-2/+2
| | |\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull ftrace fixes from Steven Rostedt: "There's been a few memory issues found with ftrace. One was simply a memory leak where not all was being freed that should have been in releasing a file pointer on set_graph_function. Then Thomas found that the ftrace trampolines were marked for read/write as well as execute. To shrink the possible attack surface, he added calls to set them to ro. Which also uncovered some other issues with freeing module allocated memory that had its permissions changed. Kprobes had a similar issue which is fixed and a selftest was added to trigger that issue again" * tag 'trace-v4.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: x86/ftrace: Make sure that ftrace trampolines are not RWX x86/mm/ftrace: Do not bug in early boot on irqs_disabled in cpu_flush_range() selftests/ftrace: Add a testcase for many kprobe events kprobes/x86: Fix to set RWX bits correctly before releasing trampoline ftrace: Fix memory leak in ftrace_graph_release()
| | | * | | | | | | kprobes/x86: Fix to set RWX bits correctly before releasing trampolineMasami Hiramatsu2017-05-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix kprobes to set(recover) RWX bits correctly on trampoline buffer before releasing it. Releasing readonly page to module_memfree() crash the kernel. Without this fix, if kprobes user register a bunch of kprobes in function body (since kprobes on function entry usually use ftrace) and unregister it, kernel hits a BUG and crash. Link: http://lkml.kernel.org/r/149570868652.3518.14120169373590420503.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Fixes: d0381c81c2f7 ("kprobes/x86: Set kprobes pages read-only") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| | | * | | | | | | ftrace: Fix memory leak in ftrace_graph_release()Luis Henriques2017-05-261-1/+1
| | | | |/ / / / / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ftrace_hash is being kfree'ed in ftrace_graph_release(), however the ->buckets field is not. This results in a memory leak that is easily captured by kmemleak: unreferenced object 0xffff880038afe000 (size 8192): comm "trace-cmd", pid 238, jiffies 4294916898 (age 9.736s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff815f561e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff8113964d>] __kmalloc+0x12d/0x1a0 [<ffffffff810bf6d1>] alloc_ftrace_hash+0x51/0x80 [<ffffffff810c0523>] __ftrace_graph_open.isra.39.constprop.46+0xa3/0x100 [<ffffffff810c05e8>] ftrace_graph_open+0x68/0xa0 [<ffffffff8114003d>] do_dentry_open.isra.1+0x1bd/0x2d0 [<ffffffff81140df7>] vfs_open+0x47/0x60 [<ffffffff81150f95>] path_openat+0x2a5/0x1020 [<ffffffff81152d6a>] do_filp_open+0x8a/0xf0 [<ffffffff811411df>] do_sys_open+0x12f/0x200 [<ffffffff811412ce>] SyS_open+0x1e/0x20 [<ffffffff815fa6e0>] entry_SYSCALL_64_fastpath+0x13/0x94 [<ffffffffffffffff>] 0xffffffffffffffff Link: http://lkml.kernel.org/r/20170525152038.7661-1-lhenriques@suse.com Cc: stable@vger.kernel.org Fixes: b9b0c831bed2 ("ftrace: Convert graph filter to use hash tables") Signed-off-by: Luis Henriques <lhenriques@suse.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| | * | | | | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2017-05-264-30/+29
| | |\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: 1) Fix state pruning in bpf verifier wrt. alignment, from Daniel Borkmann. 2) Handle non-linear SKBs properly in SCTP ICMP parsing, from Davide Caratti. 3) Fix bit field definitions for rss_hash_type of descriptors in mlx5 driver, from Jesper Brouer. 4) Defer slave->link updates until bonding is ready to do a full commit to the new settings, from Nithin Sujir. 5) Properly reference count ipv4 FIB metrics to avoid use after free situations, from Eric Dumazet and several others including Cong Wang and Julian Anastasov. 6) Fix races in llc_ui_bind(), from Lin Zhang. 7) Fix regression of ESP UDP encapsulation for TCP packets, from Steffen Klassert. 8) Fix mdio-octeon driver Kconfig deps, from Randy Dunlap. 9) Fix regression in setting DSCP on ipv6/GRE encapsulation, from Peter Dawson. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits) ipv4: add reference counting to metrics net: ethernet: ax88796: don't call free_irq without request_irq first ip6_tunnel, ip6_gre: fix setting of DSCP on encapsulated packets sctp: fix ICMP processing if skb is non-linear net: llc: add lock_sock in llc_ui_bind to avoid a race condition bonding: Don't update slave->link until ready to commit test_bpf: Add a couple of tests for BPF_JSGE. bpf: add various verifier test cases bpf: fix wrong exposure of map_flags into fdinfo for lpm bpf: add bpf_clone_redirect to bpf_helper_changes_pkt_data bpf: properly reset caller saved regs after helper call and ld_abs/ind bpf: fix incorrect pruning decision when alignment must be tracked arp: fixed -Wuninitialized compiler warning tcp: avoid fastopen API to be used on AF_UNSPEC net: move somaxconn init from sysctl code net: fix potential null pointer dereference geneve: fix fill_info when using collect_metadata virtio-net: enable TSO/checksum offloads for Q-in-Q vlans be2net: Fix offload features for Q-in-Q packets vlan: Fix tcp checksum offloads in Q-in-Q vlans ...
| | | * | | | | | | bpf: fix wrong exposure of map_flags into fdinfo for lpmDaniel Borkmann2017-05-253-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | trie_alloc() always needs to have BPF_F_NO_PREALLOC passed in via attr->map_flags, since it does not support preallocation yet. We check the flag, but we never copy the flag into trie->map.map_flags, which is later on exposed into fdinfo and used by loaders such as iproute2. Latter uses this in bpf_map_selfcheck_pinned() to test whether a pinned map has the same spec as the one from the BPF obj file and if not, bails out, which is currently the case for lpm since it exposes always 0 as flags. Also copy over flags in array_map_alloc() and stack_map_alloc(). They always have to be 0 right now, but we should make sure to not miss to copy them over at a later point in time when we add actual flags for them to use. Fixes: b95a5c4db09b ("bpf: add a longest prefix match trie map implementation") Reported-by: Jarno Rajahalme <jarno@covalent.io> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * | | | | | | bpf: properly reset caller saved regs after helper call and ld_abs/indDaniel Borkmann2017-05-251-21/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, after performing helper calls, we clear all caller saved registers, that is r0 - r5 and fill r0 depending on struct bpf_func_proto specification. The way we reset these regs can affect pruning decisions in later paths, since we only reset register's imm to 0 and type to NOT_INIT. However, we leave out clearing of other variables such as id, min_value, max_value, etc, which can later on lead to pruning mismatches due to stale data. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * | | | | | | bpf: fix incorrect pruning decision when alignment must be trackedDaniel Borkmann2017-05-251-9/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, when we enforce alignment tracking on direct packet access, the verifier lets the following program pass despite doing a packet write with unaligned access: 0: (61) r2 = *(u32 *)(r1 +76) 1: (61) r3 = *(u32 *)(r1 +80) 2: (61) r7 = *(u32 *)(r1 +8) 3: (bf) r0 = r2 4: (07) r0 += 14 5: (25) if r7 > 0x1 goto pc+4 R0=pkt(id=0,off=14,r=0) R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R7=inv,min_value=0,max_value=1 R10=fp 6: (2d) if r0 > r3 goto pc+1 R0=pkt(id=0,off=14,r=14) R1=ctx R2=pkt(id=0,off=0,r=14) R3=pkt_end R7=inv,min_value=0,max_value=1 R10=fp 7: (63) *(u32 *)(r0 -4) = r0 8: (b7) r0 = 0 9: (95) exit from 6 to 8: R0=pkt(id=0,off=14,r=0) R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R7=inv,min_value=0,max_value=1 R10=fp 8: (b7) r0 = 0 9: (95) exit from 5 to 10: R0=pkt(id=0,off=14,r=0) R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R7=inv,min_value=2 R10=fp 10: (07) r0 += 1 11: (05) goto pc-6 6: safe <----- here, wrongly found safe processed 15 insns However, if we enforce a pruning mismatch by adding state into r8 which is then being mismatched in states_equal(), we find that for the otherwise same program, the verifier detects a misaligned packet access when actually walking that path: 0: (61) r2 = *(u32 *)(r1 +76) 1: (61) r3 = *(u32 *)(r1 +80) 2: (61) r7 = *(u32 *)(r1 +8) 3: (b7) r8 = 1 4: (bf) r0 = r2 5: (07) r0 += 14 6: (25) if r7 > 0x1 goto pc+4 R0=pkt(id=0,off=14,r=0) R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R7=inv,min_value=0,max_value=1 R8=imm1,min_value=1,max_value=1,min_align=1 R10=fp 7: (2d) if r0 > r3 goto pc+1 R0=pkt(id=0,off=14,r=14) R1=ctx R2=pkt(id=0,off=0,r=14) R3=pkt_end R7=inv,min_value=0,max_value=1 R8=imm1,min_value=1,max_value=1,min_align=1 R10=fp 8: (63) *(u32 *)(r0 -4) = r0 9: (b7) r0 = 0 10: (95) exit from 7 to 9: R0=pkt(id=0,off=14,r=0) R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R7=inv,min_value=0,max_value=1 R8=imm1,min_value=1,max_value=1,min_align=1 R10=fp 9: (b7) r0 = 0 10: (95) exit from 6 to 11: R0=pkt(id=0,off=14,r=0) R1=ctx R2=pkt(id=0,off=0,r=0) R3=pkt_end R7=inv,min_value=2 R8=imm1,min_value=1,max_value=1,min_align=1 R10=fp 11: (07) r0 += 1 12: (b7) r8 = 0 13: (05) goto pc-7 <----- mismatch due to r8 7: (2d) if r0 > r3 goto pc+1 R0=pkt(id=0,off=15,r=15) R1=ctx R2=pkt(id=0,off=0,r=15) R3=pkt_end R7=inv,min_value=2 R8=imm0,min_value=0,max_value=0,min_align=2147483648 R10=fp 8: (63) *(u32 *)(r0 -4) = r0 misaligned packet access off 2+15+-4 size 4 The reason why we fail to see it in states_equal() is that the third test in compare_ptrs_to_packet() ... if (old->off <= cur->off && old->off >= old->range && cur->off >= cur->range) return true; ... will let the above pass. The situation we run into is that old->off <= cur->off (14 <= 15), meaning that prior walked paths went with smaller offset, which was later used in the packet access after successful packet range check and found to be safe already. For example: Given is R0=pkt(id=0,off=0,r=0). Adding offset 14 as in above program to it, results in R0=pkt(id=0,off=14,r=0) before the packet range test. Now, testing this against R3=pkt_end with 'if r0 > r3 goto out' will transform R0 into R0=pkt(id=0,off=14,r=14) for the case when we're within bounds. A write into the packet at offset *(u32 *)(r0 -4), that is, 2 + 14 -4, is valid and aligned (2 is for NET_IP_ALIGN). After processing this with all fall-through paths, we later on check paths from branches. When the above skb->mark test is true, then we jump near the end of the program, perform r0 += 1, and jump back to the 'if r0 > r3 goto out' test we've visited earlier already. This time, R0 is of type R0=pkt(id=0,off=15,r=0), and we'll prune that part because this time we'll have a larger safe packet range, and we already found that with off=14 all further insn were already safe, so it's safe as well with a larger off. However, the problem is that the subsequent write into the packet with 2 + 15 -4 is then unaligned, and not caught by the alignment tracking. Note that min_align, aux_off, and aux_off_align were all 0 in this example. Since we cannot tell at this time what kind of packet access was performed in the prior walk and what minimal requirements it has (we might do so in the future, but that requires more complexity), fix it to disable this pruning case for strict alignment for now, and let the verifier do check such paths instead. With that applied, the test cases pass and reject the program due to misalignment. Fixes: d1174416747d ("bpf: Track alignment of register values in the verifier.") Reference: http://patchwork.ozlabs.org/patch/761909/ Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>