summaryrefslogtreecommitdiffstats
Commit message (Collapse)AuthorAgeFilesLines
* Merge branch 'sched-hrtimers-for-linus' of ↵Linus Torvalds2015-06-257-492/+597
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Thomas Gleixner: "This series of scheduler updates depends on sched/core and timers/core branches, which are already in your tree: - Scheduler balancing overhaul to plug a hard to trigger race which causes an oops in the balancer (Peter Zijlstra) - Lockdep updates which are related to the balancing updates (Peter Zijlstra)" * 'sched-hrtimers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched,lockdep: Employ lock pinning lockdep: Implement lock pinning lockdep: Simplify lock_release() sched: Streamline the task migration locking a little sched: Move code around sched,dl: Fix sched class hopping CBS hole sched, dl: Convert switched_{from, to}_dl() / prio_changed_dl() to balance callbacks sched,dl: Remove return value from pull_dl_task() sched, rt: Convert switched_{from, to}_rt() / prio_changed_rt() to balance callbacks sched,rt: Remove return value from pull_rt_task() sched: Allow balance callbacks for check_class_changed() sched: Use replace normalize_task() with __sched_setscheduler() sched: Replace post_schedule with a balance callback list
| * sched,lockdep: Employ lock pinningPeter Zijlstra2015-06-195-8/+71
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Employ the new lockdep lock pinning annotation to ensure no 'accidental' lock-breaks happen with rq->lock. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124744.003233193@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * lockdep: Implement lock pinningPeter Zijlstra2015-06-192-0/+90
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a lockdep annotation that WARNs if you 'accidentially' unlock a lock. This is especially helpful for code with callbacks, where the upper layer assumes a lock remains taken but a lower layer thinks it maybe can drop and reacquire the lock. By unwittingly breaking up the lock, races can be introduced. Lock pinning is a lockdep annotation that helps with this, when you lockdep_pin_lock() a held lock, any unlock without a lockdep_unpin_lock() will produce a WARN. Think of this as a relative of lockdep_assert_held(), except you don't only assert its held now, but ensure it stays held until you release your assertion. RFC: a possible alternative API would be something like: int cookie = lockdep_pin_lock(&foo); ... lockdep_unpin_lock(&foo, cookie); Where we pick a random number for the pin_count; this makes it impossible to sneak a lock break in without also passing the right cookie along. I've not done this because it ends up generating code for !LOCKDEP, esp. if you need to pass the cookie around for some reason. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124743.906731065@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * lockdep: Simplify lock_release()Peter Zijlstra2015-06-191-101/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | lock_release() takes this nested argument that's mostly pointless these days, remove the implementation but leave the argument a rudiment for now. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124743.840411606@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched: Streamline the task migration locking a littlePeter Zijlstra2015-06-191-42/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The whole migrate_task{,s}() locking seems a little shaky, there's a lot of dropping an require happening. Pull the locking up into the callers as far as possible to streamline the lot. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124743.755256708@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched: Move code aroundPeter Zijlstra2015-06-191-186/+178
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation to reworking set_cpus_allowed_ptr() move some code around. This also removes some superfluous #ifdefs and adds comments to some #endifs. text data bss dec hex filename 12211532 1738144 1081344 15031020 e55aec defconfig-build/vmlinux.pre 12211532 1738144 1081344 15031020 e55aec defconfig-build/vmlinux.post Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124743.662086684@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched,dl: Fix sched class hopping CBS holePeter Zijlstra2015-06-191-66/+86
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We still have a few pending issues with the deadline code, one of which is that switching between scheduling classes can 'leak' CBS state. Close the hole by retaining the current CBS state when leaving SCHED_DEADLINE and unconditionally programming the deadline timer. The timer will then reset the CBS state if the task is still !SCHED_DEADLINE by the time it hits. If the task left SCHED_DEADLINE it will not call task_dead_dl() and we'll not cancel the hrtimer, leaving us a pending timer in free space. Avoid this by giving the timer a task reference, this avoids littering the task exit path for this rather uncommon case. In order to do this, I had to move dl_task_offline_migration() below the replenishment, such that the task_rq()->lock fully covers that. While doing this, I noticed that it (was) buggy in assuming a task is enqueued and or we need to enqueue the task now. Fixing this means select_task_rq_dl() might encounter an offline rq -- look into that. As a result this kills cancel_dl_timer() which included a rq->lock break. Fixes: 40767b0dc768 ("sched/deadline: Fix deadline parameter modification handling") Cc: Wanpeng Li <wanpeng.li@linux.intel.com> Cc: Luca Abeni <luca.abeni@unitn.it> Cc: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: Luca Abeni <luca.abeni@unitn.it> Cc: Juri Lelli <juri.lelli@arm.com> Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124743.574192138@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched, dl: Convert switched_{from, to}_dl() / prio_changed_dl() to balance ↵Peter Zijlstra2015-06-191-21/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | callbacks Remove the direct {push,pull} balancing operations from switched_{from,to}_dl() / prio_changed_dl() and use the balance callback queue. Again, err on the side of too many reschedules; since too few is a hard bug while too many is just annoying. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124742.968262663@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched,dl: Remove return value from pull_dl_task()Peter Zijlstra2015-06-191-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to be able to use pull_dl_task() from a callback, we need to do away with the return value. Since the return value indicates if we should reschedule, do this inside the function. Since not all callers currently do this, this can increase the number of reschedules due rt balancing. Too many reschedules is not a correctness issues, too few are. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124742.859398977@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched, rt: Convert switched_{from, to}_rt() / prio_changed_rt() to balance ↵Peter Zijlstra2015-06-191-16/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | callbacks Remove the direct {push,pull} balancing operations from switched_{from,to}_rt() / prio_changed_rt() and use the balance callback queue. Again, err on the side of too many reschedules; since too few is a hard bug while too many is just annoying. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124742.766832367@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched,rt: Remove return value from pull_rt_task()Peter Zijlstra2015-06-191-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to be able to use pull_rt_task() from a callback, we need to do away with the return value. Since the return value indicates if we should reschedule, do this inside the function. Since not all callers currently do this, this can increase the number of reschedules due rt balancing. Too many reschedules is not a correctness issues, too few are. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124742.679002000@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched: Allow balance callbacks for check_class_changed()Peter Zijlstra2015-06-191-3/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to remove dropping rq->lock from the switched_{to,from}()/prio_changed() sched_class methods, run the balance callbacks after it. We need to remove dropping rq->lock because its buggy, suppose using sched_setattr()/sched_setscheduler() to change a running task from FIFO to OTHER. By the time we get to switched_from_rt() the task is already enqueued on the cfs runqueues. If switched_from_rt() does pull_rt_task() and drops rq->lock, load-balancing can come in and move our task @p to another rq. The subsequent switched_to_fair() still assumes @p is on @rq and bad things will happen. By using balance callbacks we delay the load-balancing operations {rt,dl}x{push,pull} until we've done all the important work and the task is fully set up. Furthermore, the balance callbacks do not know about @p, therefore they cannot get confused like this. Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Link: http://lkml.kernel.org/r/20150611124742.615343911@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched: Use replace normalize_task() with __sched_setscheduler()Peter Zijlstra2015-06-191-42/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reduce duplicate logic; normalize_task() is a simplified version of __sched_setscheduler(). Parametrize the difference and collapse. This reduces the amount of check_class_changed() sites. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124742.532642391@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * sched: Replace post_schedule with a balance callback listPeter Zijlstra2015-06-194-38/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Generalize the post_schedule() stuff into a balance callback list. This allows us to more easily use it outside of schedule() and cross sched_class. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: ktkhai@parallels.com Cc: rostedt@goodmis.org Cc: juri.lelli@gmail.com Cc: pang.xunlei@linaro.org Cc: oleg@redhat.com Cc: wanpeng.li@linux.intel.com Cc: umgwanakikbuti@gmail.com Link: http://lkml.kernel.org/r/20150611124742.424032725@infradead.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * Merge branch 'timers/core' into sched/hrtimersThomas Gleixner2015-06-1974-1324/+2057
| |\ | | | | | | | | | | | | Merge sched/core and timers/core so we can apply the sched balancing patch queue, which depends on both.
* | \ Merge branch 'sched-locking-for-linus' of ↵Linus Torvalds2015-06-243-34/+88
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Thomas Gleixner: "These locking updates depend on the alreay merged sched/core branch: - Lockless top waiter wakeup for rtmutex (Davidlohr) - Reduce hash bucket lock contention for PI futexes (Sebastian) - Documentation update (Davidlohr)" * 'sched-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rtmutex: Update stale plist comments futex: Lower the lock contention on the HB lock during wake up locking/rtmutex: Implement lockless top-waiter wakeup
| * | | locking/rtmutex: Update stale plist commentsDavidlohr Bueso2015-06-191-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ... as of fb00aca4744 (rtmutex: Turn the plist into an rb-tree) we no longer use plists for queuing any waiters. Update stale comments. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1432056298-18738-4-git-send-email-dave@stgolabs.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | futex: Lower the lock contention on the HB lock during wake upSebastian Andrzej Siewior2015-06-193-18/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | wake_futex_pi() wakes the task before releasing the hash bucket lock (HB). The first thing the woken up task usually does is to acquire the lock which requires the HB lock. On SMP Systems this leads to blocking on the HB lock which is released by the owner shortly after. This patch rearranges the unlock path by first releasing the HB lock and then waking up the task. [ tglx: Fixed up the rtmutex unlock path ] Originally-from: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Link: http://lkml.kernel.org/r/20150617083350.GA2433@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | | locking/rtmutex: Implement lockless top-waiter wakeupDavidlohr Bueso2015-06-181-11/+10
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark the task for later wakeup after the wait_lock has been released. This way, once the next task is awoken, it will have a better chance to of finding the wait_lock free when continuing executing in __rt_mutex_slowlock() when trying to acquire the rtmutex, calling try_to_take_rt_mutex(). Upon contended scenarios, other tasks attempting take the lock may acquire it first, right after the wait_lock is released, but (a) this can also occur with the current code, as it relies on the spinlock fairness, and (b) we are dealing with the top-waiter anyway, so it will always take the lock next. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1432056298-18738-2-git-send-email-dave@stgolabs.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | Merge tag 'arm64-upstream' of ↵Linus Torvalds2015-06-2464-741/+938
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Mostly refactoring/clean-up: - CPU ops and PSCI (Power State Coordination Interface) refactoring following the merging of the arm64 ACPI support, together with handling of Trusted (secure) OS instances - Using fixmap for permanent FDT mapping, removing the initial dtb placement requirements (within 512MB from the start of the kernel image). This required moving the FDT self reservation out of the memreserve processing - Idmap (1:1 mapping used for MMU on/off) handling clean-up - Removing flush_cache_all() - not safe on ARM unless the MMU is off. Last stages of CPU power down/up are handled by firmware already - "Alternatives" (run-time code patching) refactoring and support for immediate branch patching, GICv3 CPU interface access - User faults handling clean-up And some fixes: - Fix for VDSO building with broken ELF toolchains - Fix another case of init_mm.pgd usage for user mappings (during ASID roll-over broadcasting) - Fix for FPSIMD reloading after CPU hotplug - Fix for missing syscall trace exit - Workaround for .inst asm bug - Compat fix for switching the user tls tpidr_el0 register" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (42 commits) arm64: use private ratelimit state along with show_unhandled_signals arm64: show unhandled SP/PC alignment faults arm64: vdso: work-around broken ELF toolchains in Makefile arm64: kernel: rename __cpu_suspend to keep it aligned with arm arm64: compat: print compat_sp instead of sp arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAP arm64: entry: fix context tracking for el0_sp_pc arm64: defconfig: enable memtest arm64: mm: remove reference to tlb.S from comment block arm64: Do not attempt to use init_mm in reset_context() arm64: KVM: Switch vgic save/restore to alternative_insn arm64: alternative: Introduce feature for GICv3 CPU interface arm64: psci: fix !CONFIG_HOTPLUG_CPU build warning arm64: fix bug for reloading FPSIMD state after CPU hotplug. arm64: kernel thread don't need to save fpsimd context. arm64: fix missing syscall trace exit arm64: alternative: Work around .inst assembler bugs arm64: alternative: Merge alternative-asm.h into alternative.h arm64: alternative: Allow immediate branch as alternative instruction arm64: Rework alternate sequence for ARM erratum 845719 ...
| * | | arm64: use private ratelimit state along with show_unhandled_signalsVladimir Murzin2015-06-193-5/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | printk_ratelimit() shares the ratelimiting state with other callers what may lead to scenarios where at the time we want to print out debug information we already limited, so nothing appears in the dmesg - this makes exception-trace quite poor helper in debugging. Additionally, we have imbalance with some messages limited with global ratelimit state and other messages limited with their private state defined via pr_*_ratelimited(). To address this inconsistency show_unhandled_signals_ratelimited() macro is introduced and caller sites are converted to use it. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: show unhandled SP/PC alignment faultsVladimir Murzin2015-06-191-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Report unhandled SP/PC alignment faults if the show_unhandled_signals variable is set (via /proc/sys/debug/exception-trace). Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: vdso: work-around broken ELF toolchains in MakefileWill Deacon2015-06-191-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building the kernel with a bare-metal (ELF) toolchain, the -shared option may not be passed down to collect2, resulting in silent corruption of the vDSO image (in particular, the DYNAMIC section is omitted). The effect of this corruption is that the dynamic linker fails to find the vDSO symbols and libc is instead used for the syscalls that we intended to optimise (e.g. gettimeofday). Functionally, there is no issue as the sigreturn trampoline is still intact and located by the kernel. This patch fixes the problem by explicitly passing -shared to the linker when building the vDSO. Cc: <stable@vger.kernel.org> Reported-by: Szabolcs Nagy <Szabolcs.Nagy@arm.com> Reported-by: James Greenlaigh <james.greenhalgh@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: kernel: rename __cpu_suspend to keep it aligned with armSudeep Holla2015-06-195-13/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch renames __cpu_suspend to cpu_suspend so that it's aligned with ARM32. It also removes the redundant wrapper created. This is in preparation to implement generic PSCI system suspend using the cpu_{suspend,resume} which now has the same interface on both ARM and ARM64. Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: compat: print compat_sp instead of spVladimir Murzin2015-06-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We check against compat_sp, but print out arm64's sp - fix it. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAPDave P Martin2015-06-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The memmap freeing code in free_unused_memmap() computes the end of each memblock by adding the memblock size onto the base. However, if SPARSEMEM is enabled then the value (start) used for the base may already have been rounded downwards to work out which memmap entries to free after the previous memblock. This may cause memmap entries that are in use to get freed. In general, you're not likely to hit this problem unless there are at least 2 memblocks and one of them is not aligned to a sparsemem section boundary. Note that carve-outs can increase the number of memblocks by splitting the regions listed in the device tree. This problem doesn't occur with SPARSEMEM_VMEMMAP, because the vmemmap code deals with freeing the unused regions of the memmap instead of requiring the arch code to do it. This patch gets the memblock base out of the memblock directly when computing the block end address to ensure the correct value is used. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: entry: fix context tracking for el0_sp_pcMark Rutland2015-06-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 6c81fe7925cc4c42 ("arm64: enable context tracking") did not update el0_sp_pc to use ct_user_exit, but this appears to have been unintentional. In commit 6ab6463aeb5fbc75 ("arm64: adjust el0_sync so that a function can be called") we made x0 available, and in the return to userspace we call ct_user_enter in the kernel_exit macro. Due to this, we currently don't correctly inform RCU of the user->kernel transition, and may erroneously account for time spent in the kernel as if we were in an extended quiescent state when CONFIG_CONTEXT_TRACKING is enabled. As we do record the kernel->user transition, a userspace application making accesses from an unaligned stack pointer can demonstrate the imbalance, provoking the following warning: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 3660 at kernel/context_tracking.c:75 context_tracking_enter+0xd8/0xe4() Modules linked in: CPU: 2 PID: 3660 Comm: a.out Not tainted 4.1.0-rc7+ #8 Hardware name: ARM Juno development board (r0) (DT) Call trace: [<ffffffc000089914>] dump_backtrace+0x0/0x124 [<ffffffc000089a48>] show_stack+0x10/0x1c [<ffffffc0005b3cbc>] dump_stack+0x84/0xc8 [<ffffffc0000b3214>] warn_slowpath_common+0x98/0xd0 [<ffffffc0000b330c>] warn_slowpath_null+0x14/0x20 [<ffffffc00013ada4>] context_tracking_enter+0xd4/0xe4 [<ffffffc0005b534c>] preempt_schedule_irq+0xd4/0x114 [<ffffffc00008561c>] el1_preempt+0x4/0x28 [<ffffffc0001b8040>] exit_files+0x38/0x4c [<ffffffc0000b5b94>] do_exit+0x430/0x978 [<ffffffc0000b614c>] do_group_exit+0x40/0xd4 [<ffffffc0000c0208>] get_signal+0x23c/0x4f4 [<ffffffc0000890b4>] do_signal+0x1ac/0x518 [<ffffffc000089650>] do_notify_resume+0x5c/0x68 ---[ end trace 963c192600337066 ]--- This patch adds the missing ct_user_exit to the el0_sp_pc entry path, correcting the context tracking for this case. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Fixes: 6c81fe7925cc ("arm64: enable context tracking") Cc: <stable@vger.kernel.org> # v3.17+ Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: defconfig: enable memtestMark Rutland2015-06-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel memtest utility is incredibly useful for detecting memory problems, but sadly isn't in defconfig. The memtest itself is only run when the user has explicitly passed a memtest option on the kernel command line, so simply enabling the option should not have a negative impact. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Vladimir Murzin <vladimir.murzin@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: mm: remove reference to tlb.S from comment blockVladimir Murzin2015-06-121-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tlb.S has been removed since fa48e6f "arm64: mm: Optimise tlb flush logic where we have >4K granule", so align comment with that. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: Do not attempt to use init_mm in reset_context()Catalin Marinas2015-06-121-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After secondary CPU boot or hotplug, the active_mm of the idle thread is &init_mm. The init_mm.pgd (swapper_pg_dir) is only meant for TTBR1_EL1 and must not be set in TTBR0_EL1. Since when active_mm == &init_mm the TTBR0_EL1 is already set to the reserved value, there is no need to perform any context reset. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: <stable@vger.kernel.org>
| * | | arm64: KVM: Switch vgic save/restore to alternative_insnMarc Zyngier2015-06-126-51/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So far, we configured the world-switch by having a small array of pointers to the save and restore functions, depending on the GIC used on the platform. Loading these values each time is a bit silly (they never change), and it makes sense to rely on the instruction patching instead. This leads to a nice cleanup of the code. Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: alternative: Introduce feature for GICv3 CPU interfaceMarc Zyngier2015-06-122-1/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a new item to the feature set (ARM64_HAS_SYSREG_GIC_CPUIF) to indicate that we have a system register GIC CPU interface This will help KVM switching to alternative instruction patching. Reviewed-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: psci: fix !CONFIG_HOTPLUG_CPU build warningWill Deacon2015-06-111-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building without CONFIG_HOTPLUG_CPU, GCC complains (rightly) that psci_tos_resident_on is unused: arch/arm64/kernel/psci.c:61:13: warning: ‘psci_tos_resident_on’ defined but not used [-Wunused-function] static bool psci_tos_resident_on(int cpu) As it's only ever used when CONFIG_HOTPLUG_CPU is selected, let's move it into the existing ifdef. Signed-off-by: Will Deacon <will.deacon@arm.com> [Mark: write commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: fix bug for reloading FPSIMD state after CPU hotplug.Janet Liu2015-06-111-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now FPSIMD don't handle HOTPLUG_CPU. This introduces bug after cpu down/up process. After cpu down/up process, the FPSMID hardware register is default value, not any process's fpsimd context. when CPU_DEAD set cpu's fpsimd_state to NULL, it will force to load the fpsimd context for the thread, to avoid the chance to skip to load the context. If process A is the last user process on CPU N before cpu down, and the first user process on the same CPU N after cpu up, A's fpsimd_state.cpu is the current cpu id, and per_cpu(fpsimd_last_state) points A's fpsimd_state, so kernel will not reload the context during it return to user space. Signed-off-by: Janet Liu <janet.liu@spreadtrum.com> Signed-off-by: Xiongshan An <xiongshan.an@spreadtrum.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com> [catalin.marinas@arm.com: some mostly cosmetic clean-ups] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: kernel thread don't need to save fpsimd context.Janet Liu2015-06-111-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernel thread's default fpsimd state is zero. When fork a thread, if parent is kernel thread, and save hardware context to parent's fpsimd state, but this hardware context is user process's context, because kernel thread don't use fpsimd, it will not introduce issue, it add a little cost. Signed-off-by: Janet Liu <janet.liu@spreadtrum.com> Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | arm64: fix missing syscall trace exitJosh Stone2015-06-081-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a syscall is entered without TIF_SYSCALL_TRACE set, then it goes on the fast path. It's then possible to have TIF_SYSCALL_TRACE added in the middle of the syscall, but ret_fast_syscall doesn't check this flag again. This causes a ptrace syscall-exit-stop to be missed. For instance, from a PTRACE_EVENT_FORK reported during do_fork, the tracer might resume with PTRACE_SYSCALL, setting TIF_SYSCALL_TRACE. Now the completion of the fork should have a syscall-exit-stop. Russell King fixed this on arm by re-checking _TIF_SYSCALL_WORK in the fast exit path. Do the same on arm64. Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Josh Stone <jistone@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | Merge branch 'arm64/psci-rework' of ↵Catalin Marinas2015-06-057-122/+175
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux * 'arm64/psci-rework' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux: arm64: psci: remove ACPI coupling arm64: psci: kill psci_power_state arm64: psci: account for Trusted OS instances arm64: psci: support unsigned return values arm64: psci: remove unnecessary id indirection arm64: smp: consistently use error codes arm64: smp_plat: add get_logical_index arm/arm64: kvm: add missing PSCI include Conflicts: arch/arm64/kernel/smp.c
| | * | | arm64: psci: remove ACPI couplingMark Rutland2015-05-274-18/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 32-bit ARM port doesn't have ACPI headers, and conditionally including them is going to look horrendous. In preparation for sharing the PSCI invocation code with 32-bit, move the acpi_psci_* function declarations and definitions such that the PSCI client code need not include ACPI headers. While it would seem like we could simply hide the ACPI includes in psci.h, the ACPI headers have hilarious circular dependencies which make this infeasible without reorganising most of ACPICA. So rather than doing that, move the acpi_psci_* prototypes into psci.h. The psci_acpi_init function is made dependent on CONFIG_ACPI (with a stub implementation in asm/psci.h) such that it need not be built for 32-bit ARM or kernels without ACPI support. The currently missing __init annotations are added to the prototypes in the header. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Al Stone <al.stone@linaro.org> Reviewed-by: Ashwin Chaugule <ashwin.chaugule@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Will Deacon <will.deacon@arm.com>
| | * | | arm64: psci: kill psci_power_stateMark Rutland2015-05-271-52/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A PSCI 1.0 implementation may choose to use the new extended StateID format, the presence of which may be queried via the PSCI_FEATURES call. The layout of this new StateID format is incompatible with the existing format, and so to handle both we must abstract attempts to parse the fields. In preparation for PSCI 1.0 support, this patch introduces psci_power_state_loses_context and psci_power_state_is_valid functions to query information from a PSCI power state, which is no longer decomposed (and hence the pack/unpack functions are removed). As it is no longer decomposed, it is now passed round as an opaque u32 token. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Will Deacon <will.deacon@arm.com>
| | * | | arm64: psci: account for Trusted OS instancesMark Rutland2015-05-271-0/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Software resident in the secure world (a "Trusted OS") may cause CPU_OFF calls for the CPU it is resident on to be denied. Such a denial would be fatal for the kernel, and so we must detect when this can happen before the point of no return. This patch implements Trusted OS detection for PSCI 0.2+ systems, using MIGRATE_INFO_TYPE and MIGRATE_INFO_UP_CPU. When a trusted OS is detected as resident on a particular CPU, attempts to hot unplug that CPU will be denied early, before they can prove fatal. Trusted OS migration is not implemented by this patch. Implementation of migratable UP trusted OSs seems unlikely, and the right policy for migration is unclear (and will likely differ across implementations). As such, it is likely that migration will require cooperation with Trusted OS drivers. PSCI implementations prior to 0.1 do not provide the facility to detect the presence of a Trusted OS, nor the CPU any such OS is resident on, so without additional information it is not possible to handle Trusted OSs with PSCI 0.1. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Will Deacon <will.deacon@arm.com>
| | * | | arm64: psci: support unsigned return valuesMark Rutland2015-05-271-29/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PSCI_VERSION and MIGRATE_INFO_TYPE_UP_CPU return unsigned values, with the latter returning a 64-bit value. However, the PSCI invocation functions have prototypes returning int. This patch upgrades the invocation functions to return unsigned long, with a new typedef to keep things legible. As PSCI_VERSION cannot return a negative value, the erroneous check against PSCI_RET_NOT_SUPPORTED is also removed. The unrelated psci_initcall_t typedef is moved closer to its first user, to avoid confusion with the invocation functions. In preparation for sharing the code with ARM, unsigned long is used in preference of u64. In the SMC32 calling convention, the relevant fields will be 32 bits wide. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Will Deacon <will.deacon@arm.com>
| | * | | arm64: psci: remove unnecessary id indirectionMark Rutland2015-05-271-17/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PSCI 0.1 did not define canonical IDs for CPU_ON, CPU_OFF, CPU_SUSPEND, or MIGRATE, and so these need to be provided when using firmware compliant to PSCI 0.1. However, functions introduced in 0.2 or later have canonical IDs, and these cannot be provided via DT. There's no need to indirect the IDs via a table; they can be used directly at callsites (and already are for SYSTEM_OFF and SYSTEM_RESET). This patch removes the unnecessary function ID indirection for AFFINITY_INFO and MIGRATE_INFO_TYPE. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Will Deacon <will.deacon@arm.com>
| | * | | arm64: smp: consistently use error codesMark Rutland2015-05-272-7/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cpu_kill currently returns one for success and zero for failure, which is unlike all the other cpu_operations, which return zero for success and an error code upon failure. This difference is unnecessarily confusing. Make cpu_kill consistent with the other cpu_operations. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Will Deacon <will.deacon@arm.com>
| | * | | arm64: smp_plat: add get_logical_indexMark Rutland2015-05-271-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PSCI MIGRATE_INFO_UP_CPU call returns a physical ID, which we will need to map back to a Linux logical ID. Implement a reusable get_logical_index to map from a physical ID to a logical ID. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Will Deacon <will.deacon@arm.com>
| | * | | arm/arm64: kvm: add missing PSCI includeMark Rutland2015-05-271-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We make use of the PSCI function IDs, but don't explicitly include the header which defines them. Relying on transitive header includes is fragile and will be broken as headers are refactored. This patch includes the relevant header file directly so as to avoid future breakage. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com>
| * | | | arm64: alternative: Work around .inst assembler bugsMarc Zyngier2015-06-051-7/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | AArch64 toolchains suffer from the following bug: $ cat blah.S 1: .inst 0x01020304 .if ((. - 1b) != 4) .error "blah" .endif $ aarch64-linux-gnu-gcc -c blah.S blah.S: Assembler messages: blah.S:3: Error: non-constant expression in ".if" statement which precludes the use of msr_s and co as part of alternatives. We workaround this issue by not directly testing the labels themselves, but by moving the current output pointer by a value that should always be zero. If this value is not null, then we will trigger a backward move, which is expclicitely forbidden. This triggers the error we're after: AS arch/arm64/kvm/hyp.o arch/arm64/kvm/hyp.S: Assembler messages: arch/arm64/kvm/hyp.S:1377: Error: attempt to move .org backwards scripts/Makefile.build:294: recipe for target 'arch/arm64/kvm/hyp.o' failed make[1]: *** [arch/arm64/kvm/hyp.o] Error 1 Makefile:946: recipe for target 'arch/arm64/kvm' failed Not pretty, but at least works on the current toolchains. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: alternative: Merge alternative-asm.h into alternative.hMarc Zyngier2015-06-054-31/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | asm/alternative-asm.h and asm/alternative.h are extremely similar, and really deserve to live in the same file (as this makes further modufications a bit easier). Fold the content of alternative-asm.h into alternative.h, and update the few users. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: alternative: Allow immediate branch as alternative instructionMarc Zyngier2015-06-051-5/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since all branches are PC-relative on AArch64, these instructions cannot be used as an alternative with the simplistic approach we currently have (the immediate has been computed from the .altinstr_replacement section, and end-up being completely off if the target is outside of the replacement sequence). This patch handles the branch instructions in a different way, using the insn framework to recompute the immediate, and generate the right displacement in the above case. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: Rework alternate sequence for ARM erratum 845719Marc Zyngier2015-06-051-12/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The workaround for erratum 845719 is currently using a branch between two alternate sequences, which is quite fragile, and that we are going to break as we rework the alternative code. This patch reworks the workaround to fit in a single alternative sequence. The generated code itself is unchanged. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| * | | | arm64: insn: Add aarch64_{get,set}_branch_offsetMarc Zyngier2015-06-032-0/+63
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to deal with branches located in alternate sequences, but pointing to the main kernel text, it is required to extract the relative displacement encoded in the instruction, and to be able to update said instruction with a new offset (once it is known). For this, we introduce three new helpers: - aarch64_insn_is_branch_imm is a predicate indicating if the instruction is an immediate branch - aarch64_get_branch_offset returns a signed value representing the byte offset encoded in a branch instruction - aarch64_set_branch_offset takes an instruction and an offset, and returns the corresponding updated instruction. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>