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2014-07-09cpuset: add cs->effective_cpus and cs->effective_memsLi Zefan
We're going to have separate user-configured masks and effective ones. Eventually configured masks can only be changed by writing cpuset.cpus and cpuset.mems, and they won't be restricted by parent cpuset. While effective masks reflect cpu/memory hotplug and hierachical restriction, and these are the real masks that apply to the tasks in the cpuset. We calculate effective mask this way: - top cpuset's effective_mask == online_mask, otherwise - cpuset's effective_mask == configured_mask & parent effective_mask, if the result is empty, it inherits parent effective mask. Those behavior changes are for default hierarchy only. For legacy hierachy, effective_mask and configured_mask are the same, so we won't break old interfaces. This patch adds the effective masks to struct cpuset and initializes them. The effective masks of the top cpuset is the same with configured masks, and a child cpuset inherits its parent's effective masks. This won't introduce behavior change. v2: - s/real_{mems,cpus}_allowed/effective_{mems,cpus}, suggested by Tejun. - don't init effective masks in cpuset_css_online() if !cgroup_on_dfl. Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-07-09Merge tag 'usb-serial-3.16-rc5' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-linus Johan writes: USB-serial fixes for v3.16-rc5 Here are some USB-serial updates for v3.16-rc5 that add two new device IDs. Signed-off-by: Johan Hovold <johan@kernel.org>
2014-07-09Merge tag 'f2fs-fixes-3.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs bugfixes from Jaegeuk Kim: "This includes a couple of bug fixes found by xfstests. In addition, one critical bug was reported by Brian Chadwick, which is falling into the infinite loop in balance_dirty_pages. And it turned out due to the IO merging policy in f2fs, which was newly merged in 3.16. - fix normal and recovery path for fallocated regions - fix error case mishandling - recover renamed fsync inodes correctly - fix to get out of infinite loops in balance_dirty_pages - fix kernel NULL pointer error" * tag 'f2fs-fixes-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: f2fs: avoid to access NULL pointer in issue_flush_thread f2fs: check bdi->dirty_exceeded when trying to skip data writes f2fs: do checkpoint for the renamed inode f2fs: release new entry page correctly in error path of f2fs_rename f2fs: fix error path in init_inode_metadata f2fs: check lower bound nid value in check_nid_range f2fs: remove unused variables in f2fs_sm_info f2fs: fix not to allocate unnecessary blocks during fallocate f2fs: recover fallocated data and its i_size together f2fs: fix to report newly allocate region as extent
2014-07-09Merge branches 'doc.2014.07.08a', 'fixes.2014.07.09a', ↵Paul E. McKenney
'maintainers.2014.07.08b', 'nocbs.2014.07.07a' and 'torture.2014.07.07a' into HEAD doc.2014.07.08a: Documentation updates. fixes.2014.07.09a: Miscellaneous fixes. maintainers.2014.07.08b: Maintainership updates. nocbs.2014.07.07a: Callback-offloading fixes. torture.2014.07.07a: Torture-test updates.
2014-07-09rcu: Fix a sparse warning in rcu_report_unblock_qs_rnp()Pranith Kumar
This commit annotates rcu_report_unblock_qs_rnp() in order to fix the following sparse warning: kernel/rcu/tree_plugin.h:990:13: warning: context imbalance in 'rcu_report_unblock_qs_rnp' - unexpected unlock Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Fix a sparse warning in rcu_initiate_boost()Pranith Kumar
This commit annotates rcu_initiate_boost() fixes the following sparse warning: kernel/rcu/tree_plugin.h:1494:13: warning: context imbalance in 'rcu_initiate_boost' - unexpected unlock Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Fix __rcu_reclaim() to use true/false for boolPaul E. McKenney
The __rcu_reclaim() function returned 0/1, which is not proper for a function of type bool. This commit therefore converts to false/true. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Remove CONFIG_PROVE_RCU_DELAYPaul E. McKenney
The CONFIG_PROVE_RCU_DELAY Kconfig parameter doesn't appear to be very effective at finding race conditions, so this commit removes it. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> [ paulmck: Remove definition and uses as noted by Paul Bolle. ]
2014-07-09rcu: Use __this_cpu_read() instead of per_cpu_ptr()Shan Wei
The __this_cpu_read() function produces better code than does per_cpu_ptr() on both ARM and x86. For example, gcc (Ubuntu/Linaro 4.7.3-12ubuntu1) 4.7.3 produces the following: ARMv7 per_cpu_ptr(): force_quiescent_state: mov r3, sp @, bic r1, r3, #8128 @ tmp171,, ldr r2, .L98 @ tmp169, bic r1, r1, #63 @ tmp170, tmp171, ldr r3, [r0, #220] @ __ptr, rsp_6(D)->rda ldr r1, [r1, #20] @ D.35903_68->cpu, D.35903_68->cpu mov r6, r0 @ rsp, rsp ldr r2, [r2, r1, asl #2] @ tmp173, __per_cpu_offset add r3, r3, r2 @ tmp175, __ptr, tmp173 ldr r5, [r3, #12] @ rnp_old, D.29162_13->mynode ARMv7 __this_cpu_read(): force_quiescent_state: ldr r3, [r0, #220] @ rsp_7(D)->rda, rsp_7(D)->rda mov r6, r0 @ rsp, rsp add r3, r3, #12 @ __ptr, rsp_7(D)->rda, ldr r5, [r2, r3] @ rnp_old, *D.29176_13 Using gcc 4.8.2: x86_64 per_cpu_ptr(): movl %gs:cpu_number,%edx # cpu_number, pscr_ret__ movslq %edx, %rdx # pscr_ret__, pscr_ret__ movq __per_cpu_offset(,%rdx,8), %rdx # __per_cpu_offset, tmp93 movq %rdi, %r13 # rsp, rsp movq 1000(%rdi), %rax # rsp_9(D)->rda, __ptr movq 24(%rdx,%rax), %r12 # _15->mynode, rnp_old x86_64 __this_cpu_read(): movq %rdi, %r13 # rsp, rsp movq 1000(%rdi), %rax # rsp_9(D)->rda, rsp_9(D)->rda movq %gs:24(%rax),%r12 # _10->mynode, rnp_old Because this change produces significant benefits for these two very diverse architectures, this commit makes this change. Signed-off-by: Shan Wei <davidshan@tencent.com> Acked-by: Christoph Lameter <cl@linux.com> Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Don't use NMIs to dump other CPUs' stacksPaul E. McKenney
Although NMI-based stack dumps are in principle more accurate, they are also more likely to trigger deadlocks. This commit therefore replaces all uses of trigger_all_cpu_backtrace() with rcu_dump_cpu_stacks(), so that the CPU detecting an RCU CPU stall does the stack dumping. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Bind grace-period kthreads to non-NO_HZ_FULL CPUsPaul E. McKenney
Binding the grace-period kthreads to the timekeeping CPU resulted in significant performance decreases for some workloads. For more detail, see: https://lkml.org/lkml/2014/6/3/395 for benchmark numbers https://lkml.org/lkml/2014/6/4/218 for CPU statistics It turns out that it is necessary to bind the grace-period kthreads to the timekeeping CPU only when all but CPU 0 is a nohz_full CPU on the one hand or if CONFIG_NO_HZ_FULL_SYSIDLE=y on the other. In other cases, it suffices to bind the grace-period kthreads to the set of non-nohz_full CPUs. This commit therefore creates a tick_nohz_not_full_mask that is the complement of tick_nohz_full_mask, and then binds the grace-period kthread to the set of CPUs indicated by this new mask, which covers the CONFIG_NO_HZ_FULL_SYSIDLE=n case. The CONFIG_NO_HZ_FULL_SYSIDLE=y case still binds the grace-period kthreads to the timekeeping CPU. This commit also includes the tick_nohz_full_enabled() check suggested by Frederic Weisbecker. Reported-by: Jet Chen <jet.chen@intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [ paulmck: Created housekeeping_affine() and housekeeping_mask per fweisbec feedback. ]
2014-07-09rcu: Simplify priority boosting by putting rt_mutex in rcu_nodePaul E. McKenney
RCU priority boosting currently checks for boosting via a pointer in task_struct. However, this is not needed: As Oleg noted, if the rt_mutex is placed in the rcu_node instead of on the booster's stack, the boostee can simply check it see if it owns the lock. This commit makes this change, shrinking task_struct by one pointer and the kernel by thirteen lines. Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09rcu: Check both root and current rcu_node when setting up future grace periodPranith Kumar
The rcu_start_future_gp() function checks the current rcu_node's ->gpnum and ->completed twice, once without ACCESS_ONCE() and once with it. Which is pointless because we hold that rcu_node's ->lock at that point. The intent was to check the current rcu_node structure and the root rcu_node structure, the latter locklessly with ACCESS_ONCE(). This commit therefore makes that change. The reason that it is safe to locklessly check the root rcu_nodes's ->gpnum and ->completed fields is that we hold the current rcu_node's ->lock, which constrains the root rcu_node's ability to change its ->gpnum and ->completed fields. Of course, if there is a single rcu_node structure, then rnp_root==rnp, and holding the lock prevents all changes. If there is more than one rcu_node structure, then the code updates the fields in the following order: 1. Increment rnp_root->gpnum to start new grace period. 2. Increment rnp->gpnum to initialize the current rcu_node, continuing initialization for the new grace period. 3. Increment rnp_root->completed to end the current grace period. 4. Increment rnp->completed to continue cleaning up after the old grace period. So there are four possible combinations of relative values of these four fields: N N N N: RCU idle, new grace period must be initiated. Although rnp_root->gpnum might be incremented immediately after we check, that will just result in unnecessary work. The grace period already started, and we try to start it. N+1 N N N: RCU grace period just started. No further change is possible because we hold rnp->lock, so the checks of rnp_root->gpnum and rnp_root->completed are stable. We know that our request for a future grace period will be seen during grace-period cleanup. N+1 N N+1 N: RCU grace period is ongoing. Because rnp->gpnum is different than rnp->completed, we won't even look at rnp_root->gpnum and rnp_root->completed, so the possible concurrent change to rnp_root->completed does not matter. We know that our request for a future grace period will be seen during grace-period cleanup, which cannot pass this rcu_node because we hold its ->lock. N+1 N+1 N+1 N: RCU grace period has ended, but not yet been cleaned up. Because rnp->gpnum is different than rnp->completed, we won't look at rnp_root->gpnum and rnp_root->completed, so the possible concurrent change to rnp_root->completed does not matter. We know that our request for a future grace period will be seen during grace-period cleanup, which cannot pass this rcu_node because we hold its ->lock. Therefore, despite initial appearances, the lockless check is safe. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> [ paulmck: Update comment to say why the lockless check is safe. ] Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09rcu: Allow post-unlock reference for rt_mutexPaul E. McKenney
The current approach to RCU priority boosting uses an rt_mutex strictly for its priority-boosting side effects. The rt_mutex_init_proxy_locked() function is used by the booster to initialize the lock as held by the boostee. The booster then uses rt_mutex_lock() to acquire this rt_mutex, which priority-boosts the boostee. When the boostee reaches the end of its outermost RCU read-side critical section, it checks a field in its task structure to see whether it has been boosted, and, if so, uses rt_mutex_unlock() to release the rt_mutex. The booster can then go on to boost the next task that is blocking the current RCU grace period. But reasonable implementations of rt_mutex_unlock() might result in the boostee referencing the rt_mutex's data after releasing it. But the booster might have re-initialized the rt_mutex between the time that the boostee released it and the time that it later referenced it. This is clearly asking for trouble, so this commit introduces a completion that forces the booster to wait until the boostee has completely finished with the rt_mutex, thus avoiding the case where the booster is re-initializing the rt_mutex before the last boostee's last reference to that rt_mutex. This of course does introduce some overhead, but the priority-boosting code paths are miles from any possible fastpath, and the overhead of executing the completion will normally be quite small compared to the overhead of priority boosting and deboosting, so this should be OK. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09rcu: Loosen __call_rcu()'s rcu_head alignment constraintPaul E. McKenney
The m68k architecture aligns only to 16-bit boundaries, which can cause the align-to-32-bits check in __call_rcu() to trigger. Because there is currently no known potential need for more than one low-order bit, this commit loosens the check to 16-bit boundaries. Reported-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Eliminate read-modify-write ACCESS_ONCE() callsPaul E. McKenney
RCU contains code of the following forms: ACCESS_ONCE(x)++; ACCESS_ONCE(x) += y; ACCESS_ONCE(x) -= y; Now these constructs do operate correctly, but they really result in a pair of volatile accesses, one to do the load and another to do the store. This can be confusing, as the casual reader might well assume that (for example) gcc might generate a memory-to-memory add instruction for each of these three cases. In fact, gcc will do no such thing. Also, there is a good chance that the kernel will move to separate load and store variants of ACCESS_ONCE(), and constructs like the above could easily confuse both people and scripts attempting to make that sort of change. Finally, most of RCU's read-modify-write uses of ACCESS_ONCE() really only need the store to be volatile, so that the read-modify-write form might be misleading. This commit therefore changes the above forms in RCU so that each instance of ACCESS_ONCE() either does a load or a store, but not both. In a few cases, ACCESS_ONCE() was not critical, for example, for maintaining statisitics. In these cases, ACCESS_ONCE() has been dispensed with entirely. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09rcu: Remove redundant ACCESS_ONCE() from tick_do_timer_cpuPaul E. McKenney
In kernels built with CONFIG_NO_HZ_FULL, tick_do_timer_cpu is constant once boot completes. Thus, there is no need to wrap it in ACCESS_ONCE() in code that is built only when CONFIG_NO_HZ_FULL. This commit therefore removes the redundant ACCESS_ONCE(). Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Make rcu node arrays static const char * constFabian Frederick
Those two arrays are being passed to lockdep_init_map(), which expects const char *, and are stored in lockdep_map the same way. Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2014-07-09signal: Explain local_irq_save() callPaul E. McKenney
The explicit local_irq_save() in __lock_task_sighand() is needed to avoid a potential deadlock condition, as noted in a841796f11c90d53 (signal: align __lock_task_sighand() irq disabling and RCU). However, someone reading the code might be forgiven for concluding that this separate local_irq_save() was completely unnecessary. This commit therefore adds a comment referencing the shiny new block comment on rcu_read_unlock(). Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Handle obsolete references to TINY_PREEMPT_RCUPaul E. McKenney
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09rcu: Document deadlock-avoidance information for rcu_read_unlock()Paul E. McKenney
Reported-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2014-07-09KVM: MIPS: Document MIPS specifics of KVM API.James Hogan
Document the MIPS specific parts of the KVM API, including: - The layout of the kvm_regs structure. - The interrupt number passed to KVM_INTERRUPT. - The registers supported by the KVM_{GET,SET}_ONE_REG interface, and the encoding of those register ids. - That KVM_INTERRUPT and KVM_GET_REG_LIST are supported on MIPS. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: Reformat KVM_SET_ONE_REG register documentationJames Hogan
Some of the MIPS registers that can be accessed with the KVM_{GET,SET}_ONE_REG interface have fairly long names, so widen the Register column of the table in the KVM_SET_ONE_REG documentation to allow them to fit. Tabs in the table are replaced with spaces at the same time for consistency. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: Document KVM_SET_SIGNAL_MASK as universalJames Hogan
KVM_SET_SIGNAL_MASK is implemented in generic code and isn't x86 specific, so document it as being applicable for all architectures. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Cc: kvm@vger.kernel.org Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: x86: Fix lapic.c debug printsNadav Amit
In two cases lapic.c does not use the apic_debug macro correctly. This patch fixes them. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: x86: fix TSC matchingTomasz Grabiec
I've observed kvmclock being marked as unstable on a modern single-socket system with a stable TSC and qemu-1.6.2 or qemu-2.0.0. The culprit was failure in TSC matching because of overflow of kvm_arch::nr_vcpus_matched_tsc in case there were multiple TSC writes in a single synchronization cycle. Turns out that qemu does multiple TSC writes during init, below is the evidence of that (qemu-2.0.0): The first one: 0xffffffffa08ff2b4 : vmx_write_tsc_offset+0xa4/0xb0 [kvm_intel] 0xffffffffa04c9c05 : kvm_write_tsc+0x1a5/0x360 [kvm] 0xffffffffa04cfd6b : kvm_arch_vcpu_postcreate+0x4b/0x80 [kvm] 0xffffffffa04b8188 : kvm_vm_ioctl+0x418/0x750 [kvm] The second one: 0xffffffffa08ff2b4 : vmx_write_tsc_offset+0xa4/0xb0 [kvm_intel] 0xffffffffa04c9c05 : kvm_write_tsc+0x1a5/0x360 [kvm] 0xffffffffa090610d : vmx_set_msr+0x29d/0x350 [kvm_intel] 0xffffffffa04be83b : do_set_msr+0x3b/0x60 [kvm] 0xffffffffa04c10a8 : msr_io+0xc8/0x160 [kvm] 0xffffffffa04caeb6 : kvm_arch_vcpu_ioctl+0xc86/0x1060 [kvm] 0xffffffffa04b6797 : kvm_vcpu_ioctl+0xc7/0x5a0 [kvm] #0 kvm_vcpu_ioctl at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1780 #1 kvm_put_msrs at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1270 #2 kvm_arch_put_registers at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1909 #3 kvm_cpu_synchronize_post_init at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1641 #4 cpu_synchronize_post_init at /build/buildd/qemu-2.0.0+dfsg/include/sysemu/kvm.h:330 #5 cpu_synchronize_all_post_init () at /build/buildd/qemu-2.0.0+dfsg/cpus.c:521 #6 main at /build/buildd/qemu-2.0.0+dfsg/vl.c:4390 The third one: 0xffffffffa08ff2b4 : vmx_write_tsc_offset+0xa4/0xb0 [kvm_intel] 0xffffffffa04c9c05 : kvm_write_tsc+0x1a5/0x360 [kvm] 0xffffffffa090610d : vmx_set_msr+0x29d/0x350 [kvm_intel] 0xffffffffa04be83b : do_set_msr+0x3b/0x60 [kvm] 0xffffffffa04c10a8 : msr_io+0xc8/0x160 [kvm] 0xffffffffa04caeb6 : kvm_arch_vcpu_ioctl+0xc86/0x1060 [kvm] 0xffffffffa04b6797 : kvm_vcpu_ioctl+0xc7/0x5a0 [kvm] #0 kvm_vcpu_ioctl at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1780 #1 kvm_put_msrs at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1270 #2 kvm_arch_put_registers at /build/buildd/qemu-2.0.0+dfsg/target-i386/kvm.c:1909 #3 kvm_cpu_synchronize_post_reset at /build/buildd/qemu-2.0.0+dfsg/kvm-all.c:1635 #4 cpu_synchronize_post_reset at /build/buildd/qemu-2.0.0+dfsg/include/sysemu/kvm.h:323 #5 cpu_synchronize_all_post_reset () at /build/buildd/qemu-2.0.0+dfsg/cpus.c:512 #6 main at /build/buildd/qemu-2.0.0+dfsg/vl.c:4482 The fix is to count each vCPU only once when matched, so that nr_vcpus_matched_tsc holds the size of the matched set. This is achieved by reusing generation counters. Every vCPU with this_tsc_generation == cur_tsc_generation is in the matched set. The match set is cleared by setting cur_tsc_generation to a value which no other vCPU is set to (by incrementing it). I needed to bump up the counter size form u8 to u64 to ensure it never overflows. Otherwise in cases TSC is not written the same number of times on each vCPU the counter could overflow and incorrectly indicate some vCPUs as being in the matched set. This scenario seems unlikely but I'm not sure if it can be disregarded. Signed-off-by: Tomasz Grabiec <tgrabiec@cloudius-systems.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: nSVM: Set correct port for IOIO interception evaluationJan Kiszka
Obtaining the port number from DX is bogus as a) there are immediate port accesses and b) user space may have changed the register content while processing the PIO access. Forward the correct value from the instruction emulator instead. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: nSVM: Fix IOIO size reported on emulationJan Kiszka
The access size of an in/ins is reported in dst_bytes, and that of out/outs in src_bytes. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: nSVM: Fix IOIO bitmap evaluationJan Kiszka
First, kvm_read_guest returns 0 on success. And then we need to take the access size into account when testing the bitmap: intercept if any of bits corresponding to the access is set. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09KVM: nSVM: Do not report CLTS via SVM_EXIT_WRITE_CR0 to L1Jan Kiszka
CLTS only changes TS which is not monitored by selected CR0 interception. So skip any attempt to translate WRITE_CR0 to CR0_SEL_WRITE for this instruction. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-09Merge branch 'trace/ftrace/urgent' into trace/ftrace/coreSteven Rostedt (Red Hat)
Needed 099ed151675c "tracing: Remove ftrace_stop/start() from reading the trace file" for the removal of ftrace_start/stop().
2014-07-09cgroup: clean up sane_behavior handlingTejun Heo
After the previous patch to remove sane_behavior support from non-default hierarchies, CGRP_ROOT_SANE_BEHAVIOR is used only to indicate the default hierarchy while parsing mount options. This patch makes the following cleanups around it. * Don't show it in the mount option. Eventually the default hierarchy will be assigned a different filesystem type. * As sane_behavior is no longer effective on non-default hierarchies and the default hierarchy doesn't accept any mount options, parse_cgroupfs_options() can consider sane_behavior mount option as indicating the default hierarchy and fail if any other options are specified with it. While at it, remove one of the double blank lines in the function. * cgroup_mount() can now simply test CGRP_ROOT_SANE_BEHAVIOR to tell whether to mount the default hierarchy or not. * As CGROUP_ROOT_SANE_BEHAVIOR's only role now is indicating whether to select the default hierarchy or not during mount, it doesn't need to be set in the default hierarchy itself. cgroup_init_early() updated accordingly. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2014-07-09cgroup: remove sane_behavior support on non-default hierarchiesTejun Heo
sane_behavior has been used as a development vehicle for the default unified hierarchy. Now that the default hierarchy is in place, the flag became redundant and confusing as its usage is allowed on all hierarchies. There are gonna be either the default hierarchy or legacy ones. Let's make that clear by removing sane_behavior support on non-default hierarchies. This patch replaces cgroup_sane_behavior() with cgroup_on_dfl(). The comment on top of CGRP_ROOT_SANE_BEHAVIOR is moved to on top of cgroup_on_dfl() with sane_behavior specific part dropped. On the default and legacy hierarchies w/o sane_behavior, this shouldn't cause any behavior differences. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz>
2014-07-09cgroup: make interface file "cgroup.sane_behavior" legacy-onlyTejun Heo
"cgroup.sane_behavior" is added to help distinguishing whether sane_behavior is in effect or not. We now have the default hierarchy where the flag is always in effect and are planning to remove supporting sane behavior on the legacy hierarchies making this file on the default hierarchy rather pointless. Let's make it legacy only and thus always zero. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2014-07-09cgroup: remove CGRP_ROOT_OPTION_MASKTejun Heo
cgroup_root->flags only contains CGRP_ROOT_* flags and there's no reason to mask the flags. Remove CGRP_ROOT_OPTION_MASK. This doesn't cause any behavior differences. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2014-07-09firmware: Create directories for external firmwareMichal Marek
Commit 5180d5f4 ("firmware: Simplify directory creation") broke including firmware specified in CONFIG_EXTRA_FIRMWARE: MK_FW firmware/amd-ucode/microcode_amd.bin.gen.S /bin/sh: firmware/amd-ucode/microcode_amd.bin.gen.S: No such file or directory ... firmware/Makefile:185: recipe for target 'firmware/amd-ucode/microcode_amd.bin.gen.S' failed It works with O= builds, because the directory is created by Makefile.build. Create the directory in firmware/Makefile in non-O builds. Reported-and-tested-by: Ronald Uitermark <ronald645@gmail.com> Reported-and-tested-by: Torsten Kaiser <just.for.lkml@googlemail.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-07-09f2fs: avoid to access NULL pointer in issue_flush_threadChao Yu
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=75861 Denis 2014-05-10 11:28:59 UTC reported: "F2FS-fs (mmcblk0p28): mounting.. Unable to handle kernel NULL pointer dereference at virtual address 00000018 ... [<c0a2f678>] (_raw_spin_lock+0x3c/0x70) from [<c03a0330>] (issue_flush_thread+0x50/0x17c) [<c03a0330>] (issue_flush_thread+0x50/0x17c) from [<c01b4064>] (kthread+0x98/0xa4) [<c01b4064>] (kthread+0x98/0xa4) from [<c0108060>] (kernel_thread_exit+0x0/0x8)" This patch assign cmd_control_info in sm_info before issue_flush_thread is being created, so this make sure that issue flush thread will have no chance to access invalid info in fcc. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: check bdi->dirty_exceeded when trying to skip data writesJaegeuk Kim
If we don't check the current backing device status, balance_dirty_pages can fall into infinite pausing routine. This can be occurred when a lot of directories make a small number of dirty dentry pages including files. Reported-by: Brian Chadwick <brianchad@westnet.com.au> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: do checkpoint for the renamed inodeJaegeuk Kim
If an inode is renamed, it should be registered as file_lost_pino to conduct checkpoint at f2fs_sync_file. Otherwise, the inode cannot be recovered due to no dent_mark in the following scenario. Note that, this scenario is from xfstests/322. 1. create "a" 2. fsync "a" 3. rename "a" to "b" 4. fsync "b" 5. Sudden power-cut After recovery is done, "b" should be seen. However, the result shows "a", since the recovery procedure does not enter recover_dentry due to no dent_mark. The reason is like below. - The nid of "a" is checkpointed during #2, f2fs_sync_file. - The inode page for "b" produced by #3 is written without dent_mark by sync_node_pages. So, this patch fixes this bug by assinging file_lost_pino to the "a"'s inode. If the pino is lost, f2fs_sync_file conducts checkpoint, and then recovers the latest pino and its dentry information for further recovery. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: release new entry page correctly in error path of f2fs_renameChao Yu
This patch correct releasing code of new_page to avoid BUG_ON in error patch of f2fs_rename. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: fix error path in init_inode_metadataChao Yu
If we fail in this path: ->init_inode_metadata ->make_empty_dir ->get_new_data_page ->grab_cache_page return -ENOMEM We will bug on in error path of init_inode_metadata when call remove_inode_page because i_block = 2 (one inode block will be released later & one dentry block). We should release the dentry block in init_inode_metadata to avoid this BUG_ON, and avoid leak of dentry block resource, because we never have second chance to release that block in ->evict_inode as in upper error path we make this inode 'bad'. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: check lower bound nid value in check_nid_rangeChao Yu
This patch add lower bound verification for nid in check_nid_range, so nids reserved like 0, node, meta passed by caller could be checked there. And then check_nid_range could be used in f2fs_nfs_get_inode for simplifying code. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: remove unused variables in f2fs_sm_infoChao Yu
Remove unused variables in struct f2fs_sm_info. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09ACPI / PNP: add soc_button_array device ID to PNP IDs listZhang Rui
The soc_button_array PNP driver was introduced in 3.15. But in commit eec15edbb0e1 (ACPI / PNP: use device ID list for PNPACPI device enumeration), when reworking the PNPACPI device enumeration, we missed the soc_button_array device ID. This results in a regression in 3.16-rc1 that soc_button_array pnp device fails to be enumerated. Fix the problem by adding soc_button_array device ID into the acpi_pnp scan handler's ID list. Fixes: eec15edbb0e1 (ACPI / PNP: use device ID list for PNPACPI device enumeration) Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-07-09arm64: Add CONFIG_CC_STACKPROTECTORLaura Abbott
arm64 currently lacks support for -fstack-protector. Add similar functionality to arm to detect stack corruption. Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-09arm64: topology: add MPIDR-based detectionZi Shen Lim
Create cpu topology based on MPIDR. When hardware sets MPIDR to sane values, this method will always work. Therefore it should also work well as the fallback method. [1] When we have multiple processing elements in the system, we create the cpu topology by mapping each affinity level (from lowest to highest) to threads (if they exist), cores, and clusters. [1] http://www.spinics.net/lists/arm-kernel/msg317445.html Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Zi Shen Lim <zlim@broadcom.com> Signed-off-by: Mark Brown <broonie@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-09drm/i915/vlv: T12 eDP panel timing enforcement during rebootClint Taylor
The panel power sequencer on vlv doesn't appear to accept changes to its T12 power down duration during warm reboots. This change forces a delay for warm reboots to the T12 panel timing as defined in the VBT table for the connected panel. Ver2: removed redundant pr_crit(), commented magic value for pp_div_reg Ver3: moved SYS_RESTART check earlier, new name for pp_div. Ver4: Minor issue changes Ver5: Move registration of reboot notifier to edp_connector_init, Added warning comment to handler about lack of PM notification. Signed-off-by: Clint Taylor <clinton.a.taylor@intel.com> Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-09drm/i915: Only unbind vgacon, not other console driversDaniel Vetter
The console subsystem only provides a function to switch to a given console, but we want to actually only switach away from vgacon. Unconditionally switching to the dummy console resulted in switching away from fbcon in multi-gpu setups when other gpu drivers are loaded before i915. Then either the reinitialization of fbcon when i915 registers its fbdev emulation or the teardown of the fbcon driver killed the machine. So only switch to the dummy console when it's required. Kudos to Chris for the original idea, I've only refined it a bit to still unregister vgacon even when it's currently unused. This regression has been introduced in commit a4de05268e674e8ed31df6348269e22d6c6a1803 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Thu Jun 5 16:20:46 2014 +0200 drm/i915: Kick out vga console Reported-and-tested-by: Ed Tomlinson <edt@aei.ca> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: David Herrmann <dh.herrmann@gmail.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-09drm/i915: Don't clobber the GTT when it's within stolen memoryVille Syrjälä
On most gen2-4 platforms the GTT can be (or maybe always is?) inside the stolen memory region. If that's the case, reduce the size of the stolen memory appropriately to make make sure we don't clobber the GTT. v2: Deal with gen4 36 bit physical address Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=80151 Acked-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-07-09drm/i915/vlv: Update the DSI ULPS entry/exit sequenceShobhit Kumar
We should keep DEVICE_READY bit set in the ULPS enter sequence. In exit sequence also we should set DEVICE_READY, but thats causing blankout for me. Also exit sequence is simplified as per hw team recommendation. This should fix - [drm:intel_dsi_clear_device_ready] *ERROR* DSI LP not going Low Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=80818 Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com> Tested-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Jani Nikula <jani.nikula@intel.com>