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2019-07-24Documentation: move Documentation/virtual to Documentation/virtChristoph Hellwig1-215/+0
Renaming docs seems to be en vogue at the moment, so fix on of the grossly misnamed directories. We usually never use "virtual" as a shortcut for virtualization in the kernel, but always virt, as seen in the virt/ top-level directory. Fix up the documentation to match that. Fixes: ed16648eb5b8 ("Move kvm, uml, and lguest subdirectories under a common "virtual" directory, I.E:") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-05kvm: Convert kvm_lock to a mutexJunaid Shahid1-3/+1
It doesn't seem as if there is any particular need for kvm_lock to be a spinlock, so convert the lock to a mutex so that sleepable functions (in particular cond_resched()) can be called while holding it. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-09kvm: x86: mmu: Update documentation for fast page fault mechanismJunaid Shahid1-4/+27
Add a brief description of the lockless access tracking mechanism to the documentation of fast page faults in locking.txt. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-12-16KVM: hyperv: fix locking of struct kvm_hv fieldsPaolo Bonzini1-2/+6
Introduce a new mutex to avoid an AB-BA deadlock between kvm->lock and vcpu->mutex. Protect accesses in kvm_hv_setup_tsc_page too, as suggested by Roman. Reported-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-27KVM: document lock ordersPaolo Bonzini1-1/+11
This is long overdue, and not really hard. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <1476357057-17899-1-git-send-email-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14KVM: x86: Fix typosAndrea Gelmini1-2/+2
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: Update Posted-Interrupts Descriptor when vCPU is blockedFeng Wu1-0/+12
This patch updates the Posted-Interrupts Descriptor when vCPU is blocked. pre-block: - Add the vCPU to the blocked per-CPU list - Set 'NV' to POSTED_INTR_WAKEUP_VECTOR post-block: - Remove the vCPU from the per-CPU list Signed-off-by: Feng Wu <feng.wu@intel.com> [Concentrate invocation of pre/post-block hooks to vcpu_block. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-12-31KVM: doc: Fix typo in doc/virtual/kvmMasanari Iida1-2/+2
Correct spelling typo in Documentations/virtual/kvm Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2013-09-30KVM: Convert kvm_lock back to non-raw spinlockPaolo Bonzini1-1/+1
In commit e935b8372cf8 ("KVM: Convert kvm_lock to raw_spinlock"), the kvm_lock was made a raw lock. However, the kvm mmu_shrink() function tries to grab the (non-raw) mmu_lock within the scope of the raw locked kvm_lock being held. This leads to the following: BUG: sleeping function called from invalid context at kernel/rtmutex.c:659 in_atomic(): 1, irqs_disabled(): 0, pid: 55, name: kswapd0 Preemption disabled at:[<ffffffffa0376eac>] mmu_shrink+0x5c/0x1b0 [kvm] Pid: 55, comm: kswapd0 Not tainted 3.4.34_preempt-rt Call Trace: [<ffffffff8106f2ad>] __might_sleep+0xfd/0x160 [<ffffffff817d8d64>] rt_spin_lock+0x24/0x50 [<ffffffffa0376f3c>] mmu_shrink+0xec/0x1b0 [kvm] [<ffffffff8111455d>] shrink_slab+0x17d/0x3a0 [<ffffffff81151f00>] ? mem_cgroup_iter+0x130/0x260 [<ffffffff8111824a>] balance_pgdat+0x54a/0x730 [<ffffffff8111fe47>] ? set_pgdat_percpu_threshold+0xa7/0xd0 [<ffffffff811185bf>] kswapd+0x18f/0x490 [<ffffffff81070961>] ? get_parent_ip+0x11/0x50 [<ffffffff81061970>] ? __init_waitqueue_head+0x50/0x50 [<ffffffff81118430>] ? balance_pgdat+0x730/0x730 [<ffffffff81060d2b>] kthread+0xdb/0xe0 [<ffffffff8106e122>] ? finish_task_switch+0x52/0x100 [<ffffffff817e1e94>] kernel_thread_helper+0x4/0x10 [<ffffffff81060c50>] ? __init_kthread_worker+0x After the previous patch, kvm_lock need not be a raw spinlock anymore, so change it back. Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: kvm@vger.kernel.org Cc: gleb@redhat.com Cc: jan.kiszka@siemens.com Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-30KVM: protect kvm_usage_count with its own spinlockPaolo Bonzini1-1/+5
The VM list need not be protected by a raw spinlock. Separate the two so that kvm_lock can be made non-raw. Cc: kvm@vger.kernel.org Cc: gleb@redhat.com Cc: jan.kiszka@siemens.com Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-24KVM: Add documentation for kvm->srcu lockThomas Huth1-0/+11
This patch documents the kvm->srcu lock (using the information from a mail which has been posted by Marcelo Tosatti to the kvm mailing list some months ago, see the following URL for details: http://www.mail-archive.com/kvm@vger.kernel.org/msg90040.html ) Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-07-11KVM: MMU: document mmu-lock and fast page faultXiao Guangrong1-1/+129
Document fast page fault and mmu-lock in locking.txt Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-06Move kvm, uml, and lguest subdirectories under a common "virtual" directory, ↵Rob Landley1-0/+25
I.E: cd Documentation mkdir virtual git mv kvm uml lguest virtual Signed-off-by: Rob Landley <rlandley@parallels.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>