diff options
| author | Peter Xu <peterx@redhat.com> | 2019-05-08 11:15:47 +0200 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-05-08 13:48:24 +0200 |
| commit | d7547c55cbe7471255ca51f14bcd4699f5eaabe5 (patch) | |
| tree | 1d616aada1dec45414a38ed39f4017223ddccea8 /Documentation | |
| parent | KVM: Fix kvm_clear_dirty_log_protect off-by-(minus-)one (diff) | |
| download | linux-d7547c55cbe7471255ca51f14bcd4699f5eaabe5.tar.xz linux-d7547c55cbe7471255ca51f14bcd4699f5eaabe5.zip | |
KVM: Introduce KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
The previous KVM_CAP_MANUAL_DIRTY_LOG_PROTECT has some problem which
blocks the correct usage from userspace. Obsolete the old one and
introduce a new capability bit for it.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 675cb0bea903..47a5eb00bc53 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -330,7 +330,7 @@ They must be less than the value that KVM_CHECK_EXTENSION returns for the KVM_CAP_MULTI_ADDRESS_SPACE capability. The bits in the dirty bitmap are cleared before the ioctl returns, unless -KVM_CAP_MANUAL_DIRTY_LOG_PROTECT is enabled. For more information, +KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is enabled. For more information, see the description of the capability. 4.9 KVM_SET_MEMORY_ALIAS @@ -3791,7 +3791,7 @@ to I/O ports. 4.117 KVM_CLEAR_DIRTY_LOG (vm ioctl) -Capability: KVM_CAP_MANUAL_DIRTY_LOG_PROTECT +Capability: KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 Architectures: x86 Type: vm ioctl Parameters: struct kvm_dirty_log (in) @@ -3824,10 +3824,10 @@ the address space for which you want to return the dirty bitmap. They must be less than the value that KVM_CHECK_EXTENSION returns for the KVM_CAP_MULTI_ADDRESS_SPACE capability. -This ioctl is mostly useful when KVM_CAP_MANUAL_DIRTY_LOG_PROTECT +This ioctl is mostly useful when KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is enabled; for more information, see the description of the capability. However, it can always be used as long as KVM_CHECK_EXTENSION confirms -that KVM_CAP_MANUAL_DIRTY_LOG_PROTECT is present. +that KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is present. 4.118 KVM_GET_SUPPORTED_HV_CPUID @@ -4780,7 +4780,7 @@ and injected exceptions. * For the new DR6 bits, note that bit 16 is set iff the #DB exception will clear DR6.RTM. -7.18 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT +7.18 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 Architectures: all Parameters: args[0] whether feature should be enabled or not @@ -4803,6 +4803,11 @@ while userspace can see false reports of dirty pages. Manual reprotection helps reducing this time, improving guest performance and reducing the number of dirty log false positives. +KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 was previously available under the name +KVM_CAP_MANUAL_DIRTY_LOG_PROTECT, but the implementation had bugs that make +it hard or impossible to use it correctly. The availability of +KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 signals that those bugs are fixed. +Userspace should not try to use KVM_CAP_MANUAL_DIRTY_LOG_PROTECT. 8. Other capabilities. ---------------------- |