path: root/virt
diff options
authorThomas Gleixner <>2020-07-22 23:59:59 +0200
committerThomas Gleixner <>2020-07-24 15:03:42 +0200
commit935ace2fb5cc49ae88bd1f1735ddc51cdc2ebfb3 (patch)
treee39e6c089dd493abfe99507e089d45eb8d61da6f /virt
parenta5497bab5f72dce38a259a53fd3ac1239a7ecf40 (diff)
entry: Provide infrastructure for work before transitioning to guest mode
Entering a guest is similar to exiting to user space. Pending work like handling signals, rescheduling, task work etc. needs to be handled before that. Provide generic infrastructure to avoid duplication of the same handling code all over the place. The transfer to guest mode handling is different from the exit to usermode handling, e.g. vs. rseq and live patching, so a separate function is used. The initial list of work items handled is: TIF_SIGPENDING, TIF_NEED_RESCHED, TIF_NOTIFY_RESUME Architecture specific TIF flags can be added via defines in the architecture specific include files. The calling convention is also different from the syscall/interrupt entry functions as KVM invokes this from the outer vcpu_run() loop with interrupts and preemption enabled. To prevent missing a pending work item it invokes a check for pending TIF work from interrupt disabled code right before transitioning to guest mode. The lockdep, RCU and tracing state handling is also done directly around the switch to and from guest mode. Signed-off-by: Thomas Gleixner <> Link:
Diffstat (limited to 'virt')
1 files changed, 3 insertions, 0 deletions
diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index aad9284c043a..1c37ccd5d402 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -60,3 +60,6 @@ config HAVE_KVM_VCPU_RUN_PID_CHANGE
+ bool