When working on a way to move out the posix cpu timer expiry out of the timer interrupt context, I noticed that KVM is not handling pending task work before entering a guest. A quick hack was to add that to the x86 KVM handling loop. The discussion ended with a request to make this a generic infrastructure possible with also moving the per arch implementations of the enter from and return to user space handling generic.
https://lore.kernel.org/r/89e42bcc-47a8-458b-b06a-d6a20d205...@amacapital.net The series implements the syscall enter/exit and the general exit to userspace work handling along with the pre guest enter functionality. Changes vs. RFC version: - Dropped ARM64 conversion as requested by ARM64 folks - Addressed various review comments (Peter, Andy, Mike, Paolo, Josh, Miroslav) - Picked up, fixed and completed Peter's patch which makes interrupt enable/disable symmetric in trap handlers - Completed the removal of irq disabling / irq tracing from low level ASM code - Moved KVM specific parts of the enter guest mode handling to KVM (Paolo) The series is also available from git: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git WIP/core.entry Thanks, tglx RFC version: https://lore.kernel.org/r/20190919150314.054351...@linutronix.de --- /Makefile | 3 arch/Kconfig | 3 arch/x86/Kconfig | 1 arch/x86/entry/calling.h | 12 + arch/x86/entry/common.c | 264 ++------------------------------ arch/x86/entry/entry_32.S | 41 ---- arch/x86/entry/entry_64.S | 32 --- arch/x86/entry/entry_64_compat.S | 30 --- arch/x86/include/asm/irqflags.h | 8 arch/x86/include/asm/paravirt.h | 9 - arch/x86/include/asm/signal.h | 1 arch/x86/include/asm/thread_info.h | 9 - arch/x86/kernel/signal.c | 2 arch/x86/kernel/traps.c | 33 ++-- arch/x86/kvm/x86.c | 17 -- arch/x86/mm/fault.c | 7 b/arch/x86/include/asm/entry-common.h | 104 ++++++++++++ b/arch/x86/kvm/Kconfig | 1 b/include/linux/entry-common.h | 280 ++++++++++++++++++++++++++++++++++ b/kernel/entry/common.c | 184 ++++++++++++++++++++++ include/linux/kvm_host.h | 64 +++++++ kernel/Makefile | 1 virt/kvm/Kconfig | 3 23 files changed, 735 insertions(+), 374 deletions(-)
