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Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Peter Zijlstra , Andy Lutomirski , "Paul E. McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-hyperv@vger.kernel.org, rcu@vger.kernel.org, Nuno Das Neves , Mukesh R Content-Type: text/plain; charset="UTF-8" Move KVM's morphing of pending signals into userspace exits into KVM proper, and drop the @vcpu param from xfer_to_guest_mode_handle_work(). How KVM responds to -EINTR is a detail that really belongs in KVM itself, and invoking kvm_handle_signal_exit() from kernel code creates an inverted module dependency. E.g. attempting to move kvm_handle_signal_exit() into kvm_main.c would generate an linker error when building kvm.ko as a module. Dropping KVM details will also converting the KVM "entry" code into a more generic virtualization framework so that it can be used when running as a Hyper-V root partition. Lastly, eliminating usage of "struct kvm_vcpu" outside of KVM is also nice to have for KVM x86 developers, as keeping the details of kvm_vcpu purely within KVM allows changing the layout of the structure without having to boot into a new kernel, e.g. allows rebuilding and reloading kvm.ko with a modified kvm_vcpu structure as part of debug/development. Signed-off-by: Sean Christopherson --- arch/arm64/kvm/arm.c | 3 +-- arch/loongarch/kvm/vcpu.c | 3 +-- arch/riscv/kvm/vcpu.c | 3 +-- arch/x86/kvm/vmx/vmx.c | 1 - arch/x86/kvm/x86.c | 3 +-- include/linux/entry-kvm.h | 11 +++-------- include/linux/kvm_host.h | 13 ++++++++++++- kernel/entry/kvm.c | 13 +++++-------- 8 files changed, 24 insertions(+), 26 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 888f7c7abf54..418fd3043467 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -6,7 +6,6 @@ #include #include -#include #include #include #include @@ -1177,7 +1176,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) /* * Check conditions before entering the guest */ - ret = xfer_to_guest_mode_handle_work(vcpu); + ret = kvm_xfer_to_guest_mode_handle_work(vcpu); if (!ret) ret = 1; diff --git a/arch/loongarch/kvm/vcpu.c b/arch/loongarch/kvm/vcpu.c index d1b8c50941ca..514256b25ba1 100644 --- a/arch/loongarch/kvm/vcpu.c +++ b/arch/loongarch/kvm/vcpu.c @@ -4,7 +4,6 @@ */ #include -#include #include #include #include @@ -251,7 +250,7 @@ static int kvm_enter_guest_check(struct kvm_vcpu *vcpu) /* * Check conditions before entering the guest */ - ret = xfer_to_guest_mode_handle_work(vcpu); + ret = kvm_xfer_to_guest_mode_handle_work(vcpu); if (ret < 0) return ret; diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c index f001e56403f9..251e787f2ebc 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -7,7 +7,6 @@ */ #include -#include #include #include #include @@ -910,7 +909,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) run->exit_reason = KVM_EXIT_UNKNOWN; while (ret > 0) { /* Check conditions before entering the guest */ - ret = xfer_to_guest_mode_handle_work(vcpu); + ret = kvm_xfer_to_guest_mode_handle_work(vcpu); if (ret) continue; ret = 1; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index aa157fe5b7b3..d7c86613e50a 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -28,7 +28,6 @@ #include #include #include -#include #include #include diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a1c49bc681c4..0b13b8bf69e5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -59,7 +59,6 @@ #include #include #include -#include #include #include @@ -11241,7 +11240,7 @@ static int vcpu_run(struct kvm_vcpu *vcpu) if (__xfer_to_guest_mode_work_pending()) { kvm_vcpu_srcu_read_unlock(vcpu); - r = xfer_to_guest_mode_handle_work(vcpu); + r = kvm_xfer_to_guest_mode_handle_work(vcpu); kvm_vcpu_srcu_read_lock(vcpu); if (r) return r; diff --git a/include/linux/entry-kvm.h b/include/linux/entry-kvm.h index 16149f6625e4..3644de7e6019 100644 --- a/include/linux/entry-kvm.h +++ b/include/linux/entry-kvm.h @@ -21,8 +21,6 @@ _TIF_NOTIFY_SIGNAL | _TIF_NOTIFY_RESUME | \ ARCH_XFER_TO_GUEST_MODE_WORK) -struct kvm_vcpu; - /** * arch_xfer_to_guest_mode_handle_work - Architecture specific xfer to guest * mode work handling function. @@ -32,12 +30,10 @@ struct kvm_vcpu; * Invoked from xfer_to_guest_mode_handle_work(). Defaults to NOOP. Can be * replaced by architecture specific code. */ -static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu, - unsigned long ti_work); +static inline int arch_xfer_to_guest_mode_handle_work(unsigned long ti_work); #ifndef arch_xfer_to_guest_mode_work -static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu, - unsigned long ti_work) +static inline int arch_xfer_to_guest_mode_handle_work(unsigned long ti_work) { return 0; } @@ -46,11 +42,10 @@ static inline int arch_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu, /** * xfer_to_guest_mode_handle_work - Check and handle pending work which needs * to be handled before going to guest mode - * @vcpu: Pointer to current's VCPU data * * Returns: 0 or an error code */ -int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu); +int xfer_to_guest_mode_handle_work(void); /** * xfer_to_guest_mode_prepare - Perform last minute preparation work that diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 15656b7fba6c..598b9473e46d 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2,7 +2,7 @@ #ifndef __KVM_HOST_H #define __KVM_HOST_H - +#include #include #include #include @@ -2450,6 +2450,17 @@ static inline void kvm_handle_signal_exit(struct kvm_vcpu *vcpu) vcpu->run->exit_reason = KVM_EXIT_INTR; vcpu->stat.signal_exits++; } + +static inline int kvm_xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu) +{ + int r = xfer_to_guest_mode_handle_work(); + + if (r) { + WARN_ON_ONCE(r != -EINTR); + kvm_handle_signal_exit(vcpu); + } + return r; +} #endif /* CONFIG_KVM_XFER_TO_GUEST_WORK */ /* diff --git a/kernel/entry/kvm.c b/kernel/entry/kvm.c index 8485f63863af..6fc762eaacca 100644 --- a/kernel/entry/kvm.c +++ b/kernel/entry/kvm.c @@ -1,17 +1,14 @@ // SPDX-License-Identifier: GPL-2.0 #include -#include -static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work) +static int xfer_to_guest_mode_work(unsigned long ti_work) { do { int ret; - if (ti_work & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) { - kvm_handle_signal_exit(vcpu); + if (ti_work & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) return -EINTR; - } if (ti_work & (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)) schedule(); @@ -19,7 +16,7 @@ static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work) if (ti_work & _TIF_NOTIFY_RESUME) resume_user_mode_work(NULL); - ret = arch_xfer_to_guest_mode_handle_work(vcpu, ti_work); + ret = arch_xfer_to_guest_mode_handle_work(ti_work); if (ret) return ret; @@ -28,7 +25,7 @@ static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work) return 0; } -int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu) +int xfer_to_guest_mode_handle_work(void) { unsigned long ti_work; @@ -44,6 +41,6 @@ int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu) if (!(ti_work & XFER_TO_GUEST_MODE_WORK)) return 0; - return xfer_to_guest_mode_work(vcpu, ti_work); + return xfer_to_guest_mode_work(ti_work); } EXPORT_SYMBOL_GPL(xfer_to_guest_mode_handle_work); -- 2.51.0.268.g9569e192d0-goog