diff options
| author | Andy Lutomirski <luto@kernel.org> | 2020-02-28 10:42:48 -0800 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-05-19 15:53:57 +0200 |
| commit | ef68017eb5704eb2b0577c3aa6619e13caf2b59f (patch) | |
| tree | a2a446d82225fc8adf7badb026cb869573371a39 /arch/x86/include/asm | |
| parent | af1e56b78534c38bb0e0c712ca70e59f816b74e9 (diff) | |
| download | linux-ef68017eb5704eb2b0577c3aa6619e13caf2b59f.tar.gz | |
x86/kvm: Handle async page faults directly through do_page_fault()
KVM overloads #PF to indicate two types of not-actually-page-fault
events. Right now, the KVM guest code intercepts them by modifying
the IDT and hooking the #PF vector. This makes the already fragile
fault code even harder to understand, and it also pollutes call
traces with async_page_fault and do_async_page_fault for normal page
faults.
Clean it up by moving the logic into do_page_fault() using a static
branch. This gets rid of the platform trap_init override mechanism
completely.
[ tglx: Fixed up 32bit, removed error code from the async functions and
massaged coding style ]
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134059.169270470@linutronix.de
Diffstat (limited to 'arch/x86/include/asm')
| -rw-r--r-- | arch/x86/include/asm/kvm_para.h | 19 | ||||
| -rw-r--r-- | arch/x86/include/asm/x86_init.h | 2 |
2 files changed, 17 insertions, 4 deletions
diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index 9b4df6eaa11a..5261363adda3 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -91,8 +91,18 @@ unsigned int kvm_arch_para_hints(void); void kvm_async_pf_task_wait(u32 token, int interrupt_kernel); void kvm_async_pf_task_wake(u32 token); u32 kvm_read_and_reset_pf_reason(void); -extern void kvm_disable_steal_time(void); -void do_async_page_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address); +void kvm_disable_steal_time(void); +bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token); + +DECLARE_STATIC_KEY_FALSE(kvm_async_pf_enabled); + +static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token) +{ + if (static_branch_unlikely(&kvm_async_pf_enabled)) + return __kvm_handle_async_pf(regs, token); + else + return false; +} #ifdef CONFIG_PARAVIRT_SPINLOCKS void __init kvm_spinlock_init(void); @@ -130,6 +140,11 @@ static inline void kvm_disable_steal_time(void) { return; } + +static inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token) +{ + return false; +} #endif #endif /* _ASM_X86_KVM_PARA_H */ diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index 96d9cd208610..6807153c0410 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -50,14 +50,12 @@ struct x86_init_resources { * @pre_vector_init: init code to run before interrupt vectors * are set up. * @intr_init: interrupt init code - * @trap_init: platform specific trap setup * @intr_mode_select: interrupt delivery mode selection * @intr_mode_init: interrupt delivery mode setup */ struct x86_init_irqs { void (*pre_vector_init)(void); void (*intr_init)(void); - void (*trap_init)(void); void (*intr_mode_select)(void); void (*intr_mode_init)(void); }; |