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
This commit is contained in:
Andy Lutomirski
2020-02-28 10:42:48 -08:00
committed by Thomas Gleixner
parent af1e56b785
commit ef68017eb5
8 changed files with 57 additions and 37 deletions

View File

@@ -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);
};