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/entry | |
| parent | af1e56b78534c38bb0e0c712ca70e59f816b74e9 (diff) | |
| download | linux-ef68017eb5704eb2b0577c3aa6619e13caf2b59f.tar.bz2 | |
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/entry')
| -rw-r--r-- | arch/x86/entry/entry_32.S | 8 | ||||
| -rw-r--r-- | arch/x86/entry/entry_64.S | 4 |
2 files changed, 0 insertions, 12 deletions
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index b67bae7091d7..8ba0985f5016 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -1693,14 +1693,6 @@ SYM_CODE_START(general_protection) jmp common_exception SYM_CODE_END(general_protection) -#ifdef CONFIG_KVM_GUEST -SYM_CODE_START(async_page_fault) - ASM_CLAC - pushl $do_async_page_fault - jmp common_exception_read_cr2 -SYM_CODE_END(async_page_fault) -#endif - SYM_CODE_START(rewind_stack_do_exit) /* Prevent any naive code from trying to unwind to our caller. */ xorl %ebp, %ebp diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 3063aa9090f9..9ab3ea6d02fc 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -1202,10 +1202,6 @@ idtentry xendebug do_debug has_error_code=0 idtentry general_protection do_general_protection has_error_code=1 idtentry page_fault do_page_fault has_error_code=1 read_cr2=1 -#ifdef CONFIG_KVM_GUEST -idtentry async_page_fault do_async_page_fault has_error_code=1 read_cr2=1 -#endif - #ifdef CONFIG_X86_MCE idtentry machine_check do_mce has_error_code=0 paranoid=1 #endif |