diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2020-05-21 22:05:26 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-06-11 15:15:08 +0200 |
| commit | 2f6474e4636bcc68af6c44abb2703f12d7f083da (patch) | |
| tree | 317a6b92fc169077e1eb9c3d7a10e3c62869109d /arch/x86/entry/entry_32.S | |
| parent | 1de16e0c17155d138282f3a9f65914a9a5da757e (diff) | |
x86/entry: Switch XEN/PV hypercall entry to IDTENTRY
Convert the XEN/PV hypercall to IDTENTRY:
- Emit the ASM stub with DECLARE_IDTENTRY
- Remove the ASM idtentry in 64-bit
- Remove the open coded ASM entry code in 32-bit
- Remove the old prototypes
The handler stubs need to stay in ASM code as they need corner case handling
and adjustment of the stack pointer.
Provide a new C function which invokes the entry/exit handling and calls
into the XEN handler on the interrupt stack if required.
The exit code is slightly different from the regular idtentry_exit() on
non-preemptible kernels. If the hypercall is preemptible and need_resched()
is set then XEN provides a preempt hypercall scheduling function.
Move this functionality into the entry code so it can use the existing
idtentry functionality.
[ mingo: Build fixes. ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com>
Tested-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20200521202118.055270078@linutronix.de
Diffstat (limited to 'arch/x86/entry/entry_32.S')
| -rw-r--r-- | arch/x86/entry/entry_32.S | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 28d13f07b84d..3ab04dca9aab 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -1298,7 +1298,13 @@ SYM_CODE_END(native_iret) #endif #ifdef CONFIG_XEN_PV -SYM_FUNC_START(xen_hypervisor_callback) +/* + * See comment in entry_64.S for further explanation + * + * Note: This is not an actual IDT entry point. It's a XEN specific entry + * point and therefore named to match the 64-bit trampoline counterpart. + */ +SYM_FUNC_START(xen_asm_exc_xen_hypervisor_callback) /* * Check to see if we got the event in the critical * region in xen_iret_direct, after we've reenabled @@ -1315,14 +1321,11 @@ SYM_FUNC_START(xen_hypervisor_callback) pushl $-1 /* orig_ax = -1 => not a system call */ SAVE_ALL ENCODE_FRAME_POINTER - TRACE_IRQS_OFF + mov %esp, %eax - call xen_evtchn_do_upcall -#ifndef CONFIG_PREEMPTION - call xen_maybe_preempt_hcall -#endif - jmp ret_from_intr -SYM_FUNC_END(xen_hypervisor_callback) + call xen_pv_evtchn_do_upcall + jmp handle_exception_return +SYM_FUNC_END(xen_asm_exc_xen_hypervisor_callback) /* * Hypervisor uses this for application faults while it executes. @@ -1464,6 +1467,7 @@ SYM_CODE_START_LOCAL_NOALIGN(handle_exception) movl %esp, %eax # pt_regs pointer CALL_NOSPEC edi +handle_exception_return: #ifdef CONFIG_VM86 movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS movb PT_CS(%esp), %al |