diff options
Diffstat (limited to 'arch/x86/entry/entry_64.S')
-rw-r--r-- | arch/x86/entry/entry_64.S | 26 |
1 files changed, 12 insertions, 14 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index bd52f675d11d..400908dff42e 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -46,14 +46,6 @@ .code64 .section .entry.text, "ax" -#ifdef CONFIG_PARAVIRT_XXL -SYM_CODE_START(native_usergs_sysret64) - UNWIND_HINT_EMPTY - swapgs - sysretq -SYM_CODE_END(native_usergs_sysret64) -#endif /* CONFIG_PARAVIRT_XXL */ - /* * 64-bit SYSCALL instruction entry. Up to 6 arguments in registers. * @@ -123,7 +115,12 @@ SYM_INNER_LABEL(entry_SYSCALL_64_after_hwframe, SYM_L_GLOBAL) * Try to use SYSRET instead of IRET if we're returning to * a completely clean 64-bit userspace context. If we're not, * go to the slow exit path. + * In the Xen PV case we must use iret anyway. */ + + ALTERNATIVE "", "jmp swapgs_restore_regs_and_return_to_usermode", \ + X86_FEATURE_XENPV + movq RCX(%rsp), %rcx movq RIP(%rsp), %r11 @@ -215,7 +212,8 @@ syscall_return_via_sysret: popq %rdi popq %rsp - USERGS_SYSRET64 + swapgs + sysretq SYM_CODE_END(entry_SYSCALL_64) /* @@ -669,7 +667,7 @@ native_irq_return_ldt: */ pushq %rdi /* Stash user RDI */ - SWAPGS /* to kernel GS */ + swapgs /* to kernel GS */ SWITCH_TO_KERNEL_CR3 scratch_reg=%rdi /* to kernel CR3 */ movq PER_CPU_VAR(espfix_waddr), %rdi @@ -699,7 +697,7 @@ native_irq_return_ldt: orq PER_CPU_VAR(espfix_stack), %rax SWITCH_TO_USER_CR3_STACK scratch_reg=%rdi - SWAPGS /* to user GS */ + swapgs /* to user GS */ popq %rdi /* Restore user RDI */ movq %rax, %rsp @@ -902,7 +900,7 @@ SYM_CODE_START_LOCAL(paranoid_entry) ret .Lparanoid_entry_swapgs: - SWAPGS + swapgs /* * The above SAVE_AND_SWITCH_TO_KERNEL_CR3 macro doesn't do an @@ -960,7 +958,7 @@ SYM_CODE_START_LOCAL(paranoid_exit) jnz restore_regs_and_return_to_kernel /* We are returning to a context with user GSBASE */ - SWAPGS_UNSAFE_STACK + swapgs jmp restore_regs_and_return_to_kernel SYM_CODE_END(paranoid_exit) @@ -1385,7 +1383,7 @@ nmi_no_fsgsbase: jnz nmi_restore nmi_swapgs: - SWAPGS_UNSAFE_STACK + swapgs nmi_restore: POP_REGS |