diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2021-06-24 11:41:13 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2021-09-17 13:11:50 +0200 |
| commit | 0a53c9acf4da51a75392b0b543ce5eaae78a567f (patch) | |
| tree | 7e9465b34506f3eca06c3b235bd920e2802a9c9d | |
| parent | eac46b323b28215ad19d53390737df4aa336ac14 (diff) | |
x86/xen: Make read_cr2() noinstr
vmlinux.o: warning: objtool: pv_ops[41]: native_read_cr2
vmlinux.o: warning: objtool: pv_ops[41]: xen_read_cr2
vmlinux.o: warning: objtool: pv_ops[41]: xen_read_cr2_direct
vmlinux.o: warning: objtool: exc_double_fault()+0x15: call to pv_ops[41]() leaves .noinstr.text section
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20210624095148.500331616@infradead.org
| -rw-r--r-- | arch/x86/include/asm/paravirt.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/paravirt.c | 7 | ||||
| -rw-r--r-- | arch/x86/xen/xen-asm.S | 2 |
3 files changed, 9 insertions, 2 deletions
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index a13a9a346539..8878065107a2 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -133,7 +133,7 @@ static inline void write_cr0(unsigned long x) PVOP_VCALL1(cpu.write_cr0, x); } -static inline unsigned long read_cr2(void) +static __always_inline unsigned long read_cr2(void) { return PVOP_ALT_CALLEE0(unsigned long, mmu.read_cr2, "mov %%cr2, %%rax;", diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 04cafc057bed..e351014fd62e 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -218,6 +218,11 @@ void paravirt_end_context_switch(struct task_struct *next) if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES)) arch_enter_lazy_mmu_mode(); } + +static noinstr unsigned long pv_native_read_cr2(void) +{ + return native_read_cr2(); +} #endif enum paravirt_lazy_mode paravirt_get_lazy_mode(void) @@ -298,7 +303,7 @@ struct paravirt_patch_template pv_ops = { .mmu.exit_mmap = paravirt_nop, #ifdef CONFIG_PARAVIRT_XXL - .mmu.read_cr2 = __PV_IS_CALLEE_SAVE(native_read_cr2), + .mmu.read_cr2 = __PV_IS_CALLEE_SAVE(pv_native_read_cr2), .mmu.write_cr2 = native_write_cr2, .mmu.read_cr3 = __native_read_cr3, .mmu.write_cr3 = native_write_cr3, diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S index 1e626444712b..aef4a1e8f33f 100644 --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -102,6 +102,7 @@ SYM_FUNC_START(check_events) ret SYM_FUNC_END(check_events) +.pushsection .noinstr.text, "ax" SYM_FUNC_START(xen_read_cr2) FRAME_BEGIN _ASM_MOV PER_CPU_VAR(xen_vcpu), %_ASM_AX @@ -116,6 +117,7 @@ SYM_FUNC_START(xen_read_cr2_direct) FRAME_END ret SYM_FUNC_END(xen_read_cr2_direct); +.popsection .macro xen_pv_trap name SYM_CODE_START(xen_\name) |