Paravirt emits indirect calls which get flagged by objtool retpoline
checks, annotate it away because all these indirect calls will be
patched out before we start userspace.
Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
arch/x86/include/asm/paravirt.h | 22 ++++++++++++++++++----
arch/x86/include/asm/paravirt_types.h | 7 ++++++-
2 files changed, 24 insertions(+), 5 deletions(-)
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -828,6 +828,12 @@ extern void default_banner(void);
.short clobbers; \
.popsection
+#define PARA_RETPOLINE_SAFE \
+ 773:; \
+ .pushsection .discard.retpoline_safe; \
+ _ASM_PTR 773b; \
+ .popsection
+
#define COND_PUSH(set, mask, reg) \
.if ((~(set)) & mask); push %reg; .endif
@@ -879,23 +885,27 @@ extern void default_banner(void);
#define INTERRUPT_RETURN \
PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_iret), CLBR_NONE, \
- jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_iret))
+ PARA_RETPOLINE_SAFE; \
+ jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_iret);)
#define DISABLE_INTERRUPTS(clobbers) \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_disable), clobbers, \
PV_SAVE_REGS(clobbers | CLBR_CALLEE_SAVE); \
+ PARA_RETPOLINE_SAFE; \
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_disable); \
PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
#define ENABLE_INTERRUPTS(clobbers) \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_enable), clobbers, \
PV_SAVE_REGS(clobbers | CLBR_CALLEE_SAVE); \
+ PARA_RETPOLINE_SAFE; \
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_enable); \
PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
#ifdef CONFIG_X86_32
#define GET_CR0_INTO_EAX \
push %ecx; push %edx; \
+ PARA_RETPOLINE_SAFE; \
call PARA_INDIRECT(pv_cpu_ops+PV_CPU_read_cr0); \
pop %edx; pop %ecx
#else /* !CONFIG_X86_32 */
@@ -917,21 +927,25 @@ extern void default_banner(void);
*/
#define SWAPGS \
PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_swapgs), CLBR_NONE, \
- call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs) \
+ PARA_RETPOLINE_SAFE; \
+ call PARA_INDIRECT(pv_cpu_ops+PV_CPU_swapgs); \
)
#define GET_CR2_INTO_RAX \
- call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2)
+ PARA_RETPOLINE_SAFE; \
+ call PARA_INDIRECT(pv_mmu_ops+PV_MMU_read_cr2);
#define USERGS_SYSRET64
\
PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_usergs_sysret64), \
CLBR_NONE, \
- jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_usergs_sysret64))
+ PARA_RETPOLINE_SAFE; \
+ jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_usergs_sysret64);)
#ifdef CONFIG_DEBUG_ENTRY
#define SAVE_FLAGS(clobbers) \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_save_fl), clobbers, \
PV_SAVE_REGS(clobbers | CLBR_CALLEE_SAVE); \
+ PARA_RETPOLINE_SAFE; \
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_save_fl); \
PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
#endif
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -392,7 +392,12 @@ int paravirt_disable_iospace(void);
* offset into the paravirt_patch_template structure, and can therefore be
* freely converted back into a structure offset.
*/
-#define PARAVIRT_CALL "call *%c[paravirt_opptr];"
+#define PARAVIRT_CALL \
+ "773:;\n" \
+ ".pushsection .discard.retpoline_safe\n" \
+ _ASM_PTR " 773b\n" \
+ ".popsection\n" \
+ "call *%c[paravirt_opptr];"
/*
* These macros are intended to wrap calls through one of the paravirt
