Srivatsa S. Bhat
2022-Jun-13 18:48 UTC
[PATCH 29/36] cpuidle, xenpv: Make more PARAVIRT_XXL noinstr clean
On 6/8/22 4:27 PM, Peter Zijlstra wrote:> vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section > vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section > vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section > > Signed-off-by: Peter Zijlstra (Intel) <peterz at infradead.org>Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa at csail.mit.edu> Regards, Srivatsa VMware Photon OS> --- > arch/x86/include/asm/paravirt.h | 6 ++++-- > arch/x86/include/asm/special_insns.h | 4 ++-- > arch/x86/include/asm/xen/hypercall.h | 2 +- > arch/x86/kernel/paravirt.c | 14 ++++++++++++-- > arch/x86/xen/enlighten_pv.c | 2 +- > arch/x86/xen/irq.c | 2 +- > 6 files changed, 21 insertions(+), 9 deletions(-) > > --- a/arch/x86/include/asm/paravirt.h > +++ b/arch/x86/include/asm/paravirt.h > @@ -168,7 +168,7 @@ static inline void __write_cr4(unsigned > PVOP_VCALL1(cpu.write_cr4, x); > } > > -static inline void arch_safe_halt(void) > +static __always_inline void arch_safe_halt(void) > { > PVOP_VCALL0(irq.safe_halt); > } > @@ -178,7 +178,9 @@ static inline void halt(void) > PVOP_VCALL0(irq.halt); > } > > -static inline void wbinvd(void) > +extern noinstr void pv_native_wbinvd(void); > + > +static __always_inline void wbinvd(void) > { > PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV)); > } > --- a/arch/x86/include/asm/special_insns.h > +++ b/arch/x86/include/asm/special_insns.h > @@ -115,7 +115,7 @@ static inline void wrpkru(u32 pkru) > } > #endif > > -static inline void native_wbinvd(void) > +static __always_inline void native_wbinvd(void) > { > asm volatile("wbinvd": : :"memory"); > } > @@ -179,7 +179,7 @@ static inline void __write_cr4(unsigned > native_write_cr4(x); > } > > -static inline void wbinvd(void) > +static __always_inline void wbinvd(void) > { > native_wbinvd(); > } > --- a/arch/x86/include/asm/xen/hypercall.h > +++ b/arch/x86/include/asm/xen/hypercall.h > @@ -382,7 +382,7 @@ MULTI_stack_switch(struct multicall_entr > } > #endif > > -static inline int > +static __always_inline int > HYPERVISOR_sched_op(int cmd, void *arg) > { > return _hypercall2(int, sched_op, cmd, arg); > --- a/arch/x86/kernel/paravirt.c > +++ b/arch/x86/kernel/paravirt.c > @@ -233,6 +233,11 @@ static noinstr void pv_native_set_debugr > native_set_debugreg(regno, val); > } > > +noinstr void pv_native_wbinvd(void) > +{ > + native_wbinvd(); > +} > + > static noinstr void pv_native_irq_enable(void) > { > native_irq_enable(); > @@ -242,6 +247,11 @@ static noinstr void pv_native_irq_disabl > { > native_irq_disable(); > } > + > +static noinstr void pv_native_safe_halt(void) > +{ > + native_safe_halt(); > +} > #endif > > enum paravirt_lazy_mode paravirt_get_lazy_mode(void) > @@ -273,7 +283,7 @@ struct paravirt_patch_template pv_ops > .cpu.read_cr0 = native_read_cr0, > .cpu.write_cr0 = native_write_cr0, > .cpu.write_cr4 = native_write_cr4, > - .cpu.wbinvd = native_wbinvd, > + .cpu.wbinvd = pv_native_wbinvd, > .cpu.read_msr = native_read_msr, > .cpu.write_msr = native_write_msr, > .cpu.read_msr_safe = native_read_msr_safe, > @@ -307,7 +317,7 @@ struct paravirt_patch_template pv_ops > .irq.save_fl = __PV_IS_CALLEE_SAVE(native_save_fl), > .irq.irq_disable = __PV_IS_CALLEE_SAVE(pv_native_irq_disable), > .irq.irq_enable = __PV_IS_CALLEE_SAVE(pv_native_irq_enable), > - .irq.safe_halt = native_safe_halt, > + .irq.safe_halt = pv_native_safe_halt, > .irq.halt = native_halt, > #endif /* CONFIG_PARAVIRT_XXL */ > > --- a/arch/x86/xen/enlighten_pv.c > +++ b/arch/x86/xen/enlighten_pv.c > @@ -1019,7 +1019,7 @@ static const typeof(pv_ops) xen_cpu_ops > > .write_cr4 = xen_write_cr4, > > - .wbinvd = native_wbinvd, > + .wbinvd = pv_native_wbinvd, > > .read_msr = xen_read_msr, > .write_msr = xen_write_msr, > --- a/arch/x86/xen/irq.c > +++ b/arch/x86/xen/irq.c > @@ -24,7 +24,7 @@ noinstr void xen_force_evtchn_callback(v > (void)HYPERVISOR_xen_version(0, NULL); > } > > -static void xen_safe_halt(void) > +static noinstr void xen_safe_halt(void) > { > /* Blocking includes an implicit local_irq_enable(). */ > if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0) > >
Nadav Amit
2022-Jun-13 19:23 UTC
[Pv-drivers] [PATCH 29/36] cpuidle, xenpv: Make more PARAVIRT_XXL noinstr clean
On Jun 13, 2022, at 11:48 AM, Srivatsa S. Bhat <srivatsa at csail.mit.edu> wrote:> ? External Email > > On 6/8/22 4:27 PM, Peter Zijlstra wrote: >> vmlinux.o: warning: objtool: acpi_idle_enter_s2idle+0xde: call to wbinvd() leaves .noinstr.text section >> vmlinux.o: warning: objtool: default_idle+0x4: call to arch_safe_halt() leaves .noinstr.text section >> vmlinux.o: warning: objtool: xen_safe_halt+0xa: call to HYPERVISOR_sched_op.constprop.0() leaves .noinstr.text section >> >> Signed-off-by: Peter Zijlstra (Intel) <peterz at infradead.org> > > Reviewed-by: Srivatsa S. Bhat (VMware) <srivatsa at csail.mit.edu> > >> >> -static inline void wbinvd(void) >> +extern noinstr void pv_native_wbinvd(void); >> + >> +static __always_inline void wbinvd(void) >> { >> PVOP_ALT_VCALL0(cpu.wbinvd, "wbinvd", ALT_NOT(X86_FEATURE_XENPV)); >> }I guess it is yet another instance of wrong accounting of GCC for the assembly blocks? weight. I guess it is not a solution for older GCCs, but presumably ____PVOP_ALT_CALL() and friends should have used asm_inline or some new ?asm_volatile_inline? variant.