From 83b584d9c6a1494170abd3a8b24f41939b23d625 Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Mon, 15 Jul 2019 16:16:41 +0100 Subject: [PATCH] x86/paravirt: Drop {read,write}_cr8() hooks There is a lot of infrastructure for functionality which is used exclusively in __{save,restore}_processor_state() on the suspend/resume path. cr8 is an alias of APIC_TASKPRI, and APIC_TASKPRI is saved/restored by lapic_{suspend,resume}(). Saving and restoring cr8 independently of the rest of the Local APIC state isn't a clever thing to be doing. Delete the suspend/resume cr8 handling, which shrinks the size of struct saved_context, and allows for the removal of both PVOPS. Signed-off-by: Andrew Cooper Signed-off-by: Thomas Gleixner Reviewed-by: Juergen Gross Link: https://lkml.kernel.org/r/20190715151641.29210-1-andrew.cooper3@citrix.com --- arch/x86/include/asm/paravirt.h | 12 ------------ arch/x86/include/asm/paravirt_types.h | 5 ----- arch/x86/include/asm/special_insns.h | 24 ------------------------ arch/x86/include/asm/suspend_64.h | 2 +- arch/x86/kernel/asm-offsets_64.c | 1 - arch/x86/kernel/paravirt.c | 4 ---- arch/x86/power/cpu.c | 4 ---- arch/x86/xen/enlighten_pv.c | 15 --------------- 8 files changed, 1 insertion(+), 66 deletions(-) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index dce26f1d13e1..69089d46f128 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -139,18 +139,6 @@ static inline void __write_cr4(unsigned long x) PVOP_VCALL1(cpu.write_cr4, x); } -#ifdef CONFIG_X86_64 -static inline unsigned long read_cr8(void) -{ - return PVOP_CALL0(unsigned long, cpu.read_cr8); -} - -static inline void write_cr8(unsigned long x) -{ - PVOP_VCALL1(cpu.write_cr8, x); -} -#endif - static inline void arch_safe_halt(void) { PVOP_VCALL0(irq.safe_halt); diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 639b2df445ee..70b654f3ffe5 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -119,11 +119,6 @@ struct pv_cpu_ops { void (*write_cr4)(unsigned long); -#ifdef CONFIG_X86_64 - unsigned long (*read_cr8)(void); - void (*write_cr8)(unsigned long); -#endif - /* Segment descriptor handling */ void (*load_tr_desc)(void); void (*load_gdt)(const struct desc_ptr *); diff --git a/arch/x86/include/asm/special_insns.h b/arch/x86/include/asm/special_insns.h index 219be88a59d2..6d37b8fcfc77 100644 --- a/arch/x86/include/asm/special_insns.h +++ b/arch/x86/include/asm/special_insns.h @@ -73,20 +73,6 @@ static inline unsigned long native_read_cr4(void) void native_write_cr4(unsigned long val); -#ifdef CONFIG_X86_64 -static inline unsigned long native_read_cr8(void) -{ - unsigned long cr8; - asm volatile("movq %%cr8,%0" : "=r" (cr8)); - return cr8; -} - -static inline void native_write_cr8(unsigned long val) -{ - asm volatile("movq %0,%%cr8" :: "r" (val) : "memory"); -} -#endif - #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS static inline u32 rdpkru(void) { @@ -200,16 +186,6 @@ static inline void wbinvd(void) #ifdef CONFIG_X86_64 -static inline unsigned long read_cr8(void) -{ - return native_read_cr8(); -} - -static inline void write_cr8(unsigned long x) -{ - native_write_cr8(x); -} - static inline void load_gs_index(unsigned selector) { native_load_gs_index(selector); diff --git a/arch/x86/include/asm/suspend_64.h b/arch/x86/include/asm/suspend_64.h index a7af9f53c0cb..35bb35d28733 100644 --- a/arch/x86/include/asm/suspend_64.h +++ b/arch/x86/include/asm/suspend_64.h @@ -34,7 +34,7 @@ struct saved_context { */ unsigned long kernelmode_gs_base, usermode_gs_base, fs_base; - unsigned long cr0, cr2, cr3, cr4, cr8; + unsigned long cr0, cr2, cr3, cr4; u64 misc_enable; bool misc_enable_saved; struct saved_msrs saved_msrs; diff --git a/arch/x86/kernel/asm-offsets_64.c b/arch/x86/kernel/asm-offsets_64.c index d3d075226c0a..8b54d8e3a561 100644 --- a/arch/x86/kernel/asm-offsets_64.c +++ b/arch/x86/kernel/asm-offsets_64.c @@ -62,7 +62,6 @@ int main(void) ENTRY(cr2); ENTRY(cr3); ENTRY(cr4); - ENTRY(cr8); ENTRY(gdt_desc); BLANK(); #undef ENTRY diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 0aa6256eedd8..59d3d2763a9e 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -311,10 +311,6 @@ struct paravirt_patch_template pv_ops = { .cpu.read_cr0 = native_read_cr0, .cpu.write_cr0 = native_write_cr0, .cpu.write_cr4 = native_write_cr4, -#ifdef CONFIG_X86_64 - .cpu.read_cr8 = native_read_cr8, - .cpu.write_cr8 = native_write_cr8, -#endif .cpu.wbinvd = native_wbinvd, .cpu.read_msr = native_read_msr, .cpu.write_msr = native_write_msr, diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c index 24b079e94bc2..1c58d8982728 100644 --- a/arch/x86/power/cpu.c +++ b/arch/x86/power/cpu.c @@ -122,9 +122,6 @@ static void __save_processor_state(struct saved_context *ctxt) ctxt->cr2 = read_cr2(); ctxt->cr3 = __read_cr3(); ctxt->cr4 = __read_cr4(); -#ifdef CONFIG_X86_64 - ctxt->cr8 = read_cr8(); -#endif ctxt->misc_enable_saved = !rdmsrl_safe(MSR_IA32_MISC_ENABLE, &ctxt->misc_enable); msr_save_context(ctxt); @@ -207,7 +204,6 @@ static void notrace __restore_processor_state(struct saved_context *ctxt) #else /* CONFIG X86_64 */ wrmsrl(MSR_EFER, ctxt->efer); - write_cr8(ctxt->cr8); __write_cr4(ctxt->cr4); #endif write_cr3(ctxt->cr3); diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 7ceb32821093..58f79ab32358 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -877,16 +877,6 @@ static void xen_write_cr4(unsigned long cr4) native_write_cr4(cr4); } -#ifdef CONFIG_X86_64 -static inline unsigned long xen_read_cr8(void) -{ - return 0; -} -static inline void xen_write_cr8(unsigned long val) -{ - BUG_ON(val); -} -#endif static u64 xen_read_msr_safe(unsigned int msr, int *err) { @@ -1023,11 +1013,6 @@ static const struct pv_cpu_ops xen_cpu_ops __initconst = { .write_cr4 = xen_write_cr4, -#ifdef CONFIG_X86_64 - .read_cr8 = xen_read_cr8, - .write_cr8 = xen_write_cr8, -#endif - .wbinvd = native_wbinvd, .read_msr = xen_read_msr, -- 2.45.2