Commit 83b584d9 authored by Andrew Cooper's avatar Andrew Cooper Committed by Thomas Gleixner
Browse files

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: default avatarAndrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20190715151641.29210-1-andrew.cooper3@citrix.com
parent 229b969b

arch/x86/include/asm/paravirt.h

+0 −12
Original line number Diff line number Diff line
@@ -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);

arch/x86/include/asm/paravirt_types.h

+0 −5
Original line number Diff line number Diff line
@@ -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 *);

arch/x86/include/asm/special_insns.h

+0 −24
Original line number Diff line number Diff line
@@ -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);

arch/x86/include/asm/suspend_64.h

+1 −1
Original line number Diff line number Diff line
@@ -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;

arch/x86/kernel/asm-offsets_64.c

+0 −1
Original line number Diff line number Diff line
@@ -62,7 +62,6 @@ int main(void) 
	ENTRY(cr2);

	ENTRY(cr3);

	ENTRY(cr4);

	ENTRY(cr8);

	ENTRY(gdt_desc);

	BLANK();

#undef ENTRY

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