x86, xsave: keep the XSAVE feature mask as an u64 (6152e4b1) · Commits · e / devices / android_kernel_oneplus_sm8150

arch/x86/kernel/i387.c

+5 −7

Original line number	Original line	Diff line number	Diff line
	@@ -552,18 +552,17 @@ static int restore_i387_xsave(void __user *buf)
	(struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0];		(struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0];
	struct xsave_hdr_struct *xsave_hdr =		struct xsave_hdr_struct *xsave_hdr =
	&current->thread.xstate->xsave.xsave_hdr;		&current->thread.xstate->xsave.xsave_hdr;
	unsigned int lmask, hmask;		u64 mask;
	int err;		int err;

	if (check_for_xstate(fx, buf, &fx_sw_user))		if (check_for_xstate(fx, buf, &fx_sw_user))
	goto fx_only;		goto fx_only;

	lmask = fx_sw_user.xstate_bv;		mask = fx_sw_user.xstate_bv;
	hmask = fx_sw_user.xstate_bv >> 32;

	err = restore_i387_fxsave(buf, fx_sw_user.xstate_size);		err = restore_i387_fxsave(buf, fx_sw_user.xstate_size);

	xsave_hdr->xstate_bv &= (pcntxt_lmask \| (((u64) pcntxt_hmask) << 32));		xsave_hdr->xstate_bv &= pcntxt_mask;
	/*		/*
	* These bits must be zero.		* These bits must be zero.
	*/		*/
	@@ -573,9 +572,8 @@ static int restore_i387_xsave(void __user *buf)
	* Init the state that is not present in the memory layout		* Init the state that is not present in the memory layout
	* and enabled by the OS.		* and enabled by the OS.
	*/		*/
	lmask = ~(pcntxt_lmask & ~lmask);		mask = ~(pcntxt_mask & ~mask);
	hmask = ~(pcntxt_hmask & ~hmask);		xsave_hdr->xstate_bv &= mask;
	xsave_hdr->xstate_bv &= (lmask \| (((u64) hmask) << 32));

	return err;		return err;
	fx_only:		fx_only:

arch/x86/kernel/xsave.c

+17 −28

Original line number	Original line	Diff line number	Diff line
	@@ -9,11 +9,12 @@
	#ifdef CONFIG_IA32_EMULATION		#ifdef CONFIG_IA32_EMULATION
	#include <asm/sigcontext32.h>		#include <asm/sigcontext32.h>
	#endif		#endif
			#include <asm/xcr.h>

	/*		/*
	* Supported feature mask by the CPU and the kernel.		* Supported feature mask by the CPU and the kernel.
	*/		*/
	unsigned int pcntxt_hmask, pcntxt_lmask;		u64 pcntxt_mask;

	struct _fpx_sw_bytes fx_sw_reserved;		struct _fpx_sw_bytes fx_sw_reserved;
	#ifdef CONFIG_IA32_EMULATION		#ifdef CONFIG_IA32_EMULATION
	@@ -127,30 +128,28 @@ int save_i387_xstate(void __user *buf)
	int restore_user_xstate(void __user *buf)		int restore_user_xstate(void __user *buf)
	{		{
	struct _fpx_sw_bytes fx_sw_user;		struct _fpx_sw_bytes fx_sw_user;
	unsigned int lmask, hmask;		u64 mask;
	int err;		int err;

	if (((unsigned long)buf % 64) \|\|		if (((unsigned long)buf % 64) \|\|
	check_for_xstate(buf, buf, &fx_sw_user))		check_for_xstate(buf, buf, &fx_sw_user))
	goto fx_only;		goto fx_only;

	lmask = fx_sw_user.xstate_bv;		mask = fx_sw_user.xstate_bv;
	hmask = fx_sw_user.xstate_bv >> 32;

	/*		/*
	* restore the state passed by the user.		* restore the state passed by the user.
	*/		*/
	err = xrestore_user(buf, lmask, hmask);		err = xrestore_user(buf, mask);
	if (err)		if (err)
	return err;		return err;

	/*		/*
	* init the state skipped by the user.		* init the state skipped by the user.
	*/		*/
	lmask = pcntxt_lmask & ~lmask;		mask = pcntxt_mask & ~mask;
	hmask = pcntxt_hmask & ~hmask;

	xrstor_state(init_xstate_buf, lmask, hmask);		xrstor_state(init_xstate_buf, mask);

	return 0;		return 0;

	@@ -160,8 +159,7 @@ int restore_user_xstate(void __user *buf)
	* memory layout. Restore just the FP/SSE and init all		* memory layout. Restore just the FP/SSE and init all
	* the other extended state.		* the other extended state.
	*/		*/
	xrstor_state(init_xstate_buf, pcntxt_lmask & ~XSTATE_FPSSE,		xrstor_state(init_xstate_buf, pcntxt_mask & ~XSTATE_FPSSE);
	pcntxt_hmask);
	return fxrstor_checking((__force struct i387_fxsave_struct *)buf);		return fxrstor_checking((__force struct i387_fxsave_struct *)buf);
	}		}

	@@ -231,8 +229,7 @@ void prepare_fx_sw_frame(void)

	fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;		fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;
	fx_sw_reserved.extended_size = sig_xstate_size;		fx_sw_reserved.extended_size = sig_xstate_size;
	fx_sw_reserved.xstate_bv = pcntxt_lmask \|		fx_sw_reserved.xstate_bv = pcntxt_mask;
	(((u64) (pcntxt_hmask)) << 32);
	fx_sw_reserved.xstate_size = xstate_size;		fx_sw_reserved.xstate_size = xstate_size;
	#ifdef CONFIG_IA32_EMULATION		#ifdef CONFIG_IA32_EMULATION
	memcpy(&fx_sw_reserved_ia32, &fx_sw_reserved,		memcpy(&fx_sw_reserved_ia32, &fx_sw_reserved,
	@@ -263,11 +260,8 @@ void __cpuinit xsave_init(void)
	/*		/*
	* Enable all the features that the HW is capable of		* Enable all the features that the HW is capable of
	* and the Linux kernel is aware of.		* and the Linux kernel is aware of.
	*
	* xsetbv();
	*/		*/
	asm volatile(".byte 0x0f,0x01,0xd1" : : "c" (0),		xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
	"a" (pcntxt_lmask), "d" (pcntxt_hmask));
	}		}

	/*		/*
	@@ -287,36 +281,31 @@ void __init xsave_cntxt_init(void)
	unsigned int eax, ebx, ecx, edx;		unsigned int eax, ebx, ecx, edx;

	cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);		cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);
			pcntxt_mask = eax + ((u64)edx << 32);

	pcntxt_lmask = eax;		if ((pcntxt_mask & XSTATE_FPSSE) != XSTATE_FPSSE) {
	pcntxt_hmask = edx;		printk(KERN_ERR "FP/SSE not shown under xsave features 0x%llx\n",
			pcntxt_mask);
	if ((pcntxt_lmask & XSTATE_FPSSE) != XSTATE_FPSSE) {
	printk(KERN_ERR "FP/SSE not shown under xsave features %x\n",
	pcntxt_lmask);
	BUG();		BUG();
	}		}

	/*		/*
	* for now OS knows only about FP/SSE		* for now OS knows only about FP/SSE
	*/		*/
	pcntxt_lmask = pcntxt_lmask & XCNTXT_LMASK;		pcntxt_mask = pcntxt_mask & XCNTXT_MASK;
	pcntxt_hmask = pcntxt_hmask & XCNTXT_HMASK;

	xsave_init();		xsave_init();

	/*		/*
	* Recompute the context size for enabled features		* Recompute the context size for enabled features
	*/		*/
	cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);		cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);

	xstate_size = ebx;		xstate_size = ebx;

	prepare_fx_sw_frame();		prepare_fx_sw_frame();

	setup_xstate_init();		setup_xstate_init();

	printk(KERN_INFO "xsave/xrstor: enabled xstate_bv 0x%Lx, "		printk(KERN_INFO "xsave/xrstor: enabled xstate_bv 0x%llx, "
	"cntxt size 0x%x\n",		"cntxt size 0x%x\n",
	(pcntxt_lmask \| ((u64) pcntxt_hmask << 32)), xstate_size);		pcntxt_mask, xstate_size);
	}		}

include/asm-x86/xsave.h

+11 −7

Original line number	Original line	Diff line number	Diff line
	#ifndef __ASM_X86_XSAVE_H		#ifndef __ASM_X86_XSAVE_H
	#define __ASM_X86_XSAVE_H		#define __ASM_X86_XSAVE_H

			#include <linux/types.h>
	#include <asm/processor.h>		#include <asm/processor.h>
	#include <asm/i387.h>		#include <asm/i387.h>

	@@ -14,8 +15,7 @@
	/*		/*
	* These are the features that the OS can handle currently.		* These are the features that the OS can handle currently.
	*/		*/
	#define XCNTXT_LMASK (XSTATE_FP \| XSTATE_SSE)		#define XCNTXT_MASK (XSTATE_FP \| XSTATE_SSE)
	#define XCNTXT_HMASK 0x0

	#ifdef CONFIG_X86_64		#ifdef CONFIG_X86_64
	#define REX_PREFIX "0x48, "		#define REX_PREFIX "0x48, "
	@@ -23,7 +23,8 @@
	#define REX_PREFIX		#define REX_PREFIX
	#endif		#endif

	extern unsigned int xstate_size, pcntxt_hmask, pcntxt_lmask;		extern unsigned int xstate_size;
			extern u64 pcntxt_mask;
	extern struct xsave_struct *init_xstate_buf;		extern struct xsave_struct *init_xstate_buf;

	extern void xsave_cntxt_init(void);		extern void xsave_cntxt_init(void);
	@@ -73,12 +74,12 @@ static inline int xsave_user(struct xsave_struct __user *buf)
	return err;		return err;
	}		}

	static inline int xrestore_user(struct xsave_struct __user *buf,		static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
	unsigned int lmask,
	unsigned int hmask)
	{		{
	int err;		int err;
	struct xsave_struct xstate = ((__force struct xsave_struct )buf);		struct xsave_struct xstate = ((__force struct xsave_struct )buf);
			u32 lmask = mask;
			u32 hmask = mask >> 32;

	__asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"		__asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
	"2:\n"		"2:\n"
	@@ -96,8 +97,11 @@ static inline int xrestore_user(struct xsave_struct __user *buf,
	return err;		return err;
	}		}

	static inline void xrstor_state(struct xsave_struct *fx, int lmask, int hmask)		static inline void xrstor_state(struct xsave_struct *fx, u64 mask)
	{		{
			u32 lmask = mask;
			u32 hmask = mask >> 32;

	asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"		asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
	: : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)		: : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
	: "memory");		: "memory");