summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/x86/ia32/ia32_signal.c51
-rw-r--r--arch/x86/kernel/Makefile2
-rw-r--r--arch/x86/kernel/cpu/common.c13
-rw-r--r--arch/x86/kernel/i387.c154
-rw-r--r--arch/x86/kernel/sigframe.h14
-rw-r--r--arch/x86/kernel/signal_32.c45
-rw-r--r--arch/x86/kernel/signal_64.c95
-rw-r--r--arch/x86/kernel/traps_32.c1
-rw-r--r--arch/x86/kernel/traps_64.c6
-rw-r--r--arch/x86/kernel/xsave.c316
-rw-r--r--arch/x86/power/cpu_32.c7
-rw-r--r--arch/x86/power/cpu_64.c7
-rw-r--r--include/asm-x86/i387.h84
-rw-r--r--include/asm-x86/processor-flags.h1
-rw-r--r--include/asm-x86/processor.h20
-rw-r--r--include/asm-x86/sigcontext.h87
-rw-r--r--include/asm-x86/sigcontext32.h6
-rw-r--r--include/asm-x86/thread_info.h1
-rw-r--r--include/asm-x86/ucontext.h6
-rw-r--r--include/asm-x86/xcr.h49
-rw-r--r--include/asm-x86/xsave.h118
21 files changed, 899 insertions, 184 deletions
diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index 20af4c79579..f25a1012400 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -179,9 +179,10 @@ struct sigframe
u32 pretcode;
int sig;
struct sigcontext_ia32 sc;
- struct _fpstate_ia32 fpstate;
+ struct _fpstate_ia32 fpstate_unused; /* look at kernel/sigframe.h */
unsigned int extramask[_COMPAT_NSIG_WORDS-1];
char retcode[8];
+ /* fp state follows here */
};
struct rt_sigframe
@@ -192,8 +193,8 @@ struct rt_sigframe
u32 puc;
compat_siginfo_t info;
struct ucontext_ia32 uc;
- struct _fpstate_ia32 fpstate;
char retcode[8];
+ /* fp state follows here */
};
#define COPY(x) { \
@@ -215,7 +216,7 @@ static int ia32_restore_sigcontext(struct pt_regs *regs,
unsigned int *peax)
{
unsigned int tmpflags, gs, oldgs, err = 0;
- struct _fpstate_ia32 __user *buf;
+ void __user *buf;
u32 tmp;
/* Always make any pending restarted system calls return -EINTR */
@@ -259,26 +260,12 @@ static int ia32_restore_sigcontext(struct pt_regs *regs,
err |= __get_user(tmp, &sc->fpstate);
buf = compat_ptr(tmp);
- if (buf) {
- if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
- goto badframe;
- err |= restore_i387_ia32(buf);
- } else {
- struct task_struct *me = current;
-
- if (used_math()) {
- clear_fpu(me);
- clear_used_math();
- }
- }
+ err |= restore_i387_xstate_ia32(buf);
err |= __get_user(tmp, &sc->ax);
*peax = tmp;
return err;
-
-badframe:
- return 1;
}
asmlinkage long sys32_sigreturn(struct pt_regs *regs)
@@ -350,7 +337,7 @@ badframe:
*/
static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
- struct _fpstate_ia32 __user *fpstate,
+ void __user *fpstate,
struct pt_regs *regs, unsigned int mask)
{
int tmp, err = 0;
@@ -381,7 +368,7 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
err |= __put_user((u32)regs->flags, &sc->flags);
err |= __put_user((u32)regs->sp, &sc->sp_at_signal);
- tmp = save_i387_ia32(fpstate);
+ tmp = save_i387_xstate_ia32(fpstate);
if (tmp < 0)
err = -EFAULT;
else {
@@ -402,7 +389,8 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
* Determine which stack to use..
*/
static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
- size_t frame_size)
+ size_t frame_size,
+ void **fpstate)
{
unsigned long sp;
@@ -421,6 +409,11 @@ static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
ka->sa.sa_restorer)
sp = (unsigned long) ka->sa.sa_restorer;
+ if (used_math()) {
+ sp = sp - sig_xstate_ia32_size;
+ *fpstate = (struct _fpstate_ia32 *) sp;
+ }
+
sp -= frame_size;
/* Align the stack pointer according to the i386 ABI,
* i.e. so that on function entry ((sp + 4) & 15) == 0. */
@@ -434,6 +427,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
struct sigframe __user *frame;
void __user *restorer;
int err = 0;
+ void __user *fpstate = NULL;
/* copy_to_user optimizes that into a single 8 byte store */
static const struct {
@@ -448,7 +442,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
0,
};
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -457,8 +451,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
if (err)
goto give_sigsegv;
- err |= ia32_setup_sigcontext(&frame->sc, &frame->fpstate, regs,
- set->sig[0]);
+ err |= ia32_setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]);
if (err)
goto give_sigsegv;
@@ -522,6 +515,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
struct rt_sigframe __user *frame;
void __user *restorer;
int err = 0;
+ void __user *fpstate = NULL;
/* __copy_to_user optimizes that into a single 8 byte store */
static const struct {
@@ -537,7 +531,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
0,
};
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -550,13 +544,16 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
goto give_sigsegv;
/* Create the ucontext. */
- err |= __put_user(0, &frame->uc.uc_flags);
+ if (cpu_has_xsave)
+ err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
+ else
+ err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
+ err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index dac24c4390d..c9be69fedb7 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -38,7 +38,7 @@ obj-y += tsc.o io_delay.o rtc.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o
obj-y += process.o
-obj-y += i387.o
+obj-y += i387.o xsave.o
obj-y += ptrace.o
obj-y += ds.o
obj-$(CONFIG_X86_32) += tls.o
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 0785b3c8d04..c63ec65f484 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -739,9 +739,20 @@ void __cpuinit cpu_init(void)
/*
* Force FPU initialization:
*/
- current_thread_info()->status = 0;
+ if (cpu_has_xsave)
+ current_thread_info()->status = TS_XSAVE;
+ else
+ current_thread_info()->status = 0;
clear_used_math();
mxcsr_feature_mask_init();
+
+ /*
+ * Boot processor to setup the FP and extended state context info.
+ */
+ if (!smp_processor_id())
+ init_thread_xstate();
+
+ xsave_init();
}
#ifdef CONFIG_HOTPLUG_CPU
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index eb9ddd8efb8..45723f1fe19 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -21,9 +21,12 @@
# include <asm/sigcontext32.h>
# include <asm/user32.h>
#else
-# define save_i387_ia32 save_i387
-# define restore_i387_ia32 restore_i387
+# define save_i387_xstate_ia32 save_i387_xstate
+# define restore_i387_xstate_ia32 restore_i387_xstate
# define _fpstate_ia32 _fpstate
+# define _xstate_ia32 _xstate
+# define sig_xstate_ia32_size sig_xstate_size
+# define fx_sw_reserved_ia32 fx_sw_reserved
# define user_i387_ia32_struct user_i387_struct
# define user32_fxsr_struct user_fxsr_struct
#endif
@@ -36,6 +39,7 @@
static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu;
unsigned int xstate_size;
+unsigned int sig_xstate_ia32_size = sizeof(struct _fpstate_ia32);
static struct i387_fxsave_struct fx_scratch __cpuinitdata;
void __cpuinit mxcsr_feature_mask_init(void)
@@ -61,6 +65,11 @@ void __init init_thread_xstate(void)
return;
}
+ if (cpu_has_xsave) {
+ xsave_cntxt_init();
+ return;
+ }
+
if (cpu_has_fxsr)
xstate_size = sizeof(struct i387_fxsave_struct);
#ifdef CONFIG_X86_32
@@ -83,9 +92,19 @@ void __cpuinit fpu_init(void)
write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */
+ /*
+ * Boot processor to setup the FP and extended state context info.
+ */
+ if (!smp_processor_id())
+ init_thread_xstate();
+ xsave_init();
+
mxcsr_feature_mask_init();
/* clean state in init */
- current_thread_info()->status = 0;
+ if (cpu_has_xsave)
+ current_thread_info()->status = TS_XSAVE;
+ else
+ current_thread_info()->status = 0;
clear_used_math();
}
#endif /* CONFIG_X86_64 */
@@ -195,6 +214,13 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
*/
target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask;
+ /*
+ * update the header bits in the xsave header, indicating the
+ * presence of FP and SSE state.
+ */
+ if (cpu_has_xsave)
+ target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE;
+
return ret;
}
@@ -395,6 +421,12 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset,
if (!ret)
convert_to_fxsr(target, &env);
+ /*
+ * update the header bit in the xsave header, indicating the
+ * presence of FP.
+ */
+ if (cpu_has_xsave)
+ target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FP;
return ret;
}
@@ -407,7 +439,6 @@ static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf)
struct task_struct *tsk = current;
struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave;
- unlazy_fpu(tsk);
fp->status = fp->swd;
if (__copy_to_user(buf, fp, sizeof(struct i387_fsave_struct)))
return -1;
@@ -421,8 +452,6 @@ static int save_i387_fxsave(struct _fpstate_ia32 __user *buf)
struct user_i387_ia32_struct env;
int err = 0;
- unlazy_fpu(tsk);
-
convert_from_fxsr(&env, tsk);
if (__copy_to_user(buf, &env, sizeof(env)))
return -1;
@@ -432,16 +461,40 @@ static int save_i387_fxsave(struct _fpstate_ia32 __user *buf)
if (err)
return -1;
- if (__copy_to_user(&buf->_fxsr_env[0], fx,
- sizeof(struct i387_fxsave_struct)))
+ if (__copy_to_user(&buf->_fxsr_env[0], fx, xstate_size))
return -1;
return 1;
}
-int save_i387_ia32(struct _fpstate_ia32 __user *buf)
+static int save_i387_xsave(void __user *buf)
+{
+ struct _fpstate_ia32 __user *fx = buf;
+ int err = 0;
+
+ if (save_i387_fxsave(fx) < 0)
+ return -1;
+
+ err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved_ia32,
+ sizeof(struct _fpx_sw_bytes));
+ err |= __put_user(FP_XSTATE_MAGIC2,
+ (__u32 __user *) (buf + sig_xstate_ia32_size
+ - FP_XSTATE_MAGIC2_SIZE));
+ if (err)
+ return -1;
+
+ return 1;
+}
+
+int save_i387_xstate_ia32(void __user *buf)
{
+ struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf;
+ struct task_struct *tsk = current;
+
if (!used_math())
return 0;
+
+ if (!access_ok(VERIFY_WRITE, buf, sig_xstate_ia32_size))
+ return -EACCES;
/*
* This will cause a "finit" to be triggered by the next
* attempted FPU operation by the 'current' process.
@@ -451,13 +504,17 @@ int save_i387_ia32(struct _fpstate_ia32 __user *buf)
if (!HAVE_HWFP) {
return fpregs_soft_get(current, NULL,
0, sizeof(struct user_i387_ia32_struct),
- NULL, buf) ? -1 : 1;
+ NULL, fp) ? -1 : 1;
}
+ unlazy_fpu(tsk);
+
+ if (cpu_has_xsave)
+ return save_i387_xsave(fp);
if (cpu_has_fxsr)
- return save_i387_fxsave(buf);
+ return save_i387_fxsave(fp);
else
- return save_i387_fsave(buf);
+ return save_i387_fsave(fp);
}
static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf)
@@ -468,14 +525,15 @@ static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf)
sizeof(struct i387_fsave_struct));
}
-static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf)
+static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf,
+ unsigned int size)
{
struct task_struct *tsk = current;
struct user_i387_ia32_struct env;
int err;
err = __copy_from_user(&tsk->thread.xstate->fxsave, &buf->_fxsr_env[0],
- sizeof(struct i387_fxsave_struct));
+ size);
/* mxcsr reserved bits must be masked to zero for security reasons */
tsk->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask;
if (err || __copy_from_user(&env, buf, sizeof(env)))
@@ -485,14 +543,69 @@ static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf)
return 0;
}
-int restore_i387_ia32(struct _fpstate_ia32 __user *buf)
+static int restore_i387_xsave(void __user *buf)
+{
+ struct _fpx_sw_bytes fx_sw_user;
+ struct _fpstate_ia32 __user *fx_user =
+ ((struct _fpstate_ia32 __user *) buf);
+ struct i387_fxsave_struct __user *fx =
+ (struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0];
+ struct xsave_hdr_struct *xsave_hdr =
+ &current->thread.xstate->xsave.xsave_hdr;
+ u64 mask;
+ int err;
+
+ if (check_for_xstate(fx, buf, &fx_sw_user))
+ goto fx_only;
+
+ mask = fx_sw_user.xstate_bv;
+
+ err = restore_i387_fxsave(buf, fx_sw_user.xstate_size);
+
+ xsave_hdr->xstate_bv &= pcntxt_mask;
+ /*
+ * These bits must be zero.
+ */
+ xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0;
+
+ /*
+ * Init the state that is not present in the memory layout
+ * and enabled by the OS.
+ */
+ mask = ~(pcntxt_mask & ~mask);
+ xsave_hdr->xstate_bv &= mask;
+
+ return err;
+fx_only:
+ /*
+ * Couldn't find the extended state information in the memory
+ * layout. Restore the FP/SSE and init the other extended state
+ * enabled by the OS.
+ */
+ xsave_hdr->xstate_bv = XSTATE_FPSSE;
+ return restore_i387_fxsave(buf, sizeof(struct i387_fxsave_struct));
+}
+
+int restore_i387_xstate_ia32(void __user *buf)
{
int err;
struct task_struct *tsk = current;
+ struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf;
if (HAVE_HWFP)
clear_fpu(tsk);
+ if (!buf) {
+ if (used_math()) {
+ clear_fpu(tsk);
+ clear_used_math();
+ }
+
+ return 0;
+ } else
+ if (!access_ok(VERIFY_READ, buf, sig_xstate_ia32_size))
+ return -EACCES;
+
if (!used_math()) {
err = init_fpu(tsk);
if (err)
@@ -500,14 +613,17 @@ int restore_i387_ia32(struct _fpstate_ia32 __user *buf)
}
if (HAVE_HWFP) {
- if (cpu_has_fxsr)
- err = restore_i387_fxsave(buf);
+ if (cpu_has_xsave)
+ err = restore_i387_xsave(buf);
+ else if (cpu_has_fxsr)
+ err = restore_i387_fxsave(fp, sizeof(struct
+ i387_fxsave_struct));
else
- err = restore_i387_fsave(buf);
+ err = restore_i387_fsave(fp);
} else {
err = fpregs_soft_set(current, NULL,
0, sizeof(struct user_i387_ia32_struct),
- NULL, buf) != 0;
+ NULL, fp) != 0;
}
set_used_math();
diff --git a/arch/x86/kernel/sigframe.h b/arch/x86/kernel/sigframe.h
index 72bbb519d2d..6dd7e2b70a4 100644
--- a/arch/x86/kernel/sigframe.h
+++ b/arch/x86/kernel/sigframe.h
@@ -3,9 +3,18 @@ struct sigframe {
char __user *pretcode;
int sig;
struct sigcontext sc;
- struct _fpstate fpstate;
+ /*
+ * fpstate is unused. fpstate is moved/allocated after
+ * retcode[] below. This movement allows to have the FP state and the
+ * future state extensions (xsave) stay together.
+ * And at the same time retaining the unused fpstate, prevents changing
+ * the offset of extramask[] in the sigframe and thus prevent any
+ * legacy application accessing/modifying it.
+ */
+ struct _fpstate fpstate_unused;
unsigned long extramask[_NSIG_WORDS-1];
char retcode[8];
+ /* fp state follows here */
};
struct rt_sigframe {
@@ -15,13 +24,14 @@ struct rt_sigframe {
void __user *puc;
struct siginfo info;
struct ucontext uc;
- struct _fpstate fpstate;
char retcode[8];
+ /* fp state follows here */
};
#else
struct rt_sigframe {
char __user *pretcode;
struct ucontext uc;
struct siginfo info;
+ /* fp state follows here */
};
#endif
diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 0c727f64e79..8d380b699c0 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -160,28 +160,14 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
}
{
- struct _fpstate __user *buf;
+ void __user *buf;
err |= __get_user(buf, &sc->fpstate);
- if (buf) {
- if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
- goto badframe;
- err |= restore_i387(buf);
- } else {
- struct task_struct *me = current;
-
- if (used_math()) {
- clear_fpu(me);
- clear_used_math();
- }
- }
+ err |= restore_i387_xstate(buf);
}
err |= __get_user(*pax, &sc->ax);
return err;
-
-badframe:
- return 1;
}
asmlinkage unsigned long sys_sigreturn(unsigned long __unused)
@@ -263,7 +249,7 @@ badframe:
* Set up a signal frame.
*/
static int
-setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
+setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
struct pt_regs *regs, unsigned long mask)
{
int tmp, err = 0;
@@ -290,7 +276,7 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
err |= __put_user(regs->sp, &sc->sp_at_signal);
err |= __put_user(regs->ss, (unsigned int __user *)&sc->ss);
- tmp = save_i387(fpstate);
+ tmp = save_i387_xstate(fpstate);
if (tmp < 0)
err = 1;
else
@@ -307,7 +293,8 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
* Determine which stack to use..
*/
static inline void __user *
-get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
+ void **fpstate)
{
unsigned long sp;
@@ -333,6 +320,11 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
sp = (unsigned long) ka->sa.sa_restorer;
}
+ if (used_math()) {
+ sp = sp - sig_xstate_size;
+ *fpstate = (struct _fpstate *) sp;
+ }
+
sp -= frame_size;
/*
* Align the stack pointer according to the i386 ABI,
@@ -351,8 +343,9 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
void __user *restorer;
int err = 0;
int usig;
+ void __user *fpstate = NULL;
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -367,7 +360,7 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
if (err)
goto give_sigsegv;
- err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
+ err = setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]);
if (err)
goto give_sigsegv;
@@ -428,8 +421,9 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
void __user *restorer;
int err = 0;
int usig;
+ void __user *fpstate = NULL;
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -448,13 +442,16 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
goto give_sigsegv;
/* Create the ucontext. */
- err |= __put_user(0, &frame->uc.uc_flags);
+ if (cpu_has_xsave)
+ err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
+ else
+ err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index 2f146405005..4665b598a37 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -55,69 +55,6 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
}
/*
- * Signal frame handlers.
- */
-
-static inline int save_i387(struct _fpstate __user *buf)
-{
- struct task_struct *tsk = current;
- int err = 0;
-
- BUILD_BUG_ON(sizeof(struct user_i387_struct) !=
- sizeof(tsk->thread.xstate->fxsave));
-
- if ((unsigned long)buf % 16)
- printk("save_i387: bad fpstate %p\n", buf);
-
- if (!used_math())
- return 0;
- clear_used_math(); /* trigger finit */
- if (task_thread_info(tsk)->status & TS_USEDFPU) {
- err = save_i387_checking((struct i387_fxsave_struct __user *)
- buf);
- if (err)
- return err;
- task_thread_info(tsk)->status &= ~TS_USEDFPU;
- stts();
- } else {
- if (__copy_to_user(buf, &tsk->thread.xstate->fxsave,
- sizeof(struct i387_fxsave_struct)))
- return -1;
- }
- return 1;
-}
-
-/*
- * This restores directly out of user space. Exceptions are handled.
- */
-static inline int restore_i387(struct _fpstate __user *buf)
-{
- struct task_struct *tsk = current;
- int err;
-
- if (!used_math()) {
- err = init_fpu(tsk);
- if (err)
- return err;
- }
-
- if (!(task_thread_info(current)->status & TS_USEDFPU)) {
- clts();
- task_thread_info(current)->status |= TS_USEDFPU;
- }
- err = restore_fpu_checking((__force struct i387_fxsave_struct *)buf);
- if (unlikely(err)) {
- /*
- * Encountered an error while doing the restore from the
- * user buffer, clear the fpu state.
- */
- clear_fpu(tsk);
- clear_used_math();
- }
- return err;
-}
-
-/*
* Do a signal return; undo the signal stack.
*/
static int
@@ -161,25 +98,11 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
{
struct _fpstate __user * buf;
err |= __get_user(buf, &sc->fpstate);
-
- if (buf) {
- if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
- goto badframe;
- err |= restore_i387(buf);
- } else {
- struct task_struct *me = current;
- if (used_math()) {
- clear_fpu(me);
- clear_used_math();
- }
- }
+ err |= restore_i387_xstate(buf);
}
err |= __get_user(*pax, &sc->ax);
return err;
-
-badframe:
- return 1;
}
asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
@@ -270,26 +193,23 @@ get_stack(struct k_sigaction *ka, struct pt_regs *regs, unsigned long size)
sp = current->sas_ss_sp + current->sas_ss_size;
}
- return (void __user *)round_down(sp - size, 16);
+ return (void __user *)round_down(sp - size, 64);
}
static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *set, struct pt_regs * regs)
{
struct rt_sigframe __user *frame;
- struct _fpstate __user *fp = NULL;
+ void __user *fp = NULL;
int err = 0;
struct task_struct *me = current;
if (used_math()) {
- fp = get_stack(ka, regs, sizeof(struct _fpstate));
+ fp = get_stack(ka, regs, sig_xstate_size);
frame = (void __user *)round_down(
(unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
- if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate)))
- goto give_sigsegv;
-
- if (save_i387(fp) < 0)
+ if (save_i387_xstate(fp) < 0)
err |= -1;
} else
frame = get_stack(ka, regs, sizeof(struct rt_sigframe)) - 8;
@@ -304,7 +224,10 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
}
/* Create the ucontext. */
- err |= __put_user(0, &frame->uc.uc_flags);
+ if (cpu_has_xsave)
+ err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
+ else
+ err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->sp),
diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
index 03df8e45e5a..da5a5964fcc 100644
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps_32.c
@@ -1228,7 +1228,6 @@ void __init trap_init(void)
set_bit(SYSCALL_VECTOR, used_vectors);
- init_thread_xstate();
/*
* Should be a barrier for any external CPU state:
*/
diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index 513caaca711..38eb76156a4 100644
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -1134,7 +1134,7 @@ asmlinkage void math_state_restore(void)
/*
* Paranoid restore. send a SIGSEGV if we fail to restore the state.
*/
- if (unlikely(restore_fpu_checking(&me->thread.xstate->fxsave))) {
+ if (unlikely(restore_fpu_checking(me))) {
stts();
force_sig(SIGSEGV, me);
return;
@@ -1173,10 +1173,6 @@ void __init trap_init(void)
set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
#endif
/*
- * initialize the per thread extended state:
- */
- init_thread_xstate();
- /*
* Should be a barrier for any external CPU state:
*/
cpu_init();
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
new file mode 100644
index 00000000000..07713d64deb
--- /dev/null
+++ b/arch/x86/kernel/xsave.c
@@ -0,0 +1,316 @@
+/*
+ * xsave/xrstor support.
+ *
+ * Author: Suresh Siddha <suresh.b.siddha@intel.com>
+ */
+#include <linux/bootmem.h>
+#include <linux/compat.h>
+#include <asm/i387.h>
+#ifdef CONFIG_IA32_EMULATION
+#include <asm/sigcontext32.h>
+#endif
+#include <asm/xcr.h>
+
+/*
+ * Supported feature mask by the CPU and the kernel.
+ */
+u64 pcntxt_mask;
+
+struct _fpx_sw_bytes fx_sw_reserved;
+#ifdef CONFIG_IA32_EMULATION
+struct _fpx_sw_bytes fx_sw_reserved_ia32;
+#endif
+
+/*
+ * Check for the presence of extended state information in the
+ * user fpstate pointer in the sigcontext.
+ */
+int check_for_xstate(struct i387_fxsave_struct __user *buf,
+ void __user *fpstate,
+ struct _fpx_sw_bytes *fx_sw_user)
+{
+ int min_xstate_size = sizeof(struct i387_fxsave_struct) +
+ sizeof(struct xsave_hdr_struct);
+ unsigned int magic2;
+ int err;
+
+ err = __copy_from_user(fx_sw_user, &buf->sw_reserved[0],
+ sizeof(struct _fpx_sw_bytes));
+
+ if (err)
+ return err;
+
+ /*
+ * First Magic check failed.
+ */
+ if (fx_sw_user->magic1 != FP_XSTATE_MAGIC1)
+ return -1;
+
+ /*
+ * Check for error scenarios.
+ */
+ if (fx_sw_user->xstate_size < min_xstate_size ||
+ fx_sw_user->xstate_size > xstate_size ||
+ fx_sw_user->xstate_size > fx_sw_user->extended_size)
+ return -1;
+
+ err = __get_user(magic2, (__u32 *) (((void *)fpstate) +
+ fx_sw_user->extended_size -
+ FP_XSTATE_MAGIC2_SIZE));
+ /*
+ * Check for the presence of second magic word at the end of memory
+ * layout. This detects the case where the user just copied the legacy
+ * fpstate layout with out copying the extended state information
+ * in the memory layout.
+ */
+ if (err || magic2 != FP_XSTATE_MAGIC2)
+ return -1;
+
+ return 0;
+}
+
+#ifdef CONFIG_X86_64
+/*
+ * Signal frame handlers.
+ */
+
+int save_i387_xstate(void __user *buf)
+{
+ struct task_struct *tsk = current;
+ int err = 0;
+
+ if (!access_ok(VERIFY_WRITE, buf, sig_xstate_size))
+ return -EACCES;
+
+ BUG_ON(sig_xstate_size < xstate_size);
+
+ if ((unsigned long)buf % 64)
+ printk("save_i387_xstate: bad fpstate %p\n", buf);
+
+ if (!used_math())
+ return 0;
+ clear_used_math(); /* trigger finit */
+ if (task_thread_info(tsk)->status & TS_USEDFPU) {
+ /*
+ * Start with clearing the user buffer. This will present a
+ * clean context for the bytes not touched by the fxsave/xsave.
+ */
+ __clear_user(buf, sig_xstate_size);
+
+ if (task_thread_info(tsk)->status & TS_XSAVE)
+ err = xsave_user(buf);
+ else
+ err = fxsave_user(buf);
+
+ if (err)
+ return err;
+ task_thread_info(tsk)->status &= ~TS_USEDFPU;
+ stts();
+ } else {
+ if (__copy_to_user(buf, &tsk->thread.xstate->fxsave,
+ xstate_size))
+ return -1;
+ }
+
+ if (task_thread_info(tsk)->status & TS_XSAVE) {
+ struct _fpstate __user *fx = buf;
+
+ err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved,
+ sizeof(struct _fpx_sw_bytes));
+
+ err |= __put_user(FP_XSTATE_MAGIC2,
+ (__u32 __user *) (buf + sig_xstate_size
+ - FP_XSTATE_MAGIC2_SIZE));
+ }
+
+ return 1;
+}
+
+/*
+ * Restore the extended state if present. Otherwise, restore the FP/SSE
+ * state.
+ */
+int restore_user_xstate(void __user *buf)
+{
+ struct _fpx_sw_bytes fx_sw_user;
+ u64 mask;
+ int err;
+
+ if (((unsigned long)buf % 64) ||
+ check_for_xstate(buf, buf, &fx_sw_user))
+ goto fx_only;
+
+ mask = fx_sw_user.xstate_bv;
+
+ /*
+ * restore the state passed by the user.
+ */
+ err = xrestore_user(buf, mask);
+ if (err)
+ return err;
+
+ /*
+ * init the state skipped by the user.
+ */
+ mask = pcntxt_mask & ~mask;
+
+ xrstor_state(init_xstate_buf, mask);
+
+ return 0;
+
+fx_only:
+ /*
+ * couldn't find the extended state information in the
+ * memory layout. Restore just the FP/SSE and init all
+ * the other extended state.
+ */
+ xrstor_state(init_xstate_buf, pcntxt_mask & ~XSTATE_FPSSE);
+ return fxrstor_checking((__force struct i387_fxsave_struct *)buf);
+}
+
+/*
+ * This restores directly out of user space. Exceptions are handled.
+ */
+int restore_i387_xstate(void __user *buf)
+{
+ struct task_struct *tsk = current;
+ int err = 0;
+
+ if (!buf) {
+ if (used_math())
+ goto clear;
+ return 0;
+ } else
+ if (!access_ok(VERIFY_READ, buf, sig_xstate_size))
+ return -EACCES;
+
+ if (!used_math()) {
+ err = init_fpu(tsk);
+ if (err)
+ return err;
+ }
+
+ if (!(task_thread_info(current)->status & TS_USEDFPU)) {
+ clts();
+ task_thread_info(current)->status |= TS_USEDFPU;
+ }
+ if (task_thread_info(tsk)->status & TS_XSAVE)
+ err = restore_user_xstate(buf);
+ else
+ err = fxrstor_checking((__force struct i387_fxsave_struct *)
+ buf);
+ if (unlikely(err)) {
+ /*
+ * Encountered an error while doing the restore from the
+ * user buffer, clear the fpu state.
+ */
+clear:
+ clear_fpu(tsk);
+ clear_used_math();
+ }
+ return err;
+}
+#endif
+
+/*
+ * Prepare the SW reserved portion of the fxsave memory layout, indicating
+ * the presence of the extended state information in the memory layout
+ * pointed by the fpstate pointer in the sigcontext.
+ * This will be saved when ever the FP and extended state context is
+ * saved on the user stack during the signal handler delivery to the user.
+ */
+void prepare_fx_sw_frame(void)
+{
+ int size_extended = (xstate_size - sizeof(struct i387_fxsave_struct)) +
+ FP_XSTATE_MAGIC2_SIZE;
+
+ sig_xstate_size = sizeof(struct _fpstate) + size_extended;
+
+#ifdef CONFIG_IA32_EMULATION
+ sig_xstate_ia32_size = sizeof(struct _fpstate_ia32) + size_extended;
+#endif
+
+ memset(&fx_sw_reserved, 0, sizeof(fx_sw_reserved));
+
+ fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;
+ fx_sw_reserved.extended_size = sig_xstate_size;
+ fx_sw_reserved.xstate_bv = pcntxt_mask;
+ fx_sw_reserved.xstate_size = xstate_size;
+#ifdef CONFIG_IA32_EMULATION
+ memcpy(&fx_sw_reserved_ia32, &fx_sw_reserved,
+ sizeof(struct _fpx_sw_bytes));
+ fx_sw_reserved_ia32.extended_size = sig_xstate_ia32_size;
+#endif
+}
+
+/*
+ * Represents init state for the supported extended state.
+ */
+struct xsave_struct *init_xstate_buf;
+
+#ifdef CONFIG_X86_64
+unsigned int sig_xstate_size = sizeof(struct _fpstate);
+#endif
+
+/*
+ * Enable the extended processor state save/restore feature
+ */
+void __cpuinit xsave_init(void)
+{
+ if (!cpu_has_xsave)
+ return;
+
+ set_in_cr4(X86_CR4_OSXSAVE);
+
+ /*
+ * Enable all the features that the HW is capable of
+ * and the Linux kernel is aware of.
+ */
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
+}
+
+/*
+ * setup the xstate image representing the init state
+ */
+void setup_xstate_init(void)
+{
+ init_xstate_buf = alloc_bootmem(xstate_size);
+ init_xstate_buf->i387.mxcsr = MXCSR_DEFAULT;
+}
+
+/*
+ * Enable and initialize the xsave feature.
+ */
+void __init xsave_cntxt_init(void)
+{
+ unsigned int eax, ebx, ecx, edx;
+
+ cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);
+ pcntxt_mask = eax + ((u64)edx << 32);
+
+ if ((pcntxt_mask & XSTATE_FPSSE) != XSTATE_FPSSE) {
+ printk(KERN_ERR "FP/SSE not shown under xsave features 0x%llx\n",
+ pcntxt_mask);
+ BUG();
+ }
+
+ /*
+ * for now OS knows only about FP/SSE
+ */
+ pcntxt_mask = pcntxt_mask & XCNTXT_MASK;
+ xsave_init();
+
+ /*
+ * Recompute the context size for enabled features
+ */
+ cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);
+ xstate_size = ebx;
+
+ prepare_fx_sw_frame();
+
+ setup_xstate_init();
+
+ printk(KERN_INFO "xsave/xrstor: enabled xstate_bv 0x%llx, "
+ "cntxt size 0x%x\n",
+ pcntxt_mask, xstate_size);
+}
diff --git a/arch/x86/power/cpu_32.c b/arch/x86/power/cpu_32.c
index d3e083dea72..274d06082f4 100644
--- a/arch/x86/power/cpu_32.c
+++ b/arch/x86/power/cpu_32.c
@@ -11,6 +11,7 @@
#include <linux/suspend.h>
#include <asm/mtrr.h>
#include <asm/mce.h>
+#include <asm/xcr.h>
static struct saved_context saved_context;
@@ -126,6 +127,12 @@ static void __restore_processor_state(struct saved_context *ctxt)
if (boot_cpu_has(X86_FEATURE_SEP))
enable_sep_cpu();
+ /*
+ * restore XCR0 for xsave capable cpu's.
+ */
+ if (cpu_has_xsave)
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
+
fix_processor_context();
do_fpu_end();
mtrr_ap_init();
diff --git a/arch/x86/power/cpu_64.c b/arch/x86/power/cpu_64.c
index 66bdfb591fd..e3b6cf70d62 100644
--- a/arch/x86/power/cpu_64.c
+++ b/arch/x86/power/cpu_64.c
@@ -14,6 +14,7 @@
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/mtrr.h>
+#include <asm/xcr.h>
static void fix_processor_context(void);
@@ -122,6 +123,12 @@ static void __restore_processor_state(struct saved_context *ctxt)
wrmsrl(MSR_GS_BASE, ctxt->gs_base);
wrmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
+ /*
+ * restore XCR0 for xsave capable cpu's.
+ */
+ if (cpu_has_xsave)
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
+
fix_processor_context();
do_fpu_end();
diff --git a/include/asm-x86/i387.h b/include/asm-x86/i387.h
index 1ecdc3ed96e..9ba862a4eac 100644
--- a/include/asm-x86/i387.h
+++ b/include/asm-x86/i387.h
@@ -19,7 +19,9 @@
#include <asm/sigcontext.h>
#include <asm/user.h>
#include <asm/uaccess.h>
+#include <asm/xsave.h>
+extern unsigned int sig_xstate_size;
extern void fpu_init(void);
extern void mxcsr_feature_mask_init(void);
extern int init_fpu(struct task_struct *child);
@@ -31,12 +33,18 @@ extern user_regset_active_fn fpregs_active, xfpregs_active;
extern user_regset_get_fn fpregs_get, xfpregs_get, fpregs_soft_get;
extern user_regset_set_fn fpregs_set, xfpregs_set, fpregs_soft_set;
+extern struct _fpx_sw_bytes fx_sw_reserved;
#ifdef CONFIG_IA32_EMULATION
+extern unsigned int sig_xstate_ia32_size;
+extern struct _fpx_sw_bytes fx_sw_reserved_ia32;
struct _fpstate_ia32;
-extern int save_i387_ia32(struct _fpstate_ia32 __user *buf);
-extern int restore_i387_ia32(struct _fpstate_ia32 __user *buf);
+struct _xstate_ia32;
+extern int save_i387_xstate_ia32(void __user *buf);
+extern int restore_i387_xstate_ia32(void __user *buf);
#endif
+#define X87_FSW_ES (1 << 7) /* Exception Summary */
+
#ifdef CONFIG_X86_64
/* Ignore delayed exceptions from user space */
@@ -47,7 +55,7 @@ static inline void tolerant_fwait(void)
_ASM_EXTABLE(1b, 2b));
}
-static inline int restore_fpu_checking(struct i387_fxsave_struct *fx)
+static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
{
int err;
@@ -67,15 +75,31 @@ static inline int restore_fpu_checking(struct i387_fxsave_struct *fx)
return err;
}
-#define X87_FSW_ES (1 << 7) /* Exception Summary */
+static inline int restore_fpu_checking(struct task_struct *tsk)
+{
+ if (task_thread_info(tsk)->status & TS_XSAVE)
+ return xrstor_checking(&tsk->thread.xstate->xsave);
+ else
+ return fxrstor_checking(&tsk->thread.xstate->fxsave);
+}
/* AMD CPUs don't save/restore FDP/FIP/FOP unless an exception
is pending. Clear the x87 state here by setting it to fixed
values. The kernel data segment can be sometimes 0 and sometimes
new user value. Both should be ok.
Use the PDA as safe address because it should be already in L1. */
-static inline void clear_fpu_state(struct i387_fxsave_struct *fx)
+static inline void clear_fpu_state(struct task_struct *tsk)
{
+ struct xsave_struct *xstate = &tsk->thread.xstate->xsave;
+ struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave;
+
+ /*
+ * xsave header may indicate the init state of the FP.
+ */
+ if ((task_thread_info(tsk)->status & TS_XSAVE) &&
+ !(xstate->xsave_hdr.xstate_bv & XSTATE_FP))
+ return;
+
if (unlikely(fx->swd & X87_FSW_ES))
asm volatile("fnclex");
alternative_input(ASM_NOP8 ASM_NOP2,
@@ -84,7 +108,7 @@ static inline void clear_fpu_state(struct i387_fxsave_struct *fx)
X86_FEATURE_FXSAVE_LEAK);
}
-static inline int save_i387_checking(struct i387_fxsave_struct __user *fx)
+static inline int fxsave_user(struct i387_fxsave_struct __user *fx)
{
int err;
@@ -108,7 +132,7 @@ static inline int save_i387_checking(struct i387_fxsave_struct __user *fx)
return err;
}
-static inline void __save_init_fpu(struct task_struct *tsk)
+static inline void fxsave(struct task_struct *tsk)
{
/* Using "rex64; fxsave %0" is broken because, if the memory operand
uses any extended registers for addressing, a second REX prefix
@@ -133,7 +157,16 @@ static inline void __save_init_fpu(struct task_struct *tsk)
: "=m" (tsk->thread.xstate->fxsave)
: "cdaSDb" (&tsk->thread.xstate->fxsave));
#endif
- clear_fpu_state(&tsk->thread.xstate->fxsave);
+}
+
+static inline void __save_init_fpu(struct task_struct *tsk)
+{
+ if (task_thread_info(tsk)->status & TS_XSAVE)
+ xsave(tsk);
+ else
+ fxsave(tsk);
+
+ clear_fpu_state(tsk);
task_thread_info(tsk)->status &= ~TS_USEDFPU;
}
@@ -148,6 +181,10 @@ static inline void tolerant_fwait(void)
static inline void restore_fpu(struct task_struct *tsk)
{
+ if (task_thread_info(tsk)->status & TS_XSAVE) {
+ xrstor_checking(&tsk->thread.xstate->xsave);
+ return;
+ }
/*
* The "nop" is needed to make the instructions the same
* length.
@@ -173,6 +210,27 @@ static inline void restore_fpu(struct task_struct *tsk)
*/
static inline void __save_init_fpu(struct task_struct *tsk)
{
+ if (task_thread_info(tsk)->status & TS_XSAVE) {
+ struct xsave_struct *xstate = &tsk->thread.xstate->xsave;
+ struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave;
+
+ xsave(tsk);
+
+ /*
+ * xsave header may indicate the init state of the FP.
+ */
+ if (!(xstate->xsave_hdr.xstate_bv & XSTATE_FP))
+ goto end;
+
+ if (unlikely(fx->swd & X87_FSW_ES))
+ asm volatile("fnclex");
+
+ /*
+ * we can do a simple return here or be paranoid :)
+ */
+ goto clear_state;
+ }
+
/* Use more nops than strictly needed in case the compiler
varies code */
alternative_input(
@@ -182,6 +240,7 @@ static inline void __save_init_fpu(struct task_struct *tsk)
X86_FEATURE_FXSR,
[fx] "m" (tsk->thread.xstate->fxsave),
[fsw] "m" (tsk->thread.xstate->fxsave.swd) : "memory");
+clear_state:
/* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
is pending. Clear the x87 state here by setting it to fixed
values. safe_address is a random variable that should be in L1 */
@@ -191,16 +250,17 @@ static inline void __save_init_fpu(struct task_struct *tsk)
"fildl %[addr]", /* set F?P to defined value */
X86_FEATURE_FXSAVE_LEAK,
[addr] "m" (safe_address));
+end:
task_thread_info(tsk)->status &= ~TS_USEDFPU;
}
+#endif /* CONFIG_X86_64 */
+
/*
* Signal frame handlers...
*/
-extern int save_i387(struct _fpstate __user *buf);
-extern int restore_i387(struct _fpstate __user *buf);
-
-#endif /* CONFIG_X86_64 */
+extern int save_i387_xstate(void __user *buf);
+extern int restore_i387_xstate(void __user *buf);
static inline void __unlazy_fpu(struct task_struct *tsk)
{
diff --git a/include/asm-x86/processor-flags.h b/include/asm-x86/processor-flags.h
index 5dd79774f69..dc5f0712f9f 100644
--- a/include/asm-x86/processor-flags.h
+++ b/include/asm-x86/processor-flags.h
@@ -59,6 +59,7 @@
#define X86_CR4_OSFXSR 0x00000200 /* enable fast FPU save and restore */
#define X86_CR4_OSXMMEXCPT 0x00000400 /* enable unmasked SSE exceptions */
#define X86_CR4_VMXE 0x00002000 /* enable VMX virtualization */
+#define X86_CR4_OSXSAVE 0x00040000 /* enable xsave and xrestore */
/*
* x86-64 Task Priority Register, CR8
diff --git a/include/asm-x86/processor.h b/include/asm-x86/processor.h
index 10471cfab14..df03c98e38d 100644
--- a/include/asm-x86/processor.h
+++ b/include/asm-x86/processor.h
@@ -326,7 +326,12 @@ struct i387_fxsave_struct {
/* 16*16 bytes for each XMM-reg = 256 bytes: */
u32 xmm_space[64];
- u32 padding[24];
+ u32 padding[12];
+
+ union {
+ u32 padding1[12];
+ u32 sw_reserved[12];
+ };
} __attribute__((aligned(16)));
@@ -350,10 +355,23 @@ struct i387_soft_struct {
u32 entry_eip;
};
+struct xsave_hdr_struct {
+ u64 xstate_bv;
+ u64 reserved1[2];
+ u64 reserved2[5];
+} __attribute__((packed));
+
+struct xsave_struct {
+ struct i387_fxsave_struct i387;
+ struct xsave_hdr_struct xsave_hdr;
+ /* new processor state extensions will go here */
+} __attribute__ ((packed, aligned (64)));
+
union thread_xstate {
struct i387_fsave_struct fsave;
struct i387_fxsave_struct fxsave;
struct i387_soft_struct soft;
+ struct xsave_struct xsave;
};
#ifdef CONFIG_X86_64
diff --git a/include/asm-x86/sigcontext.h b/include/asm-x86/sigcontext.h
index 24879c85b29..ee813f4fe5d 100644
--- a/include/asm-x86/sigcontext.h
+++ b/include/asm-x86/sigcontext.h
@@ -4,6 +4,40 @@
#include <linux/compiler.h>
#include <asm/types.h>
+#define FP_XSTATE_MAGIC1 0x46505853U
+#define FP_XSTATE_MAGIC2 0x46505845U
+#define FP_XSTATE_MAGIC2_SIZE sizeof(FP_XSTATE_MAGIC2)
+
+/*
+ * bytes 464..511 in the current 512byte layout of fxsave/fxrstor frame
+ * are reserved for SW usage. On cpu's supporting xsave/xrstor, these bytes
+ * are used to extended the fpstate pointer in the sigcontext, which now
+ * includes the extended state information along with fpstate information.
+ *
+ * Presence of FP_XSTATE_MAGIC1 at the beginning of this SW reserved
+ * area and FP_XSTATE_MAGIC2 at the end of memory layout
+ * (extended_size - FP_XSTATE_MAGIC2_SIZE) indicates the presence of the
+ * extended state information in the memory layout pointed by the fpstate
+ * pointer in sigcontext.
+ */
+struct _fpx_sw_bytes {
+ __u32 magic1; /* FP_XSTATE_MAGIC1 */
+ __u32 extended_size; /* total size of the layout referred by
+ * fpstate pointer in the sigcontext.
+ */
+ __u64 xstate_bv;
+ /* feature bit mask (including fp/sse/extended
+ * state) that is present in the memory
+ * layout.
+ */
+ __u32 xstate_size; /* actual xsave state size, based on the
+ * features saved in the layout.
+ * 'extended_size' will be greater than
+ * 'xstate_size'.
+ */
+ __u32 padding[7]; /* for future use. */
+};
+
#ifdef __i386__
/*
* As documented in the iBCS2 standard..
@@ -53,7 +87,13 @@ struct _fpstate {
unsigned long reserved;
struct _fpxreg _fxsr_st[8]; /* FXSR FPU reg data is ignored */
struct _xmmreg _xmm[8];
- unsigned long padding[56];
+ unsigned long padding1[44];
+
+ union {
+ unsigned long padding2[12];
+ struct _fpx_sw_bytes sw_reserved; /* represents the extended
+ * state info */
+ };
};
#define X86_FXSR_MAGIC 0x0000
@@ -79,7 +119,15 @@ struct sigcontext {
unsigned long flags;
unsigned long sp_at_signal;
unsigned short ss, __ssh;
- struct _fpstate __user *fpstate;
+
+ /*
+ * fpstate is really (struct _fpstate *) or (struct _xstate *)
+ * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
+ * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
+ * of extended memory layout. See comments at the defintion of
+ * (struct _fpx_sw_bytes)
+ */
+ void __user *fpstate; /* zero when no FPU/extended context */
unsigned long oldmask;
unsigned long cr2;
};
@@ -130,7 +178,12 @@ struct _fpstate {
__u32 mxcsr_mask;
__u32 st_space[32]; /* 8*16 bytes for each FP-reg */
__u32 xmm_space[64]; /* 16*16 bytes for each XMM-reg */
- __u32 reserved2[24];
+ __u32 reserved2[12];
+ union {
+ __u32 reserved3[12];
+ struct _fpx_sw_bytes sw_reserved; /* represents the extended
+ * state information */
+ };
};
#ifdef __KERNEL__
@@ -161,7 +214,15 @@ struct sigcontext {
unsigned long trapno;
unsigned long oldmask;
unsigned long cr2;
- struct _fpstate __user *fpstate; /* zero when no FPU context */
+
+ /*
+ * fpstate is really (struct _fpstate *) or (struct _xstate *)
+ * depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
+ * bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
+ * of extended memory layout. See comments at the defintion of
+ * (struct _fpx_sw_bytes)
+ */
+ void __user *fpstate; /* zero when no FPU/extended context */
unsigned long reserved1[8];
};
#else /* __KERNEL__ */
@@ -202,4 +263,22 @@ struct sigcontext {
#endif /* !__i386__ */
+struct _xsave_hdr {
+ __u64 xstate_bv;
+ __u64 reserved1[2];
+ __u64 reserved2[5];
+};
+
+/*
+ * Extended state pointed by the fpstate pointer in the sigcontext.
+ * In addition to the fpstate, information encoded in the xstate_hdr
+ * indicates the presence of other extended state information
+ * supported by the processor and OS.
+ */
+struct _xstate {
+ struct _fpstate fpstate;
+ struct _xsave_hdr xstate_hdr;
+ /* new processor state extensions go here */
+};
+
#endif /* ASM_X86__SIGCONTEXT_H */
diff --git a/include/asm-x86/sigcontext32.h b/include/asm-x86/sigcontext32.h
index 4e2ec732dd0..8c347032c2f 100644
--- a/include/asm-x86/sigcontext32.h
+++ b/include/asm-x86/sigcontext32.h
@@ -40,7 +40,11 @@ struct _fpstate_ia32 {
__u32 reserved;
struct _fpxreg _fxsr_st[8];
struct _xmmreg _xmm[8]; /* It's actually 16 */
- __u32 padding[56];
+ __u32 padding[44];
+ union {
+ __u32 padding2[12];
+ struct _fpx_sw_bytes sw_reserved;
+ };
};
struct sigcontext_ia32 {
diff --git a/include/asm-x86/thread_info.h b/include/asm-x86/thread_info.h
index e64be8863b7..30586f2ee55 100644
--- a/include/asm-x86/thread_info.h
+++ b/include/asm-x86/thread_info.h
@@ -239,6 +239,7 @@ static inline struct thread_info *stack_thread_info(void)
#define TS_POLLING 0x0004 /* true if in idle loop
and not sleeping */
#define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */
+#define TS_XSAVE 0x0010 /* Use xsave/xrstor */
#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)
diff --git a/include/asm-x86/ucontext.h b/include/asm-x86/ucontext.h
index 9948dd32808..89eaa5456a7 100644
--- a/include/asm-x86/ucontext.h
+++ b/include/asm-x86/ucontext.h
@@ -1,6 +1,12 @@
#ifndef ASM_X86__UCONTEXT_H
#define ASM_X86__UCONTEXT_H
+#define UC_FP_XSTATE 0x1 /* indicates the presence of extended state
+ * information in the memory layout pointed
+ * by the fpstate pointer in the ucontext's
+ * sigcontext struct (uc_mcontext).
+ */
+
struct ucontext {
unsigned long uc_flags;
struct ucontext *uc_link;
diff --git a/include/asm-x86/xcr.h b/include/asm-x86/xcr.h
new file mode 100644
index 00000000000..f2cba4e79a2
--- /dev/null
+++ b/include/asm-x86/xcr.h
@@ -0,0 +1,49 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ * Copyright 2008 rPath, Inc. - All Rights Reserved
+ *
+ * This file is part of the Linux kernel, and is made available under
+ * the terms of the GNU General Public License version 2 or (at your
+ * option) any later version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * asm-x86/xcr.h
+ *
+ * Definitions for the eXtended Control Register instructions
+ */
+
+#ifndef _ASM_X86_XCR_H
+#define _ASM_X86_XCR_H
+
+#define XCR_XFEATURE_ENABLED_MASK 0x00000000
+
+#ifdef __KERNEL__
+# ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+
+static inline u64 xgetbv(u32 index)
+{
+ u32 eax, edx;
+
+ asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */
+ : "=a" (eax), "=d" (edx)
+ : "c" (index));
+ return eax + ((u64)edx << 32);
+}
+
+static inline void xsetbv(u32 index, u64 value)
+{
+ u32 eax = value;
+ u32 edx = value >> 32;
+
+ asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */
+ : : "a" (eax), "d" (edx), "c" (index));
+}
+
+# endif /* __ASSEMBLY__ */
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_X86_XCR_H */
diff --git a/include/asm-x86/xsave.h b/include/asm-x86/xsave.h
new file mode 100644
index 00000000000..08e9a1ac07a
--- /dev/null
+++ b/include/asm-x86/xsave.h
@@ -0,0 +1,118 @@
+#ifndef __ASM_X86_XSAVE_H
+#define __ASM_X86_XSAVE_H
+
+#include <linux/types.h>
+#include <asm/processor.h>
+#include <asm/i387.h>
+
+#define XSTATE_FP 0x1
+#define XSTATE_SSE 0x2
+
+#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE)
+
+#define FXSAVE_SIZE 512
+
+/*
+ * These are the features that the OS can handle currently.
+ */
+#define XCNTXT_MASK (XSTATE_FP | XSTATE_SSE)
+
+#ifdef CONFIG_X86_64
+#define REX_PREFIX "0x48, "
+#else
+#define REX_PREFIX
+#endif
+
+extern unsigned int xstate_size;
+extern u64 pcntxt_mask;
+extern struct xsave_struct *init_xstate_buf;
+
+extern void xsave_cntxt_init(void);
+extern void xsave_init(void);
+extern int init_fpu(struct task_struct *child);
+extern int check_for_xstate(struct i387_fxsave_struct __user *buf,
+ void __user *fpstate,
+ struct _fpx_sw_bytes *sw);
+
+static inline int xrstor_checking(struct xsave_struct *fx)
+{
+ int err;
+
+ asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
+ "2:\n"
+ ".section .fixup,\"ax\"\n"
+ "3: movl $-1,%[err]\n"
+ " jmp 2b\n"
+ ".previous\n"
+ _ASM_EXTABLE(1b, 3b)
+ : [err] "=r" (err)
+ : "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
+ : "memory");
+
+ return err;
+}
+
+static inline int xsave_user(struct xsave_struct __user *buf)
+{
+ int err;
+ __asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
+ "2:\n"
+ ".section .fixup,\"ax\"\n"
+ "3: movl $-1,%[err]\n"
+ " jmp 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ _ASM_ALIGN "\n"
+ _ASM_PTR "1b,3b\n"
+ ".previous"
+ : [err] "=r" (err)
+ : "D" (buf), "a" (-1), "d" (-1), "0" (0)
+ : "memory");
+ if (unlikely(err) && __clear_user(buf, xstate_size))
+ err = -EFAULT;
+ /* No need to clear here because the caller clears USED_MATH */
+ return err;
+}
+
+static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
+{
+ int err;
+ 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"
+ "2:\n"
+ ".section .fixup,\"ax\"\n"
+ "3: movl $-1,%[err]\n"
+ " jmp 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ _ASM_ALIGN "\n"
+ _ASM_PTR "1b,3b\n"
+ ".previous"
+ : [err] "=r" (err)
+ : "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
+ : "memory"); /* memory required? */
+ return err;
+}
+
+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"
+ : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
+ : "memory");
+}
+
+static inline void xsave(struct task_struct *tsk)
+{
+ /* This, however, we can work around by forcing the compiler to select
+ an addressing mode that doesn't require extended registers. */
+ __asm__ __volatile__(".byte " REX_PREFIX "0x0f,0xae,0x27"
+ : : "D" (&(tsk->thread.xstate->xsave)),
+ "a" (-1), "d"(-1) : "memory");
+}
+#endif
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-25 01:21:13 +0000