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Diffstat (limited to 'arch/x86/kernel/i387.c')
-rw-r--r--arch/x86/kernel/i387.c71
1 files changed, 67 insertions, 4 deletions
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index f2f8540a7f3d..c01a2b846d47 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -164,6 +164,11 @@ int init_fpu(struct task_struct *tsk)
return 0;
}
+/*
+ * The xstateregs_active() routine is the same as the fpregs_active() routine,
+ * as the "regset->n" for the xstate regset will be updated based on the feature
+ * capabilites supported by the xsave.
+ */
int fpregs_active(struct task_struct *target, const struct user_regset *regset)
{
return tsk_used_math(target) ? regset->n : 0;
@@ -204,8 +209,6 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
if (ret)
return ret;
- set_stopped_child_used_math(target);
-
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.xstate->fxsave, 0, -1);
@@ -224,6 +227,68 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
return ret;
}
+int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ int ret;
+
+ if (!cpu_has_xsave)
+ return -ENODEV;
+
+ ret = init_fpu(target);
+ if (ret)
+ return ret;
+
+ /*
+ * Copy the 48bytes defined by the software first into the xstate
+ * memory layout in the thread struct, so that we can copy the entire
+ * xstateregs to the user using one user_regset_copyout().
+ */
+ memcpy(&target->thread.xstate->fxsave.sw_reserved,
+ xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes));
+
+ /*
+ * Copy the xstate memory layout.
+ */
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ &target->thread.xstate->xsave, 0, -1);
+ return ret;
+}
+
+int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct xsave_hdr_struct *xsave_hdr;
+
+ if (!cpu_has_xsave)
+ return -ENODEV;
+
+ ret = init_fpu(target);
+ if (ret)
+ return ret;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.xstate->xsave, 0, -1);
+
+ /*
+ * mxcsr reserved bits must be masked to zero for security reasons.
+ */
+ target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask;
+
+ xsave_hdr = &target->thread.xstate->xsave.xsave_hdr;
+
+ xsave_hdr->xstate_bv &= pcntxt_mask;
+ /*
+ * These bits must be zero.
+ */
+ xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0;
+
+ return ret;
+}
+
#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
/*
@@ -404,8 +469,6 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset,
if (ret)
return ret;
- set_stopped_child_used_math(target);
-
if (!HAVE_HWFP)
return fpregs_soft_set(target, regset, pos, count, kbuf, ubuf);