The following commit has been merged into the x86/fpu branch of tip:
Commit-ID: adc997b3d66d1cfa8c15a7dbafdaef239a51b5db
Gitweb: https://git.kernel.org/tip/adc997b3d66d1cfa8c15a7dbafdaef239a51b5db
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Wed, 23 Jun 2021 14:01:43 +02:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Wed, 23 Jun 2021 17:49:47 +02:00
x86/fpu: Use copy_xstate_to_uabi_buf() in xfpregs_get()
Use the new functionality of copy_xstate_to_uabi_buf() to retrieve the
FX state when XSAVE* is in use. This avoids overwriting the FPU state
buffer with fpstate_sanitize_xstate() which is error prone and duplicated
code.
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/20210623121452.901736860@xxxxxxxxxxxxx
---
arch/x86/kernel/fpu/regset.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c
index 783f84d..ccbe25f 100644
--- a/arch/x86/kernel/fpu/regset.c
+++ b/arch/x86/kernel/fpu/regset.c
@@ -33,13 +33,18 @@ int xfpregs_get(struct task_struct *target, const struct user_regset *regset,
{
struct fpu *fpu = &target->thread.fpu;
- if (!boot_cpu_has(X86_FEATURE_FXSR))
+ if (!cpu_feature_enabled(X86_FEATURE_FXSR))
return -ENODEV;
fpu__prepare_read(fpu);
- fpstate_sanitize_xstate(fpu);
- return membuf_write(&to, &fpu->state.fxsave, sizeof(struct fxregs_state));
+ if (!use_xsave()) {
+ return membuf_write(&to, &fpu->state.fxsave,
+ sizeof(fpu->state.fxsave));
+ }
+
+ copy_xstate_to_uabi_buf(to, &fpu->state.xsave, XSTATE_COPY_FX);
+ return 0;
}
int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
|