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authorJulien Thierry <julien.thierry@arm.com>2019-01-09 12:26:52 -0500
committerDavid A. Long <dave.long@linaro.org>2019-02-13 12:14:33 -0500
commit984a3991d07e53553804c91c1980c45e305d733b (patch)
treea6f9aceb46a84f734efedd86b2f3d6cd48d15e95
parent4ff255f8967c2a1a2fa5261c98a1ef6f065acf2b (diff)
downloadlinux-linaro-stable-984a3991d07e53553804c91c1980c45e305d733b.tar.gz
ARM: 8791/1: vfp: use __copy_to_user() when saving VFP state
Commit 3aa2df6ec2ca6bc143a65351cca4266d03a8bc41 upstream. Use __copy_to_user() rather than __put_user_error() for individual members when saving VFP state. This has the benefit of disabling/enabling PAN once per copied struct intead of once per write. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David A. Long <dave.long@linaro.org>
-rw-r--r--arch/arm/include/asm/thread_info.h4
-rw-r--r--arch/arm/kernel/signal.c13
-rw-r--r--arch/arm/vfp/vfpmodule.c20
3 files changed, 17 insertions, 20 deletions
diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index 9b37b6ab27fe..8f55dc520a3e 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -121,8 +121,8 @@ extern void vfp_flush_hwstate(struct thread_info *);
struct user_vfp;
struct user_vfp_exc;
-extern int vfp_preserve_user_clear_hwstate(struct user_vfp __user *,
- struct user_vfp_exc __user *);
+extern int vfp_preserve_user_clear_hwstate(struct user_vfp *,
+ struct user_vfp_exc *);
extern int vfp_restore_user_hwstate(struct user_vfp *,
struct user_vfp_exc *);
#endif
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c
index 464393d241e1..1e2ecfe080bb 100644
--- a/arch/arm/kernel/signal.c
+++ b/arch/arm/kernel/signal.c
@@ -137,17 +137,18 @@ static int restore_iwmmxt_context(char __user **auxp)
static int preserve_vfp_context(struct vfp_sigframe __user *frame)
{
- const unsigned long magic = VFP_MAGIC;
- const unsigned long size = VFP_STORAGE_SIZE;
+ struct vfp_sigframe kframe;
int err = 0;
- __put_user_error(magic, &frame->magic, err);
- __put_user_error(size, &frame->size, err);
+ memset(&kframe, 0, sizeof(kframe));
+ kframe.magic = VFP_MAGIC;
+ kframe.size = VFP_STORAGE_SIZE;
+ err = vfp_preserve_user_clear_hwstate(&kframe.ufp, &kframe.ufp_exc);
if (err)
- return -EFAULT;
+ return err;
- return vfp_preserve_user_clear_hwstate(&frame->ufp, &frame->ufp_exc);
+ return __copy_to_user(frame, &kframe, sizeof(kframe));
}
static int restore_vfp_context(char __user **auxp)
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index dc7e6b50ef67..2b287d0d6bc2 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -553,12 +553,11 @@ void vfp_flush_hwstate(struct thread_info *thread)
* Save the current VFP state into the provided structures and prepare
* for entry into a new function (signal handler).
*/
-int vfp_preserve_user_clear_hwstate(struct user_vfp __user *ufp,
- struct user_vfp_exc __user *ufp_exc)
+int vfp_preserve_user_clear_hwstate(struct user_vfp *ufp,
+ struct user_vfp_exc *ufp_exc)
{
struct thread_info *thread = current_thread_info();
struct vfp_hard_struct *hwstate = &thread->vfpstate.hard;
- int err = 0;
/* Ensure that the saved hwstate is up-to-date. */
vfp_sync_hwstate(thread);
@@ -567,22 +566,19 @@ int vfp_preserve_user_clear_hwstate(struct user_vfp __user *ufp,
* Copy the floating point registers. There can be unused
* registers see asm/hwcap.h for details.
*/
- err |= __copy_to_user(&ufp->fpregs, &hwstate->fpregs,
- sizeof(hwstate->fpregs));
+ memcpy(&ufp->fpregs, &hwstate->fpregs, sizeof(hwstate->fpregs));
+
/*
* Copy the status and control register.
*/
- __put_user_error(hwstate->fpscr, &ufp->fpscr, err);
+ ufp->fpscr = hwstate->fpscr;
/*
* Copy the exception registers.
*/
- __put_user_error(hwstate->fpexc, &ufp_exc->fpexc, err);
- __put_user_error(hwstate->fpinst, &ufp_exc->fpinst, err);
- __put_user_error(hwstate->fpinst2, &ufp_exc->fpinst2, err);
-
- if (err)
- return -EFAULT;
+ ufp_exc->fpexc = hwstate->fpexc;
+ ufp_exc->fpinst = hwstate->fpinst;
+ ufp_exc->fpinst2 = ufp_exc->fpinst2;
/* Ensure that VFP is disabled. */
vfp_flush_hwstate(thread);