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Date: Thu, 1 Oct 2020 13:38:53 -0700
From: "Chang S. Bae" <chang.seok.bae@...el.com>
To: tglx@...utronix.de, mingo@...nel.org, bp@...e.de, luto@...nel.org,
x86@...nel.org
Cc: len.brown@...el.com, dave.hansen@...el.com, jing2.liu@...el.com,
ravi.v.shankar@...el.com, linux-kernel@...r.kernel.org,
chang.seok.bae@...el.com
Subject: [RFC PATCH 02/22] x86/fpu/xstate: Modify xstate copy helper prototypes to access all the possible areas
The xstate infrastructure is not flexible to support dynamic areas in
task->fpu. Make the xstate copy functions to access task->fpu directly.
No functional change.
Signed-off-by: Chang S. Bae <chang.seok.bae@...el.com>
Reviewed-by: Len Brown <len.brown@...el.com>
Cc: x86@...nel.org
Cc: linux-kernel@...r.kernel.org
---
arch/x86/include/asm/fpu/xstate.h | 8 ++++----
arch/x86/kernel/fpu/regset.c | 6 +++---
arch/x86/kernel/fpu/signal.c | 17 ++++++++---------
arch/x86/kernel/fpu/xstate.c | 19 +++++++++++++++----
4 files changed, 30 insertions(+), 20 deletions(-)
diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h
index 14ab815132d4..a315b055212f 100644
--- a/arch/x86/include/asm/fpu/xstate.h
+++ b/arch/x86/include/asm/fpu/xstate.h
@@ -105,10 +105,10 @@ const void *get_xsave_field_ptr(int xfeature_nr);
int using_compacted_format(void);
int xfeature_size(int xfeature_nr);
struct membuf;
-void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave);
-int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
-int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
-void copy_supervisor_to_kernel(struct xregs_state *xsave);
+void copy_xstate_to_kernel(struct membuf to, struct fpu *fpu);
+int copy_kernel_to_xstate(struct fpu *fpu, const void *kbuf);
+int copy_user_to_xstate(struct fpu *fpu, const void __user *ubuf);
+void copy_supervisor_to_kernel(struct fpu *fpu);
void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask);
void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask);
diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c
index 4c4d9059ff36..5e13e58d11d4 100644
--- a/arch/x86/kernel/fpu/regset.c
+++ b/arch/x86/kernel/fpu/regset.c
@@ -85,7 +85,7 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset,
fpu__prepare_read(fpu);
if (using_compacted_format()) {
- copy_xstate_to_kernel(to, xsave);
+ copy_xstate_to_kernel(to, fpu);
return 0;
} else {
fpstate_sanitize_xstate(fpu);
@@ -126,9 +126,9 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset,
if (using_compacted_format()) {
if (kbuf)
- ret = copy_kernel_to_xstate(xsave, kbuf);
+ ret = copy_kernel_to_xstate(fpu, kbuf);
else
- ret = copy_user_to_xstate(xsave, ubuf);
+ ret = copy_user_to_xstate(fpu, ubuf);
} else {
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, xsave, 0, -1);
if (!ret)
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index 9f009525f551..adbf63114bc2 100644
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -212,11 +212,11 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size)
}
static inline void
-sanitize_restored_user_xstate(union fpregs_state *state,
+sanitize_restored_user_xstate(struct fpu *fpu,
struct user_i387_ia32_struct *ia32_env,
u64 user_xfeatures, int fx_only)
{
- struct xregs_state *xsave = &state->xsave;
+ struct xregs_state *xsave = &fpu->state.xsave;
struct xstate_header *header = &xsave->header;
if (use_xsave()) {
@@ -253,7 +253,7 @@ sanitize_restored_user_xstate(union fpregs_state *state,
xsave->i387.mxcsr &= mxcsr_feature_mask;
if (ia32_env)
- convert_to_fxsr(&state->fxsave, ia32_env);
+ convert_to_fxsr(&fpu->state.fxsave, ia32_env);
}
}
@@ -396,7 +396,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
* current supervisor states first and invalidate the FPU regs.
*/
if (xfeatures_mask_supervisor())
- copy_supervisor_to_kernel(&fpu->state.xsave);
+ copy_supervisor_to_kernel(fpu);
set_thread_flag(TIF_NEED_FPU_LOAD);
}
__fpu_invalidate_fpregs_state(fpu);
@@ -406,18 +406,18 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
u64 init_bv = xfeatures_mask_user() & ~user_xfeatures;
if (using_compacted_format()) {
- ret = copy_user_to_xstate(&fpu->state.xsave, buf_fx);
+ ret = copy_user_to_xstate(fpu, buf_fx);
} else {
ret = __copy_from_user(&fpu->state.xsave, buf_fx, state_size);
if (!ret && state_size > offsetof(struct xregs_state, header))
ret = validate_user_xstate_header(&fpu->state.xsave.header);
+
}
if (ret)
goto err_out;
- sanitize_restored_user_xstate(&fpu->state, envp, user_xfeatures,
- fx_only);
+ sanitize_restored_user_xstate(fpu, envp, user_xfeatures, fx_only);
fpregs_lock();
if (unlikely(init_bv))
@@ -437,8 +437,7 @@ static int __fpu__restore_sig(void __user *buf, void __user *buf_fx, int size)
goto err_out;
}
- sanitize_restored_user_xstate(&fpu->state, envp, user_xfeatures,
- fx_only);
+ sanitize_restored_user_xstate(fpu, envp, user_xfeatures, fx_only);
fpregs_lock();
if (use_xsave()) {
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index ee4946c60ab1..e3a9bddc39d9 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1067,14 +1067,17 @@ static void copy_part(struct membuf *to, unsigned *last, unsigned offset,
* It supports partial copy but pos always starts from zero. This is called
* from xstateregs_get() and there we check the CPU has XSAVES.
*/
-void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave)
+void copy_xstate_to_kernel(struct membuf to, struct fpu *fpu)
{
struct xstate_header header;
const unsigned off_mxcsr = offsetof(struct fxregs_state, mxcsr);
+ struct xregs_state *xsave;
unsigned size = to.left;
unsigned last = 0;
int i;
+ xsave = &fpu->state.xsave;
+
/*
* The destination is a ptrace buffer; we put in only user xstates:
*/
@@ -1123,8 +1126,9 @@ void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave)
* Convert from a ptrace standard-format kernel buffer to kernel XSAVES format
* and copy to the target thread. This is called from xstateregs_set().
*/
-int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
+int copy_kernel_to_xstate(struct fpu *fpu, const void *kbuf)
{
+ struct xregs_state *xsave;
unsigned int offset, size;
int i;
struct xstate_header hdr;
@@ -1137,6 +1141,8 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
if (validate_user_xstate_header(&hdr))
return -EINVAL;
+ xsave = &fpu->state.xsave;
+
for (i = 0; i < XFEATURE_MAX; i++) {
u64 mask = ((u64)1 << i);
@@ -1176,8 +1182,9 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
* xstateregs_set(), as well as potentially from the sigreturn() and
* rt_sigreturn() system calls.
*/
-int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf)
+int copy_user_to_xstate(struct fpu *fpu, const void __user *ubuf)
{
+ struct xregs_state *xsave;
unsigned int offset, size;
int i;
struct xstate_header hdr;
@@ -1191,6 +1198,8 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf)
if (validate_user_xstate_header(&hdr))
return -EINVAL;
+ xsave = &fpu->state.xsave;
+
for (i = 0; i < XFEATURE_MAX; i++) {
u64 mask = ((u64)1 << i);
@@ -1231,9 +1240,10 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf)
* old states, and is intended to be used only in __fpu__restore_sig(), where
* user states are restored from the user buffer.
*/
-void copy_supervisor_to_kernel(struct xregs_state *xstate)
+void copy_supervisor_to_kernel(struct fpu *fpu)
{
struct xstate_header *header;
+ struct xregs_state *xstate;
u64 max_bit, min_bit;
u32 lmask, hmask;
int err, i;
@@ -1247,6 +1257,7 @@ void copy_supervisor_to_kernel(struct xregs_state *xstate)
max_bit = __fls(xfeatures_mask_supervisor());
min_bit = __ffs(xfeatures_mask_supervisor());
+ xstate = &fpu->state.xsave;
lmask = xfeatures_mask_supervisor();
hmask = xfeatures_mask_supervisor() >> 32;
XSTATE_OP(XSAVES, xstate, lmask, hmask, err);
--
2.17.1
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