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-rw-r--r--debian/patches-rt/0007-x86-fpu-Remove-fpu-initialized.patch476
1 files changed, 0 insertions, 476 deletions
diff --git a/debian/patches-rt/0007-x86-fpu-Remove-fpu-initialized.patch b/debian/patches-rt/0007-x86-fpu-Remove-fpu-initialized.patch
deleted file mode 100644
index 0073d26ff..000000000
--- a/debian/patches-rt/0007-x86-fpu-Remove-fpu-initialized.patch
+++ /dev/null
@@ -1,476 +0,0 @@
-From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
-Date: Wed, 17 Oct 2018 18:08:35 +0200
-Subject: [PATCH 07/27] x86/fpu: Remove fpu->initialized
-Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.0/older/patches-5.0.10-rt7.tar.xz
-
-The `initialized' member of the fpu struct is always set to one for user
-tasks and zero for kernel tasks. This avoids saving/restoring the FPU
-registers for kernel threads.
-
-The ->initialized = 0 case for user tasks has been removed in previous changes
-for instance by always an explicit init at fork() time for FPU-less system which
-was otherwise delayed until the emulated opcode.
-
-The context switch code (switch_fpu_prepare() + switch_fpu_finish())
-can't unconditionally save/restore registers for kernel threads. Not only would
-it slow down switch but also load a zeroed xcomp_bv for the XSAVES.
-
-For kernel_fpu_begin() (+end) the situation is similar: EFI with runtime
-services uses this before alternatives_patched is true. Which means that this
-function is used too early and it wasn't the case before.
-
-For those two cases current->mm is used to determine between user &
-kernel thread. For kernel_fpu_begin() we skip save/restore of the FPU
-registers.
-During the context switch into a kernel thread we don't do anything.
-There is no reason to save the FPU state of a kernel thread.
-The reordering in __switch_to() is important because the current() pointer
-needs to be valid before switch_fpu_finish() is invoked so ->mm is seen of the
-new task instead the old one.
-
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- arch/x86/ia32/ia32_signal.c | 17 +++-----
- arch/x86/include/asm/fpu/internal.h | 18 +++++----
- arch/x86/include/asm/fpu/types.h | 9 ----
- arch/x86/include/asm/trace/fpu.h | 5 --
- arch/x86/kernel/fpu/core.c | 72 ++++++++++--------------------------
- arch/x86/kernel/fpu/init.c | 2 -
- arch/x86/kernel/fpu/regset.c | 19 ++-------
- arch/x86/kernel/fpu/xstate.c | 2 -
- arch/x86/kernel/process_32.c | 4 +-
- arch/x86/kernel/process_64.c | 4 +-
- arch/x86/kernel/signal.c | 17 +++-----
- arch/x86/mm/pkeys.c | 7 ---
- 12 files changed, 54 insertions(+), 122 deletions(-)
-
---- a/arch/x86/ia32/ia32_signal.c
-+++ b/arch/x86/ia32/ia32_signal.c
-@@ -216,8 +216,7 @@ static void __user *get_sigframe(struct
- size_t frame_size,
- void __user **fpstate)
- {
-- struct fpu *fpu = &current->thread.fpu;
-- unsigned long sp;
-+ unsigned long sp, fx_aligned, math_size;
-
- /* Default to using normal stack */
- sp = regs->sp;
-@@ -231,15 +230,11 @@ static void __user *get_sigframe(struct
- ksig->ka.sa.sa_restorer)
- sp = (unsigned long) ksig->ka.sa.sa_restorer;
-
-- if (fpu->initialized) {
-- unsigned long fx_aligned, math_size;
--
-- sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
-- *fpstate = (struct _fpstate_32 __user *) sp;
-- if (copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
-- math_size) < 0)
-- return (void __user *) -1L;
-- }
-+ sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
-+ *fpstate = (struct _fpstate_32 __user *) sp;
-+ if (copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
-+ math_size) < 0)
-+ return (void __user *) -1L;
-
- sp -= frame_size;
- /* Align the stack pointer according to the i386 ABI,
---- a/arch/x86/include/asm/fpu/internal.h
-+++ b/arch/x86/include/asm/fpu/internal.h
-@@ -525,11 +525,14 @@ static inline void fpregs_activate(struc
- *
- * - switch_fpu_finish() restores the new state as
- * necessary.
-+ *
-+ * The FPU context is only stored/restore for user task and ->mm is used to
-+ * distinguish between kernel and user threads.
- */
- static inline void
- switch_fpu_prepare(struct fpu *old_fpu, int cpu)
- {
-- if (static_cpu_has(X86_FEATURE_FPU) && old_fpu->initialized) {
-+ if (static_cpu_has(X86_FEATURE_FPU) && current->mm) {
- if (!copy_fpregs_to_fpstate(old_fpu))
- old_fpu->last_cpu = -1;
- else
-@@ -537,8 +540,7 @@ switch_fpu_prepare(struct fpu *old_fpu,
-
- /* But leave fpu_fpregs_owner_ctx! */
- trace_x86_fpu_regs_deactivated(old_fpu);
-- } else
-- old_fpu->last_cpu = -1;
-+ }
- }
-
- /*
-@@ -551,12 +553,12 @@ switch_fpu_prepare(struct fpu *old_fpu,
- */
- static inline void switch_fpu_finish(struct fpu *new_fpu, int cpu)
- {
-- bool preload = static_cpu_has(X86_FEATURE_FPU) &&
-- new_fpu->initialized;
-+ if (static_cpu_has(X86_FEATURE_FPU)) {
-+ if (!fpregs_state_valid(new_fpu, cpu)) {
-+ if (current->mm)
-+ copy_kernel_to_fpregs(&new_fpu->state);
-+ }
-
-- if (preload) {
-- if (!fpregs_state_valid(new_fpu, cpu))
-- copy_kernel_to_fpregs(&new_fpu->state);
- fpregs_activate(new_fpu);
- }
- }
---- a/arch/x86/include/asm/fpu/types.h
-+++ b/arch/x86/include/asm/fpu/types.h
-@@ -294,15 +294,6 @@ struct fpu {
- unsigned int last_cpu;
-
- /*
-- * @initialized:
-- *
-- * This flag indicates whether this context is initialized: if the task
-- * is not running then we can restore from this context, if the task
-- * is running then we should save into this context.
-- */
-- unsigned char initialized;
--
-- /*
- * @state:
- *
- * In-memory copy of all FPU registers that we save/restore
---- a/arch/x86/include/asm/trace/fpu.h
-+++ b/arch/x86/include/asm/trace/fpu.h
-@@ -13,22 +13,19 @@ DECLARE_EVENT_CLASS(x86_fpu,
-
- TP_STRUCT__entry(
- __field(struct fpu *, fpu)
-- __field(bool, initialized)
- __field(u64, xfeatures)
- __field(u64, xcomp_bv)
- ),
-
- TP_fast_assign(
- __entry->fpu = fpu;
-- __entry->initialized = fpu->initialized;
- if (boot_cpu_has(X86_FEATURE_OSXSAVE)) {
- __entry->xfeatures = fpu->state.xsave.header.xfeatures;
- __entry->xcomp_bv = fpu->state.xsave.header.xcomp_bv;
- }
- ),
-- TP_printk("x86/fpu: %p initialized: %d xfeatures: %llx xcomp_bv: %llx",
-+ TP_printk("x86/fpu: %p xfeatures: %llx xcomp_bv: %llx",
- __entry->fpu,
-- __entry->initialized,
- __entry->xfeatures,
- __entry->xcomp_bv
- )
---- a/arch/x86/kernel/fpu/core.c
-+++ b/arch/x86/kernel/fpu/core.c
-@@ -101,7 +101,7 @@ static void __kernel_fpu_begin(void)
-
- kernel_fpu_disable();
-
-- if (fpu->initialized) {
-+ if (current->mm) {
- /*
- * Ignore return value -- we don't care if reg state
- * is clobbered.
-@@ -116,7 +116,7 @@ static void __kernel_fpu_end(void)
- {
- struct fpu *fpu = &current->thread.fpu;
-
-- if (fpu->initialized)
-+ if (current->mm)
- copy_kernel_to_fpregs(&fpu->state);
-
- kernel_fpu_enable();
-@@ -147,11 +147,10 @@ void fpu__save(struct fpu *fpu)
-
- preempt_disable();
- trace_x86_fpu_before_save(fpu);
-- if (fpu->initialized) {
-- if (!copy_fpregs_to_fpstate(fpu)) {
-- copy_kernel_to_fpregs(&fpu->state);
-- }
-- }
-+
-+ if (!copy_fpregs_to_fpstate(fpu))
-+ copy_kernel_to_fpregs(&fpu->state);
-+
- trace_x86_fpu_after_save(fpu);
- preempt_enable();
- }
-@@ -190,7 +189,7 @@ int fpu__copy(struct fpu *dst_fpu, struc
- {
- dst_fpu->last_cpu = -1;
-
-- if (!src_fpu->initialized || !static_cpu_has(X86_FEATURE_FPU))
-+ if (!static_cpu_has(X86_FEATURE_FPU))
- return 0;
-
- WARN_ON_FPU(src_fpu != &current->thread.fpu);
-@@ -227,14 +226,10 @@ static void fpu__initialize(struct fpu *
- {
- WARN_ON_FPU(fpu != &current->thread.fpu);
-
-- if (!fpu->initialized) {
-- fpstate_init(&fpu->state);
-- trace_x86_fpu_init_state(fpu);
--
-- trace_x86_fpu_activate_state(fpu);
-- /* Safe to do for the current task: */
-- fpu->initialized = 1;
-- }
-+ fpstate_init(&fpu->state);
-+ trace_x86_fpu_init_state(fpu);
-+
-+ trace_x86_fpu_activate_state(fpu);
- }
-
- /*
-@@ -247,32 +242,20 @@ static void fpu__initialize(struct fpu *
- *
- * - or it's called for stopped tasks (ptrace), in which case the
- * registers were already saved by the context-switch code when
-- * the task scheduled out - we only have to initialize the registers
-- * if they've never been initialized.
-+ * the task scheduled out.
- *
- * If the task has used the FPU before then save it.
- */
- void fpu__prepare_read(struct fpu *fpu)
- {
-- if (fpu == &current->thread.fpu) {
-+ if (fpu == &current->thread.fpu)
- fpu__save(fpu);
-- } else {
-- if (!fpu->initialized) {
-- fpstate_init(&fpu->state);
-- trace_x86_fpu_init_state(fpu);
--
-- trace_x86_fpu_activate_state(fpu);
-- /* Safe to do for current and for stopped child tasks: */
-- fpu->initialized = 1;
-- }
-- }
- }
-
- /*
- * This function must be called before we write a task's fpstate.
- *
-- * If the task has used the FPU before then invalidate any cached FPU registers.
-- * If the task has not used the FPU before then initialize its fpstate.
-+ * Invalidate any cached FPU registers.
- *
- * After this function call, after registers in the fpstate are
- * modified and the child task has woken up, the child task will
-@@ -289,17 +272,8 @@ void fpu__prepare_write(struct fpu *fpu)
- */
- WARN_ON_FPU(fpu == &current->thread.fpu);
-
-- if (fpu->initialized) {
-- /* Invalidate any cached state: */
-- __fpu_invalidate_fpregs_state(fpu);
-- } else {
-- fpstate_init(&fpu->state);
-- trace_x86_fpu_init_state(fpu);
--
-- trace_x86_fpu_activate_state(fpu);
-- /* Safe to do for stopped child tasks: */
-- fpu->initialized = 1;
-- }
-+ /* Invalidate any cached state: */
-+ __fpu_invalidate_fpregs_state(fpu);
- }
-
- /*
-@@ -316,17 +290,13 @@ void fpu__drop(struct fpu *fpu)
- preempt_disable();
-
- if (fpu == &current->thread.fpu) {
-- if (fpu->initialized) {
-- /* Ignore delayed exceptions from user space */
-- asm volatile("1: fwait\n"
-- "2:\n"
-- _ASM_EXTABLE(1b, 2b));
-- fpregs_deactivate(fpu);
-- }
-+ /* Ignore delayed exceptions from user space */
-+ asm volatile("1: fwait\n"
-+ "2:\n"
-+ _ASM_EXTABLE(1b, 2b));
-+ fpregs_deactivate(fpu);
- }
-
-- fpu->initialized = 0;
--
- trace_x86_fpu_dropped(fpu);
-
- preempt_enable();
---- a/arch/x86/kernel/fpu/init.c
-+++ b/arch/x86/kernel/fpu/init.c
-@@ -239,8 +239,6 @@ static void __init fpu__init_system_ctx_
-
- WARN_ON_FPU(!on_boot_cpu);
- on_boot_cpu = 0;
--
-- WARN_ON_FPU(current->thread.fpu.initialized);
- }
-
- /*
---- a/arch/x86/kernel/fpu/regset.c
-+++ b/arch/x86/kernel/fpu/regset.c
-@@ -15,16 +15,12 @@
- */
- int regset_fpregs_active(struct task_struct *target, const struct user_regset *regset)
- {
-- struct fpu *target_fpu = &target->thread.fpu;
--
-- return target_fpu->initialized ? regset->n : 0;
-+ return regset->n;
- }
-
- int regset_xregset_fpregs_active(struct task_struct *target, const struct user_regset *regset)
- {
-- struct fpu *target_fpu = &target->thread.fpu;
--
-- if (boot_cpu_has(X86_FEATURE_FXSR) && target_fpu->initialized)
-+ if (boot_cpu_has(X86_FEATURE_FXSR))
- return regset->n;
- else
- return 0;
-@@ -370,16 +366,9 @@ int fpregs_set(struct task_struct *targe
- int dump_fpu(struct pt_regs *regs, struct user_i387_struct *ufpu)
- {
- struct task_struct *tsk = current;
-- struct fpu *fpu = &tsk->thread.fpu;
-- int fpvalid;
--
-- fpvalid = fpu->initialized;
-- if (fpvalid)
-- fpvalid = !fpregs_get(tsk, NULL,
-- 0, sizeof(struct user_i387_ia32_struct),
-- ufpu, NULL);
-
-- return fpvalid;
-+ return !fpregs_get(tsk, NULL, 0, sizeof(struct user_i387_ia32_struct),
-+ ufpu, NULL);
- }
- EXPORT_SYMBOL(dump_fpu);
-
---- a/arch/x86/kernel/fpu/xstate.c
-+++ b/arch/x86/kernel/fpu/xstate.c
-@@ -892,8 +892,6 @@ const void *get_xsave_field_ptr(int xsav
- {
- struct fpu *fpu = &current->thread.fpu;
-
-- if (!fpu->initialized)
-- return NULL;
- /*
- * fpu__save() takes the CPU's xstate registers
- * and saves them off to the 'fpu memory buffer.
---- a/arch/x86/kernel/process_32.c
-+++ b/arch/x86/kernel/process_32.c
-@@ -288,10 +288,10 @@ EXPORT_SYMBOL_GPL(start_thread);
- if (prev->gs | next->gs)
- lazy_load_gs(next->gs);
-
-- switch_fpu_finish(next_fpu, cpu);
--
- this_cpu_write(current_task, next_p);
-
-+ switch_fpu_finish(next_fpu, cpu);
-+
- /* Load the Intel cache allocation PQR MSR. */
- resctrl_sched_in();
-
---- a/arch/x86/kernel/process_64.c
-+++ b/arch/x86/kernel/process_64.c
-@@ -566,14 +566,14 @@ void compat_start_thread(struct pt_regs
-
- x86_fsgsbase_load(prev, next);
-
-- switch_fpu_finish(next_fpu, cpu);
--
- /*
- * Switch the PDA and FPU contexts.
- */
- this_cpu_write(current_task, next_p);
- this_cpu_write(cpu_current_top_of_stack, task_top_of_stack(next_p));
-
-+ switch_fpu_finish(next_fpu, cpu);
-+
- /* Reload sp0. */
- update_task_stack(next_p);
-
---- a/arch/x86/kernel/signal.c
-+++ b/arch/x86/kernel/signal.c
-@@ -246,7 +246,7 @@ get_sigframe(struct k_sigaction *ka, str
- unsigned long sp = regs->sp;
- unsigned long buf_fx = 0;
- int onsigstack = on_sig_stack(sp);
-- struct fpu *fpu = &current->thread.fpu;
-+ int ret;
-
- /* redzone */
- if (IS_ENABLED(CONFIG_X86_64))
-@@ -265,11 +265,9 @@ get_sigframe(struct k_sigaction *ka, str
- sp = (unsigned long) ka->sa.sa_restorer;
- }
-
-- if (fpu->initialized) {
-- sp = fpu__alloc_mathframe(sp, IS_ENABLED(CONFIG_X86_32),
-- &buf_fx, &math_size);
-- *fpstate = (void __user *)sp;
-- }
-+ sp = fpu__alloc_mathframe(sp, IS_ENABLED(CONFIG_X86_32),
-+ &buf_fx, &math_size);
-+ *fpstate = (void __user *)sp;
-
- sp = align_sigframe(sp - frame_size);
-
-@@ -281,8 +279,8 @@ get_sigframe(struct k_sigaction *ka, str
- return (void __user *)-1L;
-
- /* save i387 and extended state */
-- if (fpu->initialized &&
-- copy_fpstate_to_sigframe(*fpstate, (void __user *)buf_fx, math_size) < 0)
-+ ret = copy_fpstate_to_sigframe(*fpstate, (void __user *)buf_fx, math_size);
-+ if (ret < 0)
- return (void __user *)-1L;
-
- return (void __user *)sp;
-@@ -763,8 +761,7 @@ handle_signal(struct ksignal *ksig, stru
- /*
- * Ensure the signal handler starts with the new fpu state.
- */
-- if (fpu->initialized)
-- fpu__clear(fpu);
-+ fpu__clear(fpu);
- }
- signal_setup_done(failed, ksig, stepping);
- }
---- a/arch/x86/mm/pkeys.c
-+++ b/arch/x86/mm/pkeys.c
-@@ -39,17 +39,12 @@ int __execute_only_pkey(struct mm_struct
- * dance to set PKRU if we do not need to. Check it
- * first and assume that if the execute-only pkey is
- * write-disabled that we do not have to set it
-- * ourselves. We need preempt off so that nobody
-- * can make fpregs inactive.
-+ * ourselves.
- */
-- preempt_disable();
- if (!need_to_set_mm_pkey &&
-- current->thread.fpu.initialized &&
- !__pkru_allows_read(read_pkru(), execute_only_pkey)) {
-- preempt_enable();
- return execute_only_pkey;
- }
-- preempt_enable();
-
- /*
- * Set up PKRU so that it denies access for everything
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-19 04:06:49 +0000