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-rw-r--r--arch/powerpc/kernel/process.c107
1 files changed, 70 insertions, 37 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 8935c5696bce..185beb290580 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -96,7 +96,8 @@ static void check_if_tm_restore_required(struct task_struct *tsk)
if (tsk == current && tsk->thread.regs &&
MSR_TM_ACTIVE(tsk->thread.regs->msr) &&
!test_thread_flag(TIF_RESTORE_TM)) {
- tsk->thread.ckpt_regs.msr = tsk->thread.regs->msr;
+ regs_set_return_msr(&tsk->thread.ckpt_regs,
+ tsk->thread.regs->msr);
set_thread_flag(TIF_RESTORE_TM);
}
}
@@ -161,7 +162,7 @@ static void __giveup_fpu(struct task_struct *tsk)
msr &= ~(MSR_FP|MSR_FE0|MSR_FE1);
if (cpu_has_feature(CPU_FTR_VSX))
msr &= ~MSR_VSX;
- tsk->thread.regs->msr = msr;
+ regs_set_return_msr(tsk->thread.regs, msr);
}
void giveup_fpu(struct task_struct *tsk)
@@ -244,7 +245,7 @@ static void __giveup_altivec(struct task_struct *tsk)
msr &= ~MSR_VEC;
if (cpu_has_feature(CPU_FTR_VSX))
msr &= ~MSR_VSX;
- tsk->thread.regs->msr = msr;
+ regs_set_return_msr(tsk->thread.regs, msr);
}
void giveup_altivec(struct task_struct *tsk)
@@ -559,7 +560,7 @@ void notrace restore_math(struct pt_regs *regs)
msr_check_and_clear(new_msr);
- regs->msr |= new_msr | fpexc_mode;
+ regs_set_return_msr(regs, regs->msr | new_msr | fpexc_mode);
}
}
#endif /* CONFIG_PPC_BOOK3S_64 */
@@ -1114,7 +1115,7 @@ void restore_tm_state(struct pt_regs *regs)
#endif
restore_math(regs);
- regs->msr |= msr_diff;
+ regs_set_return_msr(regs, regs->msr | msr_diff);
}
#else /* !CONFIG_PPC_TRANSACTIONAL_MEM */
@@ -1129,6 +1130,10 @@ static inline void save_sprs(struct thread_struct *t)
if (cpu_has_feature(CPU_FTR_ALTIVEC))
t->vrsave = mfspr(SPRN_VRSAVE);
#endif
+#ifdef CONFIG_SPE
+ if (cpu_has_feature(CPU_FTR_SPE))
+ t->spefscr = mfspr(SPRN_SPEFSCR);
+#endif
#ifdef CONFIG_PPC_BOOK3S_64
if (cpu_has_feature(CPU_FTR_DSCR))
t->dscr = mfspr(SPRN_DSCR);
@@ -1159,6 +1164,11 @@ static inline void restore_sprs(struct thread_struct *old_thread,
old_thread->vrsave != new_thread->vrsave)
mtspr(SPRN_VRSAVE, new_thread->vrsave);
#endif
+#ifdef CONFIG_SPE
+ if (cpu_has_feature(CPU_FTR_SPE) &&
+ old_thread->spefscr != new_thread->spefscr)
+ mtspr(SPRN_SPEFSCR, new_thread->spefscr);
+#endif
#ifdef CONFIG_PPC_BOOK3S_64
if (cpu_has_feature(CPU_FTR_DSCR)) {
u64 dscr = get_paca()->dscr_default;
@@ -1213,6 +1223,19 @@ struct task_struct *__switch_to(struct task_struct *prev,
__flush_tlb_pending(batch);
batch->active = 0;
}
+
+ /*
+ * On POWER9 the copy-paste buffer can only paste into
+ * foreign real addresses, so unprivileged processes can not
+ * see the data or use it in any way unless they have
+ * foreign real mappings. If the new process has the foreign
+ * real address mappings, we must issue a cp_abort to clear
+ * any state and prevent snooping, corruption or a covert
+ * channel. ISA v3.1 supports paste into local memory.
+ */
+ if (new->mm && (cpu_has_feature(CPU_FTR_ARCH_31) ||
+ atomic_read(&new->mm->context.vas_windows)))
+ asm volatile(PPC_CP_ABORT);
#endif /* CONFIG_PPC_BOOK3S_64 */
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
@@ -1248,43 +1271,48 @@ struct task_struct *__switch_to(struct task_struct *prev,
}
/*
- * Call restore_sprs() before calling _switch(). If we move it after
- * _switch() then we miss out on calling it for new tasks. The reason
- * for this is we manually create a stack frame for new tasks that
- * directly returns through ret_from_fork() or
+ * Call restore_sprs() and set_return_regs_changed() before calling
+ * _switch(). If we move it after _switch() then we miss out on calling
+ * it for new tasks. The reason for this is we manually create a stack
+ * frame for new tasks that directly returns through ret_from_fork() or
* ret_from_kernel_thread(). See copy_thread() for details.
*/
restore_sprs(old_thread, new_thread);
+ set_return_regs_changed(); /* _switch changes stack (and regs) */
+
#ifdef CONFIG_PPC32
kuap_assert_locked();
#endif
last = _switch(old_thread, new_thread);
+ /*
+ * Nothing after _switch will be run for newly created tasks,
+ * because they switch directly to ret_from_fork/ret_from_kernel_thread
+ * etc. Code added here should have a comment explaining why that is
+ * okay.
+ */
+
#ifdef CONFIG_PPC_BOOK3S_64
+ /*
+ * This applies to a process that was context switched while inside
+ * arch_enter_lazy_mmu_mode(), to re-activate the batch that was
+ * deactivated above, before _switch(). This will never be the case
+ * for new tasks.
+ */
if (current_thread_info()->local_flags & _TLF_LAZY_MMU) {
current_thread_info()->local_flags &= ~_TLF_LAZY_MMU;
batch = this_cpu_ptr(&ppc64_tlb_batch);
batch->active = 1;
}
- if (current->thread.regs) {
+ /*
+ * Math facilities are masked out of the child MSR in copy_thread.
+ * A new task does not need to restore_math because it will
+ * demand fault them.
+ */
+ if (current->thread.regs)
restore_math(current->thread.regs);
-
- /*
- * On POWER9 the copy-paste buffer can only paste into
- * foreign real addresses, so unprivileged processes can not
- * see the data or use it in any way unless they have
- * foreign real mappings. If the new process has the foreign
- * real address mappings, we must issue a cp_abort to clear
- * any state and prevent snooping, corruption or a covert
- * channel. ISA v3.1 supports paste into local memory.
- */
- if (current->mm &&
- (cpu_has_feature(CPU_FTR_ARCH_31) ||
- atomic_read(&current->mm->context.vas_windows)))
- asm volatile(PPC_CP_ABORT);
- }
#endif /* CONFIG_PPC_BOOK3S_64 */
return last;
@@ -1736,6 +1764,9 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
#ifdef CONFIG_ALTIVEC
p->thread.vr_save_area = NULL;
#endif
+#if defined(CONFIG_PPC_BOOK3S_32) && defined(CONFIG_PPC_KUAP)
+ p->thread.kuap = KUAP_NONE;
+#endif
setup_ksp_vsid(p, sp);
@@ -1838,13 +1869,14 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
}
regs->gpr[2] = toc;
}
- regs->nip = entry;
- regs->msr = MSR_USER64;
+ regs_set_return_ip(regs, entry);
+ regs_set_return_msr(regs, MSR_USER64);
} else {
- regs->nip = start;
regs->gpr[2] = 0;
- regs->msr = MSR_USER32;
+ regs_set_return_ip(regs, start);
+ regs_set_return_msr(regs, MSR_USER32);
}
+
#endif
#ifdef CONFIG_VSX
current->thread.used_vsr = 0;
@@ -1875,7 +1907,6 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
current->thread.tm_tfiar = 0;
current->thread.load_tm = 0;
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
-
}
EXPORT_SYMBOL(start_thread);
@@ -1923,9 +1954,10 @@ int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
if (val > PR_FP_EXC_PRECISE)
return -EINVAL;
tsk->thread.fpexc_mode = __pack_fe01(val);
- if (regs != NULL && (regs->msr & MSR_FP) != 0)
- regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1))
- | tsk->thread.fpexc_mode;
+ if (regs != NULL && (regs->msr & MSR_FP) != 0) {
+ regs_set_return_msr(regs, (regs->msr & ~(MSR_FE0|MSR_FE1))
+ | tsk->thread.fpexc_mode);
+ }
return 0;
}
@@ -1971,9 +2003,9 @@ int set_endian(struct task_struct *tsk, unsigned int val)
return -EINVAL;
if (val == PR_ENDIAN_BIG)
- regs->msr &= ~MSR_LE;
+ regs_set_return_msr(regs, regs->msr & ~MSR_LE);
else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE)
- regs->msr |= MSR_LE;
+ regs_set_return_msr(regs, regs->msr | MSR_LE);
else
return -EINVAL;
@@ -2121,8 +2153,9 @@ unsigned long get_wchan(struct task_struct *p)
static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
-void show_stack(struct task_struct *tsk, unsigned long *stack,
- const char *loglvl)
+void __no_sanitize_address show_stack(struct task_struct *tsk,
+ unsigned long *stack,
+ const char *loglvl)
{
unsigned long sp, ip, lr, newsp;
int count = 0;
generated by cgit v1.2.3 (git 2.39.1) at 2025-02-05 18:05:06 +0100