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-rw-r--r--arch/powerpc/kernel/process.c109
1 files changed, 64 insertions, 45 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index ce393df243aa..f0fbbf6a6a1f 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Derived from "arch/i386/kernel/process.c"
* Copyright (C) 1995 Linus Torvalds
@@ -7,11 +8,6 @@
*
* PowerPC version
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
*/
#include <linux/errno.h>
@@ -67,6 +63,7 @@
#include <asm/cpu_has_feature.h>
#include <asm/asm-prototypes.h>
#include <asm/stacktrace.h>
+#include <asm/hw_breakpoint.h>
#include <linux/kprobes.h>
#include <linux/kdebug.h>
@@ -133,7 +130,8 @@ static int __init enable_strict_msr_control(char *str)
}
early_param("ppc_strict_facility_enable", enable_strict_msr_control);
-unsigned long msr_check_and_set(unsigned long bits)
+/* notrace because it's called by restore_math */
+unsigned long notrace msr_check_and_set(unsigned long bits)
{
unsigned long oldmsr = mfmsr();
unsigned long newmsr;
@@ -152,7 +150,8 @@ unsigned long msr_check_and_set(unsigned long bits)
}
EXPORT_SYMBOL_GPL(msr_check_and_set);
-void __msr_check_and_clear(unsigned long bits)
+/* notrace because it's called by restore_math */
+void notrace __msr_check_and_clear(unsigned long bits)
{
unsigned long oldmsr = mfmsr();
unsigned long newmsr;
@@ -176,7 +175,7 @@ static void __giveup_fpu(struct task_struct *tsk)
save_fpu(tsk);
msr = tsk->thread.regs->msr;
- msr &= ~MSR_FP;
+ msr &= ~(MSR_FP|MSR_FE0|MSR_FE1);
#ifdef CONFIG_VSX
if (cpu_has_feature(CPU_FTR_VSX))
msr &= ~MSR_VSX;
@@ -525,7 +524,17 @@ void giveup_all(struct task_struct *tsk)
}
EXPORT_SYMBOL(giveup_all);
-void restore_math(struct pt_regs *regs)
+/*
+ * The exception exit path calls restore_math() with interrupts hard disabled
+ * but the soft irq state not "reconciled". ftrace code that calls
+ * local_irq_save/restore causes warnings.
+ *
+ * Rather than complicate the exit path, just don't trace restore_math. This
+ * could be done by having ftrace entry code check for this un-reconciled
+ * condition where MSR[EE]=0 and PACA_IRQ_HARD_DIS is not set, and
+ * temporarily fix it up for the duration of the ftrace call.
+ */
+void notrace restore_math(struct pt_regs *regs)
{
unsigned long msr;
@@ -784,7 +793,7 @@ static inline int set_dabr(struct arch_hw_breakpoint *brk)
return __set_dabr(dabr, dabrx);
}
-static inline int set_dawr(struct arch_hw_breakpoint *brk)
+int set_dawr(struct arch_hw_breakpoint *brk)
{
unsigned long dawr, dawrx, mrd;
@@ -816,7 +825,7 @@ void __set_breakpoint(struct arch_hw_breakpoint *brk)
{
memcpy(this_cpu_ptr(&current_brk), brk, sizeof(*brk));
- if (cpu_has_feature(CPU_FTR_DAWR))
+ if (dawr_enabled())
// Power8 or later
set_dawr(brk);
else if (!cpu_has_feature(CPU_FTR_ARCH_207S))
@@ -830,8 +839,8 @@ void __set_breakpoint(struct arch_hw_breakpoint *brk)
/* Check if we have DAWR or DABR hardware */
bool ppc_breakpoint_available(void)
{
- if (cpu_has_feature(CPU_FTR_DAWR))
- return true; /* POWER8 DAWR */
+ if (dawr_enabled())
+ return true; /* POWER8 DAWR or POWER9 forced DAWR */
if (cpu_has_feature(CPU_FTR_ARCH_207S))
return false; /* POWER9 with DAWR disabled */
/* DABR: Everything but POWER8 and POWER9 */
@@ -1151,11 +1160,6 @@ static inline void restore_sprs(struct thread_struct *old_thread,
thread_pkey_regs_restore(new_thread, old_thread);
}
-#ifdef CONFIG_PPC_BOOK3S_64
-#define CP_SIZE 128
-static const u8 dummy_copy_buffer[CP_SIZE] __attribute__((aligned(CP_SIZE)));
-#endif
-
struct task_struct *__switch_to(struct task_struct *prev,
struct task_struct *new)
{
@@ -1231,8 +1235,8 @@ struct task_struct *__switch_to(struct task_struct *prev,
batch->active = 1;
}
- if (current_thread_info()->task->thread.regs) {
- restore_math(current_thread_info()->task->thread.regs);
+ if (current->thread.regs) {
+ restore_math(current->thread.regs);
/*
* The copy-paste buffer can only store into foreign real
@@ -1242,7 +1246,7 @@ struct task_struct *__switch_to(struct task_struct *prev,
* mappings, we must issue a cp_abort to clear any state and
* prevent snooping, corruption or a covert channel.
*/
- if (current_thread_info()->task->thread.used_vas)
+ if (current->thread.used_vas)
asm volatile(PPC_CP_ABORT);
}
#endif /* CONFIG_PPC_BOOK3S_64 */
@@ -1634,7 +1638,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
struct thread_info *ti = task_thread_info(p);
- klp_init_thread_info(ti);
+ klp_init_thread_info(p);
/* Copy registers */
sp -= sizeof(struct pt_regs);
@@ -1691,8 +1695,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
sp -= STACK_FRAME_OVERHEAD;
p->thread.ksp = sp;
#ifdef CONFIG_PPC32
- p->thread.ksp_limit = (unsigned long)task_stack_page(p) +
- _ALIGN_UP(sizeof(struct thread_info), 16);
+ p->thread.ksp_limit = (unsigned long)end_of_stack(p);
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
p->thread.ptrace_bps[0] = NULL;
@@ -1730,7 +1733,8 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */
#ifdef CONFIG_PPC_BOOK3S_64
- preload_new_slb_context(start, sp);
+ if (!radix_enabled())
+ preload_new_slb_context(start, sp);
#endif
#endif
@@ -1995,21 +1999,14 @@ static inline int valid_irq_stack(unsigned long sp, struct task_struct *p,
unsigned long stack_page;
unsigned long cpu = task_cpu(p);
- /*
- * Avoid crashing if the stack has overflowed and corrupted
- * task_cpu(p), which is in the thread_info struct.
- */
- if (cpu < NR_CPUS && cpu_possible(cpu)) {
- stack_page = (unsigned long) hardirq_ctx[cpu];
- if (sp >= stack_page + sizeof(struct thread_struct)
- && sp <= stack_page + THREAD_SIZE - nbytes)
- return 1;
-
- stack_page = (unsigned long) softirq_ctx[cpu];
- if (sp >= stack_page + sizeof(struct thread_struct)
- && sp <= stack_page + THREAD_SIZE - nbytes)
- return 1;
- }
+ stack_page = (unsigned long)hardirq_ctx[cpu];
+ if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes)
+ return 1;
+
+ stack_page = (unsigned long)softirq_ctx[cpu];
+ if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes)
+ return 1;
+
return 0;
}
@@ -2018,8 +2015,10 @@ int validate_sp(unsigned long sp, struct task_struct *p,
{
unsigned long stack_page = (unsigned long)task_stack_page(p);
- if (sp >= stack_page + sizeof(struct thread_struct)
- && sp <= stack_page + THREAD_SIZE - nbytes)
+ if (sp < THREAD_SIZE)
+ return 0;
+
+ if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes)
return 1;
return valid_irq_stack(sp, p, nbytes);
@@ -2027,7 +2026,7 @@ int validate_sp(unsigned long sp, struct task_struct *p,
EXPORT_SYMBOL(validate_sp);
-unsigned long get_wchan(struct task_struct *p)
+static unsigned long __get_wchan(struct task_struct *p)
{
unsigned long ip, sp;
int count = 0;
@@ -2053,6 +2052,20 @@ unsigned long get_wchan(struct task_struct *p)
return 0;
}
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long ret;
+
+ if (!try_get_task_stack(p))
+ return 0;
+
+ ret = __get_wchan(p);
+
+ put_task_stack(p);
+
+ return ret;
+}
+
static int kstack_depth_to_print = CONFIG_PRINT_STACK_DEPTH;
void show_stack(struct task_struct *tsk, unsigned long *stack)
@@ -2067,9 +2080,13 @@ void show_stack(struct task_struct *tsk, unsigned long *stack)
int curr_frame = 0;
#endif
- sp = (unsigned long) stack;
if (tsk == NULL)
tsk = current;
+
+ if (!try_get_task_stack(tsk))
+ return;
+
+ sp = (unsigned long) stack;
if (sp == 0) {
if (tsk == current)
sp = current_stack_pointer();
@@ -2081,7 +2098,7 @@ void show_stack(struct task_struct *tsk, unsigned long *stack)
printk("Call Trace:\n");
do {
if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD))
- return;
+ break;
stack = (unsigned long *) sp;
newsp = stack[0];
@@ -2121,6 +2138,8 @@ void show_stack(struct task_struct *tsk, unsigned long *stack)
sp = newsp;
} while (count++ < kstack_depth_to_print);
+
+ put_task_stack(tsk);
}
#ifdef CONFIG_PPC64
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-09 06:35:08 +0000