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kernel-49/arch/xtensa/kernel/stacktrace.c
Greg Kroah-Hartman 7515a820d6 Merge 4.9.169 into android-4.9
Changes in 4.9.169
	x86/power: Fix some ordering bugs in __restore_processor_context()
	x86/power/64: Use struct desc_ptr for the IDT in struct saved_context
	x86/power/32: Move SYSENTER MSR restoration to fix_processor_context()
	x86/power: Make restore_processor_context() sane
	powerpc/tm: Limit TM code inside PPC_TRANSACTIONAL_MEM
	kbuild: clang: choose GCC_TOOLCHAIN_DIR not on LD
	x86: vdso: Use $LD instead of $CC to link
	x86/vdso: Drop implicit common-page-size linker flag
	lib/string.c: implement a basic bcmp
	powerpc: Fix invalid use of register expressions
	powerpc/64s: Add barrier_nospec
	powerpc/64s: Add support for ori barrier_nospec patching
	powerpc: Avoid code patching freed init sections
	powerpc/64s: Patch barrier_nospec in modules
	powerpc/64s: Enable barrier_nospec based on firmware settings
	powerpc: Use barrier_nospec in copy_from_user()
	powerpc/64: Use barrier_nospec in syscall entry
	powerpc/64s: Enhance the information in cpu_show_spectre_v1()
	powerpc64s: Show ori31 availability in spectre_v1 sysfs file not v2
	powerpc/64: Disable the speculation barrier from the command line
	powerpc/64: Make stf barrier PPC_BOOK3S_64 specific.
	powerpc/64: Add CONFIG_PPC_BARRIER_NOSPEC
	powerpc/64: Call setup_barrier_nospec() from setup_arch()
	powerpc/64: Make meltdown reporting Book3S 64 specific
	powerpc/fsl: Add barrier_nospec implementation for NXP PowerPC Book3E
	powerpc/fsl: Sanitize the syscall table for NXP PowerPC 32 bit platforms
	powerpc/asm: Add a patch_site macro & helpers for patching instructions
	powerpc/64s: Add new security feature flags for count cache flush
	powerpc/64s: Add support for software count cache flush
	powerpc/pseries: Query hypervisor for count cache flush settings
	powerpc/powernv: Query firmware for count cache flush settings
	powerpc/fsl: Add infrastructure to fixup branch predictor flush
	powerpc/fsl: Add macro to flush the branch predictor
	powerpc/fsl: Fix spectre_v2 mitigations reporting
	powerpc/fsl: Emulate SPRN_BUCSR register
	powerpc/fsl: Add nospectre_v2 command line argument
	powerpc/fsl: Flush the branch predictor at each kernel entry (64bit)
	powerpc/fsl: Flush the branch predictor at each kernel entry (32 bit)
	powerpc/fsl: Flush branch predictor when entering KVM
	powerpc/fsl: Enable runtime patching if nospectre_v2 boot arg is used
	powerpc/fsl: Update Spectre v2 reporting
	powerpc/fsl: Fixed warning: orphan section `__btb_flush_fixup'
	powerpc/fsl: Fix the flush of branch predictor.
	powerpc/security: Fix spectre_v2 reporting
	arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region
	tty: mark Siemens R3964 line discipline as BROKEN
	tty: ldisc: add sysctl to prevent autoloading of ldiscs
	ipv6: Fix dangling pointer when ipv6 fragment
	ipv6: sit: reset ip header pointer in ipip6_rcv
	kcm: switch order of device registration to fix a crash
	net: rds: force to destroy connection if t_sock is NULL in rds_tcp_kill_sock().
	openvswitch: fix flow actions reallocation
	qmi_wwan: add Olicard 600
	sctp: initialize _pad of sockaddr_in before copying to user memory
	tcp: Ensure DCTCP reacts to losses
	vrf: check accept_source_route on the original netdevice
	bnxt_en: Reset device on RX buffer errors.
	bnxt_en: Improve RX consumer index validity check.
	net/mlx5e: Add a lock on tir list
	netns: provide pure entropy for net_hash_mix()
	net: ethtool: not call vzalloc for zero sized memory request
	ip6_tunnel: Match to ARPHRD_TUNNEL6 for dev type
	ALSA: seq: Fix OOB-reads from strlcpy
	parisc: Detect QEMU earlier in boot process
	include/linux/bitrev.h: fix constant bitrev
	ASoC: fsl_esai: fix channel swap issue when stream starts
	Btrfs: do not allow trimming when a fs is mounted with the nologreplay option
	block: do not leak memory in bio_copy_user_iov()
	genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent()
	virtio: Honour 'may_reduce_num' in vring_create_virtqueue
	ARM: dts: at91: Fix typo in ISC_D0 on PC9
	arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value
	parisc: Use cr16 interval timers unconditionally on qemu
	xen: Prevent buffer overflow in privcmd ioctl
	sched/fair: Do not re-read ->h_load_next during hierarchical load calculation
	xtensa: fix return_address
	PCI: Add function 1 DMA alias quirk for Marvell 9170 SATA controller
	Linux 4.9.169

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2019-04-18 02:14:10 +03:00

290 lines
6.2 KiB
C

/*
* Kernel and userspace stack tracing.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2013 Tensilica Inc.
* Copyright (C) 2015 Cadence Design Systems Inc.
*/
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/stacktrace.h>
#include <asm/stacktrace.h>
#include <asm/traps.h>
#include <asm/uaccess.h>
#if IS_ENABLED(CONFIG_OPROFILE) || IS_ENABLED(CONFIG_PERF_EVENTS)
/* Address of common_exception_return, used to check the
* transition from kernel to user space.
*/
extern int common_exception_return;
/* A struct that maps to the part of the frame containing the a0 and
* a1 registers.
*/
struct frame_start {
unsigned long a0;
unsigned long a1;
};
void xtensa_backtrace_user(struct pt_regs *regs, unsigned int depth,
int (*ufn)(struct stackframe *frame, void *data),
void *data)
{
unsigned long windowstart = regs->windowstart;
unsigned long windowbase = regs->windowbase;
unsigned long a0 = regs->areg[0];
unsigned long a1 = regs->areg[1];
unsigned long pc = regs->pc;
struct stackframe frame;
int index;
if (!depth--)
return;
frame.pc = pc;
frame.sp = a1;
if (pc == 0 || pc >= TASK_SIZE || ufn(&frame, data))
return;
/* Two steps:
*
* 1. Look through the register window for the
* previous PCs in the call trace.
*
* 2. Look on the stack.
*/
/* Step 1. */
/* Rotate WINDOWSTART to move the bit corresponding to
* the current window to the bit #0.
*/
windowstart = (windowstart << WSBITS | windowstart) >> windowbase;
/* Look for bits that are set, they correspond to
* valid windows.
*/
for (index = WSBITS - 1; (index > 0) && depth; depth--, index--)
if (windowstart & (1 << index)) {
/* Get the PC from a0 and a1. */
pc = MAKE_PC_FROM_RA(a0, pc);
/* Read a0 and a1 from the
* corresponding position in AREGs.
*/
a0 = regs->areg[index * 4];
a1 = regs->areg[index * 4 + 1];
frame.pc = pc;
frame.sp = a1;
if (pc == 0 || pc >= TASK_SIZE || ufn(&frame, data))
return;
}
/* Step 2. */
/* We are done with the register window, we need to
* look through the stack.
*/
if (!depth)
return;
/* Start from the a1 register. */
/* a1 = regs->areg[1]; */
while (a0 != 0 && depth--) {
struct frame_start frame_start;
/* Get the location for a1, a0 for the
* previous frame from the current a1.
*/
unsigned long *psp = (unsigned long *)a1;
psp -= 4;
/* Check if the region is OK to access. */
if (!access_ok(VERIFY_READ, psp, sizeof(frame_start)))
return;
/* Copy a1, a0 from user space stack frame. */
if (__copy_from_user_inatomic(&frame_start, psp,
sizeof(frame_start)))
return;
pc = MAKE_PC_FROM_RA(a0, pc);
a0 = frame_start.a0;
a1 = frame_start.a1;
frame.pc = pc;
frame.sp = a1;
if (pc == 0 || pc >= TASK_SIZE || ufn(&frame, data))
return;
}
}
EXPORT_SYMBOL(xtensa_backtrace_user);
void xtensa_backtrace_kernel(struct pt_regs *regs, unsigned int depth,
int (*kfn)(struct stackframe *frame, void *data),
int (*ufn)(struct stackframe *frame, void *data),
void *data)
{
unsigned long pc = regs->depc > VALID_DOUBLE_EXCEPTION_ADDRESS ?
regs->depc : regs->pc;
unsigned long sp_start, sp_end;
unsigned long a0 = regs->areg[0];
unsigned long a1 = regs->areg[1];
sp_start = a1 & ~(THREAD_SIZE - 1);
sp_end = sp_start + THREAD_SIZE;
/* Spill the register window to the stack first. */
spill_registers();
/* Read the stack frames one by one and create the PC
* from the a0 and a1 registers saved there.
*/
while (a1 > sp_start && a1 < sp_end && depth--) {
struct stackframe frame;
unsigned long *psp = (unsigned long *)a1;
frame.pc = pc;
frame.sp = a1;
if (kernel_text_address(pc) && kfn(&frame, data))
return;
if (pc == (unsigned long)&common_exception_return) {
regs = (struct pt_regs *)a1;
if (user_mode(regs)) {
if (ufn == NULL)
return;
xtensa_backtrace_user(regs, depth, ufn, data);
return;
}
a0 = regs->areg[0];
a1 = regs->areg[1];
continue;
}
sp_start = a1;
pc = MAKE_PC_FROM_RA(a0, pc);
a0 = *(psp - 4);
a1 = *(psp - 3);
}
}
EXPORT_SYMBOL(xtensa_backtrace_kernel);
#endif
void walk_stackframe(unsigned long *sp,
int (*fn)(struct stackframe *frame, void *data),
void *data)
{
unsigned long a0, a1;
unsigned long sp_end;
a1 = (unsigned long)sp;
sp_end = ALIGN(a1, THREAD_SIZE);
spill_registers();
while (a1 < sp_end) {
struct stackframe frame;
sp = (unsigned long *)a1;
a0 = *(sp - 4);
a1 = *(sp - 3);
if (a1 <= (unsigned long)sp)
break;
frame.pc = MAKE_PC_FROM_RA(a0, a1);
frame.sp = a1;
if (fn(&frame, data))
return;
}
}
#ifdef CONFIG_STACKTRACE
struct stack_trace_data {
struct stack_trace *trace;
unsigned skip;
};
static int stack_trace_cb(struct stackframe *frame, void *data)
{
struct stack_trace_data *trace_data = data;
struct stack_trace *trace = trace_data->trace;
if (trace_data->skip) {
--trace_data->skip;
return 0;
}
if (!kernel_text_address(frame->pc))
return 0;
trace->entries[trace->nr_entries++] = frame->pc;
return trace->nr_entries >= trace->max_entries;
}
void save_stack_trace_tsk(struct task_struct *task, struct stack_trace *trace)
{
struct stack_trace_data trace_data = {
.trace = trace,
.skip = trace->skip,
};
walk_stackframe(stack_pointer(task), stack_trace_cb, &trace_data);
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
void save_stack_trace(struct stack_trace *trace)
{
save_stack_trace_tsk(current, trace);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
#endif
#ifdef CONFIG_FRAME_POINTER
struct return_addr_data {
unsigned long addr;
unsigned skip;
};
static int return_address_cb(struct stackframe *frame, void *data)
{
struct return_addr_data *r = data;
if (r->skip) {
--r->skip;
return 0;
}
if (!kernel_text_address(frame->pc))
return 0;
r->addr = frame->pc;
return 1;
}
/*
* level == 0 is for the return address from the caller of this function,
* not from this function itself.
*/
unsigned long return_address(unsigned level)
{
struct return_addr_data r = {
.skip = level,
};
walk_stackframe(stack_pointer(NULL), return_address_cb, &r);
return r.addr;
}
EXPORT_SYMBOL(return_address);
#endif