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-rw-r--r--arch/x86/Kconfig2
-rw-r--r--arch/x86/Makefile2
-rw-r--r--arch/x86/boot/compressed/Makefile2
-rw-r--r--arch/x86/entry/entry_32.S30
-rw-r--r--arch/x86/entry/entry_64.S11
-rw-r--r--arch/x86/include/asm/mce.h1
-rw-r--r--arch/x86/kernel/alternative.c9
-rw-r--r--arch/x86/kernel/cpu/mcheck/mce.c13
-rw-r--r--arch/x86/kernel/ftrace.c20
-rw-r--r--arch/x86/kernel/kprobes/core.c9
-rw-r--r--arch/x86/kernel/setup.c4
-rw-r--r--arch/x86/kernel/unwind_frame.c49
-rw-r--r--arch/x86/mm/pageattr.c2
-rw-r--r--arch/x86/mm/pat.c9
14 files changed, 112 insertions, 51 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index cd18994a9555..4ccfacc7232a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -360,7 +360,7 @@ config SMP
Management" code will be disabled if you say Y here.
See also <file:Documentation/x86/i386/IO-APIC.txt>,
- <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
+ <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
<http://www.tldp.org/docs.html#howto>.
If you don't know what to do here, say N.
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 5851411e60fb..bf240b920473 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -159,7 +159,7 @@ ifdef CONFIG_FUNCTION_GRAPH_TRACER
# If '-Os' is enabled, disable it and print a warning.
ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
undefine CONFIG_CC_OPTIMIZE_FOR_SIZE
- $(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE. Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.)
+ $(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE. Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.)
endif
endif
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 44163e8c3868..2c860ad4fe06 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -94,7 +94,7 @@ vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
quiet_cmd_check_data_rel = DATAREL $@
define cmd_check_data_rel
for obj in $(filter %.o,$^); do \
- readelf -S $$obj | grep -qF .rel.local && { \
+ ${CROSS_COMPILE}readelf -S $$obj | grep -qF .rel.local && { \
echo "error: $$obj has data relocations!" >&2; \
exit 1; \
} || true; \
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 50bc26949e9e..48ef7bb32c42 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -252,6 +252,23 @@ ENTRY(__switch_to_asm)
END(__switch_to_asm)
/*
+ * The unwinder expects the last frame on the stack to always be at the same
+ * offset from the end of the page, which allows it to validate the stack.
+ * Calling schedule_tail() directly would break that convention because its an
+ * asmlinkage function so its argument has to be pushed on the stack. This
+ * wrapper creates a proper "end of stack" frame header before the call.
+ */
+ENTRY(schedule_tail_wrapper)
+ FRAME_BEGIN
+
+ pushl %eax
+ call schedule_tail
+ popl %eax
+
+ FRAME_END
+ ret
+ENDPROC(schedule_tail_wrapper)
+/*
* A newly forked process directly context switches into this address.
*
* eax: prev task we switched from
@@ -259,24 +276,15 @@ END(__switch_to_asm)
* edi: kernel thread arg
*/
ENTRY(ret_from_fork)
- FRAME_BEGIN /* help unwinder find end of stack */
-
- /*
- * schedule_tail() is asmlinkage so we have to put its 'prev' argument
- * on the stack.
- */
- pushl %eax
- call schedule_tail
- popl %eax
+ call schedule_tail_wrapper
testl %ebx, %ebx
jnz 1f /* kernel threads are uncommon */
2:
/* When we fork, we trace the syscall return in the child, too. */
- leal FRAME_OFFSET(%esp), %eax
+ movl %esp, %eax
call syscall_return_slowpath
- FRAME_END
jmp restore_all
/* kernel thread */
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 607d72c4a485..4a4c0834f965 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -36,7 +36,6 @@
#include <asm/smap.h>
#include <asm/pgtable_types.h>
#include <asm/export.h>
-#include <asm/frame.h>
#include <linux/err.h>
.code64
@@ -406,19 +405,17 @@ END(__switch_to_asm)
* r12: kernel thread arg
*/
ENTRY(ret_from_fork)
- FRAME_BEGIN /* help unwinder find end of stack */
movq %rax, %rdi
- call schedule_tail /* rdi: 'prev' task parameter */
+ call schedule_tail /* rdi: 'prev' task parameter */
- testq %rbx, %rbx /* from kernel_thread? */
- jnz 1f /* kernel threads are uncommon */
+ testq %rbx, %rbx /* from kernel_thread? */
+ jnz 1f /* kernel threads are uncommon */
2:
- leaq FRAME_OFFSET(%rsp),%rdi /* pt_regs pointer */
+ movq %rsp, %rdi
call syscall_return_slowpath /* returns with IRQs disabled */
TRACE_IRQS_ON /* user mode is traced as IRQS on */
SWAPGS
- FRAME_END
jmp restore_regs_and_iret
1:
diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h
index 4fd5195deed0..3f9a3d2a5209 100644
--- a/arch/x86/include/asm/mce.h
+++ b/arch/x86/include/asm/mce.h
@@ -266,6 +266,7 @@ static inline int umc_normaddr_to_sysaddr(u64 norm_addr, u16 nid, u8 umc, u64 *s
#endif
int mce_available(struct cpuinfo_x86 *c);
+bool mce_is_memory_error(struct mce *m);
DECLARE_PER_CPU(unsigned, mce_exception_count);
DECLARE_PER_CPU(unsigned, mce_poll_count);
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index c5b8f760473c..32e14d137416 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -409,8 +409,13 @@ void __init_or_module noinline apply_alternatives(struct alt_instr *start,
memcpy(insnbuf, replacement, a->replacementlen);
insnbuf_sz = a->replacementlen;
- /* 0xe8 is a relative jump; fix the offset. */
- if (*insnbuf == 0xe8 && a->replacementlen == 5) {
+ /*
+ * 0xe8 is a relative jump; fix the offset.
+ *
+ * Instruction length is checked before the opcode to avoid
+ * accessing uninitialized bytes for zero-length replacements.
+ */
+ if (a->replacementlen == 5 && *insnbuf == 0xe8) {
*(s32 *)(insnbuf + 1) += replacement - instr;
DPRINTK("Fix CALL offset: 0x%x, CALL 0x%lx",
*(s32 *)(insnbuf + 1),
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 5abd4bf73d6e..5cfbaeb6529a 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -499,16 +499,14 @@ static int mce_usable_address(struct mce *m)
return 1;
}
-static bool memory_error(struct mce *m)
+bool mce_is_memory_error(struct mce *m)
{
- struct cpuinfo_x86 *c = &boot_cpu_data;
-
- if (c->x86_vendor == X86_VENDOR_AMD) {
+ if (m->cpuvendor == X86_VENDOR_AMD) {
/* ErrCodeExt[20:16] */
u8 xec = (m->status >> 16) & 0x1f;
return (xec == 0x0 || xec == 0x8);
- } else if (c->x86_vendor == X86_VENDOR_INTEL) {
+ } else if (m->cpuvendor == X86_VENDOR_INTEL) {
/*
* Intel SDM Volume 3B - 15.9.2 Compound Error Codes
*
@@ -529,6 +527,7 @@ static bool memory_error(struct mce *m)
return false;
}
+EXPORT_SYMBOL_GPL(mce_is_memory_error);
static bool cec_add_mce(struct mce *m)
{
@@ -536,7 +535,7 @@ static bool cec_add_mce(struct mce *m)
return false;
/* We eat only correctable DRAM errors with usable addresses. */
- if (memory_error(m) &&
+ if (mce_is_memory_error(m) &&
!(m->status & MCI_STATUS_UC) &&
mce_usable_address(m))
if (!cec_add_elem(m->addr >> PAGE_SHIFT))
@@ -713,7 +712,7 @@ bool machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
severity = mce_severity(&m, mca_cfg.tolerant, NULL, false);
- if (severity == MCE_DEFERRED_SEVERITY && memory_error(&m))
+ if (severity == MCE_DEFERRED_SEVERITY && mce_is_memory_error(&m))
if (m.status & MCI_STATUS_ADDRV)
m.severity = severity;
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 0651e974dcb3..9bef1bbeba63 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -689,8 +689,12 @@ static inline void *alloc_tramp(unsigned long size)
{
return module_alloc(size);
}
-static inline void tramp_free(void *tramp)
+static inline void tramp_free(void *tramp, int size)
{
+ int npages = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+ set_memory_nx((unsigned long)tramp, npages);
+ set_memory_rw((unsigned long)tramp, npages);
module_memfree(tramp);
}
#else
@@ -699,7 +703,7 @@ static inline void *alloc_tramp(unsigned long size)
{
return NULL;
}
-static inline void tramp_free(void *tramp) { }
+static inline void tramp_free(void *tramp, int size) { }
#endif
/* Defined as markers to the end of the ftrace default trampolines */
@@ -771,7 +775,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
/* Copy ftrace_caller onto the trampoline memory */
ret = probe_kernel_read(trampoline, (void *)start_offset, size);
if (WARN_ON(ret < 0)) {
- tramp_free(trampoline);
+ tramp_free(trampoline, *tramp_size);
return 0;
}
@@ -797,7 +801,7 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size)
/* Are we pointing to the reference? */
if (WARN_ON(memcmp(op_ptr.op, op_ref, 3) != 0)) {
- tramp_free(trampoline);
+ tramp_free(trampoline, *tramp_size);
return 0;
}
@@ -839,7 +843,7 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops)
unsigned long offset;
unsigned long ip;
unsigned int size;
- int ret;
+ int ret, npages;
if (ops->trampoline) {
/*
@@ -848,11 +852,14 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops)
*/
if (!(ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP))
return;
+ npages = PAGE_ALIGN(ops->trampoline_size) >> PAGE_SHIFT;
+ set_memory_rw(ops->trampoline, npages);
} else {
ops->trampoline = create_trampoline(ops, &size);
if (!ops->trampoline)
return;
ops->trampoline_size = size;
+ npages = PAGE_ALIGN(size) >> PAGE_SHIFT;
}
offset = calc_trampoline_call_offset(ops->flags & FTRACE_OPS_FL_SAVE_REGS);
@@ -863,6 +870,7 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops)
/* Do a safe modify in case the trampoline is executing */
new = ftrace_call_replace(ip, (unsigned long)func);
ret = update_ftrace_func(ip, new);
+ set_memory_ro(ops->trampoline, npages);
/* The update should never fail */
WARN_ON(ret);
@@ -939,7 +947,7 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops)
if (!ops || !(ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP))
return;
- tramp_free((void *)ops->trampoline);
+ tramp_free((void *)ops->trampoline, ops->trampoline_size);
ops->trampoline = 0;
}
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 5b2bbfbb3712..6b877807598b 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -52,6 +52,7 @@
#include <linux/ftrace.h>
#include <linux/frame.h>
#include <linux/kasan.h>
+#include <linux/moduleloader.h>
#include <asm/text-patching.h>
#include <asm/cacheflush.h>
@@ -417,6 +418,14 @@ static void prepare_boost(struct kprobe *p, struct insn *insn)
}
}
+/* Recover page to RW mode before releasing it */
+void free_insn_page(void *page)
+{
+ set_memory_nx((unsigned long)page & PAGE_MASK, 1);
+ set_memory_rw((unsigned long)page & PAGE_MASK, 1);
+ module_memfree(page);
+}
+
static int arch_copy_kprobe(struct kprobe *p)
{
struct insn insn;
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 0b4d3c686b1e..f81823695014 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -980,8 +980,6 @@ void __init setup_arch(char **cmdline_p)
*/
x86_configure_nx();
- simple_udelay_calibration();
-
parse_early_param();
#ifdef CONFIG_MEMORY_HOTPLUG
@@ -1041,6 +1039,8 @@ void __init setup_arch(char **cmdline_p)
*/
init_hypervisor_platform();
+ simple_udelay_calibration();
+
x86_init.resources.probe_roms();
/* after parse_early_param, so could debug it */
diff --git a/arch/x86/kernel/unwind_frame.c b/arch/x86/kernel/unwind_frame.c
index 82c6d7f1fd73..b9389d72b2f7 100644
--- a/arch/x86/kernel/unwind_frame.c
+++ b/arch/x86/kernel/unwind_frame.c
@@ -104,6 +104,11 @@ static inline unsigned long *last_frame(struct unwind_state *state)
return (unsigned long *)task_pt_regs(state->task) - 2;
}
+static bool is_last_frame(struct unwind_state *state)
+{
+ return state->bp == last_frame(state);
+}
+
#ifdef CONFIG_X86_32
#define GCC_REALIGN_WORDS 3
#else
@@ -115,16 +120,15 @@ static inline unsigned long *last_aligned_frame(struct unwind_state *state)
return last_frame(state) - GCC_REALIGN_WORDS;
}
-static bool is_last_task_frame(struct unwind_state *state)
+static bool is_last_aligned_frame(struct unwind_state *state)
{
unsigned long *last_bp = last_frame(state);
unsigned long *aligned_bp = last_aligned_frame(state);
/*
- * We have to check for the last task frame at two different locations
- * because gcc can occasionally decide to realign the stack pointer and
- * change the offset of the stack frame in the prologue of a function
- * called by head/entry code. Examples:
+ * GCC can occasionally decide to realign the stack pointer and change
+ * the offset of the stack frame in the prologue of a function called
+ * by head/entry code. Examples:
*
* <start_secondary>:
* push %edi
@@ -141,11 +145,38 @@ static bool is_last_task_frame(struct unwind_state *state)
* push %rbp
* mov %rsp,%rbp
*
- * Note that after aligning the stack, it pushes a duplicate copy of
- * the return address before pushing the frame pointer.
+ * After aligning the stack, it pushes a duplicate copy of the return
+ * address before pushing the frame pointer.
+ */
+ return (state->bp == aligned_bp && *(aligned_bp + 1) == *(last_bp + 1));
+}
+
+static bool is_last_ftrace_frame(struct unwind_state *state)
+{
+ unsigned long *last_bp = last_frame(state);
+ unsigned long *last_ftrace_bp = last_bp - 3;
+
+ /*
+ * When unwinding from an ftrace handler of a function called by entry
+ * code, the stack layout of the last frame is:
+ *
+ * bp
+ * parent ret addr
+ * bp
+ * function ret addr
+ * parent ret addr
+ * pt_regs
+ * -----------------
*/
- return (state->bp == last_bp ||
- (state->bp == aligned_bp && *(aligned_bp+1) == *(last_bp+1)));
+ return (state->bp == last_ftrace_bp &&
+ *state->bp == *(state->bp + 2) &&
+ *(state->bp + 1) == *(state->bp + 4));
+}
+
+static bool is_last_task_frame(struct unwind_state *state)
+{
+ return is_last_frame(state) || is_last_aligned_frame(state) ||
+ is_last_ftrace_frame(state);
}
/*
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 1dcd2be4cce4..c8520b2c62d2 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -186,7 +186,7 @@ static void cpa_flush_range(unsigned long start, int numpages, int cache)
unsigned int i, level;
unsigned long addr;
- BUG_ON(irqs_disabled());
+ BUG_ON(irqs_disabled() && !early_boot_irqs_disabled);
WARN_ON(PAGE_ALIGN(start) != start);
on_each_cpu(__cpa_flush_range, NULL, 1);
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 9b78685b66e6..83a59a67757a 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -65,9 +65,11 @@ static int __init nopat(char *str)
}
early_param("nopat", nopat);
+static bool __read_mostly __pat_initialized = false;
+
bool pat_enabled(void)
{
- return !!__pat_enabled;
+ return __pat_initialized;
}
EXPORT_SYMBOL_GPL(pat_enabled);
@@ -225,13 +227,14 @@ static void pat_bsp_init(u64 pat)
}
wrmsrl(MSR_IA32_CR_PAT, pat);
+ __pat_initialized = true;
__init_cache_modes(pat);
}
static void pat_ap_init(u64 pat)
{
- if (!boot_cpu_has(X86_FEATURE_PAT)) {
+ if (!this_cpu_has(X86_FEATURE_PAT)) {
/*
* If this happens we are on a secondary CPU, but switched to
* PAT on the boot CPU. We have no way to undo PAT.
@@ -306,7 +309,7 @@ void pat_init(void)
u64 pat;
struct cpuinfo_x86 *c = &boot_cpu_data;
- if (!pat_enabled()) {
+ if (!__pat_enabled) {
init_cache_modes();
return;
}
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