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Diffstat (limited to 'arch/x86/kernel/entry_64.S')
-rw-r--r--arch/x86/kernel/entry_64.S221
1 files changed, 142 insertions, 79 deletions
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index ce87e3d10c63..0c58952d64e8 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -56,6 +56,7 @@
#include <asm/ftrace.h>
#include <asm/percpu.h>
#include <asm/asm.h>
+#include <asm/rcu.h>
#include <asm/smap.h>
#include <linux/err.h>
@@ -69,25 +70,51 @@
.section .entry.text, "ax"
#ifdef CONFIG_FUNCTION_TRACER
+
+#ifdef CC_USING_FENTRY
+# define function_hook __fentry__
+#else
+# define function_hook mcount
+#endif
+
#ifdef CONFIG_DYNAMIC_FTRACE
-ENTRY(mcount)
+
+ENTRY(function_hook)
retq
-END(mcount)
+END(function_hook)
+
+/* skip is set if stack has been adjusted */
+.macro ftrace_caller_setup skip=0
+ MCOUNT_SAVE_FRAME \skip
+
+ /* Load the ftrace_ops into the 3rd parameter */
+ leaq function_trace_op, %rdx
+
+ /* Load ip into the first parameter */
+ movq RIP(%rsp), %rdi
+ subq $MCOUNT_INSN_SIZE, %rdi
+ /* Load the parent_ip into the second parameter */
+#ifdef CC_USING_FENTRY
+ movq SS+16(%rsp), %rsi
+#else
+ movq 8(%rbp), %rsi
+#endif
+.endm
ENTRY(ftrace_caller)
+ /* Check if tracing was disabled (quick check) */
cmpl $0, function_trace_stop
jne ftrace_stub
- MCOUNT_SAVE_FRAME
-
- movq 0x38(%rsp), %rdi
- movq 8(%rbp), %rsi
- subq $MCOUNT_INSN_SIZE, %rdi
+ ftrace_caller_setup
+ /* regs go into 4th parameter (but make it NULL) */
+ movq $0, %rcx
GLOBAL(ftrace_call)
call ftrace_stub
MCOUNT_RESTORE_FRAME
+ftrace_return:
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
GLOBAL(ftrace_graph_call)
@@ -98,8 +125,78 @@ GLOBAL(ftrace_stub)
retq
END(ftrace_caller)
+ENTRY(ftrace_regs_caller)
+ /* Save the current flags before compare (in SS location)*/
+ pushfq
+
+ /* Check if tracing was disabled (quick check) */
+ cmpl $0, function_trace_stop
+ jne ftrace_restore_flags
+
+ /* skip=8 to skip flags saved in SS */
+ ftrace_caller_setup 8
+
+ /* Save the rest of pt_regs */
+ movq %r15, R15(%rsp)
+ movq %r14, R14(%rsp)
+ movq %r13, R13(%rsp)
+ movq %r12, R12(%rsp)
+ movq %r11, R11(%rsp)
+ movq %r10, R10(%rsp)
+ movq %rbp, RBP(%rsp)
+ movq %rbx, RBX(%rsp)
+ /* Copy saved flags */
+ movq SS(%rsp), %rcx
+ movq %rcx, EFLAGS(%rsp)
+ /* Kernel segments */
+ movq $__KERNEL_DS, %rcx
+ movq %rcx, SS(%rsp)
+ movq $__KERNEL_CS, %rcx
+ movq %rcx, CS(%rsp)
+ /* Stack - skipping return address */
+ leaq SS+16(%rsp), %rcx
+ movq %rcx, RSP(%rsp)
+
+ /* regs go into 4th parameter */
+ leaq (%rsp), %rcx
+
+GLOBAL(ftrace_regs_call)
+ call ftrace_stub
+
+ /* Copy flags back to SS, to restore them */
+ movq EFLAGS(%rsp), %rax
+ movq %rax, SS(%rsp)
+
+ /* Handlers can change the RIP */
+ movq RIP(%rsp), %rax
+ movq %rax, SS+8(%rsp)
+
+ /* restore the rest of pt_regs */
+ movq R15(%rsp), %r15
+ movq R14(%rsp), %r14
+ movq R13(%rsp), %r13
+ movq R12(%rsp), %r12
+ movq R10(%rsp), %r10
+ movq RBP(%rsp), %rbp
+ movq RBX(%rsp), %rbx
+
+ /* skip=8 to skip flags saved in SS */
+ MCOUNT_RESTORE_FRAME 8
+
+ /* Restore flags */
+ popfq
+
+ jmp ftrace_return
+ftrace_restore_flags:
+ popfq
+ jmp ftrace_stub
+
+END(ftrace_regs_caller)
+
+
#else /* ! CONFIG_DYNAMIC_FTRACE */
-ENTRY(mcount)
+
+ENTRY(function_hook)
cmpl $0, function_trace_stop
jne ftrace_stub
@@ -120,8 +217,12 @@ GLOBAL(ftrace_stub)
trace:
MCOUNT_SAVE_FRAME
- movq 0x38(%rsp), %rdi
+ movq RIP(%rsp), %rdi
+#ifdef CC_USING_FENTRY
+ movq SS+16(%rsp), %rsi
+#else
movq 8(%rbp), %rsi
+#endif
subq $MCOUNT_INSN_SIZE, %rdi
call *ftrace_trace_function
@@ -129,20 +230,22 @@ trace:
MCOUNT_RESTORE_FRAME
jmp ftrace_stub
-END(mcount)
+END(function_hook)
#endif /* CONFIG_DYNAMIC_FTRACE */
#endif /* CONFIG_FUNCTION_TRACER */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
ENTRY(ftrace_graph_caller)
- cmpl $0, function_trace_stop
- jne ftrace_stub
-
MCOUNT_SAVE_FRAME
+#ifdef CC_USING_FENTRY
+ leaq SS+16(%rsp), %rdi
+ movq $0, %rdx /* No framepointers needed */
+#else
leaq 8(%rbp), %rdi
- movq 0x38(%rsp), %rsi
movq (%rbp), %rdx
+#endif
+ movq RIP(%rsp), %rsi
subq $MCOUNT_INSN_SIZE, %rsi
call prepare_ftrace_return
@@ -343,15 +446,15 @@ ENDPROC(native_usergs_sysret64)
.macro SAVE_ARGS_IRQ
cld
/* start from rbp in pt_regs and jump over */
- movq_cfi rdi, RDI-RBP
- movq_cfi rsi, RSI-RBP
- movq_cfi rdx, RDX-RBP
- movq_cfi rcx, RCX-RBP
- movq_cfi rax, RAX-RBP
- movq_cfi r8, R8-RBP
- movq_cfi r9, R9-RBP
- movq_cfi r10, R10-RBP
- movq_cfi r11, R11-RBP
+ movq_cfi rdi, (RDI-RBP)
+ movq_cfi rsi, (RSI-RBP)
+ movq_cfi rdx, (RDX-RBP)
+ movq_cfi rcx, (RCX-RBP)
+ movq_cfi rax, (RAX-RBP)
+ movq_cfi r8, (R8-RBP)
+ movq_cfi r9, (R9-RBP)
+ movq_cfi r10, (R10-RBP)
+ movq_cfi r11, (R11-RBP)
/* Save rbp so that we can unwind from get_irq_regs() */
movq_cfi rbp, 0
@@ -385,7 +488,7 @@ ENDPROC(native_usergs_sysret64)
.endm
ENTRY(save_rest)
- PARTIAL_FRAME 1 REST_SKIP+8
+ PARTIAL_FRAME 1 (REST_SKIP+8)
movq 5*8+16(%rsp), %r11 /* save return address */
movq_cfi rbx, RBX+16
movq_cfi rbp, RBP+16
@@ -441,7 +544,7 @@ ENTRY(ret_from_fork)
LOCK ; btr $TIF_FORK,TI_flags(%r8)
- pushq_cfi kernel_eflags(%rip)
+ pushq_cfi $0x0002
popfq_cfi # reset kernel eflags
call schedule_tail # rdi: 'prev' task parameter
@@ -451,7 +554,7 @@ ENTRY(ret_from_fork)
RESTORE_REST
testl $3, CS-ARGOFFSET(%rsp) # from kernel_thread?
- jz retint_restore_args
+ jz 1f
testl $_TIF_IA32, TI_flags(%rcx) # 32-bit compat task needs IRET
jnz int_ret_from_sys_call
@@ -459,6 +562,14 @@ ENTRY(ret_from_fork)
RESTORE_TOP_OF_STACK %rdi, -ARGOFFSET
jmp ret_from_sys_call # go to the SYSRET fastpath
+1:
+ subq $REST_SKIP, %rsp # leave space for volatiles
+ CFI_ADJUST_CFA_OFFSET REST_SKIP
+ movq %rbp, %rdi
+ call *%rbx
+ movl $0, RAX(%rsp)
+ RESTORE_REST
+ jmp int_ret_from_sys_call
CFI_ENDPROC
END(ret_from_fork)
@@ -567,7 +678,7 @@ sysret_careful:
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
pushq_cfi %rdi
- call schedule
+ SCHEDULE_USER
popq_cfi %rdi
jmp sysret_check
@@ -680,7 +791,7 @@ int_careful:
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
pushq_cfi %rdi
- call schedule
+ SCHEDULE_USER
popq_cfi %rdi
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
@@ -759,7 +870,6 @@ ENTRY(stub_execve)
PARTIAL_FRAME 0
SAVE_REST
FIXUP_TOP_OF_STACK %r11
- movq %rsp, %rcx
call sys_execve
RESTORE_TOP_OF_STACK %r11
movq %rax,RAX(%rsp)
@@ -809,8 +919,7 @@ ENTRY(stub_x32_execve)
PARTIAL_FRAME 0
SAVE_REST
FIXUP_TOP_OF_STACK %r11
- movq %rsp, %rcx
- call sys32_execve
+ call compat_sys_execve
RESTORE_TOP_OF_STACK %r11
movq %rax,RAX(%rsp)
RESTORE_REST
@@ -977,7 +1086,7 @@ retint_careful:
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
pushq_cfi %rdi
- call schedule
+ SCHEDULE_USER
popq_cfi %rdi
GET_THREAD_INFO(%rcx)
DISABLE_INTERRUPTS(CLBR_NONE)
@@ -1215,52 +1324,6 @@ bad_gs:
jmp 2b
.previous
-ENTRY(kernel_thread_helper)
- pushq $0 # fake return address
- CFI_STARTPROC
- /*
- * Here we are in the child and the registers are set as they were
- * at kernel_thread() invocation in the parent.
- */
- call *%rsi
- # exit
- mov %eax, %edi
- call do_exit
- ud2 # padding for call trace
- CFI_ENDPROC
-END(kernel_thread_helper)
-
-/*
- * execve(). This function needs to use IRET, not SYSRET, to set up all state properly.
- *
- * C extern interface:
- * extern long execve(const char *name, char **argv, char **envp)
- *
- * asm input arguments:
- * rdi: name, rsi: argv, rdx: envp
- *
- * We want to fallback into:
- * extern long sys_execve(const char *name, char **argv,char **envp, struct pt_regs *regs)
- *
- * do_sys_execve asm fallback arguments:
- * rdi: name, rsi: argv, rdx: envp, rcx: fake frame on the stack
- */
-ENTRY(kernel_execve)
- CFI_STARTPROC
- FAKE_STACK_FRAME $0
- SAVE_ALL
- movq %rsp,%rcx
- call sys_execve
- movq %rax, RAX(%rsp)
- RESTORE_REST
- testq %rax,%rax
- je int_ret_from_sys_call
- RESTORE_ARGS
- UNFAKE_STACK_FRAME
- ret
- CFI_ENDPROC
-END(kernel_execve)
-
/* Call softirq on interrupt stack. Interrupts are off. */
ENTRY(call_softirq)
CFI_STARTPROC
@@ -1458,7 +1521,7 @@ paranoid_userspace:
paranoid_schedule:
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_ANY)
- call schedule
+ SCHEDULE_USER
DISABLE_INTERRUPTS(CLBR_ANY)
TRACE_IRQS_OFF
jmp paranoid_userspace