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-rw-r--r--arch/arm64/kernel/Makefile7
-rw-r--r--arch/arm64/kernel/arm64ksyms.c9
-rw-r--r--arch/arm64/kernel/entry-fpsimd.S24
-rw-r--r--arch/arm64/kernel/entry-ftrace.S218
-rw-r--r--arch/arm64/kernel/entry.S90
-rw-r--r--arch/arm64/kernel/fpsimd.c186
-rw-r--r--arch/arm64/kernel/ftrace.c176
-rw-r--r--arch/arm64/kernel/head.S8
-rw-r--r--arch/arm64/kernel/hw_breakpoint.c2
-rw-r--r--arch/arm64/kernel/process.c49
-rw-r--r--arch/arm64/kernel/ptrace.c62
-rw-r--r--arch/arm64/kernel/return_address.c55
-rw-r--r--arch/arm64/kernel/setup.c16
-rw-r--r--arch/arm64/kernel/signal.c52
-rw-r--r--arch/arm64/kernel/signal32.c16
-rw-r--r--arch/arm64/kernel/smp.c19
-rw-r--r--arch/arm64/kernel/smp_spin_table.c39
-rw-r--r--arch/arm64/kernel/stacktrace.c2
-rw-r--r--arch/arm64/kernel/time.c3
-rw-r--r--arch/arm64/kernel/topology.c212
-rw-r--r--arch/arm64/kernel/traps.c7
-rw-r--r--arch/arm64/kernel/vmlinux.lds.S2
22 files changed, 1063 insertions, 191 deletions
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index ba5e17a..cdaedad 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -7,14 +7,19 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
CFLAGS_efi-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) \
-I$(src)/../../../scripts/dtc/libfdt
+CFLAGS_REMOVE_ftrace.o = -pg
+CFLAGS_REMOVE_insn.o = -pg
+CFLAGS_REMOVE_return_address.o = -pg
+
# Object file lists.
arm64-obj-y := cputable.o debug-monitors.o entry.o irq.o fpsimd.o \
entry-fpsimd.o process.o ptrace.o setup.o signal.o \
sys.o stacktrace.o time.o traps.o io.o vdso.o \
- hyp-stub.o psci.o cpu_ops.o insn.o
+ hyp-stub.o psci.o cpu_ops.o insn.o return_address.o
arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \
sys_compat.o
+arm64-obj-$(CONFIG_FUNCTION_TRACER) += ftrace.o entry-ftrace.o
arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o
arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o topology.o
arm64-obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c
index 338b568..a85843d 100644
--- a/arch/arm64/kernel/arm64ksyms.c
+++ b/arch/arm64/kernel/arm64ksyms.c
@@ -44,10 +44,15 @@ EXPORT_SYMBOL(memstart_addr);
/* string / mem functions */
EXPORT_SYMBOL(strchr);
EXPORT_SYMBOL(strrchr);
+EXPORT_SYMBOL(strcmp);
+EXPORT_SYMBOL(strncmp);
+EXPORT_SYMBOL(strlen);
+EXPORT_SYMBOL(strnlen);
EXPORT_SYMBOL(memset);
EXPORT_SYMBOL(memcpy);
EXPORT_SYMBOL(memmove);
EXPORT_SYMBOL(memchr);
+EXPORT_SYMBOL(memcmp);
/* atomic bitops */
EXPORT_SYMBOL(set_bit);
@@ -56,3 +61,7 @@ EXPORT_SYMBOL(clear_bit);
EXPORT_SYMBOL(test_and_clear_bit);
EXPORT_SYMBOL(change_bit);
EXPORT_SYMBOL(test_and_change_bit);
+
+#ifdef CONFIG_FUNCTION_TRACER
+EXPORT_SYMBOL(_mcount);
+#endif
diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S
index 6a27cd6..d358cca 100644
--- a/arch/arm64/kernel/entry-fpsimd.S
+++ b/arch/arm64/kernel/entry-fpsimd.S
@@ -41,3 +41,27 @@ ENTRY(fpsimd_load_state)
fpsimd_restore x0, 8
ret
ENDPROC(fpsimd_load_state)
+
+#ifdef CONFIG_KERNEL_MODE_NEON
+
+/*
+ * Save the bottom n FP registers.
+ *
+ * x0 - pointer to struct fpsimd_partial_state
+ */
+ENTRY(fpsimd_save_partial_state)
+ fpsimd_save_partial x0, 1, 8, 9
+ ret
+ENDPROC(fpsimd_load_partial_state)
+
+/*
+ * Load the bottom n FP registers.
+ *
+ * x0 - pointer to struct fpsimd_partial_state
+ */
+ENTRY(fpsimd_load_partial_state)
+ fpsimd_restore_partial x0, 8, 9
+ ret
+ENDPROC(fpsimd_load_partial_state)
+
+#endif
diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S
new file mode 100644
index 0000000..b051871
--- /dev/null
+++ b/arch/arm64/kernel/entry-ftrace.S
@@ -0,0 +1,218 @@
+/*
+ * arch/arm64/kernel/entry-ftrace.S
+ *
+ * Copyright (C) 2013 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/linkage.h>
+#include <asm/ftrace.h>
+#include <asm/insn.h>
+
+/*
+ * Gcc with -pg will put the following code in the beginning of each function:
+ * mov x0, x30
+ * bl _mcount
+ * [function's body ...]
+ * "bl _mcount" may be replaced to "bl ftrace_caller" or NOP if dynamic
+ * ftrace is enabled.
+ *
+ * Please note that x0 as an argument will not be used here because we can
+ * get lr(x30) of instrumented function at any time by winding up call stack
+ * as long as the kernel is compiled without -fomit-frame-pointer.
+ * (or CONFIG_FRAME_POINTER, this is forced on arm64)
+ *
+ * stack layout after mcount_enter in _mcount():
+ *
+ * current sp/fp => 0:+-----+
+ * in _mcount() | x29 | -> instrumented function's fp
+ * +-----+
+ * | x30 | -> _mcount()'s lr (= instrumented function's pc)
+ * old sp => +16:+-----+
+ * when instrumented | |
+ * function calls | ... |
+ * _mcount() | |
+ * | |
+ * instrumented => +xx:+-----+
+ * function's fp | x29 | -> parent's fp
+ * +-----+
+ * | x30 | -> instrumented function's lr (= parent's pc)
+ * +-----+
+ * | ... |
+ */
+
+ .macro mcount_enter
+ stp x29, x30, [sp, #-16]!
+ mov x29, sp
+ .endm
+
+ .macro mcount_exit
+ ldp x29, x30, [sp], #16
+ ret
+ .endm
+
+ .macro mcount_adjust_addr rd, rn
+ sub \rd, \rn, #AARCH64_INSN_SIZE
+ .endm
+
+ /* for instrumented function's parent */
+ .macro mcount_get_parent_fp reg
+ ldr \reg, [x29]
+ ldr \reg, [\reg]
+ .endm
+
+ /* for instrumented function */
+ .macro mcount_get_pc0 reg
+ mcount_adjust_addr \reg, x30
+ .endm
+
+ .macro mcount_get_pc reg
+ ldr \reg, [x29, #8]
+ mcount_adjust_addr \reg, \reg
+ .endm
+
+ .macro mcount_get_lr reg
+ ldr \reg, [x29]
+ ldr \reg, [\reg, #8]
+ mcount_adjust_addr \reg, \reg
+ .endm
+
+ .macro mcount_get_lr_addr reg
+ ldr \reg, [x29]
+ add \reg, \reg, #8
+ .endm
+
+#ifndef CONFIG_DYNAMIC_FTRACE
+/*
+ * void _mcount(unsigned long return_address)
+ * @return_address: return address to instrumented function
+ *
+ * This function makes calls, if enabled, to:
+ * - tracer function to probe instrumented function's entry,
+ * - ftrace_graph_caller to set up an exit hook
+ */
+ENTRY(_mcount)
+#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ ldr x0, =ftrace_trace_stop
+ ldr x0, [x0] // if ftrace_trace_stop
+ ret // return;
+#endif
+ mcount_enter
+
+ ldr x0, =ftrace_trace_function
+ ldr x2, [x0]
+ adr x0, ftrace_stub
+ cmp x0, x2 // if (ftrace_trace_function
+ b.eq skip_ftrace_call // != ftrace_stub) {
+
+ mcount_get_pc x0 // function's pc
+ mcount_get_lr x1 // function's lr (= parent's pc)
+ blr x2 // (*ftrace_trace_function)(pc, lr);
+
+#ifndef CONFIG_FUNCTION_GRAPH_TRACER
+skip_ftrace_call: // return;
+ mcount_exit // }
+#else
+ mcount_exit // return;
+ // }
+skip_ftrace_call:
+ ldr x1, =ftrace_graph_return
+ ldr x2, [x1] // if ((ftrace_graph_return
+ cmp x0, x2 // != ftrace_stub)
+ b.ne ftrace_graph_caller
+
+ ldr x1, =ftrace_graph_entry // || (ftrace_graph_entry
+ ldr x2, [x1] // != ftrace_graph_entry_stub))
+ ldr x0, =ftrace_graph_entry_stub
+ cmp x0, x2
+ b.ne ftrace_graph_caller // ftrace_graph_caller();
+
+ mcount_exit
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+ENDPROC(_mcount)
+
+#else /* CONFIG_DYNAMIC_FTRACE */
+/*
+ * _mcount() is used to build the kernel with -pg option, but all the branch
+ * instructions to _mcount() are replaced to NOP initially at kernel start up,
+ * and later on, NOP to branch to ftrace_caller() when enabled or branch to
+ * NOP when disabled per-function base.
+ */
+ENTRY(_mcount)
+ ret
+ENDPROC(_mcount)
+
+/*
+ * void ftrace_caller(unsigned long return_address)
+ * @return_address: return address to instrumented function
+ *
+ * This function is a counterpart of _mcount() in 'static' ftrace, and
+ * makes calls to:
+ * - tracer function to probe instrumented function's entry,
+ * - ftrace_graph_caller to set up an exit hook
+ */
+ENTRY(ftrace_caller)
+ mcount_enter
+
+ mcount_get_pc0 x0 // function's pc
+ mcount_get_lr x1 // function's lr
+
+ .global ftrace_call
+ftrace_call: // tracer(pc, lr);
+ nop // This will be replaced with "bl xxx"
+ // where xxx can be any kind of tracer.
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ .global ftrace_graph_call
+ftrace_graph_call: // ftrace_graph_caller();
+ nop // If enabled, this will be replaced
+ // "b ftrace_graph_caller"
+#endif
+
+ mcount_exit
+ENDPROC(ftrace_caller)
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+ENTRY(ftrace_stub)
+ ret
+ENDPROC(ftrace_stub)
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/*
+ * void ftrace_graph_caller(void)
+ *
+ * Called from _mcount() or ftrace_caller() when function_graph tracer is
+ * selected.
+ * This function w/ prepare_ftrace_return() fakes link register's value on
+ * the call stack in order to intercept instrumented function's return path
+ * and run return_to_handler() later on its exit.
+ */
+ENTRY(ftrace_graph_caller)
+ mcount_get_lr_addr x0 // pointer to function's saved lr
+ mcount_get_pc x1 // function's pc
+ mcount_get_parent_fp x2 // parent's fp
+ bl prepare_ftrace_return // prepare_ftrace_return(&lr, pc, fp)
+
+ mcount_exit
+ENDPROC(ftrace_graph_caller)
+
+/*
+ * void return_to_handler(void)
+ *
+ * Run ftrace_return_to_handler() before going back to parent.
+ * @fp is checked against the value passed by ftrace_graph_caller()
+ * only when CONFIG_FUNCTION_GRAPH_FP_TEST is enabled.
+ */
+ENTRY(return_to_handler)
+ str x0, [sp, #-16]!
+ mov x0, x29 // parent's fp
+ bl ftrace_return_to_handler// addr = ftrace_return_to_hander(fp);
+ mov x30, x0 // restore the original return address
+ ldr x0, [sp], #16
+ ret
+END(return_to_handler)
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 39ac630..bf017f4 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -60,6 +60,9 @@
push x0, x1
.if \el == 0
mrs x21, sp_el0
+ get_thread_info tsk // Ensure MDSCR_EL1.SS is clear,
+ ldr x19, [tsk, #TI_FLAGS] // since we can unmask debug
+ disable_step_tsk x19, x20 // exceptions when scheduling.
.else
add x21, sp, #S_FRAME_SIZE
.endif
@@ -259,7 +262,7 @@ el1_da:
* Data abort handling
*/
mrs x0, far_el1
- enable_dbg_if_not_stepping x2
+ enable_dbg
// re-enable interrupts if they were enabled in the aborted context
tbnz x23, #7, 1f // PSR_I_BIT
enable_irq
@@ -275,6 +278,7 @@ el1_sp_pc:
* Stack or PC alignment exception handling
*/
mrs x0, far_el1
+ enable_dbg
mov x1, x25
mov x2, sp
b do_sp_pc_abort
@@ -282,6 +286,7 @@ el1_undef:
/*
* Undefined instruction
*/
+ enable_dbg
mov x0, sp
b do_undefinstr
el1_dbg:
@@ -294,10 +299,11 @@ el1_dbg:
mrs x0, far_el1
mov x2, sp // struct pt_regs
bl do_debug_exception
-
+ enable_dbg
kernel_exit 1
el1_inv:
// TODO: add support for undefined instructions in kernel mode
+ enable_dbg
mov x0, sp
mov x1, #BAD_SYNC
mrs x2, esr_el1
@@ -307,7 +313,7 @@ ENDPROC(el1_sync)
.align 6
el1_irq:
kernel_entry 1
- enable_dbg_if_not_stepping x0
+ enable_dbg
#ifdef CONFIG_TRACE_IRQFLAGS
bl trace_hardirqs_off
#endif
@@ -332,8 +338,7 @@ ENDPROC(el1_irq)
#ifdef CONFIG_PREEMPT
el1_preempt:
mov x24, lr
-1: enable_dbg
- bl preempt_schedule_irq // irq en/disable is done inside
+1: bl preempt_schedule_irq // irq en/disable is done inside
ldr x0, [tsk, #TI_FLAGS] // get new tasks TI_FLAGS
tbnz x0, #TIF_NEED_RESCHED, 1b // needs rescheduling?
ret x24
@@ -349,7 +354,7 @@ el0_sync:
lsr x24, x25, #ESR_EL1_EC_SHIFT // exception class
cmp x24, #ESR_EL1_EC_SVC64 // SVC in 64-bit state
b.eq el0_svc
- adr lr, ret_from_exception
+ adr lr, ret_to_user
cmp x24, #ESR_EL1_EC_DABT_EL0 // data abort in EL0
b.eq el0_da
cmp x24, #ESR_EL1_EC_IABT_EL0 // instruction abort in EL0
@@ -378,7 +383,7 @@ el0_sync_compat:
lsr x24, x25, #ESR_EL1_EC_SHIFT // exception class
cmp x24, #ESR_EL1_EC_SVC32 // SVC in 32-bit state
b.eq el0_svc_compat
- adr lr, ret_from_exception
+ adr lr, ret_to_user
cmp x24, #ESR_EL1_EC_DABT_EL0 // data abort in EL0
b.eq el0_da
cmp x24, #ESR_EL1_EC_IABT_EL0 // instruction abort in EL0
@@ -423,11 +428,8 @@ el0_da:
*/
mrs x0, far_el1
bic x0, x0, #(0xff << 56)
- disable_step x1
- isb
- enable_dbg
// enable interrupts before calling the main handler
- enable_irq
+ enable_dbg_and_irq
mov x1, x25
mov x2, sp
b do_mem_abort
@@ -436,11 +438,8 @@ el0_ia:
* Instruction abort handling
*/
mrs x0, far_el1
- disable_step x1
- isb
- enable_dbg
// enable interrupts before calling the main handler
- enable_irq
+ enable_dbg_and_irq
orr x1, x25, #1 << 24 // use reserved ISS bit for instruction aborts
mov x2, sp
b do_mem_abort
@@ -448,6 +447,7 @@ el0_fpsimd_acc:
/*
* Floating Point or Advanced SIMD access
*/
+ enable_dbg
mov x0, x25
mov x1, sp
b do_fpsimd_acc
@@ -455,6 +455,7 @@ el0_fpsimd_exc:
/*
* Floating Point or Advanced SIMD exception
*/
+ enable_dbg
mov x0, x25
mov x1, sp
b do_fpsimd_exc
@@ -463,11 +464,8 @@ el0_sp_pc:
* Stack or PC alignment exception handling
*/
mrs x0, far_el1
- disable_step x1
- isb
- enable_dbg
// enable interrupts before calling the main handler
- enable_irq
+ enable_dbg_and_irq
mov x1, x25
mov x2, sp
b do_sp_pc_abort
@@ -475,9 +473,9 @@ el0_undef:
/*
* Undefined instruction
*/
- mov x0, sp
// enable interrupts before calling the main handler
- enable_irq
+ enable_dbg_and_irq
+ mov x0, sp
b do_undefinstr
el0_dbg:
/*
@@ -485,11 +483,13 @@ el0_dbg:
*/
tbnz x24, #0, el0_inv // EL0 only
mrs x0, far_el1
- disable_step x1
mov x1, x25
mov x2, sp
- b do_debug_exception
+ bl do_debug_exception
+ enable_dbg
+ b ret_to_user
el0_inv:
+ enable_dbg
mov x0, sp
mov x1, #BAD_SYNC
mrs x2, esr_el1
@@ -500,15 +500,12 @@ ENDPROC(el0_sync)
el0_irq:
kernel_entry 0
el0_irq_naked:
- disable_step x1
- isb
enable_dbg
#ifdef CONFIG_TRACE_IRQFLAGS
bl trace_hardirqs_off
#endif
irq_handler
- get_thread_info tsk
#ifdef CONFIG_TRACE_IRQFLAGS
bl trace_hardirqs_on
@@ -517,14 +514,6 @@ el0_irq_naked:
ENDPROC(el0_irq)
/*
- * This is the return code to user mode for abort handlers
- */
-ret_from_exception:
- get_thread_info tsk
- b ret_to_user
-ENDPROC(ret_from_exception)
-
-/*
* Register switch for AArch64. The callee-saved registers need to be saved
* and restored. On entry:
* x0 = previous task_struct (must be preserved across the switch)
@@ -563,10 +552,7 @@ ret_fast_syscall:
ldr x1, [tsk, #TI_FLAGS]
and x2, x1, #_TIF_WORK_MASK
cbnz x2, fast_work_pending
- tbz x1, #TIF_SINGLESTEP, fast_exit
- disable_dbg
- enable_step x2
-fast_exit:
+ enable_step_tsk x1, x2
kernel_exit 0, ret = 1
/*
@@ -576,7 +562,7 @@ fast_work_pending:
str x0, [sp, #S_X0] // returned x0
work_pending:
tbnz x1, #TIF_NEED_RESCHED, work_resched
- /* TIF_SIGPENDING or TIF_NOTIFY_RESUME case */
+ /* TIF_SIGPENDING, TIF_NOTIFY_RESUME or TIF_FOREIGN_FPSTATE case */
ldr x2, [sp, #S_PSTATE]
mov x0, sp // 'regs'
tst x2, #PSR_MODE_MASK // user mode regs?
@@ -585,7 +571,6 @@ work_pending:
bl do_notify_resume
b ret_to_user
work_resched:
- enable_dbg
bl schedule
/*
@@ -596,9 +581,7 @@ ret_to_user:
ldr x1, [tsk, #TI_FLAGS]
and x2, x1, #_TIF_WORK_MASK
cbnz x2, work_pending
- tbz x1, #TIF_SINGLESTEP, no_work_pending
- disable_dbg
- enable_step x2
+ enable_step_tsk x1, x2
no_work_pending:
kernel_exit 0, ret = 0
ENDPROC(ret_to_user)
@@ -625,14 +608,11 @@ el0_svc:
mov sc_nr, #__NR_syscalls
el0_svc_naked: // compat entry point
stp x0, scno, [sp, #S_ORIG_X0] // save the original x0 and syscall number
- disable_step x16
- isb
- enable_dbg
- enable_irq
+ enable_dbg_and_irq
- get_thread_info tsk
- ldr x16, [tsk, #TI_FLAGS] // check for syscall tracing
- tbnz x16, #TIF_SYSCALL_TRACE, __sys_trace // are we tracing syscalls?
+ ldr x16, [tsk, #TI_FLAGS] // check for syscall hooks
+ tst x16, #_TIF_SYSCALL_WORK
+ b.ne __sys_trace
adr lr, ret_fast_syscall // return address
cmp scno, sc_nr // check upper syscall limit
b.hs ni_sys
@@ -648,9 +628,8 @@ ENDPROC(el0_svc)
* switches, and waiting for our parent to respond.
*/
__sys_trace:
- mov x1, sp
- mov w0, #0 // trace entry
- bl syscall_trace
+ mov x0, sp
+ bl syscall_trace_enter
adr lr, __sys_trace_return // return address
uxtw scno, w0 // syscall number (possibly new)
mov x1, sp // pointer to regs
@@ -665,9 +644,8 @@ __sys_trace:
__sys_trace_return:
str x0, [sp] // save returned x0
- mov x1, sp
- mov w0, #1 // trace exit
- bl syscall_trace
+ mov x0, sp
+ bl syscall_trace_exit
b ret_to_user
/*
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 4aef42a..ad8aebb 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -35,6 +35,60 @@
#define FPEXC_IDF (1 << 7)
/*
+ * In order to reduce the number of times the FPSIMD state is needlessly saved
+ * and restored, we need to keep track of two things:
+ * (a) for each task, we need to remember which CPU was the last one to have
+ * the task's FPSIMD state loaded into its FPSIMD registers;
+ * (b) for each CPU, we need to remember which task's userland FPSIMD state has
+ * been loaded into its FPSIMD registers most recently, or whether it has
+ * been used to perform kernel mode NEON in the meantime.
+ *
+ * For (a), we add a 'cpu' field to struct fpsimd_state, which gets updated to
+ * the id of the current CPU everytime the state is loaded onto a CPU. For (b),
+ * we add the per-cpu variable 'fpsimd_last_state' (below), which contains the
+ * address of the userland FPSIMD state of the task that was loaded onto the CPU
+ * the most recently, or NULL if kernel mode NEON has been performed after that.
+ *
+ * With this in place, we no longer have to restore the next FPSIMD state right
+ * when switching between tasks. Instead, we can defer this check to userland
+ * resume, at which time we verify whether the CPU's fpsimd_last_state and the
+ * task's fpsimd_state.cpu are still mutually in sync. If this is the case, we
+ * can omit the FPSIMD restore.
+ *
+ * As an optimization, we use the thread_info flag TIF_FOREIGN_FPSTATE to
+ * indicate whether or not the userland FPSIMD state of the current task is
+ * present in the registers. The flag is set unless the FPSIMD registers of this
+ * CPU currently contain the most recent userland FPSIMD state of the current
+ * task.
+ *
+ * For a certain task, the sequence may look something like this:
+ * - the task gets scheduled in; if both the task's fpsimd_state.cpu field
+ * contains the id of the current CPU, and the CPU's fpsimd_last_state per-cpu
+ * variable points to the task's fpsimd_state, the TIF_FOREIGN_FPSTATE flag is
+ * cleared, otherwise it is set;
+ *
+ * - the task returns to userland; if TIF_FOREIGN_FPSTATE is set, the task's
+ * userland FPSIMD state is copied from memory to the registers, the task's
+ * fpsimd_state.cpu field is set to the id of the current CPU, the current
+ * CPU's fpsimd_last_state pointer is set to this task's fpsimd_state and the
+ * TIF_FOREIGN_FPSTATE flag is cleared;
+ *
+ * - the task executes an ordinary syscall; upon return to userland, the
+ * TIF_FOREIGN_FPSTATE flag will still be cleared, so no FPSIMD state is
+ * restored;
+ *
+ * - the task executes a syscall which executes some NEON instructions; this is
+ * preceded by a call to kernel_neon_begin(), which copies the task's FPSIMD
+ * register contents to memory, clears the fpsimd_last_state per-cpu variable
+ * and sets the TIF_FOREIGN_FPSTATE flag;
+ *
+ * - the task gets preempted after kernel_neon_end() is called; as we have not
+ * returned from the 2nd syscall yet, TIF_FOREIGN_FPSTATE is still set so
+ * whatever is in the FPSIMD registers is not saved to memory, but discarded.
+ */
+static DEFINE_PER_CPU(struct fpsimd_state *, fpsimd_last_state);
+
+/*
* Trapped FP/ASIMD access.
*/
void do_fpsimd_acc(unsigned int esr, struct pt_regs *regs)
@@ -72,43 +126,137 @@ void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs)
void fpsimd_thread_switch(struct task_struct *next)
{
- /* check if not kernel threads */
- if (current->mm)
+ /*
+ * Save the current FPSIMD state to memory, but only if whatever is in
+ * the registers is in fact the most recent userland FPSIMD state of
+ * 'current'.
+ */
+ if (current->mm && !test_thread_flag(TIF_FOREIGN_FPSTATE))
fpsimd_save_state(&current->thread.fpsimd_state);
- if (next->mm)
- fpsimd_load_state(&next->thread.fpsimd_state);
+
+ if (next->mm) {
+ /*
+ * If we are switching to a task whose most recent userland
+ * FPSIMD state is already in the registers of *this* cpu,
+ * we can skip loading the state from memory. Otherwise, set
+ * the TIF_FOREIGN_FPSTATE flag so the state will be loaded
+ * upon the next return to userland.
+ */
+ struct fpsimd_state *st = &next->thread.fpsimd_state;
+
+ if (__this_cpu_read(fpsimd_last_state) == st
+ && st->cpu == smp_processor_id())
+ clear_ti_thread_flag(task_thread_info(next),
+ TIF_FOREIGN_FPSTATE);
+ else
+ set_ti_thread_flag(task_thread_info(next),
+ TIF_FOREIGN_FPSTATE);
+ }
}
void fpsimd_flush_thread(void)
{
- preempt_disable();
memset(&current->thread.fpsimd_state, 0, sizeof(struct fpsimd_state));
- fpsimd_load_state(&current->thread.fpsimd_state);
+ set_thread_flag(TIF_FOREIGN_FPSTATE);
+}
+
+/*
+ * Save the userland FPSIMD state of 'current' to memory, but only if the state
+ * currently held in the registers does in fact belong to 'current'
+ */
+void fpsimd_preserve_current_state(void)
+{
+ preempt_disable();
+ if (!test_thread_flag(TIF_FOREIGN_FPSTATE))
+ fpsimd_save_state(&current->thread.fpsimd_state);
+ preempt_enable();
+}
+
+/*
+ * Load the userland FPSIMD state of 'current' from memory, but only if the
+ * FPSIMD state already held in the registers is /not/ the most recent FPSIMD
+ * state of 'current'
+ */
+void fpsimd_restore_current_state(void)
+{
+ preempt_disable();
+ if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) {
+ struct fpsimd_state *st = &current->thread.fpsimd_state;
+
+ fpsimd_load_state(st);
+ this_cpu_write(fpsimd_last_state, st);
+ st->cpu = smp_processor_id();
+ }
+ preempt_enable();
+}
+
+/*
+ * Load an updated userland FPSIMD state for 'current' from memory and set the
+ * flag that indicates that the FPSIMD register contents are the most recent
+ * FPSIMD state of 'current'
+ */
+void fpsimd_update_current_state(struct fpsimd_state *state)
+{
+ preempt_disable();
+ fpsimd_load_state(state);
+ if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) {
+ struct fpsimd_state *st = &current->thread.fpsimd_state;
+
+ this_cpu_write(fpsimd_last_state, st);
+ st->cpu = smp_processor_id();
+ }
preempt_enable();
}
+/*
+ * Invalidate live CPU copies of task t's FPSIMD state
+ */
+void fpsimd_flush_task_state(struct task_struct *t)
+{
+ t->thread.fpsimd_state.cpu = NR_CPUS;
+}
+
#ifdef CONFIG_KERNEL_MODE_NEON
+static DEFINE_PER_CPU(struct fpsimd_partial_state, hardirq_fpsimdstate);
+static DEFINE_PER_CPU(struct fpsimd_partial_state, softirq_fpsimdstate);
+
/*
* Kernel-side NEON support functions
*/
-void kernel_neon_begin(void)
+void kernel_neon_begin_partial(u32 num_regs)
{
- /* Avoid using the NEON in interrupt context */
- BUG_ON(in_interrupt());
- preempt_disable();
+ if (in_interrupt()) {
+ struct fpsimd_partial_state *s = this_cpu_ptr(
+ in_irq() ? &hardirq_fpsimdstate : &softirq_fpsimdstate);
- if (current->mm)
- fpsimd_save_state(&current->thread.fpsimd_state);
+ BUG_ON(num_regs > 32);
+ fpsimd_save_partial_state(s, roundup(num_regs, 2));
+ } else {
+ /*
+ * Save the userland FPSIMD state if we have one and if we
+ * haven't done so already. Clear fpsimd_last_state to indicate
+ * that there is no longer userland FPSIMD state in the
+ * registers.
+ */
+ preempt_disable();
+ if (current->mm &&
+ !test_and_set_thread_flag(TIF_FOREIGN_FPSTATE))
+ fpsimd_save_state(&current->thread.fpsimd_state);
+ this_cpu_write(fpsimd_last_state, NULL);
+ }
}
-EXPORT_SYMBOL(kernel_neon_begin);
+EXPORT_SYMBOL(kernel_neon_begin_partial);
void kernel_neon_end(void)
{
- if (current->mm)
- fpsimd_load_state(&current->thread.fpsimd_state);
-
- preempt_enable();
+ if (in_interrupt()) {
+ struct fpsimd_partial_state *s = this_cpu_ptr(
+ in_irq() ? &hardirq_fpsimdstate : &softirq_fpsimdstate);
+ fpsimd_load_partial_state(s);
+ } else {
+ preempt_enable();
+ }
}
EXPORT_SYMBOL(kernel_neon_end);
@@ -120,12 +268,12 @@ static int fpsimd_cpu_pm_notifier(struct notifier_block *self,
{
switch (cmd) {
case CPU_PM_ENTER:
- if (current->mm)
+ if (current->mm && !test_thread_flag(TIF_FOREIGN_FPSTATE))
fpsimd_save_state(&current->thread.fpsimd_state);
break;
case CPU_PM_EXIT:
if (current->mm)
- fpsimd_load_state(&current->thread.fpsimd_state);
+ set_thread_flag(TIF_FOREIGN_FPSTATE);
break;
case CPU_PM_ENTER_FAILED:
default:
diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
new file mode 100644
index 0000000..7924d73
--- /dev/null
+++ b/arch/arm64/kernel/ftrace.c
@@ -0,0 +1,176 @@
+/*
+ * arch/arm64/kernel/ftrace.c
+ *
+ * Copyright (C) 2013 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/ftrace.h>
+#include <linux/swab.h>
+#include <linux/uaccess.h>
+
+#include <asm/cacheflush.h>
+#include <asm/ftrace.h>
+#include <asm/insn.h>
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+/*
+ * Replace a single instruction, which may be a branch or NOP.
+ * If @validate == true, a replaced instruction is checked against 'old'.
+ */
+static int ftrace_modify_code(unsigned long pc, u32 old, u32 new,
+ bool validate)
+{
+ u32 replaced;
+
+ /*
+ * Note:
+ * Due to modules and __init, code can disappear and change,
+ * we need to protect against faulting as well as code changing.
+ * We do this by aarch64_insn_*() which use the probe_kernel_*().
+ *
+ * No lock is held here because all the modifications are run
+ * through stop_machine().
+ */
+ if (validate) {
+ if (aarch64_insn_read((void *)pc, &replaced))
+ return -EFAULT;
+
+ if (replaced != old)
+ return -EINVAL;
+ }
+ if (aarch64_insn_patch_text_nosync((void *)pc, new))
+ return -EPERM;
+
+ return 0;
+}
+
+/*
+ * Replace tracer function in ftrace_caller()
+ */
+int ftrace_update_ftrace_func(ftrace_func_t func)
+{
+ unsigned long pc;
+ u32 new;
+
+ pc = (unsigned long)&ftrace_call;
+ new = aarch64_insn_gen_branch_imm(pc, (unsigned long)func, true);
+
+ return ftrace_modify_code(pc, 0, new, false);
+}
+
+/*
+ * Turn on the call to ftrace_caller() in instrumented function
+ */
+int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
+{
+ unsigned long pc = rec->ip;
+ u32 old, new;
+
+ old = aarch64_insn_gen_nop();
+ new = aarch64_insn_gen_branch_imm(pc, addr, true);
+
+ return ftrace_modify_code(pc, old, new, true);
+}
+
+/*
+ * Turn off the call to ftrace_caller() in instrumented function
+ */
+int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
+ unsigned long addr)
+{
+ unsigned long pc = rec->ip;
+ u32 old, new;
+
+ old = aarch64_insn_gen_branch_imm(pc, addr, true);
+ new = aarch64_insn_gen_nop();
+
+ return ftrace_modify_code(pc, old, new, true);
+}
+
+int __init ftrace_dyn_arch_init(void)
+{
+ return 0;
+}
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+/*
+ * function_graph tracer expects ftrace_return_to_handler() to be called
+ * on the way back to parent. For this purpose, this function is called
+ * in _mcount() or ftrace_caller() to replace return address (*parent) on
+ * the call stack to return_to_handler.
+ *
+ * Note that @frame_pointer is used only for sanity check later.
+ */
+void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
+ unsigned long frame_pointer)
+{
+ unsigned long return_hooker = (unsigned long)&return_to_handler;
+ unsigned long old;
+ struct ftrace_graph_ent trace;
+ int err;
+
+ if (unlikely(atomic_read(&current->tracing_graph_pause)))
+ return;
+
+ /*
+ * Note:
+ * No protection against faulting at *parent, which may be seen
+ * on other archs. It's unlikely on AArch64.
+ */
+ old = *parent;
+ *parent = return_hooker;
+
+ trace.func = self_addr;
+ trace.depth = current->curr_ret_stack + 1;
+
+ /* Only trace if the calling function expects to */
+ if (!ftrace_graph_entry(&trace)) {
+ *parent = old;
+ return;
+ }
+
+ err = ftrace_push_return_trace(old, self_addr, &trace.depth,
+ frame_pointer);
+ if (err == -EBUSY) {
+ *parent = old;
+ return;
+ }
+}
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+/*
+ * Turn on/off the call to ftrace_graph_caller() in ftrace_caller()
+ * depending on @enable.
+ */
+static int ftrace_modify_graph_caller(bool enable)
+{
+ unsigned long pc = (unsigned long)&ftrace_graph_call;
+ u32 branch, nop;
+
+ branch = aarch64_insn_gen_branch_imm(pc,
+ (unsigned long)ftrace_graph_caller, false);
+ nop = aarch64_insn_gen_nop();
+
+ if (enable)
+ return ftrace_modify_code(pc, nop, branch, true);
+ else
+ return ftrace_modify_code(pc, branch, nop, true);
+}
+
+int ftrace_enable_ftrace_graph_caller(void)
+{
+ return ftrace_modify_graph_caller(true);
+}
+
+int ftrace_disable_ftrace_graph_caller(void)
+{
+ return ftrace_modify_graph_caller(false);
+}
+#endif /* CONFIG_DYNAMIC_FTRACE */
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 738291b..a96d3a6 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -342,11 +342,9 @@ ENTRY(set_cpu_boot_mode_flag)
cmp w20, #BOOT_CPU_MODE_EL2
b.ne 1f
add x1, x1, #4
-1: dc cvac, x1 // Clean potentially dirty cache line
- dsb sy
- str w20, [x1] // This CPU has booted in EL1
- dc civac, x1 // Clean&invalidate potentially stale cache line
- dsb sy
+1: str w20, [x1] // This CPU has booted in EL1
+ dmb sy
+ dc ivac, x1 // Invalidate potentially stale cache line
ret
ENDPROC(set_cpu_boot_mode_flag)
diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
index bee7897..df1cf15 100644
--- a/arch/arm64/kernel/hw_breakpoint.c
+++ b/arch/arm64/kernel/hw_breakpoint.c
@@ -20,6 +20,7 @@
#define pr_fmt(fmt) "hw-breakpoint: " fmt
+#include <linux/compat.h>
#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/hw_breakpoint.h>
@@ -27,7 +28,6 @@
#include <linux/ptrace.h>
#include <linux/smp.h>
-#include <asm/compat.h>
#include <asm/current.h>
#include <asm/debug-monitors.h>
#include <asm/hw_breakpoint.h>
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index 6391485..43b7c34 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -20,6 +20,7 @@
#include <stdarg.h>
+#include <linux/compat.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/kernel.h>
@@ -113,32 +114,62 @@ void arch_cpu_idle_dead(void)
}
#endif
+/*
+ * Called by kexec, immediately prior to machine_kexec().
+ *
+ * This must completely disable all secondary CPUs; simply causing those CPUs
+ * to execute e.g. a RAM-based pin loop is not sufficient. This allows the
+ * kexec'd kernel to use any and all RAM as it sees fit, without having to
+ * avoid any code or data used by any SW CPU pin loop. The CPU hotplug
+ * functionality embodied in disable_nonboot_cpus() to achieve this.
+ */
void machine_shutdown(void)
{
-#ifdef CONFIG_SMP
- smp_send_stop();
-#endif
+ disable_nonboot_cpus();
}
+/*
+ * Halting simply requires that the secondary CPUs stop performing any
+ * activity (executing tasks, handling interrupts). smp_send_stop()
+ * achieves this.
+ */
void machine_halt(void)
{
- machine_shutdown();
+ local_irq_disable();
+ smp_send_stop();
while (1);
}
+/*
+ * Power-off simply requires that the secondary CPUs stop performing any
+ * activity (executing tasks, handling interrupts). smp_send_stop()
+ * achieves this. When the system power is turned off, it will take all CPUs
+ * with it.
+ */
void machine_power_off(void)
{
- machine_shutdown();
+ local_irq_disable();
+ smp_send_stop();
if (pm_power_off)
pm_power_off();
}
+/*
+ * Restart requires that the secondary CPUs stop performing any activity
+ * while the primary CPU resets the system. Systems with a single CPU can
+ * use soft_restart() as their machine descriptor's .restart hook, since that
+ * will cause the only available CPU to reset. Systems with multiple CPUs must
+ * provide a HW restart implementation, to ensure that all CPUs reset at once.
+ * This is required so that any code running after reset on the primary CPU
+ * doesn't have to co-ordinate with other CPUs to ensure they aren't still
+ * executing pre-reset code, and using RAM that the primary CPU's code wishes
+ * to use. Implementing such co-ordination would be essentially impossible.
+ */
void machine_restart(char *cmd)
{
- machine_shutdown();
-
/* Disable interrupts first */
local_irq_disable();
+ smp_send_stop();
/* Now call the architecture specific reboot code. */
if (arm_pm_restart)
@@ -205,7 +236,7 @@ void release_thread(struct task_struct *dead_task)
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
- fpsimd_save_state(&current->thread.fpsimd_state);
+ fpsimd_preserve_current_state();
*dst = *src;
return 0;
}
@@ -300,7 +331,7 @@ struct task_struct *__switch_to(struct task_struct *prev,
* Complete any pending TLB or cache maintenance on this CPU in case
* the thread migrates to a different CPU.
*/
- dsb();
+ dsb(ish);
/* the actual thread switch */
last = cpu_switch_to(prev, next);
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 6a8928b..3e926b9 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -19,6 +19,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/compat.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
@@ -41,6 +42,9 @@
#include <asm/traps.h>
#include <asm/system_misc.h>
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
/*
* TODO: does not yet catch signals sent when the child dies.
* in exit.c or in signal.c.
@@ -517,6 +521,7 @@ static int fpr_set(struct task_struct *target, const struct user_regset *regset,
return ret;
target->thread.fpsimd_state.user_fpsimd = newstate;
+ fpsimd_flush_task_state(target);
return ret;
}
@@ -764,6 +769,7 @@ static int compat_vfp_set(struct task_struct *target,
uregs->fpcr = fpscr & VFP_FPSCR_CTRL_MASK;
}
+ fpsimd_flush_task_state(target);
return ret;
}
@@ -1058,35 +1064,49 @@ long arch_ptrace(struct task_struct *child, long request,
return ptrace_request(child, request, addr, data);
}
-asmlinkage int syscall_trace(int dir, struct pt_regs *regs)
+enum ptrace_syscall_dir {
+ PTRACE_SYSCALL_ENTER = 0,
+ PTRACE_SYSCALL_EXIT,
+};
+
+static void tracehook_report_syscall(struct pt_regs *regs,
+ enum ptrace_syscall_dir dir)
{
+ int regno;
unsigned long saved_reg;
- if (!test_thread_flag(TIF_SYSCALL_TRACE))
- return regs->syscallno;
-
- if (is_compat_task()) {
- /* AArch32 uses ip (r12) for scratch */
- saved_reg = regs->regs[12];
- regs->regs[12] = dir;
- } else {
- /*
- * Save X7. X7 is used to denote syscall entry/exit:
- * X7 = 0 -> entry, = 1 -> exit
- */
- saved_reg = regs->regs[7];
- regs->regs[7] = dir;
- }
+ /*
+ * A scratch register (ip(r12) on AArch32, x7 on AArch64) is
+ * used to denote syscall entry/exit:
+ */
+ regno = (is_compat_task() ? 12 : 7);
+ saved_reg = regs->regs[regno];
+ regs->regs[regno] = dir;
- if (dir)
+ if (dir == PTRACE_SYSCALL_EXIT)
tracehook_report_syscall_exit(regs, 0);
else if (tracehook_report_syscall_entry(regs))
regs->syscallno = ~0UL;
- if (is_compat_task())
- regs->regs[12] = saved_reg;
- else
- regs->regs[7] = saved_reg;
+ regs->regs[regno] = saved_reg;
+}
+
+asmlinkage int syscall_trace_enter(struct pt_regs *regs)
+{
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_ENTER);
+
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, regs->syscallno);
return regs->syscallno;
}
+
+asmlinkage void syscall_trace_exit(struct pt_regs *regs)
+{
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_exit(regs, regs_return_value(regs));
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall(regs, PTRACE_SYSCALL_EXIT);
+}
diff --git a/arch/arm64/kernel/return_address.c b/arch/arm64/kernel/return_address.c
new file mode 100644
index 0000000..89102a6
--- /dev/null
+++ b/arch/arm64/kernel/return_address.c
@@ -0,0 +1,55 @@
+/*
+ * arch/arm64/kernel/return_address.c
+ *
+ * Copyright (C) 2013 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/export.h>
+#include <linux/ftrace.h>
+
+#include <asm/stacktrace.h>
+
+struct return_address_data {
+ unsigned int level;
+ void *addr;
+};
+
+static int save_return_addr(struct stackframe *frame, void *d)
+{
+ struct return_address_data *data = d;
+
+ if (!data->level) {
+ data->addr = (void *)frame->pc;
+ return 1;
+ } else {
+ --data->level;
+ return 0;
+ }
+}
+
+void *return_address(unsigned int level)
+{
+ struct return_address_data data;
+ struct stackframe frame;
+ register unsigned long current_sp asm ("sp");
+
+ data.level = level + 2;
+ data.addr = NULL;
+
+ frame.fp = (unsigned long)__builtin_frame_address(0);
+ frame.sp = current_sp;
+ frame.pc = (unsigned long)return_address; /* dummy */
+
+ walk_stackframe(&frame, save_return_addr, &data);
+
+ if (!data.level)
+ return data.addr;
+ else
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(return_address);
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index e578171..46d1125 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -25,6 +25,7 @@
#include <linux/utsname.h>
#include <linux/initrd.h>
#include <linux/console.h>
+#include <linux/cache.h>
#include <linux/bootmem.h>
#include <linux/seq_file.h>
#include <linux/screen_info.h>
@@ -200,6 +201,8 @@ static void __init setup_processor(void)
{
struct cpu_info *cpu_info;
u64 features, block;
+ u32 cwg;
+ int cls;
cpu_info = lookup_processor_type(read_cpuid_id());
if (!cpu_info) {
@@ -217,6 +220,18 @@ static void __init setup_processor(void)
elf_hwcap = 0;
/*
+ * Check for sane CTR_EL0.CWG value.
+ */
+ cwg = cache_type_cwg();
+ cls = cache_line_size();
+ if (!cwg)
+ pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
+ cls);
+ if (L1_CACHE_BYTES < cls)
+ pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
+ L1_CACHE_BYTES, cls);
+
+ /*
* ID_AA64ISAR0_EL1 contains 4-bit wide signed feature blocks.
* The blocks we test below represent incremental functionality
* for non-negative values. Negative values are reserved.
@@ -363,7 +378,6 @@ void __init setup_arch(char **cmdline_p)
*cmdline_p = boot_command_line;
- init_mem_pgprot();
early_ioremap_init();
parse_early_param();
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 890a591..6357b9c 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -17,6 +17,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/compat.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/personality.h>
@@ -25,7 +26,6 @@
#include <linux/tracehook.h>
#include <linux/ratelimit.h>
-#include <asm/compat.h>
#include <asm/debug-monitors.h>
#include <asm/elf.h>
#include <asm/cacheflush.h>
@@ -51,7 +51,7 @@ static int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
int err;
/* dump the hardware registers to the fpsimd_state structure */
- fpsimd_save_state(fpsimd);
+ fpsimd_preserve_current_state();
/* copy the FP and status/control registers */
err = __copy_to_user(ctx->vregs, fpsimd->vregs, sizeof(fpsimd->vregs));
@@ -86,11 +86,8 @@ static int restore_fpsimd_context(struct fpsimd_context __user *ctx)
__get_user_error(fpsimd.fpcr, &ctx->fpcr, err);
/* load the hardware registers from the fpsimd_state structure */
- if (!err) {
- preempt_disable();
- fpsimd_load_state(&fpsimd);
- preempt_enable();
- }
+ if (!err)
+ fpsimd_update_current_state(&fpsimd);
return err ? -EFAULT : 0;
}
@@ -100,8 +97,7 @@ static int restore_sigframe(struct pt_regs *regs,
{
sigset_t set;
int i, err;
- struct aux_context __user *aux =
- (struct aux_context __user *)sf->uc.uc_mcontext.__reserved;
+ void *aux = sf->uc.uc_mcontext.__reserved;
err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
if (err == 0)
@@ -121,8 +117,11 @@ static int restore_sigframe(struct pt_regs *regs,
err |= !valid_user_regs(&regs->user_regs);
- if (err == 0)
- err |= restore_fpsimd_context(&aux->fpsimd);
+ if (err == 0) {
+ struct fpsimd_context *fpsimd_ctx =
+ container_of(aux, struct fpsimd_context, head);
+ err |= restore_fpsimd_context(fpsimd_ctx);
+ }
return err;
}
@@ -167,8 +166,8 @@ static int setup_sigframe(struct rt_sigframe __user *sf,
struct pt_regs *regs, sigset_t *set)
{
int i, err = 0;
- struct aux_context __user *aux =
- (struct aux_context __user *)sf->uc.uc_mcontext.__reserved;
+ void *aux = sf->uc.uc_mcontext.__reserved;
+ struct _aarch64_ctx *end;
/* set up the stack frame for unwinding */
__put_user_error(regs->regs[29], &sf->fp, err);
@@ -185,12 +184,27 @@ static int setup_sigframe(struct rt_sigframe __user *sf,
err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
- if (err == 0)
- err |= preserve_fpsimd_context(&aux->fpsimd);
+ if (err == 0) {
+ struct fpsimd_context *fpsimd_ctx =
+ container_of(aux, struct fpsimd_context, head);
+ err |= preserve_fpsimd_context(fpsimd_ctx);
+ aux += sizeof(*fpsimd_ctx);
+ }
+
+ /* fault information, if valid */
+ if (current->thread.fault_code) {
+ struct esr_context *esr_ctx =
+ container_of(aux, struct esr_context, head);
+ __put_user_error(ESR_MAGIC, &esr_ctx->head.magic, err);
+ __put_user_error(sizeof(*esr_ctx), &esr_ctx->head.size, err);
+ __put_user_error(current->thread.fault_code, &esr_ctx->esr, err);
+ aux += sizeof(*esr_ctx);
+ }
/* set the "end" magic */
- __put_user_error(0, &aux->end.magic, err);
- __put_user_error(0, &aux->end.size, err);
+ end = aux;
+ __put_user_error(0, &end->magic, err);
+ __put_user_error(0, &end->size, err);
return err;
}
@@ -416,4 +430,8 @@ asmlinkage void do_notify_resume(struct pt_regs *regs,
clear_thread_flag(TIF_NOTIFY_RESUME);
tracehook_notify_resume(regs);
}
+
+ if (thread_flags & _TIF_FOREIGN_FPSTATE)
+ fpsimd_restore_current_state();
+
}
diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c
index b3fc9f5..3491c63 100644
--- a/arch/arm64/kernel/signal32.c
+++ b/arch/arm64/kernel/signal32.c
@@ -23,6 +23,7 @@
#include <linux/syscalls.h>
#include <linux/ratelimit.h>
+#include <asm/esr.h>
#include <asm/fpsimd.h>
#include <asm/signal32.h>
#include <asm/uaccess.h>
@@ -81,6 +82,8 @@ struct compat_vfp_sigframe {
#define VFP_MAGIC 0x56465001
#define VFP_STORAGE_SIZE sizeof(struct compat_vfp_sigframe)
+#define FSR_WRITE_SHIFT (11)
+
struct compat_aux_sigframe {
struct compat_vfp_sigframe vfp;
@@ -219,7 +222,7 @@ static int compat_preserve_vfp_context(struct compat_vfp_sigframe __user *frame)
* Note that this also saves V16-31, which aren't visible
* in AArch32.
*/
- fpsimd_save_state(fpsimd);
+ fpsimd_preserve_current_state();
/* Place structure header on the stack */
__put_user_error(magic, &frame->magic, err);
@@ -282,11 +285,8 @@ static int compat_restore_vfp_context(struct compat_vfp_sigframe __user *frame)
* We don't need to touch the exception register, so
* reload the hardware state.
*/
- if (!err) {
- preempt_disable();
- fpsimd_load_state(&fpsimd);
- preempt_enable();
- }
+ if (!err)
+ fpsimd_update_current_state(&fpsimd);
return err ? -EFAULT : 0;
}
@@ -500,7 +500,9 @@ static int compat_setup_sigframe(struct compat_sigframe __user *sf,
__put_user_error(regs->pstate, &sf->uc.uc_mcontext.arm_cpsr, err);
__put_user_error((compat_ulong_t)0, &sf->uc.uc_mcontext.trap_no, err);
- __put_user_error((compat_ulong_t)0, &sf->uc.uc_mcontext.error_code, err);
+ /* set the compat FSR WnR */
+ __put_user_error(!!(current->thread.fault_code & ESR_EL1_WRITE) <<
+ FSR_WRITE_SHIFT, &sf->uc.uc_mcontext.error_code, err);
__put_user_error(current->thread.fault_address, &sf->uc.uc_mcontext.fault_address, err);
__put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err);
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index c3cb160..40f38f4 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -35,6 +35,7 @@
#include <linux/clockchips.h>
#include <linux/completion.h>
#include <linux/of.h>
+#include <linux/irq_work.h>
#include <asm/atomic.h>
#include <asm/cacheflush.h>
@@ -62,6 +63,7 @@ enum ipi_msg_type {
IPI_CALL_FUNC_SINGLE,
IPI_CPU_STOP,
IPI_TIMER,
+ IPI_IRQ_WORK,
};
/*
@@ -477,6 +479,14 @@ void arch_send_call_function_single_ipi(int cpu)
smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
}
+#ifdef CONFIG_IRQ_WORK
+void arch_irq_work_raise(void)
+{
+ if (smp_cross_call)
+ smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK);
+}
+#endif
+
static const char *ipi_types[NR_IPI] = {
#define S(x,s) [x - IPI_RESCHEDULE] = s
S(IPI_RESCHEDULE, "Rescheduling interrupts"),
@@ -484,6 +494,7 @@ static const char *ipi_types[NR_IPI] = {
S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"),
S(IPI_CPU_STOP, "CPU stop interrupts"),
S(IPI_TIMER, "Timer broadcast interrupts"),
+ S(IPI_IRQ_WORK, "IRQ work interrupts"),
};
void show_ipi_list(struct seq_file *p, int prec)
@@ -576,6 +587,14 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
break;
#endif
+#ifdef CONFIG_IRQ_WORK
+ case IPI_IRQ_WORK:
+ irq_enter();
+ irq_work_run();
+ irq_exit();
+ break;
+#endif
+
default:
pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);
break;
diff --git a/arch/arm64/kernel/smp_spin_table.c b/arch/arm64/kernel/smp_spin_table.c
index 7a530d2..0347d38 100644
--- a/arch/arm64/kernel/smp_spin_table.c
+++ b/arch/arm64/kernel/smp_spin_table.c
@@ -30,7 +30,6 @@ extern void secondary_holding_pen(void);
volatile unsigned long secondary_holding_pen_release = INVALID_HWID;
static phys_addr_t cpu_release_addr[NR_CPUS];
-static DEFINE_RAW_SPINLOCK(boot_lock);
/*
* Write secondary_holding_pen_release in a way that is guaranteed to be
@@ -94,14 +93,6 @@ static int smp_spin_table_cpu_prepare(unsigned int cpu)
static int smp_spin_table_cpu_boot(unsigned int cpu)
{
- unsigned long timeout;
-
- /*
- * Set synchronisation state between this boot processor
- * and the secondary one
- */
- raw_spin_lock(&boot_lock);
-
/*
* Update the pen release flag.
*/
@@ -112,34 +103,7 @@ static int smp_spin_table_cpu_boot(unsigned int cpu)
*/
sev();
- timeout = jiffies + (1 * HZ);
- while (time_before(jiffies, timeout)) {
- if (secondary_holding_pen_release == INVALID_HWID)
- break;
- udelay(10);
- }
-
- /*
- * Now the secondary core is starting up let it run its
- * calibrations, then wait for it to finish
- */
- raw_spin_unlock(&boot_lock);
-
- return secondary_holding_pen_release != INVALID_HWID ? -ENOSYS : 0;
-}
-
-static void smp_spin_table_cpu_postboot(void)
-{
- /*
- * Let the primary processor know we're out of the pen.
- */
- write_pen_release(INVALID_HWID);
-
- /*
- * Synchronise with the boot thread.
- */
- raw_spin_lock(&boot_lock);
- raw_spin_unlock(&boot_lock);
+ return 0;
}
const struct cpu_operations smp_spin_table_ops = {
@@ -147,5 +111,4 @@ const struct cpu_operations smp_spin_table_ops = {
.cpu_init = smp_spin_table_cpu_init,
.cpu_prepare = smp_spin_table_cpu_prepare,
.cpu_boot = smp_spin_table_cpu_boot,
- .cpu_postboot = smp_spin_table_cpu_postboot,
};
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index 38f0558..55437ba 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -35,7 +35,7 @@
* ldp x29, x30, [sp]
* add sp, sp, #0x10
*/
-int unwind_frame(struct stackframe *frame)
+int notrace unwind_frame(struct stackframe *frame)
{
unsigned long high, low;
unsigned long fp = frame->fp;
diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c
index 6815987..1a7125c 100644
--- a/arch/arm64/kernel/time.c
+++ b/arch/arm64/kernel/time.c
@@ -18,6 +18,7 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/clockchips.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
@@ -69,6 +70,8 @@ void __init time_init(void)
of_clk_init(NULL);
clocksource_of_init();
+ tick_setup_hrtimer_broadcast();
+
arch_timer_rate = arch_timer_get_rate();
if (!arch_timer_rate)
panic("Unable to initialise architected timer.\n");
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
index 3e06b0b..43514f9 100644
--- a/arch/arm64/kernel/topology.c
+++ b/arch/arm64/kernel/topology.c
@@ -17,10 +17,192 @@
#include <linux/percpu.h>
#include <linux/node.h>
#include <linux/nodemask.h>
+#include <linux/of.h>
#include <linux/sched.h>
#include <asm/topology.h>
+static int __init get_cpu_for_node(struct device_node *node)
+{
+ struct device_node *cpu_node;
+ int cpu;
+
+ cpu_node = of_parse_phandle(node, "cpu", 0);
+ if (!cpu_node)
+ return -1;
+
+ for_each_possible_cpu(cpu) {
+ if (of_get_cpu_node(cpu, NULL) == cpu_node) {
+ of_node_put(cpu_node);
+ return cpu;
+ }
+ }
+
+ pr_crit("Unable to find CPU node for %s\n", cpu_node->full_name);
+
+ of_node_put(cpu_node);
+ return -1;
+}
+
+static int __init parse_core(struct device_node *core, int cluster_id,
+ int core_id)
+{
+ char name[10];
+ bool leaf = true;
+ int i = 0;
+ int cpu;
+ struct device_node *t;
+
+ do {
+ snprintf(name, sizeof(name), "thread%d", i);
+ t = of_get_child_by_name(core, name);
+ if (t) {
+ leaf = false;
+ cpu = get_cpu_for_node(t);
+ if (cpu >= 0) {
+ cpu_topology[cpu].cluster_id = cluster_id;
+ cpu_topology[cpu].core_id = core_id;
+ cpu_topology[cpu].thread_id = i;
+ } else {
+ pr_err("%s: Can't get CPU for thread\n",
+ t->full_name);
+ of_node_put(t);
+ return -EINVAL;
+ }
+ of_node_put(t);
+ }
+ i++;
+ } while (t);
+
+ cpu = get_cpu_for_node(core);
+ if (cpu >= 0) {
+ if (!leaf) {
+ pr_err("%s: Core has both threads and CPU\n",
+ core->full_name);
+ return -EINVAL;
+ }
+
+ cpu_topology[cpu].cluster_id = cluster_id;
+ cpu_topology[cpu].core_id = core_id;
+ } else if (leaf) {
+ pr_err("%s: Can't get CPU for leaf core\n", core->full_name);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __init parse_cluster(struct device_node *cluster, int depth)
+{
+ char name[10];
+ bool leaf = true;
+ bool has_cores = false;
+ struct device_node *c;
+ static int cluster_id __initdata;
+ int core_id = 0;
+ int i, ret;
+
+ /*
+ * First check for child clusters; we currently ignore any
+ * information about the nesting of clusters and present the
+ * scheduler with a flat list of them.
+ */
+ i = 0;
+ do {
+ snprintf(name, sizeof(name), "cluster%d", i);
+ c = of_get_child_by_name(cluster, name);
+ if (c) {
+ leaf = false;
+ ret = parse_cluster(c, depth + 1);
+ of_node_put(c);
+ if (ret != 0)
+ return ret;
+ }
+ i++;
+ } while (c);
+
+ /* Now check for cores */
+ i = 0;
+ do {
+ snprintf(name, sizeof(name), "core%d", i);
+ c = of_get_child_by_name(cluster, name);
+ if (c) {
+ has_cores = true;
+
+ if (depth == 0) {
+ pr_err("%s: cpu-map children should be clusters\n",
+ c->full_name);
+ of_node_put(c);
+ return -EINVAL;
+ }
+
+ if (leaf) {
+ ret = parse_core(c, cluster_id, core_id++);
+ } else {
+ pr_err("%s: Non-leaf cluster with core %s\n",
+ cluster->full_name, name);
+ ret = -EINVAL;
+ }
+
+ of_node_put(c);
+ if (ret != 0)
+ return ret;
+ }
+ i++;
+ } while (c);
+
+ if (leaf && !has_cores)
+ pr_warn("%s: empty cluster\n", cluster->full_name);
+
+ if (leaf)
+ cluster_id++;
+
+ return 0;
+}
+
+static int __init parse_dt_topology(void)
+{
+ struct device_node *cn, *map;
+ int ret = 0;
+ int cpu;
+
+ cn = of_find_node_by_path("/cpus");
+ if (!cn) {
+ pr_err("No CPU information found in DT\n");
+ return 0;
+ }
+
+ /*
+ * When topology is provided cpu-map is essentially a root
+ * cluster with restricted subnodes.
+ */
+ map = of_get_child_by_name(cn, "cpu-map");
+ if (!map)
+ goto out;
+
+ ret = parse_cluster(map, 0);
+ if (ret != 0)
+ goto out_map;
+
+ /*
+ * Check that all cores are in the topology; the SMP code will
+ * only mark cores described in the DT as possible.
+ */
+ for_each_possible_cpu(cpu) {
+ if (cpu_topology[cpu].cluster_id == -1) {
+ pr_err("CPU%d: No topology information specified\n",
+ cpu);
+ ret = -EINVAL;
+ }
+ }
+
+out_map:
+ of_node_put(map);
+out:
+ of_node_put(cn);
+ return ret;
+}
+
/*
* cpu topology table
*/
@@ -39,13 +221,9 @@ static void update_siblings_masks(unsigned int cpuid)
if (cpuid_topo->cluster_id == -1) {
/*
- * DT does not contain topology information for this cpu
- * reset it to default behaviour
+ * DT does not contain topology information for this cpu.
*/
pr_debug("CPU%u: No topology information configured\n", cpuid);
- cpuid_topo->core_id = 0;
- cpumask_set_cpu(cpuid, &cpuid_topo->core_sibling);
- cpumask_set_cpu(cpuid, &cpuid_topo->thread_sibling);
return;
}
@@ -74,22 +252,32 @@ void store_cpu_topology(unsigned int cpuid)
update_siblings_masks(cpuid);
}
-/*
- * init_cpu_topology is called at boot when only one cpu is running
- * which prevent simultaneous write access to cpu_topology array
- */
-void __init init_cpu_topology(void)
+static void __init reset_cpu_topology(void)
{
unsigned int cpu;
- /* init core mask and power*/
for_each_possible_cpu(cpu) {
struct cpu_topology *cpu_topo = &cpu_topology[cpu];
cpu_topo->thread_id = -1;
- cpu_topo->core_id = -1;
+ cpu_topo->core_id = 0;
cpu_topo->cluster_id = -1;
+
cpumask_clear(&cpu_topo->core_sibling);
+ cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
cpumask_clear(&cpu_topo->thread_sibling);
+ cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
}
}
+
+void __init init_cpu_topology(void)
+{
+ reset_cpu_topology();
+
+ /*
+ * Discard anything that was parsed if we hit an error so we
+ * don't use partial information.
+ */
+ if (parse_dt_topology())
+ reset_cpu_topology();
+}
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 7ffaddd..c43cfa9 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -251,10 +251,13 @@ void die(const char *str, struct pt_regs *regs, int err)
void arm64_notify_die(const char *str, struct pt_regs *regs,
struct siginfo *info, int err)
{
- if (user_mode(regs))
+ if (user_mode(regs)) {
+ current->thread.fault_address = 0;
+ current->thread.fault_code = err;
force_sig_info(info->si_signo, info, current);
- else
+ } else {
die(str, regs, err);
+ }
}
asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index 4ba7a55..f1e6d5c 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -13,7 +13,7 @@
#define ARM_EXIT_DISCARD(x) x
OUTPUT_ARCH(aarch64)
-ENTRY(stext)
+ENTRY(_text)
jiffies = jiffies_64;
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