aboutsummaryrefslogtreecommitdiff
path: root/arch/um/kernel
diff options
context:
space:
mode:
Diffstat (limited to 'arch/um/kernel')
-rw-r--r--arch/um/kernel/Makefile2
-rw-r--r--arch/um/kernel/exitcode.c4
-rw-r--r--arch/um/kernel/irq.c4
-rw-r--r--arch/um/kernel/maccess.c24
-rw-r--r--arch/um/kernel/mem.c8
-rw-r--r--arch/um/kernel/process.c15
-rw-r--r--arch/um/kernel/sysrq.c102
-rw-r--r--arch/um/kernel/trap.c36
-rw-r--r--arch/um/kernel/um_arch.c2
9 files changed, 133 insertions, 64 deletions
diff --git a/arch/um/kernel/Makefile b/arch/um/kernel/Makefile
index babe21826e3e..d8b78a03855c 100644
--- a/arch/um/kernel/Makefile
+++ b/arch/um/kernel/Makefile
@@ -13,7 +13,7 @@ clean-files :=
obj-y = config.o exec.o exitcode.o irq.o ksyms.o mem.o \
physmem.o process.o ptrace.o reboot.o sigio.o \
signal.o smp.o syscall.o sysrq.o time.o tlb.o trap.o \
- um_arch.o umid.o skas/
+ um_arch.o umid.o maccess.o skas/
obj-$(CONFIG_BLK_DEV_INITRD) += initrd.o
obj-$(CONFIG_GPROF) += gprof_syms.o
diff --git a/arch/um/kernel/exitcode.c b/arch/um/kernel/exitcode.c
index 829df49dee99..41ebbfebb333 100644
--- a/arch/um/kernel/exitcode.c
+++ b/arch/um/kernel/exitcode.c
@@ -40,9 +40,11 @@ static ssize_t exitcode_proc_write(struct file *file,
const char __user *buffer, size_t count, loff_t *pos)
{
char *end, buf[sizeof("nnnnn\0")];
+ size_t size;
int tmp;
- if (copy_from_user(buf, buffer, count))
+ size = min(count, sizeof(buf));
+ if (copy_from_user(buf, buffer, size))
return -EFAULT;
tmp = simple_strtol(buf, &end, 0);
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 36e12f0cefd5..1d8505b1e290 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -337,6 +337,8 @@ static struct irq_chip normal_irq_type = {
.irq_disable = dummy,
.irq_enable = dummy,
.irq_ack = dummy,
+ .irq_mask = dummy,
+ .irq_unmask = dummy,
};
static struct irq_chip SIGVTALRM_irq_type = {
@@ -344,6 +346,8 @@ static struct irq_chip SIGVTALRM_irq_type = {
.irq_disable = dummy,
.irq_enable = dummy,
.irq_ack = dummy,
+ .irq_mask = dummy,
+ .irq_unmask = dummy,
};
void __init init_IRQ(void)
diff --git a/arch/um/kernel/maccess.c b/arch/um/kernel/maccess.c
new file mode 100644
index 000000000000..1f3d5c4910d1
--- /dev/null
+++ b/arch/um/kernel/maccess.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
+ *
+ * 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/uaccess.h>
+#include <linux/kernel.h>
+#include <os.h>
+
+long probe_kernel_read(void *dst, const void *src, size_t size)
+{
+ void *psrc = (void *)rounddown((unsigned long)src, PAGE_SIZE);
+
+ if ((unsigned long)src < PAGE_SIZE || size <= 0)
+ return -EFAULT;
+
+ if (os_mincore(psrc, size + src - psrc) <= 0)
+ return -EFAULT;
+
+ return __probe_kernel_read(dst, src, size);
+}
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 7ddb64baf327..8636e905426f 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -279,8 +279,12 @@ pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
struct page *pte;
pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
- if (pte)
- pgtable_page_ctor(pte);
+ if (!pte)
+ return NULL;
+ if (!pgtable_page_ctor(pte)) {
+ __free_page(pte);
+ return NULL;
+ }
return pte;
}
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index bbcef522bcb1..eecc4142764c 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -82,19 +82,8 @@ void *__switch_to(struct task_struct *from, struct task_struct *to)
to->thread.prev_sched = from;
set_current(to);
- do {
- current->thread.saved_task = NULL;
-
- switch_threads(&from->thread.switch_buf,
- &to->thread.switch_buf);
-
- arch_switch_to(current);
-
- if (current->thread.saved_task)
- show_regs(&(current->thread.regs));
- to = current->thread.saved_task;
- from = current;
- } while (current->thread.saved_task);
+ switch_threads(&from->thread.switch_buf, &to->thread.switch_buf);
+ arch_switch_to(current);
return current->thread.prev_sched;
}
diff --git a/arch/um/kernel/sysrq.c b/arch/um/kernel/sysrq.c
index 0dc4d1c6f98a..4d6fdf68edf3 100644
--- a/arch/um/kernel/sysrq.c
+++ b/arch/um/kernel/sysrq.c
@@ -1,6 +1,10 @@
/*
* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
+ * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
+ *
+ * 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/kallsyms.h>
@@ -8,59 +12,87 @@
#include <linux/module.h>
#include <linux/sched.h>
#include <asm/sysrq.h>
+#include <os.h>
-/* Catch non-i386 SUBARCH's. */
-#if !defined(CONFIG_UML_X86) || defined(CONFIG_64BIT)
-void show_trace(struct task_struct *task, unsigned long * stack)
+struct stack_frame {
+ struct stack_frame *next_frame;
+ unsigned long return_address;
+};
+
+static void print_stack_trace(unsigned long *sp, unsigned long bp)
{
+ int reliable;
unsigned long addr;
+ struct stack_frame *frame = (struct stack_frame *)bp;
- if (!stack) {
- stack = (unsigned long*) &stack;
- WARN_ON(1);
- }
-
- printk(KERN_INFO "Call Trace: \n");
- while (((long) stack & (THREAD_SIZE-1)) != 0) {
- addr = *stack;
+ printk(KERN_INFO "Call Trace:\n");
+ while (((long) sp & (THREAD_SIZE-1)) != 0) {
+ addr = *sp;
if (__kernel_text_address(addr)) {
- printk(KERN_INFO "%08lx: [<%08lx>]",
- (unsigned long) stack, addr);
- print_symbol(KERN_CONT " %s", addr);
+ reliable = 0;
+ if ((unsigned long) sp == bp + sizeof(long)) {
+ frame = frame ? frame->next_frame : NULL;
+ bp = (unsigned long)frame;
+ reliable = 1;
+ }
+
+ printk(KERN_INFO " [<%08lx>]", addr);
+ printk(KERN_CONT " %s", reliable ? "" : "? ");
+ print_symbol(KERN_CONT "%s", addr);
printk(KERN_CONT "\n");
}
- stack++;
+ sp++;
}
printk(KERN_INFO "\n");
}
-#endif
-/*Stolen from arch/i386/kernel/traps.c */
-static const int kstack_depth_to_print = 24;
+static unsigned long get_frame_pointer(struct task_struct *task,
+ struct pt_regs *segv_regs)
+{
+ if (!task || task == current)
+ return segv_regs ? PT_REGS_BP(segv_regs) : current_bp();
+ else
+ return KSTK_EBP(task);
+}
-/* This recently started being used in arch-independent code too, as in
- * kernel/sched/core.c.*/
-void show_stack(struct task_struct *task, unsigned long *esp)
+static unsigned long *get_stack_pointer(struct task_struct *task,
+ struct pt_regs *segv_regs)
{
- unsigned long *stack;
+ if (!task || task == current)
+ return segv_regs ? (unsigned long *)PT_REGS_SP(segv_regs) : current_sp();
+ else
+ return (unsigned long *)KSTK_ESP(task);
+}
+
+void show_stack(struct task_struct *task, unsigned long *stack)
+{
+ unsigned long *sp = stack, bp = 0;
+ struct pt_regs *segv_regs = current->thread.segv_regs;
int i;
- if (esp == NULL) {
- if (task != current && task != NULL) {
- esp = (unsigned long *) KSTK_ESP(task);
- } else {
- esp = (unsigned long *) &esp;
- }
+ if (!segv_regs && os_is_signal_stack()) {
+ printk(KERN_ERR "Received SIGSEGV in SIGSEGV handler,"
+ " aborting stack trace!\n");
+ return;
}
- stack = esp;
- for (i = 0; i < kstack_depth_to_print; i++) {
+#ifdef CONFIG_FRAME_POINTER
+ bp = get_frame_pointer(task, segv_regs);
+#endif
+
+ if (!stack)
+ sp = get_stack_pointer(task, segv_regs);
+
+ printk(KERN_INFO "Stack:\n");
+ stack = sp;
+ for (i = 0; i < 3 * STACKSLOTS_PER_LINE; i++) {
if (kstack_end(stack))
break;
- if (i && ((i % 8) == 0))
- printk(KERN_INFO " ");
- printk(KERN_CONT "%08lx ", *stack++);
+ if (i && ((i % STACKSLOTS_PER_LINE) == 0))
+ printk(KERN_CONT "\n");
+ printk(KERN_CONT " %08lx", *stack++);
}
+ printk(KERN_CONT "\n");
- show_trace(task, esp);
+ print_stack_trace(sp, bp);
}
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index 089f3987e273..974b87474a99 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -30,8 +30,7 @@ int handle_page_fault(unsigned long address, unsigned long ip,
pmd_t *pmd;
pte_t *pte;
int err = -EFAULT;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
- (is_write ? FAULT_FLAG_WRITE : 0);
+ unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
*code_out = SEGV_MAPERR;
@@ -42,6 +41,8 @@ int handle_page_fault(unsigned long address, unsigned long ip,
if (in_atomic())
goto out_nosemaphore;
+ if (is_user)
+ flags |= FAULT_FLAG_USER;
retry:
down_read(&mm->mmap_sem);
vma = find_vma(mm, address);
@@ -58,12 +59,15 @@ retry:
good_area:
*code_out = SEGV_ACCERR;
- if (is_write && !(vma->vm_flags & VM_WRITE))
- goto out;
-
- /* Don't require VM_READ|VM_EXEC for write faults! */
- if (!is_write && !(vma->vm_flags & (VM_READ | VM_EXEC)))
- goto out;
+ if (is_write) {
+ if (!(vma->vm_flags & VM_WRITE))
+ goto out;
+ flags |= FAULT_FLAG_WRITE;
+ } else {
+ /* Don't require VM_READ|VM_EXEC for write faults! */
+ if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
+ goto out;
+ }
do {
int fault;
@@ -124,6 +128,8 @@ out_of_memory:
* (which will retry the fault, or kill us if we got oom-killed).
*/
up_read(&mm->mmap_sem);
+ if (!is_user)
+ goto out_nosemaphore;
pagefault_out_of_memory();
return 0;
}
@@ -200,9 +206,12 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
int is_write = FAULT_WRITE(fi);
unsigned long address = FAULT_ADDRESS(fi);
+ if (regs)
+ current->thread.segv_regs = container_of(regs, struct pt_regs, regs);
+
if (!is_user && (address >= start_vm) && (address < end_vm)) {
flush_tlb_kernel_vm();
- return 0;
+ goto out;
}
else if (current->mm == NULL) {
show_regs(container_of(regs, struct pt_regs, regs));
@@ -224,7 +233,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
catcher = current->thread.fault_catcher;
if (!err)
- return 0;
+ goto out;
else if (catcher != NULL) {
current->thread.fault_addr = (void *) address;
UML_LONGJMP(catcher, 1);
@@ -232,7 +241,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
else if (current->thread.fault_addr != NULL)
panic("fault_addr set but no fault catcher");
else if (!is_user && arch_fixup(ip, regs))
- return 0;
+ goto out;
if (!is_user) {
show_regs(container_of(regs, struct pt_regs, regs));
@@ -256,6 +265,11 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
current->thread.arch.faultinfo = fi;
force_sig_info(SIGSEGV, &si, current);
}
+
+out:
+ if (regs)
+ current->thread.segv_regs = NULL;
+
return 0;
}
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 87df5e3acc26..016adf0985d5 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -13,6 +13,7 @@
#include <linux/sched.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
+#include <asm/sections.h>
#include <asm/setup.h>
#include <as-layout.h>
#include <arch.h>
@@ -234,7 +235,6 @@ static int panic_exit(struct notifier_block *self, unsigned long unused1,
void *unused2)
{
bust_spinlocks(1);
- show_regs(&(current->thread.regs));
bust_spinlocks(0);
uml_exitcode = 1;
os_dump_core();