From: Ingo Molnar <[email protected]>
improved the print-fatal-signals debug output:
hotplug/825: potentially unexpected fatal signal 11.
code at ffffe400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
vDSO at b7f41000
Pid: 825, comm: hotplug
EIP: 0073:[<ffffe400>] CPU: 0
EIP is at 0xffffe400
ESP: 007b:bff52910 EFLAGS: 00010246 Not tainted (2.6.17-rc4 #91)
EAX: 000000af EBX: 00000000 ECX: 00000000 EDX: 080f341c
ESI: 00000008 EDI: 41c9eff4 EBP: bff529ac DS: 007b ES: 007b
CR0: 8005003b CR2: ffffe40f CR3: 372a3000 CR4: 00000680
[<c0103fad>] show_trace+0xd/0x10
[<c0101637>] show_regs+0x177/0x180
[<c0123d13>] get_signal_to_deliver+0x3f3/0x7d0
[<c010278c>] do_notify_resume+0x1bc/0x750
[<c0102ebe>] work_notifysig+0x13/0x19
08047000-080e9000 r-xp 00000000 03:01 3547392 /bin/bash
080e9000-080ef000 rw-p 000a1000 03:01 3547392 /bin/bash
080ef000-080f4000 rw-p 080ef000 00:00 0 [heap]
41b5a000-41b73000 r-xp 00000000 03:01 846154 /lib/ld-2.3.90.so
41b73000-41b74000 r--p 00018000 03:01 846154 /lib/ld-2.3.90.so
41b74000-41b75000 rw-p 00019000 03:01 846154 /lib/ld-2.3.90.so
41b77000-41c9d000 r-xp 00000000 03:01 846155 /lib/libc-2.3.90.so
41c9d000-41c9f000 r--p 00125000 03:01 846155 /lib/libc-2.3.90.so
41c9f000-41ca1000 rw-p 00127000 03:01 846155 /lib/libc-2.3.90.so
41ca1000-41ca3000 rw-p 41ca1000 00:00 0
41ccc000-41cce000 r-xp 00000000 03:01 846157 /lib/libdl-2.3.90.so
41cce000-41ccf000 r--p 00001000 03:01 846157 /lib/libdl-2.3.90.so
41ccf000-41cd0000 rw-p 00002000 03:01 846157 /lib/libdl-2.3.90.so
41dce000-41dd1000 r-xp 00000000 03:01 846175 /lib/libtermcap.so.2.0.8
41dd1000-41dd2000 rw-p 00002000 03:01 846175 /lib/libtermcap.so.2.0.8
b7f29000-b7f2a000 rw-p b7f29000 00:00 0
b7f40000-b7f41000 rw-p b7f40000 00:00 0
b7f41000-b7f42000 r-xp b7f41000 00:00 0 [vdso]
bff3e000-bff53000 rw-p bff3e000 00:00 0 [stack]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Arjan van de Ven <[email protected]>
---
kernel/signal.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 95 insertions(+), 2 deletions(-)
Index: linux-vdso-rand.q/kernel/signal.c
===================================================================
--- linux-vdso-rand.q.orig/kernel/signal.c
+++ linux-vdso-rand.q/kernel/signal.c
@@ -16,6 +16,7 @@
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/sched.h>
+#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
@@ -763,7 +764,95 @@ out_set:
#define LEGACY_QUEUE(sigptr, sig) \
(((sig) < SIGRTMIN) && sigismember(&(sigptr)->signal, (sig)))
-int print_fatal_signals = 0;
+int print_fatal_signals;
+
+static void pad_len_spaces(int len)
+{
+ len = 25 + sizeof(void*) * 6 - len;
+
+ if (len < 1)
+ len = 1;
+
+ printk("%*c", len, ' ');
+}
+
+static int print_vma(struct vm_area_struct *vma)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ struct file *file = vma->vm_file;
+ int flags = vma->vm_flags;
+ unsigned long ino = 0;
+ dev_t dev = 0;
+ int len;
+
+ if (file) {
+ struct inode *inode = vma->vm_file->f_dentry->d_inode;
+ dev = inode->i_sb->s_dev;
+ ino = inode->i_ino;
+ }
+
+ printk("%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
+ vma->vm_start,
+ vma->vm_end,
+ flags & VM_READ ? 'r' : '-',
+ flags & VM_WRITE ? 'w' : '-',
+ flags & VM_EXEC ? 'x' : '-',
+ flags & VM_MAYSHARE ? 's' : 'p',
+ vma->vm_pgoff << PAGE_SHIFT,
+ MAJOR(dev), MINOR(dev), ino, &len);
+
+ /*
+ * Print the dentry name for named mappings, and a
+ * special [heap] marker for the heap:
+ */
+ if (file) {
+#define SIZE 128
+ char tmp[SIZE], *str;
+
+ str = d_path(file->f_dentry, file->f_vfsmnt, tmp, SIZE);
+ while (str[0] && (str[0] == ' '))
+ str++;
+
+ pad_len_spaces(len);
+ printk("%s", str);
+ } else {
+ const char *name = arch_vma_name(vma);
+ if (!name) {
+ if (mm) {
+ if (vma->vm_start <= mm->start_brk &&
+ vma->vm_end >= mm->brk) {
+ name = "[heap]";
+ } else if (vma->vm_start <= mm->start_stack &&
+ vma->vm_end >= mm->start_stack) {
+ name = "[stack]";
+ }
+ } else {
+ name = "[vdso]";
+ }
+ }
+ if (name) {
+ pad_len_spaces(len);
+ printk(name);
+ }
+ }
+ printk("\n");
+
+ return 0;
+}
+
+static void print_vmas(void)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = current->mm;
+
+ if (!mm)
+ return;
+
+ down_read(&mm->mmap_sem);
+ for (vma = mm->mmap; vma; vma = vma->vm_next)
+ print_vma(vma);
+ up_read(&mm->mmap_sem);
+}
static void print_fatal_signal(struct pt_regs *regs, int signr)
{
@@ -781,9 +870,13 @@ static void print_fatal_signal(struct pt
printk("%02x ", insn);
}
}
-#endif
printk("\n");
+ if (current->mm)
+ printk("vDSO at %p\n", current->mm->context.vdso);
+#endif
show_regs(regs);
+ printk("\n");
+ print_vmas();
}
static int __init setup_print_fatal_signals(char *str)
Ingo Molnar wrote:
>
> static void print_fatal_signal(struct pt_regs *regs, int signr)
> {
> @@ -781,9 +870,13 @@ static void print_fatal_signal(struct pt
> printk("%02x ", insn);
> }
> }
> -#endif
> printk("\n");
> + if (current->mm)
> + printk("vDSO at %p\n", current->mm->context.vdso);
> +#endif
> show_regs(regs);
> + printk("\n");
> + print_vmas();
> }
>
> static int __init setup_print_fatal_signals(char *str
Perhaps I should have read your first patch more carefully - it did have
register info. This looks even better (although you may now want to
allow it to be #ifdef'd out under CONFIG_EMBEDDED).
You probably should use PATH_MAX+1 instead of SIZE or check IS_ERR() on
the string from d_path.
Zach
* Zachary Amsden <[email protected]> wrote:
> >+ if (current->mm)
> >+ printk("vDSO at %p\n", current->mm->context.vdso);
> >+#endif
> > show_regs(regs);
> >+ printk("\n");
> >+ print_vmas();
> > }
> >
> > static int __init setup_print_fatal_signals(char *str
>
> Perhaps I should have read your first patch more carefully - it did
> have register info. This looks even better (although you may now want
> to allow it to be #ifdef'd out under CONFIG_EMBEDDED).
>
> You probably should use PATH_MAX+1 instead of SIZE or check IS_ERR()
> on the string from d_path.
the string is constructed on the stack, so 4K would be too much. 128 is
i think enough for most purposes.
Ingo