From: Rohit Thapliyal <[email protected]>
On 64bit kernel, the dump_mem gives 32 bit addresses
on the stack dump. This gives unorganized information regarding
the 64bit values on the stack. Hence, modified to get a complete 64bit memory
dump.
With patch:
[ 93.534801] Process insmod (pid: 1587, stack limit = 0xffffffc976be4058)
[ 93.541441] Stack: (0xffffffc976be7cf0 to 0xffffffc976be8000)
[ 93.547136] 7ce0: ffffffc976be7d00 ffffffc00008163c
[ 93.554898] 7d00: ffffffc976be7d40 ffffffc0000f8a44 ffffffc00098ef38 ffffffbffc000088
[ 93.562659] 7d20: ffffffc00098ef50 ffffffbffc0000c0 0000000000000001 ffffffbffc000070
[ 93.570419] 7d40: ffffffc976be7e40 ffffffc0000f935c 0000000000000000 000000002b424090
[ 93.578179] 7d60: 000000002b424010 0000007facc555f4 0000000080000000 0000000000000015
[ 93.585937] 7d80: 0000000000000116 0000000000000069 ffffffc00097b000 ffffffc976be4000
[ 93.593694] 7da0: 0000000000000064 0000000000000072 000000000000006e 000000000000003f
[ 93.601453] 7dc0: 000000000000feff 000000000000fff1 ffffffbffc002028 0000000000000124
[ 93.609211] 7de0: ffffffc976be7e10 0000000000000001 ffffff8000000000 ffffffbbffff0000
[ 93.616969] 7e00: ffffffc976be7e60 0000000000000000 0000000000000000 0000000000000000
[ 93.624726] 7e20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[ 93.632484] 7e40: 0000007fcc474550 ffffffc0000841ec 000000002b424010 0000007facda0710
[ 93.640241] 7e60: ffffffffffffffff ffffffc0000be6dc ffffff80007d2000 000000000001c010
[ 93.647999] 7e80: ffffff80007e0ae0 ffffff80007e09d0 ffffff80007edf70 0000000000000288
[ 93.655757] 7ea0: 00000000000002e8 0000000000000000 0000000000000000 0000001c0000001b
[ 93.663514] 7ec0: 0000000000000009 0000000000000007 000000002b424090 000000000001c010
[ 93.671272] 7ee0: 000000002b424010 0000007faccd3a48 0000000000000000 0000000000000000
[ 93.679030] 7f00: 0000007fcc4743f8 0000007fcc4743f8 0000000000000069 0000000000000003
[ 93.686787] 7f20: 0101010101010101 0000000000000004 0000000000000020 00000000000003f3
[ 93.694544] 7f40: 0000007facb95664 0000007facda7030 0000007facc555d0 0000000000498378
[ 93.702301] 7f60: 0000000000000000 000000002b424010 0000007facda0710 000000002b424090
[ 93.710058] 7f80: 0000007fcc474698 0000000000498000 0000007fcc474ebb 0000000000474f58
[ 93.717815] 7fa0: 0000000000498000 0000000000000000 0000000000000000 0000007fcc474550
[ 93.725573] 7fc0: 00000000004104bc 0000007fcc474430 0000007facc555f4 0000000080000000
[ 93.733330] 7fe0: 000000002b424090 0000000000000069 0950020128000244 4104000008000004
[ 93.741084] Call trace:
The above output makes a debugger life a lot more easier.
Signed-off-by: Rohit Thapliyal <[email protected]>
Signed-off-by: Maninder Singh <[email protected]>
---
v1: added new function dump_mem64
v2: remove seprate function, modified dump_mem
v3: Changelog modified
v4: Used compat_user_mode() for setting width to 4 or 8
arch/arm64/kernel/traps.c | 31 +++++++++++++++++++++----------
1 file changed, 21 insertions(+), 10 deletions(-)
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 1ef2940..97e6208 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -52,11 +52,12 @@ int show_unhandled_signals = 1;
* Dump out the contents of some memory nicely...
*/
static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
- unsigned long top)
+ unsigned long top, bool wide)
{
unsigned long first;
mm_segment_t fs;
int i;
+ unsigned int width = wide ? 4 : 8;
/*
* We need to switch to kernel mode so that we can use __get_user
@@ -75,13 +76,22 @@ static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
memset(str, ' ', sizeof(str));
str[sizeof(str) - 1] = '\0';
- for (p = first, i = 0; i < 8 && p < top; i++, p += 4) {
+ for (p = first, i = 0; i < (32 / width)
+ && p < top; i++, p += width) {
if (p >= bottom && p < top) {
- unsigned int val;
- if (__get_user(val, (unsigned int *)p) == 0)
- sprintf(str + i * 9, " %08x", val);
- else
- sprintf(str + i * 9, " ????????");
+ unsigned long val;
+
+ if (width == 8) {
+ if (__get_user(val, (unsigned long *)p) == 0)
+ sprintf(str + i * 17, " %016lx", val);
+ else
+ sprintf(str + i * 17, " ????????????????");
+ } else {
+ if (__get_user(val, (unsigned int *)p) == 0)
+ sprintf(str + i * 9, " %08lx", val);
+ else
+ sprintf(str + i * 9, " ????????");
+ }
}
}
printk("%s%04lx:%s\n", lvl, first & 0xffff, str);
@@ -95,7 +105,7 @@ static void dump_backtrace_entry(unsigned long where, unsigned long stack)
print_ip_sym(where);
if (in_exception_text(where))
dump_mem("", "Exception stack", stack,
- stack + sizeof(struct pt_regs));
+ stack + sizeof(struct pt_regs), false);
}
static void dump_instr(const char *lvl, struct pt_regs *regs)
@@ -206,8 +216,9 @@ static int __die(const char *str, int err, struct thread_info *thread,
TASK_COMM_LEN, tsk->comm, task_pid_nr(tsk), thread + 1);
if (!user_mode(regs) || in_interrupt()) {
- dump_mem(KERN_EMERG, "Stack: ", regs->sp,
- THREAD_SIZE + (unsigned long)task_stack_page(tsk));
+ dump_mem(KERN_EMERG, "Stack: ", regs->sp,
+ THREAD_SIZE + (unsigned long)task_stack_page(tsk),
+ compat_user_mode(regs));
dump_backtrace(regs, tsk);
dump_instr(KERN_EMERG, regs);
}
--
1.7.9.5
On Thu, Jul 09, 2015 at 11:30:34AM +0530, Maninder Singh wrote:
> diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
> index 1ef2940..97e6208 100644
> --- a/arch/arm64/kernel/traps.c
> +++ b/arch/arm64/kernel/traps.c
> @@ -52,11 +52,12 @@ int show_unhandled_signals = 1;
> * Dump out the contents of some memory nicely...
> */
> static void dump_mem(const char *lvl, const char *str, unsigned long bottom,
> - unsigned long top)
> + unsigned long top, bool wide)
> {
> unsigned long first;
> mm_segment_t fs;
> int i;
> + unsigned int width = wide ? 4 : 8;
I was thinking the other way around, i.e. wide means 64-bit, narrow
32-bit.
Anyway, just rename "wide" to "compat" here, it makes even more sense.
The rest of the patch looks fine:
Reviewed-by: Catalin Marinas <[email protected]>
Will can pick it up for 4.3.
Thanks.
--
Catalin