The patch titled
Subject: kmemleak: add option to print warnings to dmesg
has been removed from the -mm tree. Its filename was
kmemleak-add-option-to-print-warnings-to-dmesg.patch
This patch was dropped because an updated version will be merged
------------------------------------------------------
From: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx>
Subject: kmemleak: add option to print warnings to dmesg
Currently, kmemleak only prints the number of suspected leaks to dmesg but
requires the user to read a debugfs file to get the actual stack traces of
the objects' allocation points. Add an option to print the full object
information to dmesg too. This allows easier integration of kmemleak into
automated test systems since those kind of systems presumably already save
kernel logs.
Link: http://lkml.kernel.org/r/20180827083821.7706-1-vincent.whitchurch@xxxxxxxx
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/Kconfig.debug | 9 +++++++++
mm/kmemleak.c | 37 ++++++++++++++++++++++++++++++-------
2 files changed, 39 insertions(+), 7 deletions(-)
--- a/lib/Kconfig.debug~kmemleak-add-option-to-print-warnings-to-dmesg
+++ a/lib/Kconfig.debug
@@ -593,6 +593,15 @@ config DEBUG_KMEMLEAK_DEFAULT_OFF
Say Y here to disable kmemleak by default. It can then be enabled
on the command line via kmemleak=on.
+config DEBUG_KMEMLEAK_WARN
+ bool "Print kmemleak object warnings to log buffer"
+ depends on DEBUG_KMEMLEAK
+ help
+ Say Y here to make kmemleak print information about unreferenced
+ objects (including stacktraces) as warnings to the kernel log buffer.
+ Otherwise this information is only available by reading the kmemleak
+ debugfs file.
+
config DEBUG_STACK_USAGE
bool "Stack utilization instrumentation"
depends on DEBUG_KERNEL && !IA64
--- a/mm/kmemleak.c~kmemleak-add-option-to-print-warnings-to-dmesg
+++ a/mm/kmemleak.c
@@ -181,6 +181,7 @@ struct kmemleak_object {
/* flag set to not scan the object */
#define OBJECT_NO_SCAN (1 << 2)
+#define HEX_PREFIX " "
/* number of bytes to print per line; must be 16 or 32 */
#define HEX_ROW_SIZE 16
/* number of bytes to print at a time (1, 2, 4, 8) */
@@ -299,6 +300,25 @@ static void kmemleak_disable(void);
kmemleak_disable(); \
} while (0)
+#define warn_or_seq_printf(seq, fmt, ...) do { \
+ if (seq) \
+ seq_printf(seq, fmt, ##__VA_ARGS__); \
+ else \
+ pr_warn(fmt, ##__VA_ARGS__); \
+} while (0)
+
+static void warn_or_seq_hex_dump(struct seq_file *seq, int prefix_type,
+ int rowsize, int groupsize, const void *buf,
+ size_t len, bool ascii)
+{
+ if (seq)
+ seq_hex_dump(seq, HEX_PREFIX, prefix_type, rowsize, groupsize,
+ buf, len, ascii);
+ else
+ print_hex_dump(KERN_WARNING, pr_fmt(HEX_PREFIX), prefix_type,
+ rowsize, groupsize, buf, len, ascii);
+}
+
/*
* Printing of the objects hex dump to the seq file. The number of lines to be
* printed is limited to HEX_MAX_LINES to prevent seq file spamming. The
@@ -314,10 +334,10 @@ static void hex_dump_object(struct seq_f
/* limit the number of lines to HEX_MAX_LINES */
len = min_t(size_t, object->size, HEX_MAX_LINES * HEX_ROW_SIZE);
- seq_printf(seq, " hex dump (first %zu bytes):\n", len);
+ warn_or_seq_printf(seq, " hex dump (first %zu bytes):\n", len);
kasan_disable_current();
- seq_hex_dump(seq, " ", DUMP_PREFIX_NONE, HEX_ROW_SIZE,
- HEX_GROUP_SIZE, ptr, len, HEX_ASCII);
+ warn_or_seq_hex_dump(seq, DUMP_PREFIX_NONE, HEX_ROW_SIZE,
+ HEX_GROUP_SIZE, ptr, len, HEX_ASCII);
kasan_enable_current();
}
@@ -365,17 +385,17 @@ static void print_unreferenced(struct se
int i;
unsigned int msecs_age = jiffies_to_msecs(jiffies - object->jiffies);
- seq_printf(seq, "unreferenced object 0x%08lx (size %zu):\n",
+ warn_or_seq_printf(seq, "unreferenced object 0x%08lx (size %zu):\n",
object->pointer, object->size);
- seq_printf(seq, " comm \"%s\", pid %d, jiffies %lu (age %d.%03ds)\n",
+ warn_or_seq_printf(seq, " comm \"%s\", pid %d, jiffies %lu (age %d.%03ds)\n",
object->comm, object->pid, object->jiffies,
msecs_age / 1000, msecs_age % 1000);
hex_dump_object(seq, object);
- seq_printf(seq, " backtrace:\n");
+ warn_or_seq_printf(seq, " backtrace:\n");
for (i = 0; i < object->trace_len; i++) {
void *ptr = (void *)object->trace[i];
- seq_printf(seq, " [<%p>] %pS\n", ptr, ptr);
+ warn_or_seq_printf(seq, " [<%p>] %pS\n", ptr, ptr);
}
}
@@ -1598,6 +1618,9 @@ static void kmemleak_scan(void)
if (unreferenced_object(object) &&
!(object->flags & OBJECT_REPORTED)) {
object->flags |= OBJECT_REPORTED;
+#ifdef CONFIG_DEBUG_KMEMLEAK_WARN
+ print_unreferenced(NULL, object);
+#endif
new_leaks++;
}
spin_unlock_irqrestore(&object->lock, flags);
_
Patches currently in -mm which might be from vincent.whitchurch@xxxxxxxx are
kmemleak-always-register-debugfs-file.patch
kmemleak-add-module-param-to-print-warnings-to-dmesg.patch
