diff options
| author | Juntong Deng <juntong.deng@outlook.com> | 2024-02-15 18:39:55 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-02-22 15:27:20 -0800 |
| commit | 952237b5a9b79acf1212b40ad1e993557e3cb0ca (patch) | |
| tree | d580e12f93960eea9d2e17d8257207bce102ffbb | |
| parent | 059ab7be09d4ff0cab4f43ffbf225a2693da0bd7 (diff) | |
kasan: increase the number of bits to shift when recording extra timestamps
In 5d4c6ac94694 ("kasan: record and report more information") I thought
that printk only displays a maximum of 99999 seconds, but actually printk
can display a larger number of seconds.
So increase the number of bits to shift when recording the extra timestamp
(44 bits), without affecting the precision, shift it right by 9 bits,
discarding all bits that do not affect the microsecond part (nanoseconds
will not be shown).
Currently the maximum time that can be displayed is 9007199.254740s,
because
11111111111111111111111111111111111111111111 (44 bits) << 9
= 11111111111111111111111111111111111111111111000000000
= 9007199.254740
Link: https://lkml.kernel.org/r/AM6PR03MB58481629F2F28CE007412139994D2@AM6PR03MB5848.eurprd03.prod.outlook.com
Fixes: 5d4c6ac94694 ("kasan: record and report more information")
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Acked-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/kasan/common.c | 2 | ||||
| -rw-r--r-- | mm/kasan/report.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 610efae91220..f2747ed30da0 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -55,7 +55,7 @@ void kasan_set_track(struct kasan_track *track, depot_stack_handle_t stack) u64 ts_nsec = local_clock(); track->cpu = cpu; - track->timestamp = ts_nsec >> 3; + track->timestamp = ts_nsec >> 9; #endif /* CONFIG_KASAN_EXTRA_INFO */ track->pid = current->pid; track->stack = stack; diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 7afa4feb03e1..b48c768acc84 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -267,7 +267,7 @@ static void print_track(struct kasan_track *track, const char *prefix) u64 ts_nsec = track->timestamp; unsigned long rem_usec; - ts_nsec <<= 3; + ts_nsec <<= 9; rem_usec = do_div(ts_nsec, NSEC_PER_SEC) / 1000; pr_err("%s by task %u on cpu %d at %lu.%06lus:\n", |