The patch titled
Subject: kasan: increase the number of bits to shift when recording extra timestamps
has been added to the -mm mm-unstable branch. Its filename is
kasan-increase-the-number-of-bits-to-shift-when-recording-extra-timestamps.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kasan-increase-the-number-of-bits-to-shift-when-recording-extra-timestamps.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Juntong Deng <juntong.deng@xxxxxxxxxxx>
Subject: kasan: increase the number of bits to shift when recording extra timestamps
Date: Thu, 15 Feb 2024 18:39:55 +0000
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@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 5d4c6ac94694 ("kasan: record and report more information")
Signed-off-by: Juntong Deng <juntong.deng@xxxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/kasan/common.c | 2 +-
mm/kasan/report.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
--- a/mm/kasan/common.c~kasan-increase-the-number-of-bits-to-shift-when-recording-extra-timestamps
+++ a/mm/kasan/common.c
@@ -55,7 +55,7 @@ void kasan_set_track(struct kasan_track
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;
--- a/mm/kasan/report.c~kasan-increase-the-number-of-bits-to-shift-when-recording-extra-timestamps
+++ a/mm/kasan/report.c
@@ -267,7 +267,7 @@ static void print_track(struct kasan_tra
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",
_
Patches currently in -mm which might be from juntong.deng@xxxxxxxxxxx are
kasan-increase-the-number-of-bits-to-shift-when-recording-extra-timestamps.patch
