The quilt patch titled
Subject: kfence: replace local_clock() with ktime_get_boot_fast_ns()
has been removed from the -mm tree. Its filename was
kfence-replace-local_clock-with-ktime_get_boot_fast_ns.patch
This patch was dropped because it was nacked
------------------------------------------------------
From: Juntong Deng <juntong.deng@xxxxxxxxxxx>
Subject: kfence: replace local_clock() with ktime_get_boot_fast_ns()
Date: Wed, 22 Nov 2023 20:00:26 +0000
The time obtained by local_clock() is the local CPU time, which may
drift between CPUs and is not suitable for comparison across CPUs.
It is possible for allocation and free to occur on different CPUs,
and using local_clock() to record timestamps may cause confusion.
ktime_get_boot_fast_ns() is based on clock sources and can be used
reliably and accurately for comparison across CPUs.
Link: https://lkml.kernel.org/r/VI1P193MB0752A2F21C050D701945B62799BAA@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Juntong Deng <juntong.deng@xxxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/kfence/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/kfence/core.c~kfence-replace-local_clock-with-ktime_get_boot_fast_ns
+++ a/mm/kfence/core.c
@@ -295,7 +295,7 @@ metadata_update_state(struct kfence_meta
track->num_stack_entries = num_stack_entries;
track->pid = task_pid_nr(current);
track->cpu = raw_smp_processor_id();
- track->ts_nsec = local_clock(); /* Same source as printk timestamps. */
+ track->ts_nsec = ktime_get_boot_fast_ns();
/*
* Pairs with READ_ONCE() in
_
Patches currently in -mm which might be from juntong.deng@xxxxxxxxxxx are
kasan-improve-free-meta-storage-in-generic-kasan.patch
