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charset="UTF-8" X-Stat-Signature: sq1yeecppqr5xd7bzf58upeaxjctahty X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 2F24AC00A6 X-Rspam-User: Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=eVrGmjEL; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf10.hostedemail.com: domain of elver@google.com designates 209.85.219.181 as permitted sender) smtp.mailfrom=elver@google.com X-HE-Tag: 1652858705-579301 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 18 May 2022 at 03:03, Jackie Liu wrote: > > From: Jackie Liu > > By printing information, we can friendly prompt the status change > information of kfence by dmesg and record by syslog. > > Co-developed-by: Marco Elver > Signed-off-by: Jackie Liu > --- > v1->v2: > fixup by Marco Elver > v2->v3: > write kfence_enabled=false only true before > > mm/kfence/core.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/mm/kfence/core.c b/mm/kfence/core.c > index 11a954763be9..41840b8d9cb3 100644 > --- a/mm/kfence/core.c > +++ b/mm/kfence/core.c > @@ -67,8 +67,13 @@ static int param_set_sample_interval(const char *val, const struct kernel_param > if (ret < 0) > return ret; > > - if (!num) /* Using 0 to indicate KFENCE is disabled. */ > - WRITE_ONCE(kfence_enabled, false); > + /* Using 0 to indicate KFENCE is disabled. */ > + if (!num) { > + if (READ_ONCE(kfence_enabled)) { Now you could just write if (!num && READ_ONCE(kfence_enabled)) { .... > + pr_info("disabled\n"); > + WRITE_ONCE(kfence_enabled, false); > + } > + } > > *((unsigned long *)kp->arg) = num; > > @@ -874,6 +879,7 @@ static int kfence_enable_late(void) > > WRITE_ONCE(kfence_enabled, true); > queue_delayed_work(system_unbound_wq, &kfence_timer, 0); > + pr_info("re-enabled\n"); > return 0; > } > > -- > 2.25.1 >