From: Tao Cui <cui.tao@linux.dev>
To: tj@kernel.org, axboe@kernel.dk
Cc: josef@toxicpanda.com, cgroups@vger.kernel.org,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
cui.tao@linux.dev, Tao Cui <cuitao@kylinos.cn>
Subject: [PATCH] block/blk-iocost: read ioc_pd_stat params inside ioc->lock
Date: Sun, 2 Aug 2026 23:09:13 +0800 [thread overview]
Message-ID: <20260802150913.31977-1-cui.tao@linux.dev> (raw)
From: Tao Cui <cuitao@kylinos.cn>
ioc_pd_stat() reads ioc->enabled, ioc->vtime_base_rate, and
iocg->last_stat without holding ioc->lock, which trips KCSAN since
ioc_adjust_base_vrate() and iocg_flush_stat_upward() write those
fields under ioc->lock.
Commit 35198e323001 ("blk-iocost: read params inside lock in sysfs
apis") fixed the same issue in ioc_qos_prfill() and
ioc_cost_model_prfill(), but ioc_pd_stat() was missed.
Add spin_lock_irq(&ioc->lock) around the reads, matching the fix
style of 35198e323001.
Fixes: 35198e323001 ("blk-iocost: read params inside lock in sysfs apis")
Signed-off-by: Tao Cui <cuitao@kylinos.cn>
---
block/blk-iocost.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 8b2aeba2e1e3..b491a6ab98ea 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -3093,8 +3093,10 @@ static void ioc_pd_stat(struct blkg_policy_data *pd, struct seq_file *s)
struct ioc_gq *iocg = pd_to_iocg(pd);
struct ioc *ioc = iocg->ioc;
+ spin_lock_irq(&ioc->lock);
+
if (!ioc->enabled)
- return;
+ goto out;
if (iocg->level == 0) {
unsigned vp10k = DIV64_U64_ROUND_CLOSEST(
@@ -3110,6 +3112,8 @@ static void ioc_pd_stat(struct blkg_policy_data *pd, struct seq_file *s)
iocg->last_stat.wait_us,
iocg->last_stat.indebt_us,
iocg->last_stat.indelay_us);
+out:
+ spin_unlock_irq(&ioc->lock);
}
static u64 ioc_weight_prfill(struct seq_file *sf, struct blkg_policy_data *pd,
--
2.43.0
reply other threads:[~2026-08-02 15:09 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260802150913.31977-1-cui.tao@linux.dev \
--to=cui.tao@linux.dev \
--cc=axboe@kernel.dk \
--cc=cgroups@vger.kernel.org \
--cc=cuitao@kylinos.cn \
--cc=josef@toxicpanda.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox