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Wed, 28 Jan 2026 00:45:48 -0800 (PST) From: Qing Wang To: chen.dylane@gmail.com Cc: acme@kernel.org, adrian.hunter@intel.com, alexander.shishkin@linux.intel.com, andrii.nakryiko@gmail.com, bpf@vger.kernel.org, irogers@google.com, jolsa@kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mark.rutland@arm.com, mingo@redhat.com, namhyung@kernel.org, peterz@infradead.org, radoslaw.zielonek@gmail.com, syzbot+72a43cdb78469f7fbad1@syzkaller.appspotmail.com, wangqing7171@gmail.com Subject: Re: [PATCH] perf callchain: Fix suspicious RCU usage in get_callchain_entry() Date: Wed, 28 Jan 2026 16:45:38 +0800 Message-Id: <20260128084538.1889001-1-wangqing7171@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <874829ba-00b9-49cd-8f67-a4c33a8f409f@gmail.com> References: <874829ba-00b9-49cd-8f67-a4c33a8f409f@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On Wed, 28 Jan 2026 at 16:19, Tao Chen wrote: > I have a change that will remove RCU. As Andrii pointed out, using > get_callchain_entry without RCU lock in BPF appears to be safe for now. > Please point out if I've missed anything. Oh, that's a great way. Thank you for reminding me. -- Best regards, Qing