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[104.155.91.135]) by smtp.gmail.com with ESMTPSA id 4fb4d7f45d1cf-6a69a010c72sm997336a12.8.2026.09.03.08.19.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 03 Sep 2026 08:19:59 -0700 (PDT) Date: Thu, 3 Sep 2026 16:19:55 +0100 From: Vincent Donnefort To: Steven Rostedt Cc: mhiramat@kernel.org, linux-trace-kernel@vger.kernel.org, mathieu.desnoyers@efficios.com, kernel-team@android.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v9 0/4] ring-buffer: Fixes for subbuf resizing and persistent buffers Message-ID: References: <20260901155445.1475405-1-vdonnefort@google.com> <20260903103116.6cb7c39c@gandalf.local.home> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260903103116.6cb7c39c@gandalf.local.home> On Thu, Sep 03, 2026 at 10:31:16AM -0400, Steven Rostedt wrote: > On Tue, 1 Sep 2026 16:54:41 +0100 > Vincent Donnefort wrote: > > > This series addresses multiple issues discovered with the dynamic ring > > buffer resizing. > > > > I have managed to reproduce a ring_buffer_read_page() race with > > > > $ while true; do for i in 8 16 32; do echo $i > /sys/kernel/tracing/buffer_subbuf_size_kb; sleep 0.1; done; done > > Did you do anything else while running the above? > > I ask because I ran this for several hours and it didn't produce anything. > What bug does it supposed to trigger? > > -- Steve I clearly have been imprecise here. I had "trace-record -e sched" and I have just verified with a print that it has run into the reader->order != read_page->order case. -- Vincent